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L Thomas

Publications and source records attributed to L Thomas.

At least 145 records · Page 8Linked to original sources

Guidelines in professions allied to medicine.

BACKGROUND: Clinical practice guidelines aim to reduce inappropriate variations in practice and to promote the delivery of evidence-based health care. OBJECTIVES: To identify and assess the effects of studies of the introduction of clinical practice guidelines in nursing (including health visiting), midwifery and other professions allied to medicine. SEARCH STRATEGY: We searched the Cochrane Effective Practice and Organisation of Care Group specialised register, MEDLINE (1975 to 1996), EMBASE, Cinahl and Sigle to 1996, the NHS Economic Evaluations Database (1994 to 1996), DHSS-Data (1983 to 1996), the Database of Abstracts of Reviews of Effectiveness (1994 to 1996) and reference lists of articles. We also hand searched the journal Quality in Health Care, made personal contact with content experts and contacted libraries identified by an expert panel. SELECTION CRITERIA: Randomised trials, controlled before-and-after studies and interrupted time series analyses of the introduction of interventions comparing 1. Clinical guidelines plus dissemination and/or implementation strategies versus no guidelines; 2. Guidelines plus dissemination and/or implementation strategies versus guidelines plus alternative dissemination and/or implementation strategies; and 3. (post hoc) Guidelines used by professions allied to medicine versus standard physician care. The participants were nurses, midwives and other professions allied to medicine. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data and assessed study quality. MAIN RESULTS: Eighteen studies were included involving more than 467 health care professionals. The reporting of study methods was inadequate for all studies. In all but one study, nurses were the targeted professional group; one study was aimed solely at dieticians. The various behaviours targeted included the management of hypertension, low back pain and hyperlipidaemia. Nine studies were identified for comparison 1. Three out of five studies observed improvements in at least some processes of care and six out of eight studies observed improvements in outcomes of care. Only one study included a formal economic evaluation, with equivocal findings. Three studies were identified for comparison 2 but it was difficult to draw firm conclusions because of poor methods. Six studies were identified for comparison 3 (post hoc). These studies generally supported the hypothesis that there was no difference between care given by nurses using clinical guidelines and standard physician care. REVIEWER'S CONCLUSIONS: There is some evidence that guideline-driven care is effective in changing the process and outcome of care provided by professions allied to medicine. However, caution is needed in generalising findings to other professions and settings.

Allied Health Personnel↗

Relationship between the length of the perineum and position of the anus and vaginal delivery in primigravidae.

The aim of the study was to determine perineal length and anal position in primigravidae and to evaluate their effect on vaginal delivery. The distances between the fourchette and each of the center of the anal orifice and the inferior margin of the coccyx were measured in 212 primigravidae with singleton term pregnancies during the first stage of labor. Anal position index was calculated by dividing the first measurement by the second. The mean +/- SD length of perineum was 4.6 +/- 0.9 cm. The mean +/- SD anal position index was 0.49 +/- 0.12. Women with a short perineum (<4 cm) or a small anal position index (<0.42) had significantly higher rates of episiotomy, perineal tears and instrumented delivery. This association was also significant by multiple logistic regression analysis. It was concluded that a short perineum and anterior displacement of the anus were associated with traumatic vaginal delivery in primigravidae.

Adult↗

Screening and confirmatory testing for extended spectrum beta-lactamases (ESBL) in Escherichia coli, Klebsiella pneumoniae, and Klebsiella oxytoca clinical isolates.

Escherichia coli and Klebsiella spp. were screened for ESBL based on routine susceptibility testing results. Isolates with intermediate or resistant susceptibilities for extended spectrum cephalosporins or aztreonam were reported as probable ESBL producers. By using the NCCLS proposed ESBL confirmatory method, we tested 61 screen-positive isolates from 42 patients, 30 randomly selected susceptible isolates, and 12 isolates with previously characterized beta-lactamases. Ceftazidime contributed to 97% of screen-positive isolates, whereas aztreonam added a single patient isolate. An ESBL was confirmed in 86% of K. pneumoniae, 100% of K. oxytoca, and 20% of E. coli screen-positive single patient isolates. None of the susceptible isolates were shown to produce ESBL. Based on these findings a comment regarding the presence of ESBL seems sufficient for Klebsiella spp. but confirmatory testing is indicated for E. coli. 0.25 microg/mL was used to indicate the presence of ESBL, the specificity of the assay increased to 100%. The NCCLS ESBL phenotypic confirmatory method was reproducible and accurate enough to be used in the clinical laboratory.

