Therapeutic antibody fragments with prolonged in vivo half-lives

Antibody fragments can be isolated rapidly using techniques such as phage display and can be expressed to high levels in microbial systems. However, to date such antibody fragments have been of limited use for many therapeutic applications because they are rapidly cleared from the body. We present a strategy for the site-specific chemical modification of antibody fragments with polyethylene glycol, which results in the production of antibody fragments with long in vivo half-lives and full retention of antigen-binding properties. This technology should allow more rapid and economical production of therapeutic antibodies for chronic disease therapy.

Dry eye and dry mouth in the elderly: a population-based assessment

BACKGROUND

Symptoms of dry eye and dry mouth are common in the elderly and are often debilitating. Previous research on small populations has been inconsistent regarding the contribution to sicca symptoms of autoimmune markers, medication use, and other factors. The objective of this study was to determine the population prevalence of symptoms of dry eye and dry mouth and to evaluate possible risk factors.

METHODS

This is a population-based study of 2481 individuals, aged 65 to 84 years, residing in Salisbury, Md, and identified by the Health Care Financing Medicare database. The main outcome measures included information on sicca symptoms, medical history, medication use, and joint examination results collected in a standardized manner. Autoimmune status was assessed in 1200 individuals by measuring antinuclear antibody, rheumatoid factor, and autoantibodies to the soluble nuclear antigens Ro/SS-A and La/SS-B by double immunodiffusion.

RESULTS

Approximately 27% of the population reported dry eye or dry mouth symptoms to be present often or all the time and 4.4% reported both. The prevalence of dry mouth (but not dry eye) symptoms increased with age, female sex, and white race. No association of sicca symptoms was found with rheumatoid arthritis, smoking, alcohol consumption, reproductive hormonal status, or the presence of autoantibodies. A strong, dose-response relationship was observed between sicca symptoms and the use of certain medication classes. The proportion of the population prevalence of sicca symptoms attributable to the use of drying medications was estimated at 62% for dry eye and dry mouth and 38% for dry eye or dry mouth symptoms.

CONCLUSIONS

Sicca symptoms are common in the elderly, and medication side effects appear to be a major underlying factor. Our results do not indicate an association between autoimmune status and sicca symptoms and do not support immunologic testing in persons with sicca symptoms in the absence of other important systemic features.

Posterior C1-C2 transarticular screw fixation in the treatment of displaced type II odontoid fractures in the geriatric population--review of seven cases

BACKGROUND

Seven geriatric patients presented with displaced Type II odontoid fractures. All patients underwent a posterior C1-C2 transarticular fixation between November 1994 and December 1996. Ages ranged between 63 and 88 years.

METHODS

Fractures were treated with placement of bilateral transarticular screws, allowing immediate fixation, except in one patient, for whom only a unilateral screw was used. An autograft interspinous strut was also placed, allowing three-point fixation. Mean follow-up was 10.6 months.

RESULTS

Six patients received rigid fixation and developed a stable union. One patient died before any follow-up could be obtained. Two other patients died within 1 year of unrelated causes. The remaining four patients remain active and independent. One intraoperative vertebral artery injury was identified. No clinical sequalae were noted.

CONCLUSION

Posterior transarticular screw fixation is a reasonable option in treating these controversial fractures. Seven geriatric patients tolerated this surgery well, and were mobilized early, avoiding complications related to external immobilization.

Prolonged hypertension: A case report of a potential interaction between electroconvulsive therapy and venlafaxine

Electroconvulsive therapy is often given in addition to antidepressant drugs when there has been an inadequate response to the latter. In the case of tricyclic antidepressants and monoamine oxidase inhibitors, this is not regarded as a hazardous combination. Caution is however advised with selective serotonin re-uptake inhibitors, since there may be a prolongation of seizures. Cardiovascular complications resulting from the combination of ECT and antidepressant medication have not been previously reported. We report on a case of prolonged hypertension following ECT in a patient taking the serotonin and noradrenaline re-uptake inhibitor, venlafaxine. Possible mechanisms for this potentially very serious interaction are discussed.

Who participates in population based studies of visual impairment? The Salisbury Eye Evaluation project experience

PURPOSE

To describe characteristics of respondents and nonrespondents to a home questionnaire and comprehensive clinical examination in a population of elderly Americans.

METHODS

The SEE project is a population-based study of age-related eye diseases, visual impairment, and functional status of individuals aged 65 to 84. Potential participants were identified using the Health Care Financing Administration Medicare data base for Salisbury, MD: After sending out an introductory letter, a trained interviewer visited potential participants in their homes, obtained their consent to participate, administered a short screening interview that included questions about their general health and vision, and administered an extensive questionnaire on their diet, medical history, and difficulty performing activities related to vision. The interviewer then scheduled an appointment for the participants to visit a central site for an exam. Potential participants could fall into one of two refusal groups; refusal to take part in the study before the home questionnaire or prior to the clinic visit.

RESULTS

The overall response rate for the clinic visit was 65%. Compared to individuals with complete exams, the two groups of refusals were older, less likely to have any college education, more likely to report poor health status, and more likely to need help with Independent Activities of Daily Living (IADL's). Participants with complete home questionnaires that failed to come to the clinic were more likely to have Mini-Mental scores below 25. There were not significant differences by race, gender, or self reported vision status among the three groups.

CONCLUSIONS

Population-based studies requiring an in-clinic examination may selectively under-sample those with health and mental difficulties. These differential responses may introduce bias in the study results and need to be addressed when assessing the burden, type and severity of disease in the community. However, self-report of visual status was similar among refusals and participants in this study on vision.

