Pseudophakia and Lens Opacities in 70-Year-Olds in Gothenburg, Sweden; Gender Differences, Impact on Self-Reported Visual Function and Validation of Self-Reported Cataract and Pseudophakia

Purpose

The study aimed at determining the prevalence and sex differences in cataract, pseudophakia, lens opacities and self-reported cataract in 70-year-old people in Gothenburg, Sweden. The purpose was also to identify correlations between lens opacities, visual acuity and subjective visual function, and to validate self-reported cataract and cataract surgery.

Patients and Methods

Population-based cross-sectional study where participants (n=1182) answered questions about self-reported diagnosis of cataract and cataract surgery. A total of 1139 subjects completed the National Eye Institute Visual Functioning Questionnaire-25 (NEI VFQ-25), 560 subjects underwent ophthalmic examination including visual acuity and lens photography. t-test, Pearson chi-square and Mann-Whitney U-test were used for obtaining p-values. ANOVA (analysis of variances, Kruskal-Wallis, one-way) was used to compare VFQ-25 between 3 groups; no cataract, cataract and pseudophakia. To clarify the differences between specific pairs of groups post-hoc test (Bonferroni) was used after ANOVA.

Results

Self-reported cataract was more common in women than in men (27.2% vs 19.1%, p=0.001, chi-square). Cataract surgery was reported by 16.3% of women and 12.6% of men (p=0.072). Upon eye examination, the prevalence of pseudophakia was 16.9% in women compared to 10.2% in men (p=0.020). The prevalence of cataract, including pseudophakia, was 31.9% in women versus 23.8% in men (p=0.033). Significant correlations (Spearman's rho) were found between lens opacities and visual acuity. Self-reported cataract surgery showed a very high specificity and high sensitivity. The composite score from NEI VFQ-25 was lower in people with pseudophakia than in people with/without cataract (p=0.012, Kruskal-Wallis).

Conclusion

The prevalence of cataract including pseudophakia in 70-year-olds in Gothenburg is higher compared to previous studies in similar geographical areas. Also, it is more common in women than in men. The lack of significant sex differences in lens opacities may be due to cataract surgery at an earlier stage. Validation showed very good agreement between pseudophakia and self-reported cataract surgery.

The life circumstances of persons with a psychiatric disability: a survey in a region in southern Sweden

This article describes the life circumstances of persons with a psychiatric disability living in one urban and six rural areas in a single region in Sweden. Furthermore, the life circumstances of persons with a psychiatric disability are discussed in relation to the aims of social policies in Sweden. Data were collected by means of a survey study exploring the formal support provided by local authorities to its citizens and the informal support given by family members and volunteers. The results reveal how the respondents themselves describe their life circumstances in terms of their living conditions, occupation and activities, health, and formal and informal support. The results indicate that persons with a psychiatric disability, regardless of where they live, need both formal and informal support in order to cope with their everyday lives. The family plays an important role in this, and it is essential for the formal and informal support systems to cooperate with each other. The lack of activities and opportunities for work experienced by persons with a psychiatric disability indicates that the sociopolitical goal of fostering access to employment and work and to earning a living for this group is far from having been attained.

Highly sensitive polymer-based cantilever-sensors for DNA detection

We present a technology for the fabrication of cantilever arrays aimed to develop an integrated biosensor microsystem. The fabrication process is based on spin coating of the photosensitive polymer and near-ultraviolet exposure. Arrays of up to 33 microcantilevers are fabricated in the novel polymer material SU-8. The low Young's modulus of the polymer, 40 times lower than that of silicon, enables to improve the sensitivity of the sensor device for target detection. The mechanical properties of SU-8 cantilevers, such as spring constant, resonant frequency and quality factor are characterized as a function of the dimensions and the medium. The devices have been tested for measurement of the adsorption of single stranded DNA and subsequent interstitial adsorption of lateral spacer molecules. We demonstrate that sensitivity is enhanced by a factor of six compared to that of commercial silicon nitride cantilevers.