Anti-Bacterial Agents↗

Individual characteristics and peer relations of psychiatrically hospitalized aggressive youths: implications for treatment.

OBJECTIVE: This study identified individual and peer-relations problems of inpatient youths who are aggressive, and whether youths who are aggressive in two settings have greater treatment needs than youths who are aggressive in one setting only. METHODS: 85 youths aged 10 to 16 years who were consecutively admitted to a psychiatric facility served as participants. Based on ratings by parents and hospital staff, youths were identified as aggressive in the community only, aggressive in the hospital only, aggressive in both settings, or nonaggressive. Dependent measures consisted of youth self-reports and ratings by parents and hospital staff. RESULTS: Youths who demonstrate aggressive behavior in two settings have more nonaggressive behavior problems, more disturbed peer relations, and more hostile thinking than do nonaggressive youths, and some youths, although they may behave aggressively during hospitalization, have similar treatment needs as nonaggressive youths. CONCLUSIONS: Mental health professionals who work with youths in psychiatric settings need to develop treatment plans that directly address the more severe externalizing problems, hostile thinking, and peer problems of aggressive youths over and above that of nonaggressive youths, and should be aware that youths who behave aggressively during hospitalization may not have problems more severe than those of nonaggressive youths.

Adolescent↗

The study of cutaneous melanomas in Camargue-type gray-skinned horses (1): clinical-pathological characterization.

The clinical and pathological characteristics of cutaneous melanomas occurring in Camargue-type gray-skinned horses are reported. Examination of 83 tumor-bearing horses revealed that the tumors occurred most frequently underneath the tail (93.9%) and at high rates in the peri-anal region (43.0%), the lips (33.0%), and the eyelids (24.0%), but rarely in the vulva (3.8%). Tumorous lesions were characterized by the presence of either hemispheric nodules or large infiltrated plaques, or their combinations. Microscopic examination indicated that tumorous lesions were composed mostly of melanocytes and numerous melanophages and that component cells manifested a remarkable cellular atypia with anisocytosis and anisokarinosis. Pathological examination of lesions corresponding to earlier stages of the tumors disclosed that tumor formation and its related melanogenesis occurred in close topographical association with apocrine sweat glands, but not at the dermal-epidermal junction. Larger nodules of the tumors were often composed of a concentric deposition of cell layers, each being separated by dermal components from the epidermis. Because of the absence of their tropism toward the epidermis and their multiloculation, horse melanomas are considered to be different in their pathological characteristics from human melanomas.

Animals↗

The study of cutaneous melanomas in Camargue-type gray-skinned horses (2): epidemiological survey.

An epidemiological survey was made on cutaneous melanomas occurring in Camargue-type, gray-skinned horses in southern France. The population investigated was composed of 264 horses, which were selected from the Camargue horse stud registry and were allowed to be examined by the owners. The presence of tumors was inspected macroscopically according to the standardized protocols of veterinary medicine specialists, and some tumors were subjected to macroscopic histopathological examination. The results indicated that: 1) the prevalence of melanomas in the overall population was 31.4%; 2) the odds ratio was obtained for an age class of 5-9 years, in which most melanomas were presumed to occur; 3) the incidence of melanomas was significantly correlated with age, giving a prevalence of 67% at ages > 15 years; 4) the size and number of tumorous lesions were significantly related to age; 5) little correlation was observed between melanoma incidence and gender; and 6) the most frequently occurring body site of these tumors was underneath the tail. Because of their frequent occurrence in shaded body regions, sun exposure was not likely to be a risk factor for melanoma formation in these horses. In view of the slightly darker skin pigmentation in these horses at younger ages, the unique characteristics of their melanocytes may be associated with melanoma formation.

Age Distribution↗

A urethral stent for the treatment of detrusor-striated sphincter dyssynergia.