Familial adenomatous polyposis associated with multiple adrenal adenomas in a patient with a rare 3' APC mutation

Familial adenomatous polyposis (FAP) is characterised by hundreds of colorectal adenomas. Endocrine neoplasms have occasionally been reported, as have gastric polyps, which are usually hamartomatous in the fundus of the stomach and adenomatous in the antrum. A 57 year old man with colorectal, gastric, and periampullary adenomatous polyposis, in association with three bilateral adrenocortical adenomas, is presented. Mutation screening showed a 5960delA germline mutation in the adenomatous polyposis coli (APC) gene predicted to lead to a premature stop codon. This mutation was found in three of the four children of the patient. Western blot analysis of a lymphoblastoid cell line derived from the patient failed to detect any truncated APC polypeptide. This rare 3' mutation is responsible for an unusually complex and late onset phenotype of FAP.

Multiplex SSCP and heteroduplex analysis with Southern hybridization for large-scale mutation detection

We have developed a modification of the single-strand conformational analysis and heteroduplex analysis methods of mutation detection, with the intention of applying them to genetic diseases involving large genes or multiple genes producing a similar phenotype. The technique involves electrophoresing up to 10 or more DNA fragments on a polyacrylamide gel, followed by bidirectional Southern blotting and individual examination by hybridization. This can reduce the time involved in mutation detection by more than 50%. We confirmed the validity of our approach by detecting 90% of mutations in a blind study of previously characterized mutations in the adenomatous polyposis coli (APC) gene that underlies familial adenomatous polyposis.

Effect of catheter tip length and position on lesion volume in temperature controlled RF ablation in canine tricuspid valve annulus

BACKGROUND

Radiofrequency (RF) energy has been delivered to the tricuspid valve annulus (TVA) in humans with both 4 mm and 8 mm long catheter tip electrodes to treat atrial flutter. However, lesion volume with temperature controlled RF delivery systems has not been previously characterized.

METHODS

In 10 anesthetized canines, a single pulse of temperature controlled RF energy at a 70 degrees C set point, 30 second duration was delivered with either a 7 Fr/4 mm tip or a 7 Fr/8 mm tip electrode in a position both anterolateral and posteroseptal to the tricuspid valve annulus (TVA). Surface echocardiogram was obtained prior and after ablation. The animals were sacrificed after ablation and the lesions underwent gross and histological examination.

RESULTS

Lesion size, tip temperature and power were related to tip electrode surface area (SA). Eight mm tips (SA = 59 mm2) tended to create significantly larger lesions than 4 mm tips (SA = 29 mm2). Median lesion volume was 22 vs. 1.5 mm3, respectively. Eight mm tips were also associated with higher power requirements and lower temperatures than 4 mm tips. Posteroseptal TVA lesions tended to be larger than anterolateral lesions. No significant complications were noted.

CONCLUSIONS

Using temperature controlled RF ablation, large lesions may be safely created on the canine TVA using 7 Fr catheters with 8 mm long tips.

Temperature controlled RF ablation in canine ventricle and coronary sinus using 7 Fr or 5 Fr ablation electrodes

The safety and lesion volume of temperature controlled radiofrequency ablation (TCRFA) in the right ventricle (RV), left ventricle (LV), and coronary sinus (CS) comparing long 5 Fr to standard tip electrodes have not been previously reported. In 10 canines, TCRFA was delivered at a 70 degrees C set point for 30 seconds. Lateral and septal RV lesions were made with either a 5 Fr/5 mm or 7 Fr/4 mm tip. Lateral and septal LV lesions were made with either a 5 Fr/7 mm or 7 Fr/4 mm tip. Proximal and distal CS lesions were made with either a 7 Fr/4 mm, 5 Fr/5 mm or 5 Fr/7 mm tip. Gross and histologic examination of the lesions was completed. Lesion size, tip temperature and power required are related to electrode surface area (SA) when ablating in the RV, LV or CS. 5 Fr/7 mm tips (SA = 36 mm2) tended to create larger lesions than 7 Fr/4 mm tips (SA = 29 mm2) in the LV. 7 Fr4 mm tips tended to create larger lesions than 5 Fr/5 mm tips (SA = 26 mm2) in the RV. 7 Fr/4 LV lesions exceeded 7 Fr/4 mm RV lesions due to thicker LV walls. In the CS, 5 Fr/7 mm tips tended to create the largest lesions. In the RV, LV and CS, tips with larger SA tended to have lower temperatures and require higher power. No high temperature or high impedance shut-downs were observed. In conclusion, varying 5 Fr tip length can safely produce larger or smaller lesions compared to those created with 7 Fr/4 mm tips.

Entrance qualifications and student performance in a hybrid problem based and traditional medical programme

A hybrid problem based learning (PBL) and traditional medical programme was started at the Trinidad campus of the University of the West Indies in 1989. Analyses were carried out to determine the extent to which the entrance qualifications of the students were related to their performances at the examinations in the Phase I (preclinical and paraclinical) and Phase II (clinical) programmes. Students who were admitted on the basis of their results in the secondary school General Certificate of Examination (GCE), 'A' level scored higher at the Phase I, but not at the Phase II, level than those who already had university education. Among the 'A' level students, there was positive correlation between the total 'A' level scores and the examination marks in the medical programme, particularly at the Phase I level. Furthermore, multiple regression analyses indicated that the grades in 'A' level Chemistry and, to a lesser extent in Biology, had the most influence on performances at the Phase I examinations, with much less influence on performances at the Phase II examinations. These results suggest that good grades at 'A' level examinations are significant factors, but not the only important ones, that favour high achievement in the initial stages of this type of PBL/traditional medical programme.