A double-blind placebo-controlled study of the effects of amphetamine and physiotherapy after stroke

Major therapeutic advances in the rehabilitation of subacute stroke are lacking. One promising approach is treatment with amphetamine in combination with physiotherapy so as to promote motor function. In a randomized, double-blind, placebo-controlled clinical trial, the effect of 10 sessions with 10 mg of amphetamine combined with physiotherapy during a 5-week period was investigated in 39 geriatric patients who had been admitted to a stroke rehabilitation unit. Motor function (Fugl-Meyer motor performance score) and activities of daily living (ADL; Barthel's index) were assessed at baseline and at the end of treatment. All patients improved significantly over the intervention period. Amphetamine-treated patients did not show any increase in motor function or ADL as compared to the control group. Rehabilitation with amphetamine at this dosage and interval, combined with physiotherapy, did not promote motor recovery or functional capacity in patients suffering from stroke.

Reliability and reproducibility of brain tissue volumetry from segmented MR scans

Reliable measurement of different tissue volumes in the living brain is of great importance for human brain research. In this article, we report on the inter- and intraoperator reliability and scan-rescan reproducibility of segmented intracranial tissue volumes from MR images using the image analysis software suite BRAINS. The absolute data of tissue volume measurements are also presented. The reliability and consistency of the measurements of the segmented volumes were excellent. The segmentation is robust and rapid and the volume measurements are plausible and suitable for quantitative studies in clinical brain research.

["To suffer an ordeal": Some Swedish physicians' struggle during the nineteenth century against unhygienic female dress]

Tight-lacing of the female body has been practised at various periods in the history of costume. During the romantic age of the nineteenth century the ideal women had to be pale, weak and often pathologically thin. She was supposed to be of a humble disposition and subservient to her husband (according to the doctrine of subordination). Women laced themselves so tightly that their bodies became deformed, with physical injuries and damage to the internal organs as a consequence. Competition for suitable husbands was keen, since marriage was the only honourable way for a woman to ensure that she would be provided for. It was also in the nineteenth century that doctors were beginning to fight against endemic disease and to argue for a more hygienic way of life. They maintained that women were slaves to fashion and that they dressed in an unhygienic way. Above all, they campaigned against the use of tight-laced corsets. Swedish doctors, such as Anton Nyström, Truls Johan Harterlius and Karolina Widerström headed the fight against the use of laced corsetes, on both medical and social grounds. An improved and "informed" costume was introduced which was meant to allow women greater freedom of movement, thus enabling them to live a more natural life. It was, however, not until 1910 that the tightly-laced corset was abandoned. The conclusion of this is that the history of costume is "the history of absurd follies".

Elevated antibody levels to Epstein-Bbarr virus antigens in patients with hairy cell leukemia compared to controls in relation to exposure to pesticides, organic solvents, animals, and exhausts

Epstein-Barr virus (EBV) is a B-lymphotropic human herpes virus infecting B-cells, which has been associated with lymphoid malignancies, above all non-Hodgkin lymphomas (NHL). Severe immunosuppression is the best recognized risk factor for NHL. Many factors in the environment that have been described as risk factors for NHL cause measurable changes in immune functions. Hairy cell leukemia (HCL) is a rare, indolent non-Hodgkin lymphoma, originating from B-lymphocytes. This was a case-control study including 111 male cases with HCL and 400 controls. In a subgroup of 57 cases and 65 controls analysis of antibodies to EBV early antigen, viral capsid antigen, and EBNA-1, measured as P107, was performed. In this study, we confirm other studies describing elevated levels of antibodies to the EBV early antigen (EA) in patients with HCL compared to controls. We found only minor differences in the levels of antibodies to the viral capsid antigen (VCA) and EBNA-1. measured as P107. We found a positive association of a titer to EA IgG > or =40 (OR 4.1; CI 1.9-9.5). The ORs were further elevated when subjects with high levels of EA IgG and exposed to environmental agents such as organic solvents, certain pesticides, impregnating agents, animals, and exhausts were compared to those subjects with low levels that were not exposed. Antibody reactivity against the EBV EBNA 1-alanine-glycine repeat (P107 IgG) above the median gave an increased OR for HCL, which further increased in subjects exposed to organic solvents, certain pesticides. impregnating agents, animals, and exhausts. However, the numbers of exposed cases and controls were small in some of the calculations.