OBJECTIVE: To assess the technique, efficacy and complications of the Ultraflex urethral stent (Boston Scientific Corp., Boston, MA) for the treatment of detrusor-striated sphincter dyssynergia (DSD). PATIENTS AND METHODS: Forty consecutive patients with DSD who had a Ultraflex stent placed in the membranous urethra were evaluated prospectively. DSD was caused by spinal cord injury in 30, multiple sclerosis in six and other neurological diseases in four. All patients were either tetraplegic or paraplegic and unable to use intermittent self-catheterization. Previous bladder management consisted of an indwelling catheter in 15 patients, chronic suprapubic catheters in two, intermittent catheterization in nine, and trigger reflex micturition in 14. The Ultraflex stent was placed under local anaesthesia. The stents were 50 mm long in 36 patients, 45 mm in two and 40 mm in two. The mean (SD) follow-up was 16.9 (13. 8) months. RESULTS: The mean (SD) residual urine decreased from 245. 9 (117) mL before stenting to 65.2 (19.3) mL at 12 months afterward (n = 19). One stent was removed at 13 months for chronic prostatic and urinary tract infection leading to autonomic dysreflexia. There was no stent stenosis and 17 of 18 stents had > 75% epithelial coverage at one year. None of the stents migrated. Seven patients underwent secondary bladder neck incision through the stent. The stent length was increased in four patients using a second overlapping distal stent, twice during the first procedure and twice within 6 months because the sphincter was inadequately covered. CONCLUSIONS: The Ultraflex stent achieved the expected results for a prosthetic sphincterotomy and appears to be an appropriate but less invasive treatment for DSD.

Adult↗

Development of resistance to chlorhexidine diacetate in Pseudomonas aeruginosa and the effect of a "residual" concentration.

Stable resistance in Pseudomonas aeruginosa NCIMB 10421 was obtained by step-wise exposure to gradually increasing concentrations of chlorhexidine diacetate (CHX). Repeated exposure to a proposed "residual" (sub-MIC) concentration of CHX also created stable resistance. Resistance was also developed by a single exposure to the "residual" concentration of CHX, but this was unstable. Similar experiments with Escherichia coli and CHX or cetylpyridinium chloride resulted in no significant increase in resistance. Antibiotic susceptibility profiles of the CHX-resistant P. aeruginosa cultures showed no cross-resistance, although some of the cultures were resistant to benzalkonium chloride.

Anti-Infective Agents, Local↗

Maternal risk factors for abnormal vascular coiling of the umbilical cord.

The objective of this paper is to identify maternal risk factors for abnormal vascular coiling of the umbilical cord. The umbilical cords of 657 neonates were examined and the coiling index determined by dividing the total number of complete vascular coils by the length of the cord in cm. Obstetrical history, delivery data, and neonatal outcome were also evaluated. The frequency distribution of umbilical coiling index was normal (10 th and 90th percentile and mean +/- SD = 0.17, 0.37, and 0.26 +/- 0.09 coils/cm, respectively). Maternal risk factors for abnormal vascular coiling were extremes of age for hyper-coiling, obesity, gestational diabetes mellitus, and preeclampsia for non-coiling. Hyper-coiled and non-coiled cords were significantly associated with adverse perinatal outcome (p < 0.001) and cesarean delivery (p < 0.0001). Neonates whose mothers are old or young, obese, diabetic, or have preeclampsia are likely to have hyper-coiled or non-coiled umbilical blood vessels.

Adult↗

The PC6B cytoplasmic domain contains two acidic clusters that direct sorting to distinct trans-Golgi network/endosomal compartments.

The mammalian proprotein convertases (PCs) are a family of secretory pathway enzymes that catalyze the endoproteolytic maturation of peptide hormones and many bioactive proteins. Two PCs, furin and PC6B, are broadly expressed and share very similar cleavage site specificities, suggesting that they may be functionally redundant. However, germline knockout studies show that they are not. Here we report the distinct subcellular localization of PC6B and identify the sorting information within its cytoplasmic domain (cd). We show that in neuroendocrine cells, PC6B is localized to a paranuclear, brefeldin A-dispersible, BaCl(2)-responsive post-Golgi network (TGN) compartment distinct from furin and TGN38. The 88-amino acid PC6B-cd contains sorting information sufficient to direct reporter proteins to the same compartment as full-length PC6B. Mutational analysis indicates that endocytosis is predominantly directed by a canonical tyrosine-based motif (Tyr(1802)GluLysLeu). Truncation and sufficiency studies reveal that two clusters of acidic amino acids (ACs) within the PC6B-cd contain differential sorting information. The membrane-proximal AC (AC1) directs TGN localization and interacts with the TGN sorting protein PACS-1. The membrane-distal AC (AC2) promotes a localization characteristic of the full-length PC6B-cd. Our results demonstrate that AC motifs can target proteins to distinct TGN/endosomal compartments and indicate that the AC-mediated localization of PC6B and furin contribute to their distinct roles in vivo.

