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Biomedical subjects

J Davidson

Publications and source records attributed to J Davidson.

At least 55 records · Page 3Linked to original sources

Nefazodone in post-traumatic stress disorder: results from six open-label trials.

Nefazodone, an antidepressant which blocks serotonin (5-HT)2 receptors and 5-HT reuptake, was evaluated in the treatment of post-traumatic stress disorder (PTSD) in six open-label studies involving both civilians and combat veterans. Our objective was to report this available pooled data to characterize the response of this drug in PTSD. Specifically, we looked at response rates using three different criteria, the effect of nefazodone on each PTSD cluster and individual symptoms and, lastly, variables that might predict response. One hundred and five outpatients with chronic PTSD were treated with nefazodone titrated up to 600 mg/day, 92 of whom were entered in an intent to treat analysis. We used the percentage drop in score between baseline and endpoint on main scale as a common measure to evaluate outcome. The response criterion of a drop in score of at least 30%, 40% and 50% revealed response rates of 46, 36 and 26%, respectively. Nefazodone showed a broad spectrum of action on PTSD symptoms. This profile might make nefazodone a useful drug to treat PTSD. Predictors of response include age, sex and trauma type. Double-blind, placebo-controlled clinical trials in PTSD are in progress to assess the utility of nefazodone as a treatment in this disorder.

Adult↗

Extracranial drainage of cerebrospinal fluid: a study of beta-transferrins in nasal and lymphatic tissues.

OBJECTIVE: To determine whether an alternative route of cerebrospinal fluid (CSF) drainage exists through the nasal mucosa and the cervical lymphatic system. STUDY DESIGN: A prospective study was carried out on 18 patients at a university teaching hospital. METHODS: Ten patients undergoing routine endoscopic sinus surgeries and eight patients undergoing neck dissections were recruited for this study. Tissues were sampled from the middle turbinate, nasopharynx, and upper septum in the first group; jugulodigastric lymph nodes and nasopharyngeal tissues were obtained from the second group. Specimens were subjected to immunofixation electrophoresis in an attempt to identify the presence of beta-1 and beta-2 transferrins. Serum samples were obtained from each subject to serve as controls. RESULTS: All tissue specimens contained beta-1 transferrin; none showed evidence of beta-2 transferrin. CONCLUSION: Using this technique, an alternate route of CSF drainage through the nose and the cervical lymphatic system could not be confirmed. Nevertheless, a new technique of performing immunofixation in solid tissues for the purpose of beta-transferrin identification is described.

Cerebrospinal Fluid Rhinorrhea↗

Endoscopic orbital decompression with preservation of an inferomedial bony strut: minimization of postoperative diplopia.

With the increasing sophistication and safety of endoscopic orbital decompression, the technique is seen by many as an attractive and less morbid alternative to traditional open techniques. This rationale also makes the procedure more acceptable for individuals considering decompression for cosmetic reasons. As a result, complications such as postoperative diplopia assume greater significance. Preservation of an inferomedial bony strut has been postulated to reduce the incidence of postoperative diplopia in transconjunctival, but not endoscopic, orbital decompression for dysthyroid ophthalmopathy. We present a consecutive series of 11 subjects (21 eyes) who underwent transnasal endoscopic medial and inferior decompression of the orbits bilaterally. All patient charts were reviewed in a retrospective fashion and ophthalmologic, surgical, and cosmetic data were recorded, with callback of patients with incomplete data sets. All cases were performed under general anaesthesia. Preservation of the strut was possible in 15 of 21 eyes. Visual acuity was preserved or improved in all 21 eyes. Average ocular recession based on Hertel measurements was 3.6 mm and there were no surgical complications. New-onset or worsening diplopia was noted postoperatively in 2 of 11 subjects. However, in patients where both struts were preserved, there was zero incidence of postoperative diplopia (0/6). These results indicate that preservation of an inferomedial bony strut is not only technically feasible but also does not compromise the adequacy of decompression. The results also suggest that preservation of the inferomedial bony strut during endoscopic orbital decompression can reduce the incidence of postoperative diplopia.