Concentrations of organochlorines related to titers to Epstein-Barr virus early antigen IgG as risk factors for hairy cell leukemia

Hairy cell leukemia (HCL) is a rare chronic B-cell malignancy that, according to modern classifications, is a subgroup of non-Hodgkin lymphomas (NHLs). A rapid increase in incidence of NHL has been reported in many countries. The reasons for this increase are largely unknown, but exposure to organochlorines has been suggested as a risk factor. Epstein-Barr virus is a human herpesvirus that has been associated with certain subgroups of NHL. In this study, we measured lipid adjusted blood concentrations (in nanogram per gram) of 36 congeners of polychlorinated biphenyls (PCBs), p, p'-dichlorodiphenyldichloroethylene (p,p'-DDE), hexachlorobenzene (HCB), and four subgroups of chlordanes (trans-nonachlor, cis-nonachlor, MC6, and oxychlordane) in incident cases of HCL and controls from the general population. We obtained results on organochlorines and antibodies for 54 cases and 54 controls. Titers of antibodies to the Epstein-Barr early antigen and Epstein-Barr nuclear antigen, measured as P107, were correlated to concentrations of organochlorines to evaluate the possibility of an interaction between these factors in the pathogenesis of HCL. We found no significant difference in lipid-adjusted blood concentrations of total PCBs, p,p'-DDE, HCB, or the sum of the chlordanes between cases and controls. Titers of antibodies to Epstein-Barr early antigen IgG [Greater and equal to] 40 were correlated to an increased risk for HCL. This risk was further increased in those with a level above the median value of p,p'-DDE, HCB, or the sum of the chlordanes, suggesting an interaction between Epstein-Barr virus and a higher concentration of these chemicals. We also found increased risk for the sum of immunotoxic PCB group.

Age and cystathionine beta-synthase activity in cultured fibroblasts from patients with arterial and venous vascular disease

In order to determine if cystathionine beta-synthase (CBS) could separate groups of patients with various vascular disease, CBS activity was studied in cultured human skin fibroblasts from 30 subjects being either controls, atherosclerotic patients or patients having suffered a deep venous thrombosis. We found a tendency to a negative correlation between age and CBS activity in the control group only (r = -0.58, P = 0.08), with a tendency to lower CBS activities in the young patients with atherosclerotic (4.9) or venous disease (5.3) compared to the young control group (10.2). This could implicate higher levels of p-homocysteine with increased age as well as in young patients with atherosclerotic or thrombotic disease causing vascular damage. The results are important for the further discussion of the role of homocysteine as a risk factor for developing atherosclerotic and thrombogenic vascular disease and for finding a suitable screening method as prevention is by vitamin supplement only.

Venous Insufficiency 4 Years after an Episode of Deep Vein Thrombosis: A Clinical and Plethysmographic Investigation

Objective:

To evaluate the frequency of venous insufficiency following deep vein thrombosis (DVT).

Design:

Follow-up 4 years after a verified DVT.

Setting:

University hospital in Malmö.

Patients:

Eighty-seven subjects with venographically verified DVT.

Main outcome measure:

To compare venous function in legs, with and without previous DVT, by venous straingauge plethysmography and its correlation with clinical symptoms and signs.

Results:

Fifty-two per cent of patients described general discomfort from the thrombotic leg at follow-up. Active leg ulcers were found in three patients (3%); there were no signs of venous insufficiency in 33% at clinical examination. Thirty-seven patients (75%) with ≥ 1 cm difference in calf circumference between the thrombotic and contralateral leg had suffered a proximal DVT. The refilling time T90 was pathological in 67% and the muscle pump function (RV) in 55%. In the nonthrombotic leg the corresponding figures were 53% and 40%. Nevertheless a positive correlation was found between RV of the thrombotic leg and the contralateral leg ( r = 0.33) but an even stronger correlation was found for T90 ( r = 0.74).

Conclusion:

Venous insufficiency was found in 60% of legs 4 years after DVT but was also found in 14% of legs without previous thrombosis. This may be caused not only by effects of the thrombosis but also by the ageing process.