Severe disease in children with trachoma is associated with persistent Chlamydia trachomatis infection

The immediate study objective was to determine if variable disease severity in children with trachoma could be attributable in part to host variation in the ability to clear Chlamydia trachomatis infection. Identification of sibling cohorts with these variant phenotypes would be useful for immunogenetic studies. A weekly survey for 3 months in a trachoma-hyperendemic village using detection of chlamydial DNA and grading of disease severity indicated that 62% (33/53) of children had at least one infection episode. Of those, 64% (21/33) who were persistently infected had both significantly higher mean chlamydial DNA loads and more severe trachoma than did sporadically infected children. Of importance, duration of infection differed between siblings in 60% (6/10) of families. The results suggest that chlamydial load and duration of infection determine the chronic nature of severe disease in trachoma and that host variable efficiency for chlamydial clearance between siblings is in part determined by host variation.

Prevalence of dry eye among the elderly

PURPOSE

To study the demographics and estimate the prevalence of dry eye among elderly Americans.

METHODS

A population-based prevalence study was performed in 2,520 residents of Salisbury, Maryland, aged 65 years and older as of September 1993. The population was derived from the Health Care Financing Administration Medicare database. After completing a standardized questionnaire pertaining to dry eye symptoms, 2,420 subjects underwent Schirmer and rose bengal tests and anatomic assessment of the meibomian glands.

RESULTS

In this population, 14.6% (363/2,482) were symptomatic, defined as reporting one or more dry eye symptoms often or all the time; 2.2% (53/2,448) were symptomatic and had a low Schirmer test result (< or = 5 mm), and 2% (48/2,432) were symptomatic and had a high rose bengal test score (> or = 5). Furthermore, 3.5% (84/2,425) were symptomatic and had either a low Schirmer score or a high rose bengal score, and 0.7% (17/2,420) were symptomatic and had both a low Schirmer score and a high rose bengal score. No association of symptoms or signs was seen with age, sex, or race. Although anatomic features of meibomianitis were associated with the presence of symptoms (P = .01), 76% (67/88) of the individuals with these anatomic features were asymptomatic; 10.5% (260/2,480) reported that they currently use artificial tears or lubricants.

CONCLUSIONS

Symptoms and signs of dry eye are common among the elderly but were not associated with age, race, or sex in this population-based sample of elderly Americans. Extrapolating to the United States population aged 65 to 84 years, the study yields an estimate of 4.3 million who experience symptoms of ocular irritation often or all the time.

Incidence estimates of late stages of trachoma among women in a hyperendemic area of central Tanzania

The purpose of this study is to estimate 5-year incidences of conjunctival scarring and trichiasis, and 10-year incidence of corneal opacities due to trachoma, using prevalence data from a population sample of 6038 women living in a trachoma-hyperendemic area of central Tanzania. Previous surveys have documented the age-specific prevalence of scarring, trichiasis, and corneal opacities in women in hyperendemic areas. Using the age-stratified prevalences of these different clinical signs, corresponding incidence rates were estimated. Transition rates from one sign to the next were also obtained by restricting the risk group to only women with a specific trachoma sign. Thus, the 5-year incidence of trichiasis among women with conjunctival scarring, and the 10-year incidence of corneal opacities among women with trichiasis were estimated. Incidences of all the signs markedly increased with age. For scarring, 5-year incidence rates increased from 3.1% in the 15-19 age category to 14.3% for women between 55 and 59 years. The 5-year incidence of trichiasis ranged from 0.3% in the 15-19 age category to 7.5% in the age group 55-59. Corneal opacities due to trachoma were highest in the age group 45-54; the 10-year incidence increased to 2.8%. The 5-year incidence of trichiasis among only women with scars increased from 3.2% in the 15-19 age group to 15.1% in women in the 55-59 age group. Once trichiasis is present, almost one-third of the women below 35 and more than 40% of the women older than 45 will develop corneal opacities in a 10-year interval. These estimates are important in understanding the dynamics of progression of trachoma from conjunctival scarring to the potentially blinding signs of trichiasis and corneal opacities. They provide important information for planning adequate services in areas where trachoma is endemic and surgery for trichiasis is a key factor to avoid blindness from trachoma. They also provide clues to the pathogenesis that may be useful in the development of new methods of control.

Eye care utilisation patterns in a rural county in Ireland: implications for service delivery

AIMS/BACKGROUND

This investigation determined eye care utilisation patterns in a rural county in Ireland. Population based estimates of visual impairment and glaucoma were available, so the two studies will optimise planning for eye care services for the county.

METHODS

Roscommon has a population of 55,000 served by one ophthalmologist and two optometrists. Data were collected on all outpatient visits for all providers for a 3 month period. Information was abstracted on demographics, presenting and final diagnoses. Expected number of visits for glaucoma were calculated using the population structure and rates of glaucoma, and assuming one visit per year per glaucoma patient.

RESULTS

1398 patients had a total of 1442 visits in 3 months. A third of the visits were to optometrists, and all but 21 visits were for normal eye examinations or glasses. The majority of children aged less than 16 years, and people older than 60 years were seen by the ophthalmologist. Among children, 81% of all visits were to the ophthalmologist and 92% were classified as a normal examination. Only an estimated 188 visits per year for glaucoma were observed, compared with 1100 expected.

CONCLUSION

In this rural county, many of the visits to the ophthalmologist were for normal eye examination, particularly among children. Screening algorithms which would free the ophthalmologist to see more complicated problems could be considered. There is an underutilisation of services by glaucoma patients. Reasons for this are described.

Relation between signs and symptoms of dry eye in the elderly. A population-based perspective

PURPOSE

To examine the distribution and association of dry eye symptoms, Schirmer test results, and rose bengal scores in a population-based sample of elderly Americans.

