Biomedical subjects

B Andersson

Publications and source records attributed to B Andersson.

At least 37 records · Page 2Linked to original sources

PubMed2003

Nearly complete genetic maps of Pinus sylvestris L. (Scots pine) constructed by AFLP marker analysis in a full-sib family.

We have constructed nearly complete linkage maps of Pinus sylvestris (L.) using AFLP markers based on a two-way pseudo-testcross strategy in a full-sib family founded in an advanced breeding program. With 39 primer combinations, a total of 737 markers (320 from the mother and 417 from the father) segregated in a 1:1 ratio, corresponding to DNA polymorphism: heterozygous in one parent and null in the other. In the maternal parent, 188 framework markers were mapped in 12 linkage groups, equivalent to the Pinus haploid chromosome number, with a total coverage of 1,695.5 cM. In the paternal parent, 245 framework markers established a map with 15 linkage groups, spanning a genome length of 1,718.5 cM. The estimated total map length was L(F) = 1,681 cM for the female and L(M) = 1,645 cM for the male using a modified method-of-moment estimator. Combining these values with those estimated from the observed map lengths in both parents, we estimated the genome length in Scots pine to be between 1,600 and 2,100 cM. Our genome coverage was estimated to be more than 98% with a framework marker interval of 20 cM for both parents. Most of the female and male linkage groups were associated through the analysis of the intercross markers.

Chromosome Mapping↗

PubMed2003

Increased exercise ejection fraction and reversed remodeling after long-term treatment with metoprolol in congestive heart failure: a randomized, stratified, double-blind, placebo-controlled trial in mild to moderate heart failure due to ischemic or idiopathic dilated cardiomyopathy.

BACKGROUND: the effects of long-term administration of beta-blockers on left ventricular (LV) function during exercise in patients with ischemic heart disease (IHD) and idiopathic dilated cardiomyopathy (DCM) are controversial. PATIENTS AND METHODS: patients with stable congestive heart failure (CHF) (New York heart association [NYHA] class II and III) and ejection fraction (EF) < or =0.40 were randomized to metoprolol, 50 mg t.i.d. or placebo for 6 months. Patients were divided into two groups: ischemic heart disease (IHD) and idiopathic dilated cardiomyopathy (DCM). The mean EF was 0.29 in both groups and 92% were taking angiotensin-converting enzyme (ACE) inhibitors. In the IHD group, 84% had suffered a myocardial infarction (MI) and 64% had undergone revascularization at least 6 months before the study. LV volumes were measured by equilibrium radionuclide angiography. Mitral regurgitation was assessed by Doppler echocardiography. All values are changes for metoprolol subtracted by changes for placebo. RESULTS: metoprolol improved LV function markedly both at rest and during sub-maximal exercise in both groups. The mean increase in EF was 0.069 at rest (P<0.001) and 0.078 during submaximal exercise (P<0.001). LV end-diastolic volume decreased by 22 ml at rest (P=0.006) and by 15 ml during exercise (P=0.006). LV end-systolic volume decreased by 23 ml both at rest (P=0.001) and during exercise (P=0.004). Exercise time increased by 39 s (P=0.08). In the metoprolol group, mitral regurgitation decreased (P=0.0026) and only one patient developed atrial fibrillation vs. eight in the placebo group (P=0.01). CONCLUSION: metoprolol improves EF both at rest and during submaximal exercise and prevents LV dilatation in mild to moderate CHF due to IHD or DCM.

Adrenergic beta-Antagonists↗

PubMed2003

Drying of linseed oil paints: the effects of substrate on the emission of aldehydes.

The effect of substrate on the emission of aldehydes from linseed oil paint was investigated. Plates of glass, fiberboard, gypsum board, lime mortar and wood lath were painted, and then placed into emission chambers. Samples were collected every eighth hour over 10 days with 2,4-dinitrophenylhydrazin samplers. Analysis was performed with liquid chromatography/UV-detection and mass spectrometry. Paint applied on gypsum board gave the highest total amount of emitted carbonyls, and that on wood lath gave the least. Painted glass had the highest contribution of unsaturated species, and lime mortar, the lowest. Lime mortar also had the highest momentary levels of a single species, 443 nmol/h/m2 of propanal, while fiberboard peaked at only 123 nmol/h/m2 of propanal. In turn, the emission from the painted fiberboard had the slowest decline, and thus at the end of the experiment the highest levels. All substrates gave an emission that peaked within 16 h.

Air Pollution, Indoor↗

PubMed2003

A kinetic study in adults with food hypersensitivity assessed as eosinophil activation in fecal samples.

BACKGROUND: Immune-mediated food hypersensitivity affecting the gut is difficult to evaluate, and objective tools to diagnose local gastrointestinal (GI) inflammatory reactions are lacking. OBJECTIVES: To determine whether allergic manifestations in adults with a history of food-related GI symptoms could be assessed in feces during symptomatic and non-symptomatic periods, using the surrogate markers, eosinophil cationic protein (ECP), eosinophil protein X (EPX) and myeloperoxidase (MPO). METHODS: Thirteen subjects with food hypersensitivity-related GI symptoms, confirmed by a positive double-blind placebo-controlled food challenge (DBPCFC), were subjected to an open kinetic food challenge design for 6 weeks. Symptoms were recorded and scored during the 3-week study period and stool samples were obtained every day. The surrogate markers ECP, EPX and MPO were measured in the supernatants from feces samples. RESULTS: A significant increase in abdominal pain, distension and flatulence was observed during challenge, with a gradual decrease during elimination diet. Both between days and subjects, EPX levels were more frequently increased compared to ECP and MPO. Individuals with a history of a short duration of symptoms had significantly higher mean levels of EPX and MPO than those with a longer duration of symptoms. CONCLUSIONS: An overall increase in levels of eosinophil markers, in particular EPX, was observed in feces from patients with food-related GI symptoms. However, rather than being a tool to differentiate symptomatic from non-symptomatic periods, EPX might be used for detecting an ongoing clinical or subclinical chronic inflammation, that may have an impact on the patient's clinical course of GI symptoms.