Occupational exposures, animal exposure and smoking as risk factors for hairy cell leukaemia evaluated in a case-control study

To evaluate occupational exposures as risk factors for hairy cell leukaemia (HCL), a population-based case-control study on 121 male HCL patients and 484 controls matched for age and sex was conducted. Elevated odds ratio (OR) was found for exposure to farm animals in general: OR 2.0, 95% confidence interval (CI) 1.2-3.2. The ORs were elevated for exposure to cattle, horse, hog, poultry and sheep. Exposure to herbicides (OR 2.9, CI 1.4-5.9), insecticides (OR 2.0, CI 1.1-3.5), fungicides (OR 3.8, CI 1.4-9.9) and impregnating agents (OR 2.4, CI 1.3-4.6) also showed increased risk. Certain findings suggested that recall bias may have affected the results for farm animals, herbicides and insecticides. Exposure to organic solvents yielded elevated risk (OR 1.5, CI 0.99-2.3), as did exposure to exhaust fumes (OR 2.1, CI 1.3-3.3). In an additional multivariate model, the ORs remained elevated for all these exposures with the exception of insecticides. We found a reduced risk for smokers with OR 0.6 (CI 0.4-1.1) because of an effect among non-farmers.

Autopsy-verified venous thromboembolism within a defined urban population--the city of Malmö, Sweden

OBJECTIVE

To analyse the frequency of autopsy-proven venous thromboembolism within a defined region and evaluate if certain risk groups not earlier recognized could be found. The incidence of objectively diagnosed venous thromboembolism was also calculated.

SETTING

The city of Malmö, Sweden, with 230,000 inhabitants.

MAIN OUTCOME MEASURE

Analysis of 2,356 autopsies for the year 1987 of deceased inhabitants from the city of Malmö (2,981 deceased, autopsy frequency 79.0%) regarding venous thromboembolism.

RESULTS

25% of autopsies revealed venous thromboembolism. At the acute-care hospital 31%, at the chronic hospital 37%, but in forensic autopsies of non-hospital deaths only 5% (p<0.001) revealed venous thromboembolism. Major pulmonary embolism was seen in 13% and was more frequent in in-hospital deaths (p<0.001). Two in-hospital and two non-hospital deaths due to pulmonary embolism and fractures were found: two patients with knee fractures, one hip fracture and one ankle fracture patient. The incidence of objectively diagnosed venous thromboembolism (autopsy, phlebography, perfusion scintigraphy) was calculated and an incidence of 42.5/10,000 inhabitants/year was found, (strongly age-dependent).

CONCLUSION

Venous thromboembolism is a common finding in autopsies of hospitalized patients. Patients with fractures other than hip fractures are less well studied as regards venous thromboembolic complications. Further studies on these fracture patients are warranted.

Occupation and occupational exposure to UV light as risk factors for hairy cell leukaemia evaluated in a case-control study

To investigate the role of occupation as a risk factor for hairy cell leukaemia a case-control study on 121 male, hairy cell leukaemia (HCL) patients, and 484 controls matched for age and sex, was conducted. We found significantly elevated risk for HCL among building painters (OR, 5.7; 95% CI, 1.6-20.8; based on six cases and four controls) and construction workers (OR, 3.3; CI, 1.2-9.2; based on seven cases and eight controls). Farming has been suggested as a risk factor in HCL. In this investigation farmers had an OR of 1.2 (CI, 0.6-2.3) and farm workers an OR of 1.5 (CI, 0.8-2.8). However, having ever worked in farming yielded an OR of 1.8 (CI, 1.1-2.9). Having grown up mainly in a rural area gave an OR of 1.4 (CI, 0.9-2.4). UV light has been suggested as a risk factor for non-Hodgkin's lymphoma (NHL). To evaluate the impact of UV exposure, classification of occupations as indoor, outdoor or mixed indoor/outdoor was made. Outdoor and mixed outdoor/indoor work yielded ORs of 2.3 (1.0-4.9) and 1.6 (1.0-2.5), respectively. When the effect of outdoor/indoor or mixed indoor/outdoor work was analysed using a scoring system the OR was 2.0 (CI, 0.9-4.4) for farmers compared with 0.8 (CI, 0.3-1.9) among non-farmers in the highest scoring group. There was no clear correlation between socioeconomic status as defined by the Swedish Socio-Economic Classification (SEI), and the risk of HCL. As many comparisons were made, the possibility of associations occurring by chance can not be excluded.