DESIGN

Population-based prevalence survey.

PARTICIPANTS

Involved were 2240 noninstitutionalized residents of Salisbury, Maryland, aged 65 years and older as of September 1993, and identified by the Health Care Financing Administration Medicare database.

MAIN OUTCOME MEASURES

A standardized dry eye symptom questionnaire, rose bengal scoring of ocular surface staining, and Schirmer tests.

RESULTS

Fourteen percent of participants reported one or more symptoms to be present often or all the time. The mean Schirmer score in the lower testing eye was 12.4 and 42% had a rose bengal score of 1 or greater. No significant differences by age, gender, or race were seen for symptoms, Schirmer, or rose bengal testing. No association was seen between lower Schirmer scores and presence of more frequent symptoms. Higher rose bengal scores were weakly associated with symptoms. The Schirmer and rose bengal test results, both individually and in combination, were insensitive in identifying individuals who had symptoms.

CONCLUSIONS

Although symptoms of ocular irritation are common among the elderly, these population-based data indicate that there is minimal overlap between individuals identified by questionnaire, Schirmer tests, and rose bengal scoring.

Absence of a relationship between malnutrition and trachoma in preschool children

PURPOSE

To determine if there is an association between malnutrition and clinical trachoma among children in a trachoma endemic region of Tanzania.

METHODS

189 children age one to five were examined by a trained eye nurse for the presence of active trachoma, using the WHO simplified grading scheme. One examiner also measured the arm circumference of the mid-aspect of the upper left arm on the same children. Trachoma was defined as the presence of follicular trachoma (TF) and/or severe trachoma (TI). Malnutrition was defined two ways: a mid-arm circumference of less than 12.5 cm, and a value one standard deviation below the age-specific mean.

RESULTS

Overall, 57% of children had trachoma, and 9% had severe trachoma. The percentage of children with arm circumference below 12.5 cm varied with age from 96% in the one-year-olds to 35% in the six-year-olds. Using either method of classifying malnutrition, there was no association with trachoma, nor with severe trachoma.

CONCLUSION

Trachoma and malnutrition are both common in this sample of children, although no relationship between the two was observed. Further work on the nutritional status in those with subclinical infection may be warranted.

Low-level visual processing of biological motion

Biological motion displays depict a moving human figure by means of just a few isolated points of light attached to the major joints of the body. Naive observers readily interpret the moving pattern of dots as representing a human figure, despite the complete absence of form cues. This paper reports a series of experiments which investigated the visual processes underlying the phenomenon. Results suggest that (i) the effect relies upon responses in low-level motion-detecting processes, which operate over short temporal and spatial intervals and respond to local modulations in image intensity; and (ii) the effect does not involve hierarchical visual analysis of motion components, nor does it require the presence of dots which move in rigid relation to each other. Instead, movements of the extremities are crucial. Data are inconsistent with current theoretical treatments.

Blindness and visual impairment in western Bulgaria

The Sofia Eye Survey was a population-based blindness and visual impairment survey of 6,275 randomly selected men and women from the Sofia district and Sofia city in western Bulgaria. A complete house-to-house census on all adults over age 40 years was performed, and visual acuity performed on 98%. We referred 171 subjects for a complete dilated ophthalmologic examination because the pinhole vision in the better eye was 6/18 or worse. Trained ophthalmologists refracted all referred subjects and then examined them with a slit lamp and ophthalmoscopy to determine the cause of visual loss. The rate of blindness (defined as vision in the better eye worse than 3/60) in this population was 0.49% and the rate of visual impairment (6/18 to 3/60 in the better eye) was 0.83%. The leading cause of both blindness and visual impairment was cataract. These data from the first community-based survey of blindness in Eastern Europe suggest that the rates of blindness and visual impairment are similar to those reported from other developed countries.

Evidence for a predominant proinflammatory conjunctival cytokine response in individuals with trachoma

Immune responses to Chlamydia trachomatis infection in trachoma do not protect against reinfection or the development of scarring and blindness. In addition, the immunoregulatory contribution of cytokines to the development of conjunctival histopathology or protection is undefined. In this study, conjunctival cytokine mRNA transcripts were compared among subgroups of chlamydia infection status and ocular disease presentations of 50 individuals from an area where trachoma is endemic. There was a significant association of elevated interleukin (IL)-1beta, transforming growth factor beta1, and tumor necrosis factor alpha transcripts with infection, follicular inflammation, and scarring. Both gamma interferon (IFN-gamma) and IL-2 transcripts were significantly associated with infection; slightly elevated IL-2 levels were found in inflammatory disease. High IFN-gamma transcript levels were present with follicles and inflammatory disease and to a lesser extent with inflammatory scarring. The role of IFN-gamma in protection from infection or disease was not apparent from this study, since transcripts were frequently present in both chlamydial infection and disease. IL-12 (p40) transcripts were elevated in adults and children in association with follicular inflammation but not with scarring. IL-4, IL-5, and IL-10 transcripts were not detected in any samples. In conclusion, C. trachomatis infection stimulates local cytokines which favor a strong cell-mediated and proinflammatory response in both the early and later manifestations of trachoma. In addition, cytokine transcript levels that were associated with disease but no infection were characteristically lower overall than when chlamydia was present.

Northrhine Westphalian data on the HumTH01 locus

A population study was carried out on 302 ethnic Germans from Düsseldorf and 273 ethnic Germans living in Northrhine Westphalia using the short tandem repeat (STR) system HumTH01 (TC11). Seven different alleles were detected. No deviations from the Hardy-Weinberg equilibrium could be observed. The results were compared with other population studies. The pooled sample from Germany can be used as database for forensic purposes.

