Activation of extracellular matrix metalloproteinases in equine laminitis

Samples of connective tissue obtained from the hoof of six laminitic and eight non-laminitic adult horses were analysed zymographically to investigate whether connective tissue matrix metalloproteinases are activated or induced during laminitis. The activity or matrix metalloproteinases was substantially greater in the tissues from the laminitic horses than in the tissues from the non-laminitic horses. A comparison of the collagenolytic activity in the laminitic and control tissues showed that collagenolytic activities corresponding to the 92 kDa (P < 0.001), 72 kDa (P < 0.01) and 66 kDa (P < 0.01) bands were induced in the laminitic tissues.     

Batimastat (BB-94) inhibits matrix metalloproteinases of equine laminitis

A method for culturing explants of lamellar hoof was developed to investigate the process of lamellar separation that occurs in laminitis. Explants, consisting of hoof wall, dermal and epidermal lamellae and the adjacent sub-lamellar connective tissue remained intact when cultured in tissue culture medium for 2 days. However, when cultured in the presence of the matrix metalloproteinase (MMP) activator aminophenylmercuric acetate (APMA), the lamellae separated when tension was applied by pulling the hoof wall in an opposite direction to the connective tissue. The separation occurred between the epidermal basal cells and the basement membrane therefore mimicking the lesion of laminitis. Electrophoresis of culture medium from control hoof explants into gradient polyacrylamide gels co-polymerised with gelatin revealed that the explants had produced 2 gelatinases of molecular weight 92 and 72 kDa corresponding to EqMMP-9 and EqMMP-2 respectively. Minor bands of lower molecular weight were the active forms of these enzymes. The zymograms of culture medium from APMA treated explants revealed an increase in the amount of active MMPs. Equine polymorphs cultured for 2 days produced only EqMMP-9. Lamellar explant medium from horses with acute laminitis contained increased amounts of zymogen and active EqMMP-2 and EqMMP-9 particularly in explants from the fore hooves. Zymography of homogenates of normal lamellar hoof tissue revealed only EqMMP-2 and a minor active band. However, homogenates of lamellar tissue from horses with laminitis showed that EqMMP-9 was present as well as increased EqMMP-2 in both zymogen and active forms. Addition of the MMP inhibitor batimastat (BB-94) to the culture medium of APMA treated explants prevented lamellar separation. BB-94 incubated with polyacrylamide strips containing the MMPs from laminitis affected lamellar explants inhibited enzymatic activity at a concentration of 1 mmol/l. It is concluded that activation of MMPs may be responsible for the lamellar separation seen in laminitis and that MMP inhibitors may be useful clinically for preventing this process.     

Parkinson's and Alzheimer's diseases: epidemiological comparison. 1. Descriptive aspects

Parkinson's (PD) and Alzheimer's (AD) diseases are age-related degenerative disorders that share common clinical, pathological and biochemical features. Epidemiological studies show similar age-specific incidence and prevalence curves, although PD tends to occur at earlier ages and, at old age, AD is more frequent. Both diseases are more common in western than in Mediterranean or Asiatic populations. These findings suggest that these diseases may have common determinants.     

A molecular epidemiological study of porcine rotaviruses

15-20% of the CF mutation are expected to be rare and escape detection by systems designed to screen for common mutations. The highly polymorphic simple repeats would be particularly useful for genetic diagnosis in CF families where the mutations have not been identified. In this study, we used denaturing gradient gel electrophoresis with psoralen-modified oligonucleotide primers to study the GTnTm polymorphism previously identified at the intron 8 - exon 9 junction of the CFTR gene. Twelve characteristic patterns were identified. The most frequent genotype in CF alleles was GT10T9 and in non-CF alleles GT11T7. In this study, the heterozygous incidence is 70% in unrelated CF carriers. This polymorphism is full informative in 45% and half-informative in 50%. We conclude, that this polymorphism, easy to study by a relatively simple, rapid and cheap procedure, would be particularly useful in genetic counselling for CF and prenatal diagnosis in CF families in which mutations have not been yet identified.     

