Expression and secretion of pertussis toxin subunit S1 in Bacillus subtilis

Pertussis toxin (PT) is an important virulence determinant of Bordetella pertussis and one of the major protective antigens against whooping cough. The genes coding for PT have recently been cloned, but attempts to express them in Escherichia coli have been unsuccessful. We therefore explored the possibility of expressing these genes in Bacilius subtilis for which efficient vectors are available. The lack of endotoxin in the Gram-positive Bacillus might be an additional advantage for the production of a vaccine component. A DNA fragment coding for S1, one of the subunits of pertussis toxin, was inserted into an alpha-amylase secretion vector and the recombinant plasmid was introduced into B. subtilis. This resulted in high expression of S1, most of which was secreted and therefore found in the culture supernatant. This supernatant had ADP-ribosylating activity similar to that of PT. Western blot with antiserum to B. pertussis holotoxin showed several proteins ranging in size from 28 kDa to 20 kDa reacting in specific manner. About 10% of the protein recognized by the antiserum was of the size expected for native-size S1. The total amount of S1 proteins (full size and truncated) in the culture supernatant was about 100 mg/l. S1 protein made in B. subtilis was partially purified using chromatography with P-cellulose and Blue Sepharose. This preparation was used to immunize rabbits; the immune serum thus obtained recognized subunit S1 of native pertussis toxin.     

Intraarticular Injection of High-Molecular Hyaluronic Acid: An Experimental Study on Normal Adult Rabbit Knee Joints

High-molecular hyaluronic acid was injected repeatedly into normal knee joints of adult rabbits. Histologically the articular cartilage was not affected by this treatment. The content of chondroitin sulphate, assessed by a histochemical method, was not altered and neither was the water content of the hyaline articular cartilage. on the other hand, in the synovial membrane of joints treated with hyaluronic acid a diffuse infiltration of plasma cells and lymphocytes was observed, indicating that the hyaluronic acid administered exerts its action via the synovial membrane.     

Refusing to be ill: a longitudinal study of patients' experiences of asthma/allergy

Purpose : The purpose of this study was to search for a deeper understanding of the ways patients with asthma/allergy experience their illness situation. Method : Thirty patients with a history of airway symptoms on allergen exposure and a positive skin prick test were included in the study. They took part in open-ended interviews in their homes twice at an interval of eight years, according to the phenomenographic approach. Results : Fourteen different categories of experience were identified: 'knowing for oneself', 'body related', 'environment related', 'psychosomatic', 'magic', 'fatalism', 'compliance with medication', 'alternative medicine', 'health care', 'provocation', 'avoidance', 'normalization', 'normification' and 'pursuing life'. The analysis also showed that these categories, to varying degrees, were an expression of a desire to retain an ordinary healthy identity and its value. The longitudinal results showed that with time the patients distanced themselves from the medical perspective and found their own ways of thinking and acting in relation to their ill health, which is seen as strengthening for the identity. Conclusions : The different, individual ways patients with asthma/allergy developed in relation to the illness situation have a preserving effect on the identity, which ought to be considered in patient education and rehabilitation.     

The extrinsic fibrinolytic system in survivors of myocardial infarction

The extrinsic fibrinolytic system was assessed among 124 consecutive survivors of acute myocardial infarction below 70 years of age. In samples drawn 3 months after discharge from hospital, the PAI-1 levels were higher and the tPA activities were lower than among elderly healthy controls. In contrast, the AMI survivors had higher tPA antigen levels at rest and after venous occlusion, and higher tPA activities after venous occlusion. Among patients having PAI-1 levels >10 IU/ml, there was a positive correlation between PAI-1 and serum triglycerides, and a negative correlation between PAI-1 and age; this group was also significantly younger than the subgroup having <-10 IU/ml of PAI-1.

There were thus multiple disturbances of the extrinsic fibrinolytic system among these patients. As cardiovascular risk factors, these disturbances appear to be relatively more important the younger the patients are.     

Impact of a community-based osteoporosis and fall prevention program on fracture incidence

Associations between a 10-year community-based osteoporosis and fall prevention program and fracture incidence amongst middle-aged and elderly residents in an intervention community are studied, and comparisons are made with a control community. A health-education program was provided to all residents in the intervention community, which addressed dietary intake, physical activity, smoking habits and environmental risk factors for osteoporosis and falls. Both communities are small, semi-rural and situated in Östergötland County in southern Sweden. The analysis is based on incidences of forearm fractures in the population 40 years of age or older, and hip fractures in the population 50 years of age or older. Data for three 5-year periods (pre-, early and late intervention) are accumulated and compared. In the intervention community, forearm fracture incidence decreased in women. There are also tendencies towards decreasing forearm fracture incidence in men, and towards decreasing trochanteric hip fracture incidences in women and in men in the late intervention period. No such changes in fracture incidences are found in the control community. Cervical hip fracture incidence did not change in the intervention and the control communities. Although the reported numbers of fractures are small (a total of 451 forearm and 357 hip fractures), the numbers are based on total community populations and thus represent a true difference. The decrease in forearm fracture incidence among women, and the tendency towards decreasing trochanteric hip fractures, in contrast to the absence of change in cervical hip fractures, might be mainly due to a more rapid effect of fall preventive measures than an increase in bone strength in the population. For the younger age groups an expected time lag between intervention and effect might invalidate the short follow-up period for outcome measurements. Thus, the effect of the 10-year intervention program on fracture incidence should be followed during an extended post-intervention period.     