Deep venous thrombosis and occult malignancy: an epidemiological study

OBJECTIVE

To determine the risk of subsequent cancer in patients with deep venous thrombosis confirmed by venography.

DESIGN

Follow up of all patients who had venography for suspected deep venous thrombosis during 1984-88. Patients were traced through a cancer registry up to 1 January 1991.

SUBJECTS

4399 patients who had phlebography in one hospital.

SETTING

General hospital in Malmö, Sweden, serving a population of 230,000.

MAIN OUTCOME MEASURE

Number of cancers recorded.

RESULTS

4399 patients had venography for suspected deep venous thrombosis; 604 were known to have a malignancy at the time of venography and were excluded from further analysis. 1383 had deep venous thrombosis, 150 of whom subsequently developed cancer. 182 of the 2412 patients without thrombosis developed cancer. During the first six months after venography 66 patients with thrombosis developed malignancy compared with 37 patients without thrombosis (P < 0.0001). 38 of the cancers in the deep venous thrombosis group were detected by history, physical examination, and laboratory tests. Three patients had postoperative or post-traumatic deep venous thromboses. Only two of the remaining patients would have benefited from early detection by extensive screening. After six months the incidence of cancer was identical in patients with and without thrombosis.

CONCLUSION

Deep venous thrombosis is associated with a significantly higher frequency of malignancy during the first six months after diagnosis. Malignancies can be found with simple clinical and diagnostic methods and extensive screening is not required.

Cadmium in blood in Alzheimer's disease and non-demented subjects: results from a population-based study

Blood cadmium concentrations were studied in Alzheimer's disease (AD) and non-demented subjects. The 29 individuals were randomized from the ongoing population survey on ageing and dementia in Stockholm, the Kungsholmen Project. Smokers had, as expected, higher cadmium levels than non-smokers. Cadmium concentrations in blood were related to diastolic blood pressure in non-smoking, non-demented individuals. In contrast to previous reports no differences in blood cadmium levels were found between AD sufferers and non-demented subjects. Furthermore, there were no correlations between cadmium levels in blood and age or cognitive functions. The importance of quality assurance in sample collection and analysis of cadmium as well as scrutinizing smoking habits is emphasized.

Release of beta-hexosaminidase isoenzymes in cultured human fibroblasts

We have used enzyme immunoassay methods to study the intra- and extracellular isoenzyme pattern of beta-hexosaminidase (Hex) in human fibroblast cultures. The released activity into the medium during 24 h was about 10% of the intracellular activity. Intra- and extracellular ratio of Hex B to total Hex (Hex A plus Hex B) was about one-third. Estimation of the molecular weight of the released activity showed that it corresponded to 150 kDa, which is equal to the high molecular mass precursor forms of the enzyme. NH4Cl is known to disturb the intracellular transport of lysosomal enzymes and increase the secretion of newly synthesized precursor forms. Addition of NH4Cl even at 3 mM resulted in an increased release of total Hex, which was already noted within 24 h. We speculate that the increased concentration of plasma NH4+ in patients with liver disease interferes with the intracellular distribution pathway of the lysosomal enzymes and this could contribute to the increased content of lysosomal enzymes present in plasma from these patients. Tunicamycin (0.3-3.0 micrograms/l) increased the percentage of Hex B in the medium, whereas an increased release of Hex was noted only after 48 h. Tunicamycin is known to enhance the secretion of N-linked oligosaccharide-free forms of lysosomal enzymes. Thus the oligosaccharide chains on alpha- and beta-subunits seem to be important for the normal formation process of the Hex A isoenzyme.