Chi-Square Distribution↗

Development of the Royal Marsden Hospital paediatric oncology quality of life questionnaire.

Our objective was to develop a health-related quality of life measure for use in pediatric oncology. The development process followed the EORTC Quality of Life Study Group (QLSG) guidelines but utilized a parental proxy rating methodology developed within the framework of the EORTC QLSG. Data are reported on the preliminary stages of development, which include interviews in the target population, specialist review of questionnaire content and initial results on the psychometric structure of the measure. The questionnaire has been translated from English to Swedish and Dutch and is available for international field testing. Suggestions for further development of the new measure are described, including the need for parallel forms for use with children and adolescents as well as the parental proxy rating form described here.

Child↗

Evaluation of adjuvant psychological therapy in patients with testicular cancer: randomised controlled trial.

OBJECTIVE: To determine the efficacy of adjuvant psychological therapy in patients with testicular cancer and to compare the characteristics and psychosocial outcomes of men who agreed to participate with those who declined to participate in a randomised trial of psychological intervention. DESIGN: Newly diagnosed patients were asked to participate in a randomised trial of psychological support compared with standard medical care. Participants and non-participants completed self assessment questionnaires at baseline and at 2, 4 and 12 months. SETTING: Testicular Tumour Unit of the Royal Marsden Hospital. SUBJECTS: 73 of 184 (40%) eligible patients agreed to enter the randomised trial (participants) and 81 (44%) declined to participate but agreed to complete further assessments (non-participants). 30 patients wanted no further contact with the researchers. OUTCOME MEASURES: Hospital anxiety and depression scale, psychosocial adjustment to illness scale, Rotterdam symptom checklist, mental adjustment to cancer scale. Only scores on the hospital anxiety and depression scale are reported for evaluating treatment efficacy. RESULTS: 111 of 184 (60%) eligible men declined to participate in the trial. Patients with stage I disease were most likely to refuse to participate. A patient was less likely to participate if he had low volume disease and was receiving no further treatment. Likelihood of participation was associated with stage of disease and with type of primary treatment (P < 0.001 for heterogeneity). Patients with early stage disease (P < 0.001) and fewer physical symptoms (P < 0.001) were less likely to participate. Psychosocial factors associated with participation included anxious preoccupation regarding disease (P = 0.01). There were no differences in outcome between participants and non-participants during follow up. Patients seemed to gain little benefit from adjuvant psychological therapy. At 2 months change from baseline favoured the treated group in the anxiety subscale (mean difference between groups -1.41 (95% confidence interval -2.86 to 0.03)). This was not sustained when adjusted for factors related to the disease. By 12 months change from baseline seemed to favour the control group (mean difference between groups 1.66 (-0.18 to 3.50)). CONCLUSIONS: Patients with testicular cancer seem to have considerable coping abilities. Those who declined to participate in the trial differed from those who participated. Those who agreed to participate may comprise the clinical group who perceive a need for psychological support. No evidence was found to indicate a need for routinely offering adjuvant psychological therapy.

Adolescent↗

The effectiveness of the routine clinic visit in the follow-up of breast cancer patients: analysis of a defined patient cohort.

The study aimed to identify the proportion of patients with relapse or a contralateral breast tumour who are diagnosed as a consequence of regular follow-up in a specialist breast clinic after breast conserving surgery and radiotherapy for early breast cancer. A retrospective review was undertaken of 490 consecutive patients entered into a randomized clinical trial of radiotherapy fractionation at a single institution. As part of the trial, patients were reviewed in a multidisciplinary breast clinic 3-monthly for the first 3 years, 6-monthly between 3 and 5 years and annually thereafter, with biennial mammography. For this study, information was retrieved from hospital records to ascertain: (a) whether patients were symptomatic at the time of relapse or contralateral breast tumour; and (b) whether they presented at a scheduled appointment or brought their appointment dates forward. The subsequent management of patients with relapse was reviewed to determine whether or not this may have been influenced favourably by a policy of regular follow-up. Twenty-one (44%) of the 48 patients with locoregional relapse were asymptomatic. Of these, 17 were detected by clinical examination (that is, directly as a result of a routine clinic attendance), while four were detected by routine mammography. Ten of the 17 patients diagnosed by clinical examination had successful surgery for locoregional relapse and all have remained disease free. Five of 17 developed distant metastases within 6 months and two others had skin nodules on the breast excised. Only three of the 67 patients with distant relapses were asymptomatic. Two of the 11 patients with contralateral breast tumours were asymptomatic and were diagnosed on routine mammography. The benefits and cost-effectiveness of less rigid approaches to follow-up of breast cancer patients needs to be evaluated in large prospective randomized trials.