Common biochemical markers of bone turnover predict future bone loss: a 5-year follow-up study

BACKGROUND: Bone mineral density (BMD) is used to follow gain or loss of bone mass but cannot detect changes within a short period of time. Biochemical markers of bone turnover may be of value for prediction of individual bone loss. METHODS: We studied the relation between common inexpensive markers of bone turnover (serum alkaline phosphatase (ALP), osteocalcin (OC), urinary hydroxyproline (OHPr), and calcium (Ca)), BMD, age, and menopause in a combined cross-sectional and longitudinal design comprising 429 pre- and postmenopausal randomly selected women aged 21-79 years (mean 50 years). A follow-up was initiated after 5 years (including 192 of these women), which focused on changes in bone mass and the ability of these four common markers of bone turnover (sampled at baseline) to predict future bone loss. RESULTS: A marked increase was observed for all markers at the beginning of menopause. During the postmenopausal period ALP and Ca decreased to near premenopausal levels, while OC and OHPr remained high even 15 years after menopause. We also found inverse correlations at baseline between the bone markers and BMD, independent of the selected marker or skeletal site, r=-0.14 to -0.46, P<0.05. The correlations between ALP, OC, OHPr, and subsequent bone loss over 5 years, was significant for arm, r=-0.23 to -0.36, P<0.01. Baseline levels of all bone markers correlated significantly at group level with the 5-year follow-up of BMD for all sites. The ability of markers to predict individual bone loss was estimated by a multivariate regression model, which included baseline BMD, age, and body mass index as independent variables. ROC analysis showed a validity of approximately 76% for the forearm model, but was lower for the hip (55%) and lumbar spine (65%). CONCLUSIONS: These data show that the common inexpensive biochemical markers of bone turnover ALP, OC, OHPr, and Ca were related to the current bone mass and, moreover, provides information about future bone loss at the individual level. Future investigations should include an evaluation of the clinical relevance of markers of bone turnover in relation to fracture risk.     

Comparison of two self-rating scales to detect depression: HADS and PHQ-9

Background

More than half of patients with depression go undetected. Self-rating scales can be useful in screening for depression, and measuring severity and treatment outcome.

Aim

This study compares the Hospital Anxiety and Depression Scale (HADS) and the Patient Health Questionnaire (PHQ-9) with regard to their psychometric properties, and investigates their agreement at different cut-off scores.

Method

Swedish primary care patients and psychiatric outpatients (n = 737) who reported symptoms of depression completed the self-rating scales. Data were collected from 2006 to 2007. Analyses with respect to internal consistency, factor analysis, and agreement (Cohen''s κ) at recommended cut-offs were performed.

Results

Both scales had high internal consistency (α = 0.9) and stable factor structures. Using severity cut-offs, the PHQ-9 (≥5) diagnosed about 30% more patients than the HADS depression subscale (HADS-D; ≥8). They recognised the same prevalence of mild and moderate depression, but differed in relation to severe depression. When comparing recommended screening cut-offs, HADS-D ≥11 (33.5% of participants) and PHQ-9 ≥10 (65.9%) agreement was low (κ = 0.35). Using the lower recommended cut-off in the HADS-D (≥8), agreement with PHQ-9 ≥10 was moderate (κ = 0.52). The highest agreement (κ = 0.56) was found comparing HADS-D ≥8 with PHQ-9 ≥12. This also equalised the prevalence of depression found by the scales.

Conclusion

The HADS and PHQ-9 are both quick and reliable. The HADS has the advantage of evaluating both depression and anxiety, and the PHQ-9 of being strictly based upon the Diagnostic and Statistical Manual of Mental Disorders. The agreement between the scales at the best suitable cut-off is moderate, although the identified prevalence was similar. This indicates that the scales do not fully identify the same cases. This difference needs to be further explored.     

Patient education and group counselling to improve the treatment of depression in primary care: a randomized controlled trial

BACKGROUND: The Contactus program for depressed patients in primary care, consists of six lectures about depression, each followed by a group discussion. The aim of this study was to investigate if Contactus can improve treatment outcome in comparison to a control group. METHODS: Forty-six primary care centres in Sweden, each randomly allocated either to the Contactus group or to the control group, included depressed patients, 205 in the Contactus group and 114 in the control group. Besides regular treatment of depression, the Contactus group participated in the educational program. At start and after 6 weeks, patients filled in a questionnaire and the self-reports: HADS (Hospital Anxiety and Depression Scale) and GAF-self (Global Assessment of Functioning). RESULTS: After 6 weeks, clinically depressed patients (HAD-depression score >10) had a mean improvement in HAD-D of 4.6 in Contactus vs. 3.0 in controls (p=0.02), and 72% vs. 47% considered themselves to feel better (p=0.01). Increase in GAF score was 11.8 vs. 5.8 (p=0.04), respectively. According to HADS, 55% in Contactus were responders vs. 29% among controls (p=0.006), and 42% vs. 21% (p=0.02) were in remission. LIMITATIONS: Only 40% of the patients in Contactus and 35% among controls were clinically depressed according to the HADS (>10 points) at inclusion. CONCLUSIONS: Patient education and group counselling contributes significantly to better improvement among depressed patients. Group treatment is inexpensive and could be implemented in the routine care of depressed patients in primary care.