Central nervous and systemic kinetics of ramipril and ramiprilat in the conscious dog

The central nervous and systemic kinetics of ramipril, an angiotensin-converting enzyme inhibitor prodrug, and its active metabolite ramiprilat were studied in conscious beagle dogs after sampling of cerebrospinal fluid (CSF) and blood during chronic drug administration. The cardiovascular effect of angiotensin-converting enzyme inhibitors have been suggested to be mediated partly by central action. Ramiprilat and ramipril were determined in CSF and plasma by a gas chromatographic-mass spectrometric assay method. After 10 mg/kg of ramipril, given orally to four dogs once daily for 7 days, significant concentrations of ramiprilat were measured in CSF over the 24-h period after both the 1st and 7th day of treatment. The CSF/plasma (unbound) ratios of ramiprilat on day 7 were (mean +/- S.D.): 0.01 +/- 0.003 (2 h after dose), 0.18 +/- 0.05 (12 h after dose) and 0.32 +/- 0.11 (24 h after dose). Measurable concentrations of ramipril were recorded in plasma after oral dosing (bioavailability approximately 45%), whereas in CSF the prodrug concentration was below the minimal determinable levels in most cases. In a second set of experiments, ramiprilat (3 mg/kg) or ramipril (3 mg/kg) were given i.v. to three dogs once daily for 7 days. Ramipril was rapidly cleared from the plasma, clearance being approximately 140 ml/min/kg and half-life about 0.5 h on day 7. The corresponding values for ramiprilat were 8 ml/min/kg and 0.75 h. The CSF/plasma ratios for ramiprilat were essentially the same after i.v. administration of ramiprilat and ramipril and, furthermore, the ratios did not differ significantly from the ratios observed after oral administration of the prodrug.(ABSTRACT TRUNCATED AT 250 WORDS)

A prospective study of the incidence of deep-vein thrombosis within a defined urban population

In a prospective study all positive phlebographies within the well-defined population of the city of Malmö, Sweden, during 1987 were studied in order to determine the incidence of deep venous thrombosis (DVT). Epidemiological data were analysed for the detection of patient groups at increased risk of DVT. The incidence was found to be equal for both sexes, i.e. 1.6 per 1000 inhabitants a year. Risk factors were found to be in accordance with earlier studies. The median age for men was 66 years, compared to 72 years for women. At diagnosis of DVT, 19% of subjects had a known malignancy and within 1 year 5% (19 cases) developed a new malignancy. Of the men, 29% had postoperative or post-traumatic (fracture) DVT, compared to 46% of the women. Fewer patients with DVT than expected (39%) belonged to blood group 0 (31%) (P less than 0.005). Pulmonary embolism (PE) was clinically suspected in only 5% of cases, and diagnosis was verified scintigraphically in 2% of cases. None of these died of PE, but of 6 patients who were found to have PE at autopsy, four died about 4 weeks after the DVT was diagnosed.

Age dependency of cystathionine beta-synthase activity in human fibroblasts in homocyst(e)inemia and atherosclerotic vascular disease

In order to clarify whether cystathionine beta-synthase (CBS) could differentiate groups of patients with various vascular diagnosis, CBS was studied in cultured human skin fibroblasts from 99 human subjects diagnosed as homozygotes or heterozygotes for CBS deficiency or suffering from atherosclerotic vascular disease or Down's syndrome (prone to less atherosclerosis). In addition, embryonic human skin fibroblasts and controls were analysed for CBS. We found significant group differences but the overlap in the hetero- and homozygotes for CBS deficiency was too extensive to allow any individual diagnosis based on cell culture studies. CBS activity was significantly lower in the atherosclerotic patients as compared to control subjects. The difference was mostly due to much higher CBS activity in the younger controls. Age dependency was markedly emphasized by very high values from embryonic cells. A strong negative correlation was noted for age and CBS activity in control subjects but not in the atherosclerotic patients. The results are important for the discussion of homocysteine in atherosclerosis and point to the importance of donor age on CBS activity in cultured cells. In addition, diagnosis of hetero-homozygosity for CBS activity is not possible on an individual basis by this method. Further studies in cell culture systems are needed to investigate if young patients (less than 45 years old) with atherosclerotic disease could be identified by low CBS activity in fibroblast cultures as indicated by this study.

Quantitative estimation of brain white matter abnormalities in elderly subjects using magnetic resonance imaging

Twenty-five elderly subjects were examined with brain magnetic resonance imaging (MRI). The subjects were divided into two groups: those with Mini-Mental State Examination (MMSE) scores above 25, and those subjects with MMSE scores between 18 and 24. The degree of white matter abnormalities (WMA) (expressed as relative volumes) as well as the presence of cerebrovascular risk factors were evaluated in the two groups. We found that a) subjects with low MMSE scores had significantly larger relative volumes of WMA than the subjects with higher scores, b) a significant correlation (rs = 0.53, p < 0.009) between MMSE scores and the relative volume of WMA was also established, and c) a weak significant correlation (rs = -0.51, p < 0.05) between arterial blood pressure and WMA was found in the subjects with high MMSE scores. Besides these findings no other correlations between the presence of cerebrovascular risk factors and WMA were found in any of the groups.