Cigarette smoking and risk for progression of nuclear opacities

OBJECTIVE

To examine the relationships between smoking and the 5-year incidence of new nuclear opacities and between smoking and the progression of nuclear opacities in a prospective study of a cohort of Chesapeake Bay watermen.

METHODS

A total of 442 men (age, > or = 30 years in 1985) with paired, gradable lens photographs in at least one eye in both 1985 and 1990 were studied. Photographs were graded by two readers who used the grading scheme of the Wilmer Institute, Baltimore, Md, with severity ranging in decimal units between 0.0 and 4.0. Data on the smoking history of the subjects were collected by personal interviews that were conducted in 1985 and updated in 1990.

RESULTS

The incidence and progression of opacities increased with age. A nonsignificant association was observed between smoking (for both current and ex-smokers) and the incidence of a nuclear opacity. The risk of progression of nuclear opacities of less than grade 3 at baseline to grade 3 or worse was 2.4-fold higher among current smokers in 1985, compared with that among ex-smokers and nonsmokers (95% confidence limits: 1.0, 6.0) after adjustment for age, baseline opacity status, and alcohol use. An 18% increased risk of progression was significantly associated with each pack-year that a subject smoked between 1985 and 1990.

CONCLUSION

These data confirm previous findings that smoking is associated with a nuclear opacity, particularly with progression to severe opacities.

The genetic background of familial adenomatous polyposis. Linkage analysis, the APC gene identification and mutation screening

Familial adenomatous polyposis (FAP) is an autosomal, dominantly inherited disease that predisposes to colorectal cancer and is characterized by the presence of hundreds to thousands of adenomas covering the colon and rectum. Mapping of the FAP locus to 5q21-q22 by linkage studies in families ultimately allowed the identification of the APC (Adenomatous Polyposis Coli) gene itself. The APC gene comprises 15 exons with a 9 kilobase RNA transcript and a 312 kilodalton final protein product. This discovery transformed the diagnosis of FAP and offered direct identification of defective gene carriers by mutation screening. Currently used techniques have been successful in detecting mutations in 15 to 67 percent of patients. To date, at least 136 different mutations have been described in 301 unrelated FAP patients, most of which (98%) are translation terminating mutations leading to a truncated final protein product. Promising applications or development of novel procedures, like the protein truncation test (PTT), are under way for the remaining FAP patients. With the exception of the description of a critical boundary in exon 9 for the presence or absence of CHRPE, there are no clear genotype-phenotype relationships, but mutations located in the 5' half of exon 15 seem to lead to a more severe phenotype. Very little is know about the APC protein product function. The APC protein could be involved in cell-to-cell signalling and/or cell adhesion functions. The APC gene is a tumour suppressor gene involved in early stages of sporadic colorectal carcinogenesis. Further understanding of the APC gene function may define a rational approach for early detection, prevention strategies, assessment of prognosis and treatment of colorectal cancer. In this regard, animal models of FAP, like the MIN (Multiple Intestinal Neoplasia) mouse or the APC 1638 mouse, are promising and powerful tools.

Ocular and dermatologic health effects of ultraviolet radiation exposure from the ozone hole in southern Chile

OBJECTIVES

This study sought to investigate numerous reports emanating from Punta Arenas, Chile (population 110,000, latitude 53 degrees S), that associated acute ocular and dermatologic disease in humans and animals with excess ultraviolet-B (UV-B) exposure in the setting of the thinning of the ozone column.

METHODS

Ophthalmologic and dermatologic records in Punta Arenas were systematically reviewed to enumerate sentinel diagnoses potentially associated with UV-B exposure, ocular examinations on representative animal populations were performed, and the ambient UV-B exposure in the region during the time of maximal thinning was estimated.

RESULTS

No increase in patient visits or conditions attributable to UV-B exposure was seen for periods of known ozone depletion compared with control periods. Although ambient UV-B exposure was 1.6 to 2.3 times the habitual exposure on individual days, this excess exposure conferred only a 1% increase in annual exposure on the region.

CONCLUSION

This study does not support existing lay reports of ocular and dermatologic disease in humans and animals that had been associated with the ozone hole over southern Chile.

The clinical [corrected] background of familial adenomatous polyposis. History, epidemiology, diagnosis and treatment

Familial adenomatous polyposis (FAP) is a dominantly inherited genetic disorder predisposing to colon cancer through the early development of multiple adenomatous polyps in the large bowel. FAP is not restricted to the colon and rectum, but is a more complex disease which can potentially affect almost any organ not only with benign tumours but also with life threatening carcinomas. Desmoid tumours and gastroduodenal polyps and cancer are the two more worrying extracolonic manifestations of FAP. Recent advances in FAP knowledge, such as the report of congenital hypertrophy of the retinal pigment epithelium (CHRPE) or the APC gene identification, are very useful for screening and long-term follow-up of the patients through regional or national registries. Nutritional and pharmacological intervention trials are under way to assess potential new medical treatments of FAP. Surgery is still the only effective treatment for colorectal cancer prevention in FAP. The choice of a surgical procedure is controversial, but the introduction of total proctocolectomy with ileal pouch-anal anastomosis can be considered as a major advance in surgical treatment of FAP during the last decade.