Amino Acid Motifs↗

Factors associated with antiepileptic drug use among elderly nursing home residents.

UNLABELLED: BACKGROUND. Epilepsy, a chronic condition defined as two or more recurrent, unprovoked seizures, has the highest incidence at the end of life. Antiepileptic drugs (AEDs) are the primary therapeutic mode. Approximately 10%-11% of elderly nursing home residents receive one or more AEDs, a higher prevalence than would be expected in this age group. In the research literature, there is not a clear explanation of variations in AED use in nursing homes. The purpose of this study was to examine the prevalence and variations in use of AEDs by resident characteristics, AEDs used, drug dosage, and AED combinations in treatment regimens. METHODS: This was a retrospective, cross-sectional study of residents (N = 21,551) in a convenience sample of nursing homes in 24 states and the District of Columbia. The unit of analysis was the individual resident. The study period was a single day in 1995. Bivariate and multivariate analyses were used to test differences. RESULTS: The prevalence of AED use was 10.5% across all elderly residents. In a multivariate analysis, factors associated with AED treatment included seizure indication, age group, and geographic region. AED use by age group showed declining use as the residents aged, from 65-74 to 75-84 to > or =85 years. CONCLUSIONS: The inverse relationship between AED use and age group was unexpected because the incidence of epilepsy increases with advancing age. This finding raises important questions about the future use of these drugs in elderly nursing home residents.

Aged↗

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Journal Article↗

F.I.GU.R.E.: facial idiopathic granulomas with regressive evolution. is 'lupus miliaris disseminatus faciei' still an acceptable diagnosis in the third millennium?

We report the case of a 69-year-old woman who presented a papular eruption on the eyelids. Histological features revealed a tuberculoid granuloma with a central caseating necrosis. Laboratory and radiological investigations revealed no tuberculosis and no systemic granulomatosis. Absence of vascular symptoms, inefficiency of cyclines and histopathological findings excluded granulomatous-type rosacea. Lupus miliaris disseminatus faciei (LMDF) was our final diagnosis. On the basis of our findings and a literature review, we believe that LMDF is an entity distinct from either skin tuberculosis or granulomatous-type rosacea. However, its name is confusing, and we propose to change it to 'facial idiopathic granulomas with regressive evolution (FIGURE)'.

Aged↗

Is the acetazolamide test valid for quantitative assessment of maximal cerebral autoregulatory vasodilation? An experimental study.

BACKGROUND AND PURPOSE: The cerebral vasodilating effect of acetazolamide (ACZ) injection has been used as an index of the autoregulatory vasodilation (or cerebral perfusion reserve). The question of whether the ACZ test assesses the maximal autoregulatory vasodilating capacity is not definitely resolved. The effects of ACZ injection on this reserve at a dose producing maximal vasodilation have never been evaluated and may help to resolve this problem. METHODS: The effect of ACZ injection on cerebral blood flow (CBF) autoregulation was tested in anesthetized rats. A pilot experiment evaluated the dose-effect relationship of injected ACZ, cumulative doses (n=4, group 1), and independent bolus doses (n=6, group 2). CBF was estimated by laser-Doppler flowmetry, and cerebrovascular resistance (CVR) was calculated from mean arterial blood pressure (MABP) and from CBF (expressed as a percentage of baseline CBF). A bolus of ACZ of 21 mg/kg produced the maximal cerebral vasodilation that could be obtained by ACZ administration. In the main experiment, MABP was lowered from 110 to 20 mm Hg by stepwise bleeding in 3 groups of 6 animals treated 10 minutes before bleeding by injection of saline (group 3), 7 mg/kg ACZ (group 4), or 21 mg/kg ACZ (group 5). RESULTS: The CVR-MABP relationship was linear in all groups, indicating that CBF autoregulation was still effective after ACZ administration. CONCLUSIONS: These results indicate that maximal ACZ-induced cerebral vasodilation is not quantitatively equivalent to maximal autoregulatory vasodilating capacity in anesthetized rats.

Acetazolamide↗

Placental leptin.