Isolation of Catharanthus alkaloids by solid-phase extraction and semipreparative HPLC

A combination of moderate-pressure chromatography on C18 sorbent and preparative HPLC is developed for rapid isolation of alkaloids from Catharanthus roseus. The procedure is optimized for vindoline and catharanthine with respective yields of 3 and 2 mg per 1 g of dried leaves of the plant. The methodology is also applied for identification of the above and other alkaloids from cultured plant cells.

Electrochemical detection of indole alkaloids of Catharanthus roseus in high-performance liquid chromatography

Hydrodynamic voltammograms for indole and five indole alkaloids with different amino functions were obtained in order to evaluate the applicability of high-performance liquid chromatography (HPLC) with coulometric detection to these compounds. With the exception of serpentine, which has a quaternary nitrogen in its structure, all the compounds were oxidised and gave net signals of greater than 25 nA pmol(-1) at potentials of between +0.2 and +0.85 V versus a solid Pd electrode in an acetate-buffered (pH 6.5) water-methanol-acetonitrile system. An HPLC assay for quantifying picomole amounts of catharanthine and ajmalicine in Catharanthus roseus cell culture samples is described.

Surface marker characterization of EBV target cells in normal blood and tonsil B lymphocyte populations

Human FACS-sorted B lymphocyte subpopulations were investigated for their susceptibility to immortalization by Epstein Barr virus (EBV). Only B cells reacting with the monoclonal antibody B2 were immortalized, whereas cells reacting with anti-human IgG or the monoclonal antibody BB2 were not responding. Cells positive or negative for IgM, IgD, Burkitt's lymphoma antigen (BLA), BB1, and HB2 were all transformed by EBV.

Surface marker characterization of EBV target cells in normal blood and tonsil B lymphocyte populations

Human FACS-sorted B lymphocyte subpopulations were investigated for their susceptibility to immortalization by Epstein Barr virus (EBV). Only B cells reacting with the monoclonal antibody B2 were immortalized, whereas cells reacting with anti-human IgG or the monoclonal antibody BB2 were not responding. Cells positive or negative for IgM, IgD, Burkitt's lymphoma antigen (BLA), BB1, and HB2 were all transformed by EBV.

Control of replication of FII plasmids: comparison of the basic replicons and of the copB systems of plasmids R100 and R1

The copy numbers of the FII plasmids R1 and R100 were determined in four different ways and found to be identical. Deletion of one of the copy number control genes, copB, together with its promoter gives rise to plasmid copy mutants with an increased copy number. The increase was found to be 8- and 3.5-fold for plasmids R1 and R100, respectively. These deletion derivatives were found to be extremely sensitive to the presence of CopB activity from their own parent plasmid but not to that of the other plasmid. Hence, the CopB protein and its target are plasmid-specific and not FII-group-specific. These results are consistent with the high degree of nonhomology between plasmids R1 and R100 in a 250-bp region covering the distal part of the copB gene and the repA promoter region, which contains the target for the CopB protein.

Isolation and characterization of new copy mutants of plasmid R1, and identification of a polypeptide involved in copy number control

Site-specific deletions and insertions in the replication region of plasmid R1 have generated a new class of copy mutants that are present in the cell with 10-15-fold increased copy number. All mutations described inactivate a copy number control gene which is distinct from another cop inc gene that was identified previously (Molin and Nordström 1980). Insertion of the lac operon lacking the normal lac promoter has been used to determine the direction of transcription of this cop gene. The mutants may all be complemented by wild-type plasmid derivatives and are thus recessive. In incompatibility tests with wild-type R1 plasmids, these mutants are indistinguishable from the wild-type plasmid. It therefore seems that this cop function does not play an important role for the incompatibility function. A polypeptide, molecular weight 11,000, has been identified as being the product of this cop gene.