Snowboard traumatology: an epidemiological study

OBJECTIVE: To estimate the frequency of perioperative morbidities in patients who underwent anesthesia and a surgical procedure with no preoperative laboratory testing. MATERIAL AND METHODS: We conducted an electronic database search of medical records of 56,119 patients who underwent surgical or diagnostic procedures and anesthesia at Mayo Clinic Rochester in 1994 and found 5,120 who had no laboratory tests done within 90 days before the procedure. From this group, we randomly selected 1,044 patients (87 from each month) to document the absence of preoperative tests, the presence of preexisting disease (by organ system), the type of anesthetic agent, and the outcomes and tests intraoperatively and postoperatively. RESULTS: The 1,044 patients ranged in age from 0 to 95 years (median age, 21). No deaths or major perioperative morbidities occurred (0.0%; exact 95% confidence interval, 0.00 to 0.35%). Although 10 patients underwent blood typing and screening for antibodies immediately preoperatively, no blood transfusions were necessary. Intraoperatively, 17 laboratory tests and 1 electrocardiogram were obtained, and 3 results were abnormal. Postoperatively, 42 blood tests and 2 electrocardiographic procedures were performed. Five of the 42 blood tests showed abnormal results (hemoglobin levels in 3, serum sodium in 1, and arterial blood gases in 1). One electrocardiogram showed normal findings, and the other revealed normal results except for premature ventricular contractions. No laboratory test done intraoperatively or postoperatively was found to change surgical or medical management substantially. One patient who had unanticipated blood loss during an outpatient procedure was admitted to the hospital for observation. CONCLUSION: All 1,044 patients, 97% of whom were relatively healthy, with no recent laboratory testing safely underwent anesthesia and an operation. We conclude that patients who have been assessed by history and physical examination and determined to have no preoperative indication for laboratory tests can safely undergo anesthesia and operation with tests obtained only as indicated intraoperatively and post-operatively. Current anesthetic and medical practices rapidly identify perioperative indications for laboratory evaluation as they arise.     

A clinical and epidemiological study of gastro-enteritis

Over a 13-year period, 2,903 Asian, Coloured and White children with gastro-enteritis were admitted to the Wilkins Infectious Diseases Hospital, Salisbury. During a pilot study of 250 patients conducted over the first 2 years, a definite seasonal variation in the occurrence of gastro-enteritis, with a peak incidence in winter, was noticed, and this led to a more detailed study of 2,653 patients over the next 11 years. Bacterial pathogens were recovered from 27% of patients, strains of Shigella accounting for 12% Salmonella for 7% and Escherichia coli for 8%. A severe outbreak of E. coli infection occurred between October 1971 and December 1972, and 4 of a total of 9 deaths occurred during this period, all in children suffering from E. coli 0111/B4 infections. The bacterial recovery rate was highest in the summer (40%) and lowest in the winter (12%). Winter diarrhoea broke out over 3-month periods during each year and accounted for 37% of the cases, but none of the children who contracted it died. The clinical picture of winter diarrhoea differed from the others and the most serious illness was that caused by enteropathogenic strains of E. coli. The over-all mortality in the series was 0,27%.     

Sero-epidemiological study on equine influenza in Japan

Ten male subjects performed five maximal treadmill running tests at 7 mph. Tests included two (test-retest) progressive, step increment (2 1/2% grade elevation), discontinuous tests (DCT); a progressive, step increment, continuous test (ct) and two constant load tests (CL and CL +2 1/2%). A DCT test was performed first for establishment of peak elevation levels as constant load tests were performed at the peak elevation level attained (CL) and at a level 2 1/2% higher (CL + 2 1/2%). The second DCT test and the remaining three tests were administered randomly. Peak preformance capability (operationally defined as duration at highest grade elevation) was markedly reduced during progressive tests as compared with constant load tests. There was a similar reduction in peak performance capability during the CT test as compared with DCT test. Maximal oxygen uptake (VO2max) was quite similar among the various tests. It was concluded that VO2max attained during progressive, step increment, tests is unaffected by cumulative submaximal work. Discontinuous and continuous progressive tests provide similar VO2max results.     