Placental tissues from humans, rodents and farm animals contain leptin and its receptor. Leptin produced by the human placenta has the same size, charge and immunoreactivity as leptin produced by adipose tissue. However, the expression of human placental leptin appears to be regulated by a placenta-specific upstream enhancer. In this review the occurrence of leptin and its receptor in a range of species and placental types is described, and its significance during pregnancy discussed. Placental leptin contributes to the increase in maternal circulating concentrations of leptin during late pregnancy when it is likely to have an endocrine role in regulating maternal energy balance. Placental leptin may have angiogenic and immunomodulatory activities, which affect the placenta in an autocrine or paracrine manner. It also appears to affect fetal growth and development by binding to leptin receptors present in fetal organs.

Adipose Tissue↗

Efficacy of nerve root versus interspinous injections of glucocorticoids in the treatment of disk-related sciatica. A pilot, prospective, randomized, double-blind study.

STUDY OBJECTIVES: Pilot study comparing the short-term efficacy on pain and functional impairment of nerve root sheath versus interspinous glucocorticoid injections in patients admitted to a French rheumatology department for disk-related sciatica or femoral neuralgia. PATIENTS AND METHODS: Thirty patients with refractory nerve root pain (sciatica, n = 29; femoral neuralgia, n = 1) for a mean of four months were randomized to nerve root injection (n = 17) or interspinous injection (n = 13) of the same mixture of 0.10 g of lidocaine hydrochloride and 3.75 mg of cortivazol. Both injection methods were performed under analgesia and benzodiazepine sedation to maintain double blinding. Each patient was evaluated daily during the first seven days of bed rest in the hospital, then after discharge on postinjection day 28. RESULTS: Prompt pain relief was obtained in both groups. On day 1, the mean pain scale score (0-100) fell from 70 +/- 3.9 to 26 +/- 5.6 in the nerve root group and from 63 +/- 4 to 23 +/- 4.7 in the interspinous group. These results were sustained on D7 and D28. CONCLUSIONS: The unusually high level of efficacy of glucocorticoid injection in our study may be ascribable in part to strong placebo and Hawthorne effects and in part to the intrinsic effects of the injections. Whether nerve root injection is superior over interspinous injection remains unproven.

Adult↗

The development of retinal ganglion cell dendritic stratification in ferrets.

A signature feature of mature ferret retinal ganglion cells (RGCs) is the stratification of their dendrites within either ON or OFF sublayers of the retinal inner plexiform layer (IPL). Dendritic stratification is achieved through the gradual restriction of RGC dendrites which initially ramify throughout the IPL. We examined the time course of stratification by retrogradely labeling ferret retinas with DiI at various postnatal ages. Stratification of beta and alpha RGC dendrites into either the ON or OFF sublayers of the IPL begins around postnatal day 5, when class-specific morphologies begin to emerge, and is largely completed by eye opening, at the end of the first postnatal month. Our results imply that dendritic stratification of ferret ON and OFF RGCs, as in other mammals, occurs independently of visually driven activity.

Aging↗

Structure-activity relationships of omega-conotoxins MVIIA, MVIIC and 14 loop splice hybrids at N and P/Q-type calcium channels.

The omega-conotoxins are a set of structurally related, four-loop, six cysteine containing peptides, that have a range of selectivities for different subtypes of the voltage-sensitive calcium channel (VSCC). To investigate the basis of the selectivity displayed by these peptides, we have studied the binding affinities of two naturally occurring omega-conotoxins, MVIIA and MVIIC and a series of 14 MVIIA/MVIIC loop hybrids using radioligand binding assays for N and P/Q-type Ca2+channels in rat brain tissue. A selectivity profile was developed from the ratio of relative potencies at N-type VSCCs (using [125I]GVIA radioligand binding assays) and P/Q-type VSCCs (using [125I]MVIIC radioligand binding assays). In these peptides, loops 2 and 4 make the greatest contribution to VSCC subtype selectivity, while the effects of loops 1 and 3 are negligible. Peptides with homogenous combinations of loop 2 and 4 display clear selectivity preferences, while those with heterogeneous combinations of loops 2 and 4 are less discriminatory. 1H NMR spectroscopy revealed that the global folds of MVIIA, MVIIC and the 14 loop hybrid peptides were similar; however, several differences in local structure were identified. Based on the binding data and the 3D structures of MVIIA, GVIA and MVIIC, we have developed a preliminary pharmacophore based on the omega-conotoxin residues most likely to interact with the N-type VSCC.

Amino Acid Sequence↗