Biomedical subjects
Publications and source records attributed to S Thomas.
Gonioscopy forms part of a complete ophthalmic examination and is mandatory for the diagnosis and management of glaucoma. Gonioscopy permits identification of eyes at risk for closure and detects angle abnormalities that could have diagnostic and therapeutic implications. The technique of gonioscopy, its value in management, and guidelines for routine use are discussed in this paper.
Family history of hypertension (positive and negative) and gender groups were compared on cardiovascular responses at rest, during stressors and during recovery. Two tasks were employed, mental arithmetic and an anger recall interview. Both levels and reactivity measures of blood pressure, heart rate, cardiac output and total peripheral resistance were included. In addition, participants filled out several questionnaires measuring state feelings during the task and recovery periods, trait anger/hostility and emotions. Both men and women with a positive family history of hypertension exhibited higher tonic levels of blood pressure and heart rate at rest, recovery and during both tasks. They also exhibited greater heart rate reactivity during the mental arithmetic task and greater blood pressure reactivity to both tasks when post-math recovery, but not initial rest, was used as a covariate. Positive family history individuals reported less trust and gregariousness, more depression and aggression, less awareness of somatic responses to the tasks and less effort to relax during the post-task rest periods. Finally, significant correlations were found between low anger expression how anger experience and high anger control and task SBP levels in positive family history individuals.
Explore the source record for details and available documents.
Multiple primary cancers are being reported with increasing frequency in recent years, the frequency varying from 0.3 to 4.3% in different studies. A combination of primary cancer of larynx and lung is the most common followed by malignant neoplasm involving lip-larynx, skin-larynx, skin-lung, breast-ovary and breast-endometrium. Two interesting cases of rare combinations of primary cancers are being presented. In the first case primary adenocarcinoma of the gall bladder was associated with appendiceal adenocarcinoma. In the second case primary malignant papillary serous cystadenocarcinoma of right ovary and squamous cell carcinoma of cervix uteri were found.
BACKGROUND: The tradition of routine, long-term follow-up of cancer patients in the outpatient clinic has led to busy clinics and long waiting times. Many cancer patients are anxious and have become dependent on the specialist clinic for reassurance. General practitioners (GPs) have been shown to be willing to assume greater responsibility for the routine follow-up of breast cancer patients, but patients have demonstrated a preference for hospital follow-up. If patients are discharged unwillingly, their rehabilitation may be at the cost of an increased demand on GP practices. AIM: To determine the consequences for GPs of discharging long-term cancer patients from a hospital outpatient follow-up clinic. METHOD: A consecutive sample of 65 patients under annual review in a hospital oncology clinic were offered a planned discharge in which their return to the clinic, if necessary, was guaranteed. The 41 patients who accepted discharge were monitored. Anxiety and depression rates were assessed using the Hospital Anxiety and Depression Scale (HADS) at the time of discharge and four months later at a home interview. The GPs of all patients who were discharged were sent questionnaires four and twelve months after discharge to evaluate consultation rates and change in psychological morbidity. RESULTS: The results showed no significant increase in the consultation rates during the 12 months after discharge compared with the previous 12 months. There was no significant change in the level of patients' anxiety or depression at four months after discharge. The great majority of GPs (71%) reported no change in their perception of patients' levels of anxiety or depression. GPs thought there was a need for more specialist Macmillan nurses working in the community and highlighted the importance of fast-track specialist referral. CONCLUSION: Discharging this group of long-term cancer survivors did not increase the workload of GPs. However, GPs' concern over the lack of availability of Macmillan nurses in the community suggests that primary care services may find it difficult to cope adequately with the special requirements involved in cancer patient care. Finally, there is a need to address the further training requirements of GPs in the routine follow-up of cancer patients.
It is difficult to hold a pair of loose prisms in one hand. Doing so can lead to inaccuracy, which worsens with large-angle exotropia or vertical deviations. The authors applied a self-adhesive hooked Velcro (Velcro Sticky Back Tape, Velcro USA Inc., Manchester, NH) strip to the base and the top of loose prisms. They applied the complementary looped Velcro to a wooden bar. As a result, a pair of prisms could be suspended horizontally and/or vertically while being held in one hand. Forty consecutive patients undergoing strabismus surgery without adjustable sutures were retrospectively studied to evaluate the accuracy of this method. Clinical use confirmed its ease and convenience. Of 19 patients with exotropia and 15 patients with esotropia (mean ages 41.9 and 15.7 years, respectively; mean deviations 44.7 and 49.8 D, respectively), 4 patients with abducens paralysis, and 2 patients with trochlear palsies, 1 surgery achieved less than 10 D of residual deviation in all but 2 (5.9%). This simple, inexpensive system can assist with the clinical evaluation of ocular deviation.