Impact of face-washing on trachoma in Kongwa, Tanzania

Observational studies have suggested that the prevalence of trachoma is lower in children with clean faces than in those with ocular or nasal discharge or flies on the face. We carried out a community-based randomised trial in three pairs of villages to assess the impact on trachoma of a face-washing intervention programme following a mass topical antibiotic treatment campaign. Six villages in Kongwa, Tanzania, were randomly assigned mass treatment plus the face-washing programme or treatment only. 1417 children aged 1-7 years in these villages were randomly selected and followed up for trachoma status and observations of facial cleanliness at baseline and 2, 6, and 12 months. At 12 months, children in the intervention villages were 60% more likely to have had clean faces at two or more follow-up visits than children in the control villages. The odds of having severe trachoma in the intervention villages were 0.62 (95% Cl 0.40-0.97) compared with control villages. A clean face at two or more follow-up visits was protective for any trachoma (odds ratio 0.58 [0.47-0.72]) and severe trachoma (0.35 [0.21-0.59]). This community-based participatory approach to face-washing intervention had variable penetration rates in the villages and was labour intensive. However, we found that, combined with topical treatment, community-based strategies for improving hygiene in children in trachoma-endemic villages can reduce the prevalence of trachoma.

Shingles, allergies, family medical history, oral contraceptives, and other potential risk factors for systemic lupus erythematosus

The authors undertook a case-control study to explore the many factors that have been postulated to be related to the etiology of systemic lupus erythematosus. A total of 195 cases of systemic lupus diagnosed in the Philadelphia, Pennsylvania, metropolitan area between 1985 and 1987 were compared with 143 controls, friends of the cases matched to them according to age (+/- 5 years) and sex. Through personal interviews and chart reviews, data were collected on demographic factors, personal and familial medical history, reproductive history, medication history, and environmental exposures. Associations were found between systemic lupus erythematosus and having a family history of autoimmune disease (age-, sex-, and race-adjusted odds ratio (OR) = 2.3, 95% confidence interval (CI) 1.2-4.6), a history of shingles (adjusted OR = 6.4, 95% CI 1.4-28.0), a history of hives (adjusted OR = 1.8, 95% CI 1.1-3.0), and a history of medication allergies (adjusted OR = 2.6, 95% CI 1.5-4.5). No association was present between systemic lupus erythematosus and either any use or recent use of oral contraceptives (e.g., OR = 0.6 (95% CI 0.2-1.4) for use in the 3 years prior to diagnosis), family history of multiple other diseases, or a history of numerous other infections or various other types of allergies. Thus, these data indicate that systemic lupus erythematosus is associated with a family history of autoimmune diseases, a history of shingles, and a history of allergies. In contrast, if the development of systemic lupus is affected by use of oral contraceptives, this effect must be extremely modest. These findings may help clarify the possible pathogenesis of systemic lupus erythematosus, and they provide clues as to when the presence of systemic lupus should be suspected.

Sacroiliac joint: pain referral maps upon applying a new injection/arthrography technique. Part I: Asymptomatic volunteers

STUDY DESIGN

Pain pattern mapping of the sacroiliac joint in asymptomatic volunteers was investigated. Prospective evaluation of 10 volunteers who received sacroiliac joint injections was performed. The injections consisted of contrast material followed by Xylocaine.

OBJECTIVES

To determine the pain referral pattern of the sacroiliac joint in asymptomatic individuals.

SUMMARY OF BACKGROUND DATA

All 10 individuals experienced discomfort upon initial injection, with the most significant sensation felt directly around the injection site. Subsequent sensory examination revealed an area of hypesthesia running caudally from the posterior superior iliac spine.

METHODS

Volunteers were asked to describe the nature and location of the sensation upon sacroiliac injection. Sensory examination immediately followed the injection to determine referral patterns.

RESULTS

Sensory examination immediately after sacroiliac injection revealed an area of buttock hypesthesia extending approximately 10 cm caudally and 3 cm laterally from the posterior superior iliac spine. This area of hypesthesia corresponded to the area of maximal pain noted upon injection.

CONCLUSION

A pain referral map was successfully generated using provocative injections into the right sacroiliac joint in asymptomatic volunteers.

Junior Doctors' Hours: What Do They Really Think?

Junior doctors' hours are one of the most controversial topics under debate in the health service today. We undertook a detailed postal questionnaire of hospital doctors in training within a major teaching unit in order to assess the awareness and perceived implications of the incipient changes and to elucidate how it was felt these changes would affect both the doctors and patients.

The questionnaire focused specifically on the effect of the changes on quality and continuity of patient care, junior training and socio-economic factors relating to the medical staff.

The questionnaire was entirely anonymous and carried only the first author name but provision was made to determine current grade, speciality, age, sex and career plans of the respondents. Importantly, space was included at the end for pertinent comments.

All junior staff in training in all specialities in the Cardiff area were circulated. Three hundred and twenty-six questionnaires were sent out and 202 were returned of which 192 were properly completed (59%).

Almost everyone was au fait with the proposed changes. There was a surprisingly high level of support for changes among non-surgical trainees, and half felt that quality of care would improve, though the more senior the trainee, the less enthusiastic they were in all aspects. Many felt that far too little consultation with junior staff had taken place and there was generalized criticism of general practitioner trainees by their specializing counterparts, partly because of a perceived lack of commitment and partly because of blame of this group for the inception of the changes.

Most importantly, there was solid opposition among surgeons in training because of a perceived reduction in patient care, compromise in quality of training and a belief that the system is unworkable [only 9% of registrars and senior registrars and 25% of senior house officers (SHOs) and housemen planning a surgical career were in favour of change].

It is clear that different specialities need to be assessed separately. For example, the requirements for covering a partial shift system for special baby care, or anaesthetics are very different from the on call requirements of dermatology or urology. It is inappropriate to put every speciality under the same umbrella and this should be rethought before the introduction of the 72 h week results in unnecessary but predictable chaos.