Cross-sectional epidemiological survey of rheumatoid arthritis patients seen in private practice in France. Descriptive results (1629 cases)

OBJECTIVE: To conduct an epidemiological study of rheumatoid arthritis patients seen by office-based rheumatologists in France (first semester of 1996). METHODS: Cross-sectional study of 1629 rheumatoid arthritis patients conducted by 373 office-based rheumatologists who volunteered for the study (one visit per patient). Each rheumatologist was to complete a 200-variable questionnaire for the first four rheumatoid arthritis patients who came to their office. RESULTS: Women contributed 81% of the sample (mean age, 57 years); 19% of patients were seen in the Paris area, 20% in the North East, 20% in the North West, 22% in the South East and 19% in the South West. Twenty-nine per cent of patients had a paid job and 21.1% (all women) were homemakers. Among the patients with a paid job, 44% were on sick leave, with the reason for the sick leave being the rheumatoid arthritis in 36% of cases. Nineteen per cent of patients had stopped working permanently because of their rheumatoid arthritis, after a mean disease duration of six years. Mean disease duration in the overall sample was eight years. The diagnosis was established within six months of symptom onset in 75% of cases. A family history of rheumatoid arthritis was found in 11% of patients and a family history of other autoimmune diseases in 2%. The disease was precipitated by a stressful life event in 17% of cases. Follow-up was being provided only by the study rheumatologist in 59% of cases and also by a general practitioner in 39%. The disease was quiescent in 9% of cases, minimally active in 32%, moderately active in 46% and severely active in 13%. Eighty-four per cent of patients were on one (78%) or more (6%) second-line drugs including methotrexate (45%), an antimalarial (17%), intramuscular gold (14%), tiopronin (9%), D-penicillamine (6%) and sulfasalazine (12%). Fifty-two per cent of patients were on steroid therapy (mean dose, 7.5 +/- 5.7 mg/d). Other drugs included nonsteroidal antiinflammatory agents (61%), analgesics (61%), gastroduodenal protective agents (45%) and anxiety-relieving agents (10%). Twenty-four per cent of patients had had one or more surgical procedures (mean, 3/patient) for their joint disease. CONCLUSION: This nation-wide epidemiological survey conducted in France provides a database on the socioeconomic and demographic characteristics of rheumatoid arthritis patients followed in private practice.     

A post mortem study of equine digital flexor tendons

The results of a survey are presented in which 589 limbs from 206 horses were dissected. In174 of the limbs lesions were found in either the superficial (131) or deep (43) digital flexor tendons. Changes occurring with age were also recorded. The sites of the abnormalities and their macroscopical appearance are described and the value of the results is considered in relation to the diagnosis and the treatment of clinical lesions.     

Descriptive study of bowel care practices and equipment in spinal cord injury

46% of the 277 SCI veterans responding to the survey used bowel care/shower chairs at home. Of those who regularly used these chairs (N = 147), over 66% felt their safety was compromised by their use. Caregivers reported similar dissatisfaction with existing bowel care/shower chairs. Primary concerns related to difficulty in assisting with safe transfers were, lack of hand access to perianal area for digital stimulation, lack of ease in rolling and turning the chair, difficulty in keeping the chair clean, and lack of durability of chair, particularly with brakes and seat. Primary safety risks included patient falls and pressure ulcer development. Reports of chair related patient falls (35%) and pressure ulcers (24%) were common in the SCI patients surveyed. Less than 54% were satisfied with the design and usability of bowel care/shower chairs.     

Haematological changes during development of acute laminitis hypertension

Experimental carbohydrate overload of 15 horses resulted in consistent haematological changes during development of laminitis hypertension. Significant alterations in packed cell volume, leucocyte differential count, serum glucose levels and protein values occurred before onset of Obel grade 3 lameness and hyperkinetic circulatory state. Blood platelets were significantly decreased 8 h after the onset of severe lameness. Findings in this study were indicative of haemoconcentration due to compartmental fluid shifts and leucocytic stress response consistent with increased circulating adrenoglucocorticoids and/or catecholamines.     