Several signal transduction pathways have been implicated in the mechanism of protection induced by ischemic preconditioning (PC). For example, stimulation of a variety of G-protein coupled receptors results in stimulation of protein kinase C (PKC) which has been suggested to act as common denominator in eliciting protection. PC also significantly attenuated cAMP accumulation during sustained ischemia, suggesting involvement of an anti-adrenergic mechanism. The aim of this study was to evaluate the beta-adrenergic signal transduction pathway (as evidenced by changes in tissue cAMP and cAMP- and cGMP-phosphodiesterase) during the PC protocol as well as during sustained ischemia. Isolated perfused rat hearts were preconditioned by 3 x 5 min global ischemia (PC1,2,3) interspersed by 5 min reperfusion, followed by 25 min global ischemia. Tissue cAMP- and cGMP-PDE activity as well as cAMP and cGMP levels were determined at different time intervals during the PC protocol and sustained ischemia. Tissue cAMP increased with each PC ischemic event and normalized upon reperfusion, while PDE activity showed the opposite, viz a reduction during ischemia and an increase during reperfusion. Except for PC1, tissue cGMP showed similar fluctuations. Throughout 25 min sustained ischemia, cAMP- and cGMP-PDE activities were higher in PC than in nonpreconditioned hearts, associated with a significantly lesser accumulation in cAMP and higher cGMP levels in the former. Fluctuations in cyclic nucleotides during preconditioning were associated with concomitant changes in PDE activity, while the attenuated beta-adrenergic response of preconditioned hearts during sustained ischemia may partially be due to increased PDE activity.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Hemodynamic abnormalities have been implicated in the pathogenesis of the increased glomerular permeability to protein of diabetic and other glomerulopathies. Vascular permeability factor (VPF) is one of the most powerful promoters of vascular permeability. We studied the effect of stretch on VPF production by human mesangial cells and the intracellular signaling pathways involved. The application of mechanical stretch (elongation 10%) for 6 h induced a 2.4-fold increase over control in the VPF mRNA level (P < 0.05). There was a corresponding 3-fold increase in VPF protein level by 12 h (P < 0. 001), returning to the baseline by 24 h. Stretch-induced VPF secretion was partially prevented both by the protein kinase C (PKC) inhibitor H7 (50 microM: 72% inhibition, P < 0.05) and by pretreatment with phorbol ester (phorbol-12-myristate-13 acetate 10(-)7 M: 77% inhibition, P < 0.05). A variety of protein tyrosine kinase (PTK) inhibitors, genistein (20 microg/ml), herbimycin A (3.4 microM), and a specific pp60(src) peptide inhibitor (21 microM) also significantly reduced, but did not entirely prevent, stretch-induced VPF protein secretion (respectively 63%, 80%, and 75% inhibition; P < 0.05 for all). The combination of both PKC and PTK inhibition completely abolished the VPF response to mechanical stretch (100% inhibition, P < 0.05). Stretch induces VPF gene expression and protein secretion in human mesangial cells via PKC- and PTK-dependent mechanisms.
1. The nystatin-perforated whole-cell recording mode of the patch-clamp technique was used to investigate the membrane conductance of trout (Oncorhynchus mykiss) red blood cells in the steady state, 5 min after exposure to hyposmotic medium and 10 min after return to normal isosmotic medium. 2. Whole-cell I-V relations showed outward rectification when red blood cells were bathed in isosmotic (320 mosmol l-1) saline solution and the patch pipette was filled with 117 mM KCl. The membrane conductance was 2.58 +/- 0.59 nS (number of experiments, n = 18) between 0 and 100 mV and 1.32 +/- 0.19 nS (n = 18) between 0 and -100 mV. Removal of Cl- from the extracellular side or incubation with the Cl- channel blocker DIDS caused a reduction in whole-cell membrane conductance by more than 50%, indicating that the membrane current was generated by Cl- ions. The remaining conductance was voltage independent and probably due to non-selective cation conductance. 3. The membrane conductance increased approximately 2-fold after cell swelling induced by exposure to hyposmotic saline solution (215 mosmol l-1). This effect was abolished in Cl(-)-free hyposmotic medium or in the presence of DIDS. 4. The return to isosmotic solution produced a fall in membrane conductance to, or below, control values. 5. We conclude that trout red blood cells possess a significant Cl- conductance in the steady state which is reversibly activated during cell swelling and contributes to volume recovery.