Junior doctors' hours: what do they really think?

Junior doctors' hours are one of the most controversial topics under debate in the health service today. We undertook a detailed postal questionnaire of hospital doctors in training within a major teaching unit in order to assess the awareness and perceived implications of the incipient changes and to elucidate how it was felt these changes would affect both the doctors and patients. The questionnaire focused specifically on the effect of the changes on quality and continuity of patient care, junior training and socio-economic factors relating to the medical staff. The questionnaire was entirely anonymous and carried only the first author name but provision was made to determine current grade, specialty, age, sex and career plans of the respondents. Importantly, space was included at the end for pertinent comments. All junior staff in training in all specialties in the Cardiff area were circulated. Three hundred and twenty-six questionnaires were sent out and 202 were returned of which 192 were properly completed (59%). Almost everyone was au fait with the proposed changes. There was a surprisingly high level of support for changes among non-surgical trainees, and half felt that quality of care would improve, though the more senior the trainee, the less enthusiastic they were in all aspects. Many felt that far too little consultation with junior staff had taken place and there was generalized criticism of general practitioner trainees by their specializing counterparts, partly because of a perceived lack of commitment and partly because of blame of this group for the inception of the changes.(ABSTRACT TRUNCATED AT 250 WORDS)

Molecular similarity, quantitative chirality, and QSAR for chiral drugs

The current policy of drug regulatory authorities demanding that pharmaceutical companies justify their reasons for preferring drugs containing a mixture of enantiomers over one stereoisomer increases the importance of quantitative structure-activity relations (QSARs) for chiral drugs. The QSAR proposed by Pfeiffer for chiral drug enantiomer potencies was brought into question by the existence of sets obeying an anti-Pfeiffer rule. Using computer-aided molecular design methods and treating chirality not as an existing/nonexisting property but as a continuous one improve the QSAR proposed by Pfeiffer, yielding higher correlation coefficients and an independent ordinate. Calculated shape similarities reveal the details of the Pfeiffer behavior and the source of the anti-Pfeiffer behavior. Consequently revised models for the D2 and sigma receptor are suggested.

Functional status and quality of life measurement among ophthalmic patients

OBJECTIVES

Assessment of the relationship between visual function and functional status/quality of life in clinical research involving patients with eye disease by investigating whether the scores of four existing functional status/quality of life patient questionnaires are sensitive to differences in visual acuity and studying whether selected subscales of the questionnaires provide similar information concerning the relationship between functional status/quality of life and visual acuity as do the respective full-length questionnaires.

DESIGN, SETTING, PARTICIPANTS

Case patients consisted of 86 consecutive patients seen at The Wilmer Ophthalmological Institute Retinal Vascular Center, Baltimore, Md. Controls consisted of 51 individuals with normal visual acuity and no known ocular disease and were frequency-matched to the case patients by age (+/- 5 years), sex, and race. Subjects were interviewed in person using each of the following questionnaires: the Sickness Impact Profile, the vision-specific Sickness Impact Profile, the Community Disability Scale, and the General Health Questionnaire.

RESULTS

Scores of all four questionnaires and their subscales were significantly associated with visual acuity. The vision-specific Sickness Impact Profile and the Community Disability Scale were independently significant predictors of visual acuity. Regression analysis revealed that in our study, selected subscales of the respective full-length questionnaires were able to demonstrate the association between vision and functional status/quality of life.

CONCLUSIONS

Ophthalmic patients are at high risk for decreased functional status/quality of life. Subscales of existing questionnaires potentially may be substituted for the full-length questionnaires, thereby increasing the efficiency of functional status/quality of life measurement in such patients.

Cortical lenticular opacification: distribution and location in a longitudinal study

PURPOSE

To examine the distribution of cortical opacification of the lens by lens quadrant in a longitudinal study.

METHODS

In 1990, a follow-up assessment of a cohort of Chesapeake Bay watermen, initially studied in 1985, was performed. Four hundred thirty-seven subjects (834 eyes) had gradable cortical photographs for at least one eye in both 1985 and 1990. Cortical photographs were graded by both estimating total area and determining the quadrant with the greatest degree of cortical opacification.

RESULTS

The prevalence and severity of cortical opacification increased with age with a high degree of concordance (84%) between eyes. For the 47 eyes with cortical opacification > or = 1/8 at baseline, the principal locations of opacification were: inferonasal 63.8%, inferotemporal 17.0%, superonasal 6.4%, and superotemporal 12.8% (P < 0.001, compared with equal distribution by quadrant). Five-year development of new cortical opacification and five-year progression of existing cortical opacification showed even greater preferential occurrence in the inferonasal quadrant of the lens.

CONCLUSIONS

In this population, the inferonasal quadrant of the lens is the principal site of cortical opacification in both cross-sectional and longitudinal assessment. This finding is consistent with the hypothesis that sunlight exposure is a significant risk factor for cortical opacification.

Are antioxidants or supplements protective for age-related macular degeneration?

OBJECTIVES

The relationships between fasting plasma levels of retinol, ascorbic acid, alpha-tochopherol, and beta-carotene and age-related macular degeneration (AMD) were studied in a population enrolled in the Baltimore Longitudinal Study of Aging (BLSA), in which most of the data were collected 2 or more years before assessment of macular status.

DESIGN

A total of 976 participants in the study were scheduled for a biennial examination from January 1988 through January 1, 1990, which included taking lens and macular photographs. A total of 827 (85%) of the participants had fundus photographs taken, and most plasma data were available for 82% of those subjects with fundus photographs. Age-related macular degeneration was defined as neovascular changes, geographic and nongeographic atrophy, large or confluent drusen, or hyperpigmentation. A total of 226 cases of AMD were available for analysis.