Adult↗

Prostaglandin and fatty acid modulation of Escherichia coli O157 phagocytosis by human monocytic cells.

Phagocytosis by human monocytes is an important primary survival mechanism particularly during bacterial infection. However, the processes that control the events and mediators involved in the activation of monocytes and their impact on the phagocytosis of bacteria are poorly understood. The effect of bacterial endotoxin, interleukin-1 beta (IL-1 beta), fatty acids and prostaglandin E2 (PGE2) on the phagocytosis of fluoroscein isothiocyanate (FITC)-labelled Escherichia coli (O157) by human blood monocytes and U937 cells was studied by flow cytometry. Endotoxin increased the phagocytosis of labelled bacteria by both monocytes and U937 cells. IL-1 beta and the polyunsaturated fatty acids; dihomo-gamma-linolenic and arachidonic acids also increased the phagocytic activity of both monocytes and U937 cells. In contrast, PGE2 suppressed phagocytosis in a concentration-dependent manner. The cyclo-oxygenase inhibitor, ketoprofen, further enhanced the increased phagocytic activity in the presence of endotoxin and interleukin-1 (IL-1) indicating suppression by endogenous prostaglandins. This was confirmed by the data which showed that lipopolysaccharide (LPS) and IL-1 increased PGE2 release and ketoprofen inhibited release. Endotoxin and fatty acids increased IL-1 beta release also, whereas PGE2 inhibited release. The data suggest that phagocytic activity may be linked to changes in IL-1 levels. The data presented in this study also suggest that monocyte phagocytosis in the course of bacterial infection would be altered during pathophysiological events which result in elevation of extracellular fatty acids.

Cell Culture Techniques↗

Microsurgical replantation of the lip: a multi-institutional experience.

Traumatic amputation of the lip is a rare yet devastating event affecting both form and function. Considering the available methods for reconstruction, replantation may offer a reasonable solution. We sought to characterize the variables associated with lip replantation and to assess the outcome in a retrospective review of 13 lip replantations performed in 12 institutions utilizing a form database and clinical and photographic analysis. Lip replantation was successful in all 13 patients; partial flap loss occurred in one patient owing to iatrogenic injury. Follow-up averaged 3.1 years. Average patient age at the time of injury was 21.1 years. There were six male and seven female patients. Injuries in two patients were the result of a human bite, the remaining injuries resulted from dog bites. One patient had significant associated injuries. Average length of hospital stay was 11.9 days. Ten patients suffered amputations of the upper lip, and three suffered amputations of the lower lip. Average defect size was 10.6 cm2. Operative time averaged 5.7 hours (range 2.5 to 12 hours). Warm ischemia time averaged 2.9 hours, and cold ischemia time averaged 2.7 hours. Donor and recipient veins were often scarce; all patients had at least one arterial anastomosis, whereas no vein was available in 7 of 13 patients; vein grafts were required in one patient. Leech therapy was employed in 11 of 13 patients. Anticoagulant therapy was administered in the majority of patients. Systemic heparin was utilized in 10 of 13 patients, low molecular weight dextran was used in 7 of 13 patients, and aspirin was given to 7 of 13 patients. One bleeding complication was incurred. An average of 6.2 units of packed red blood cells was administered to 12 of 13 patients (adjusted to 250 cc/unit). Antispasmodic therapy was employed in six of eight patients intraoperatively and in two of eight patients postoperatively. Intraoperative complications included difficulty identifying veins in 7 of 13 patients, arterial spasm in 1 of 13 patients, and vessel diameter < 0.5 mm in 4 patients. Postoperatively, one patient suffered vein thrombosis requiring anastomotic revision. Broad spectrum antibiotics were administered to all patients, and there were no infections. Nearly one-third (4 of 13) patients suffered prolonged edema lasting > 4 months. Color match of the replanted lip segment was rated excellent in all cases. Hypertrophic scarring occurred in 6 of 13 patients. A total of 12 revision procedures was performed in six patients. Interestingly, leech therapy resulted in permanent visible scarring as a result of the leech bite in 6 of 11 patients treated. Ten patients demonstrated active orbicularis muscle contraction in the replanted lip segment. Stomal continence was present in all lips. Sensibility return in the replanted lip segment was quite good with 12 of 13 patients demonstrating at least protective moving two-point sensibility (> or = 10 mm). Partial replant necrosis in one patient resulted in significant scar and contraction that compromised the aesthetic appearance. Overall, however, all patients were uniformly pleased with their final results. This clinical study is one of the largest of its kind on lip replantation. Although this represents a multi-institutional experience, the data are remarkably consistent. Re-establishment of venous outflow seems to be the most problematic technical challenge. By incorporating the adjuncts of anticoagulation, leech therapy, and antispasmodics, a successful outcome can be expected despite the paucity of vessels and small vessel size. The risks of blood transfusion, lengthy operative time, and hospital stay must be weighed against the functional benefits.