Handball injuries. An epidemiological and socioeconomic study

A total of 570 injuries in handball players were prospectively registered in a well-defined geographical area of 124,321 inhabitants. The incidence of handball injuries was 46/10,000 inhabitants/year and in females (61/10,000/year) double that for males (31/10,000/year). Sixty-two percent of the injuries were distortions and sprains and 12% were fractures. A total of 7% were hospitalised and the loss of income because of sick leave was in total $3870. Sixty-eight percent of the injured handball players did not play for more than one week. Surprisingly, 8% of the minor injuries resulted in a risk leave of more than six days. Five percent of these injured quit a tournament of training after sustaining a handball injury.     

Prospective epidemiological study of rheumatism in the Irkutsk Region

The changes in the prevalence and primary incidence of rheumatism in the region were analyzed by the epidemiological surveys and notifications made in 1961 to 1994. During this period, the primary incidence rates showed a 70-fold decrease, mainly due to those among females and children. The paper presents changes in the pattern of risk factors of rheumatism and defines the prevalence decrease rate of rheumatism in three follow-up periods. A comprehensive rehabilitation programme for rheumatic patients has been worked out.     

Determinants of participation in an epidemiological study of preterm delivery

We describe the study design and patterns of participation for a cohort study of preterm delivery, focused on genital tract infections, nutrition, tobacco use, illicit drugs and psychosocial stress. Women are recruited at 24-29 weeks' gestation from prenatal clinics at a teaching hospital and a county health department. We recruited 57% of the first 1843 eligible women; 29% refused and 8% could not be contacted. White women were somewhat more likely to participate than African-American women (61% vs. 54% respectively). More notable differences were found comparing teaching hospital and health department clinics (71% vs. 47% participation respectively), with the health department clinic having a greater proportion refuse (24% vs. 33%) and more women who could not be contacted (4% vs. 11%). Participation was affected only minimally by day or timing of recruitment, but inability to contact diminished substantially as the study continued (13-0%). Refusals were largely unrelated to patient attributes. Lower education predicted inability to contact. Risk of preterm delivery was 14% among recruited women, 10% among women who refused, and 15% among women whom we were not able to contact, demonstrating that, overall, risk status was not lower among recruited women.     

An epidemiological study of patterns of condylar fractures in children

OBJECTIVE: To find out how the site and type of condylar fracture are affected by its aetiology and the age and sex of the patient. DESIGN: Retrospective study. SETTING: Tertiary referral centre, Finland. MATERIAL: Radiographs of 101 children (aged 15 years or less) with 119 condylar fractures. MAIN OUTCOME MEASURES: Site of fracture and degree of displacement. RESULTS: A total of 26 of the 119 fractures were intracapsular (22%) and 93 (78%) extracapsular. Only among patients less than 6 years of age was there a preponderance of intracapsular fractures (7/12 fractures in 10 patients, 58%). In the older children 78% (83/107) were in the condylar neck. There were few subcondylar fractures (5/119, 4%). Only 6 fractures were displaced (5%). Dislocation of the condyle from the glenoid fossa was common in all age groups. CONCLUSION: The site of condylar fracture is age related, but not associated with sex or aetiology.     

The transmission of campylobacter in piggeries; an epidemiological study

Epizootics of Rift Valley fever (RVF) are often associated with periods of heavy rainfall, which are favorable for mosquito vectors. However, in seasons with normal or low rainfall, enzootic circulation occurs, suggesting the existence of a natural host that can act as a cryptic carrier during interepizootic periods. To confirm the role of heavy rainfall in epizootic circulation, and to identify a possible natural host of RVF virus, serum samples from small terrestrial mammals in the Free State and Northern Cape regions of South Africa were collected before and after the 1988 floods. These areas are known to support epizootic circulation of RVF virus. The samples were tested for the presence of RVF virus-specific IgG using an ELISA and positive sera were confirmed by a neutralization test. Forty-seven (15%) of 312 Aethomys namaquensis (Namaqua rock rat) had antibodies to RVF virus. Of these positive sera, nine (6%) of 141 were collected before the floods of 1988 and 38 (22%) of 171 were collected afterwards (P = 0.001). Naive A. namaquensis were inoculated with RVF virus and developed a viremia, but no clinical symptoms, suggesting that they can act as temporary asymptomatic carriers of the virus. These results suggest a role for A. namaquensis as a cryptic carrier for RVF virus during interepizootic periods and support the results of other studies suggesting an amplifying role for heavy rainfall in the circulation of RVF virus.