Previous chromosomal analyses related to human aging used mainly cross-sectional data on metaphase chromosomes. However, it is difficult to directly relate the cross-sectional results to the specific type(s) of chromosomal mutations possibly occurring within a specific individual with advancing age, because the unique genetic endowment of each individual for longevity might be a modulating factor. We therefore have performed, for the first time, a longitudinal study of both numerical and structural chromosome analyses of skin fibroblasts at interphase and at metaphase derived from eight donors participating in the Baltimore Longitudinal Study. We have used the FISH method with chromosome-specific DNA probes and the data on total aneuploidy of 17 different chromosomes in each of the 16 cell cultures (2 from each of eight individuals) indicate that significantly higher percentages of aneuploid cells are detected at interphase than at metaphase. Mostly, the levels of chromosome-specific aneuploidy increase with the donor's advancing age and, in most individuals, chromosomes 1, 4, 6, 8, 10, and 15 show significantly higher frequencies of aneuploidy at interphase than those of the 11 other chromosomes studied. Although the significance of relatively higher levels of aneuploidy of certain chromosomes with aging remains unclear, it is intriguing to note that some of these chromosomes, such as 1, 4, and 6, have already been assigned to harbor senescence genes and chromosome 8 is known to house the gene for Werner Syndrome (progeroid syndrome), which shows very limited proliferative capacity of fibroblasts. It is conceivable that the degree and/or type of chromosome-specific aneuploidy might have some gene dosage effects in the control of cellular proliferation and selection during aging. We also show that a combination of both interphase and metaphase aneuploidy analyses provides more comprehensive and insightful information on intraindividual cellular dynamics and chromosomal aneuploidy as a function of age. Occasionally, very small proportions of cells in two individuals showed age-related structural chromosome aberrations, such as an acentric fragment derived from an X chromosome and an achromatic gap in chromosome 7. Thus, a comparative analysis of both intra- and interindividual longitudinal studies is very useful in detecting the pattern(s) of chromosome-specific alterations with increasing age.
This paper presents the results of a survey conducted by the Royal College of Nursing (RCN) Gynaecology Nursing Forum. In late 1994/early 1995, a questionnaire was used to collect data from qualified nurses providing gynaecology hospital services throughout the UK. The questionnaire gathered information about the extent and impact of service reconfigurations following the 1989 NHS reforms (DoH 1989). The article describes these and recommends how specialist nurses can capitalise on the changes in the best interests of their patients.
In meetings arranged by the minister of Public Health, Welfare and Sports between general practitioners and specialists concerning chronic fatigue syndrome (CFS), suggestions for the diagnosis, treatment and assistance and support of patients with protracted physically unexplained fatigue symptoms, were established in the light of current scientific insight. The term 'CFS' is applicable in cases of fatigue complaints, of at least 6 months' standing, reported by the patient himself and evaluated medically, for which no physical explanation has been found and which cause considerable disabilities in professional social and/or personal functioning. The management depends on the duration of the illness. A distinction is made between an acute phase (up to one month after the first consultation; the policy is mostly expectative), a subacute phase (until 6 months after the onset of the complaints and disabilities; the management is aimed at making the patient accept the condition and persuading him or her to make an effort to promote health) and a chronic phase (from 6 months after the onset of the complaints and disabilities; the management is aimed at health-promoting behaviour and cognitions). Further (laboratory) examinations are useful only if the symptoms have not disappeared after one month (this is the case in approximately 20% of the patients); such examinations may be useful in older patients earlier. It is important that the CFS patient learns to realize that it is useless to continue to spend energy on searching for causes and possible therapies, but that he should try to promote his own health, for instance by means of a quantified programme of activities linked to a time schedule (instead of to a level of fatigue).
The generation of superoxide by the NADPH oxidase of neutrophils is accompanied by the efflux of H+ ions through a H+ channel. gp91-phox, a protein component of the oxidase, has been shown previously to function as a H+ channel [Henderson, Banting and Chappell (1995) J. Biol. Chem. 270, 5909-5916]. We have constructed a CHO cell line (CHO-N) that expresses an N-terminal fragment of gp91-phox containing the predicted multiple transmembrane domains of the protein. These cells exhibit H+ fluxes in response to an imposed proton motive force and in the presence of arachidonate (to open the channel). The H+ fluxes were indistinguishable from those observed in cells expressing full-length gp91-phox. Therefore the N-terminal 230 amino acids of gp91-phox contain all that is required to function as the NADPH oxidase-associated H+ channel.
Explore the source record for details and available documents.
STUDY DESIGN: This study evaluated the different forms of treatment of camptomelic dysplasia, a rare form of short-limbed dwarfism. OBJECTIVES: To determine the most efficacious form of management of spinal deformities in camptomelic dysplasia. SUMMARY OF BACKGROUND DATA: The literature on treatment of spinal deformities in camptomelic dysplasia is sparse. One report advocates aggressive surgical treatment to prevent curve progression and prevent already compromised respiratory function. METHODS: Eight patients with camptomelic dysplasia and progressive spinal deformity underwent a retrospective chart and radiographic review by an independent observer. Follow-up averaged 3 years and 9 months. RESULTS: Five of eight patients initially were treated with bracing and six of eight patients eventually required surgery. Average initial kyphosis was 114 degrees and scoliosis 61 degrees, compared with 99 degrees kyphosis and 52 degrees scoliosis at follow-up. Complications included pseudarthrosis (50%) and neurologic problems (33%). CONCLUSIONS: The authors advocate anterior/posterior uninstrumented fusion and halo cast immobilization postoperatively to prevent curve progression and avoid the potentially fatal sequelae associated with this disorder.