Adolescent↗

Blindness as a complication of Le Fort osteotomies: role of atypical fracture patterns and distortion of the optic canal.

Blindness in patients suffering maxillofacial trauma is usually caused by optic nerve or optic canal injuries. It is, however, an uncommon complication of facial trauma, with a reported incidence of only 3 to 5 percent. This incidence drops dramatically when fractures are performed in the controlled situation of orthognathic surgery. Given the rarity of ophthalmic complications after traumatic Le Fort I injuries, it is not surprising that few cases have been reported after orthognathic surgery. In this article, three cases of visual loss or skull base injury after elective Le Fort I osteotomy are described. All of these cases were presumably straightforward surgically and were performed by experienced surgeons. The literature is reviewed and the pathomechanics of each injury are experimentally explored in a cadaver model. To determine the presence of increased pressure on the optic nerve, optic canal deformation, or fractures extending to the skull base, two separate experiments were devised. In the first experiment, a pressure transduction system was used to document any significant forces that may be directly transmitted to the contents of the optic canal during pterygomaxillary separation. Then tested was the hypothesis that a stepped or tapered osteotomy will allow for a more predictable pterygomaxillary fracture. One of five cadaver specimens in group 1 demonstrated a transient increase in the right optic canal pressure during down-fracture of the maxilla. This change was less than 10 mmHg, and its duration was less than 5 seconds. The canal pressure returned to baseline with the completion of the fracture. In group 2, there was no documented pressure change with either osteotomy technique. Of note, in group 2, all specimens undergoing standard Le Fort osteotomy demonstrated uncontrolled propagation of the fracture lines superiorly in the pterygoid bones. The uncontrolled and unpredictable nature of pterygomaxillary disjunction may result in the extension of fractures to the skull base or the generation of deforming forces to the optic canal may compress or injure the optic nerve and its circulation. It is proposed that a stepped or tapered osteotomy will generate a more controlled pterygomaxillary separation during orthognathic surgery and may reduce the risk of devastating ophthalmologic complications.

Adolescent↗

Family history of breast cancer: what do women understand and recall about their genetic risk?