RESULTS

Logistic regression analyses suggested that alpha-tocopherol was associated with a protective effect for AMD, adjusted for age, sex, and nuclear opacity. An antioxidant index, including ascorbic acid, alpha-tocopherol, and beta-carotene, was also protective for AMD. Our conclusions must be tempered with the knowledge that the population under study was basically well nourished, and few individuals had any clinically deficient status. The study cannot exclude the possibility that quite low levels of micronutrients, lower than those observed in this study, might be risk factors for AMD.

CONCLUSIONS

The data suggest a protective effect for AMD of high plasma values of alpha-tocopherol. An antioxidant index, composed of plasma ascorbic acid, alpha-tocopherol, and beta-carotene, was also protective. The use of vitamin supplements to prevent AMD is not supported by these data, which showed no protective effect of vitamin use.

Predicting surgical compliance in a cohort of women with trichiasis

Trichiasis/Entropion are the severe consequences of chronic trachoma during early life. Blindness and vision loss is preventable with timely lid surgery to correct trichiasis. In a trachoma hyperendemic region of Central Tanzania, a two year follow-up survey was conducted among 205 women with trichiasis to determine the proportion who had had surgery and the barriers to having surgery. Only 18% of the women had undergone surgery by the 2 year follow-up. Those who had surgery tended to report more eye problems at baseline and have more corneal opacities at baseline. Barriers preventing women from going to surgery were costs, problem of children left at home alone, and difficulties in identifying someone to accompany them to the health center. Over 2/3 of those who had surgery reported a significant decrease in pain, improvement of vision, and improved ability to carry out activities of daily life. Ways to improve compliance with recommendations for trichiasis surgery need to be developed.

Endotracheal suction for adult, non-head-injured, patients. A review of the literature

The procedure for endotracheal suctioning was perceived as a problem by the members of a quality circle in the intensive care unit (ICU). Endotracheal suction, when performed in the unit, appeared to be carried out according to the nurses' experience and expertise, and had no formal research backing. An extensive literature search was undertaken, and a framework for endotracheal suction was formulated based on the available evidence. Some of the aspects of endotracheal suction represented in the research evidence appear contradictory, and nurses must make a professional judgement about their suction technique based on the individual circumstances of patients. The wealth of evidence available regarding endotracheal suctioning allows nurses to make an informed decision about care.

Non-viral risk factors for nasopharyngeal carcinoma in the Philippines: results from a case-control study

In a case-control study of NPC conducted in the Philippines, 104 predominantly non-Chinese (< 10% ethnically Chinese) cases of nasopharyngeal carcinoma (NPC) and 205 hospital and community controls were recruited. Risk factor information was obtained through personal interview. The occupational history of each subject was reviewed "blind" by an industrial hygienist to determine estimates of exposure to formaldehyde, solvents, dusts, exhaust and pesticides. After control for confounding, subjects who were first exposed to formaldehyde 25 or more years prior to diagnosis/interview or wo were first exposed before the age of 25 were found, in relation to those never exposed, to be at a 4.0-fold excess risk of disease. Similarly, those first exposed to dust and/or exhaust 35 or more years prior to diagnosis/interview were at a 4.4-fold excess risk of disease and those first exposed before the age of 20 were at a 3.5-fold excess risk of disease. Salted fish consumption was not associated with risk, while consumption of processed meats protected against NPC. Smoking was positively associated with NPC, but only when cases were compared to community controls. Relative to non-smokers, subjects reporting more than 30 years of smoking were at an adjusted 7.2-fold excess risk of disease. Herbal medicine use and burning of anti-mosquito coils were both independently associated with risk of NPC, with ever-users of herbal medicines being at a 2.5-fold excess risk of disease and those reporting daily use of anti-mosquito coils being at a 5.9-fold excess risk of disease relative to never users. Exposure to solvents, pesticides, or use of betel nuts were not associated with NPC risk.

Nonocular Chlamydia infection and risk of ocular reinfection after mass treatment in a trachoma hyperendemic area

PURPOSE

The presence of nasal discharge on a child's face increases the risk of active trachoma, suggesting that Chlamydia trachomatis in nasal secretions may be a possible source of ocular reinfection. The prevalence of chlamydia in nasal secretions and the risk of reinfection after mass treatment was investigated in a hyperendemic area of Tanzania.

METHODS

In one village a total of 232 children aged 1 to 7 years were followed before and after mass treatment. Clinical trachoma, and microbiologic evidence of chlamydia, were assessed at baseline, 2 and 4 weeks into mass treatment, and 4 weeks after treatment stopped. The presence of chlamydia in ocular and nasal secretions was determined by polymerase chain reaction-enzyme immunoassay techniques.

RESULTS

Of the 232 children, 59% had clinical trachoma and 27% had nasal specimens positive for chlamydia. Children with positive ocular chlamydia specimens and/or clinical trachoma were significantly more likely to have positive nasal specimens. At the end of mass treatment, only 4% of children had positive ocular specimens. However, 1 month after treatment stopped, the incidence of new infection was 21%. The rate of new ocular infections in those who had negative ocular specimens after treatment was similar between those who had positive and those who had negative nasal specimens at baseline. Positive ocular specimens at baseline was not a predictor of risk of new infection after treatment (odds ratio = 1.18, 95% confidence interval = 0.58, 2.40), suggesting these new infections were not the result of latent or persistent organism.

CONCLUSIONS

These data do not support a role for nasal secretions in causing reinfection after treatment. One mass topical treatment alone is unlikely to be effective in trachoma hyperendemic areas as shown by the rapid re-emergence of infection.