The current study has two aims: (1) to look at people's recall of risk information after genetic counselling and (2) to determine the impact of receiving an audiotape of the genetic consultation on level of recall, cancer related worry, and women's uptake of risk management methods. Using a prospective randomised controlled design, subjects receiving an audiotape were compared with a standard consultation group. Participants were drawn from attenders at the genetic clinics of two London hospitals and included 115 women with a family history of breast cancer. Assessment of perceived genetic risk, mental health, cancer worry, and health behaviour was made before counselling at the clinic (baseline) and by postal follow up. Usefulness of audiotapes and satisfaction with the clinical service was assessed by study specific measures. The data indicate that cancer worry is reduced by provision of an audiotape of the genetic consultation. Recall of the genetic risk figure, however, is not affected by provision of an audiotape and neither is it related to women's overall perception of being more or less at risk of breast cancer than the average woman. Forty-one percent of women accurately recalled their personal risk of breast cancer at one month follow up; however, 25% overestimated, 11% underestimated, and 23% could not remember or did not know their breast cancer risk. Recall of the risk figure is more accurate when the clinical geneticist has given this to the woman as an odds ratio rather than in other formats. Subsequent health behaviour is unaffected by whether women have an audiotape record of their genetic consultation. Results suggest that having a precise risk figure may be less important than women taking away from the consultation an impression that something can be offered to help them manage that risk. Provision of an audiotape of the consultation is of limited usefulness. The need for psychological care to be better integrated into genetic counselling at cancer family clinics was highlighted by the study. The results are discussed in terms of future service development.

Breast Neoplasms↗

A bridging study of fananserin in schizophrenic patients.

Fananserin is a potential antipsychotic compound with high affinity for both D4 and 5-HT2A receptors, and negligible affinity for D2 receptors. Because the tolerance for antipsychotic compounds often differs between schizophrenic patients and healthy subjects, this bridging study was designed to evaluate the tolerability of fananserin, to define the slow titration maximum tolerated dose in the target population, and to identify the most rapid well-tolerated rate of titration for this compound. Three rates of titration regimens were examined in a total of 26 schizophrenic patients in a parallel group design, following a 3-day placebo washout period from previous antipsychotic medication. The slow rate of titration (reaching the maximum dose of 600 mg/day in 16 days with 100-mg increases every 3 days) was well tolerated, but a rapid titration schedule (reaching 600 mg/day in 8 days with 200-mg increases every 3 days) resulted in hypotension in 3 of 6 patients and termination of the group on Day 10. An intermediate rate of titration (reaching 600 mg/day in 10 days with 100-mg increases every 2 days) was then examined and was well tolerated, with transient episodes of mild hypotension reported in 2 of 10 patients. Thus, although hypotension was identified as the dose-limiting adverse event in this study, a reduction in the titration rate was effective in reducing the incidence and severity of this side effect. In this study, schizophrenic patients administered multiple doses of fananserin tolerated doses 400 percent greater than the maximum tolerated single dose in healthy volunteers.

Adolescent↗

Intra-aortic balloon pump: indications and complications.

Results obtained with intra-aortic balloon pumps (IABPs) at Harbor-UCLA Medical Center from 1990 to 1995 were reviewed to analyze the indications for its use as well as the incidence and types of vascular complications that occurred. Of 86 patients (53 men and 33 women) in whom pumps were used, 66 underwent coronary bypass, 14 underwent valve replacement, and 6 underwent both coronary bypass/valve replacement. Thirteen (15%) deaths occurred (8 coronary bypass patients, 4 valve replacement patients, and 1 coronary bypass/valve replacement patient). The indications for IABP were broadly classified as prophylactic or inability to wean. Prophylactic IABP placement preoperatively occurred in 35 (41%) patients for profound ventricular dysfunction (27 patients), compelling coronary anatomy including critical left main disease (7 patients), and unstable angina (1 patient). Inability to wean occurred in 51 (59%) patients. Three patients (3.5%) developed major vascular complications resulting in limb ischemia. All three underwent thrombectomies, fasciotomies, and above-knee amputations; two patients subsequently died. Vascular reconstruction was performed in two patients as a direct result of their vascular process. All three vascular complications occurred in women. Besides gender, there was no difference between IABP patients with or without vascular complications in terms of age or presence of diabetes, hypertension, smoking history, obesity, or known peripheral vascular disease. These results indicate that IABPs are effective both prophylactically and intraoperatively in patients who would not otherwise survive cardiac surgery.

Coronary Artery Bypass↗