Adult↗

PubMed2003

Long-term results favor allogeneic over autologous hematopoietic stem cell transplantation in patients with refractory or recurrent indolent non-Hodgkin's lymphoma.

BACKGROUND: The aim of this study was to compare the outcomes of high-dose therapy (HDT) and allogeneic versus autologous hematopoietic stem cell transplantation (SCT) in patients with refractory or recurrent indolent non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: From January 1991 to March 2000, 112 patients underwent HDT followed by either autologous (68 patients) or allogeneic (44 patients) SCT for refractory or recurrent indolent NHL. Prior conventional chemotherapy had failed in all patients. RESULTS: The two groups were similar with respect to age at transplantation, gender, histological subtypes, number of chemotherapy regimens received before transplantation and International Prognostic Index scores. The median time from diagnosis to transplantation was longer in the autologous than in the allogeneic SCT group (46 versus 27 months, P = 0.002). In the allogeneic SCT group the median follow-up time was 53 months (range 21-113), and the overall survival (OS) and disease-free survival (DFS) rates were 49% and 45%, respectively. After a median follow-up time of 71 months (range 22-109), in the autologous SCT group, the OS and DFS rates were 34% and 17%, respectively. Patients who underwent autologous SCT were more likely to have chemosensitive disease (P <0.001) and were more likely to be in complete remission at the time of transplantation (P = 0.001) than those who underwent allogeneic SCT. However, the probability of disease progression was significantly higher in the autologous SCT group than in the allogeneic SCT group (74% versus 19%, P = 0.003). CONCLUSIONS: Patients who undergo HDT with allogeneic SCT for refractory or recurrent indolent NHL have lower relapse rates but higher treatment-related mortality rates than patients who undergo autologous SCT. However, with the development of non-myeloablative preparative regimens, which can decrease treatment-related mortality, patients with recurrent indolent NHL should be considered for controlled trials of allogeneic transplantation if they have a human leukocyte antigen-identical donor.

Adult↗

PubMed2003

Different responses to dobutamine in the presence of carvedilol or metoprolol in patients with chronic heart failure.

OBJECTIVE: To determine whether patients with congestive heart failure on different beta adrenoreceptor blocking drugs have similar haemodynamic responses to dobutamine. DESIGN: Single centre, single blind, randomised, two period crossover study comparing carvedilol with metoprolol CR/XL. PATIENTS: Ten patients with stable chronic congestive heart failure (ejection fraction < 40%) on chronic treatment with metoprolol CR/XL. METHODS: Patients were treated with carvedilol or metoprolol CR/XL (target dose 50 mg twice daily and 200 mg once daily, respectively) for eight weeks. Stress echocardiography was undertaken at the end of each maintenance period, using dobutamine 5 and 15 microg/kg/min. RESULTS: No significant haemodynamic differences were seen at rest on the two treatments. There was a more pronounced increase in heart rate and cardiac output during dobutamine infusion when the patients were on metoprolol than when they were on carvedilol. Mean arterial pressure increased significantly when the patients were on carvedilol, and cardiac output increased during low dose dobutamine, without further change during high dose dobutamine. During the dobutamine infusion, there was no significant difference in ejection fraction between carvedilol and metoprolol treatment. CONCLUSIONS: Patients with congestive heart failure on a non-selective beta adrenoreceptor blocker or beta1 selective blocker responded differently to the inotropic drug dobutamine: the beta1 blockade caused by metoprolol could be counteracted by dobutamine, whereas with carvedilol a low dose of dobutamine increased cardiac output, and a higher dose of dobutamine caused a pressor effect. These findings may be clinically relevant when choosing an inotropic drug.

Adrenergic beta-Antagonists↗

PubMed2003

Perspectives on hepatitis B infections and the efficacy of vaccination (hepatitis B and pneumococci) in dialysis patients.

Hepatitis B is a well known problem in dialysis units. We therefore examined the historical frequency of hepatitis B carriers in our unit, our vaccination program to hepatitis B virus (HBV), the response to hepatitis B vaccine, the IgG subclass response of anti-HBs and the response and IgG subclass response to pneumococcal vaccination (another vaccine) in dialysis patients. From 1970 and onwards 23 HBV carriers were found, but no new cases of hepatitis B occurred during the study period, i.e. from 1980 and onwards. Only one of the carriers was alive by the end of 2001. In four patients liver disease (in one of them liver cirrhosis) may have been a concomitant cause of death. The antibody response to hepatitis B vaccine was significantly lower in patients than in staff. In four patients a fourth injection was cancelled due to transplantation and bad health, while such data were lacking in 8 cases. In anti-HBs positive patients and controls a significant difference in the response of healthy adults was observed in anti-HBs IgG1 (p < 0.001) vs all other IgG subclasses. Dialysis patients had low levels, or negative findings, in all cases, with IgG1 as the highest proportion found (3/11 patients). An antibody response to pneumococcal vaccination was registered in 25 out of 29 dialysis patients (in all 86%). The IgG-subclass vaccination response to pneumococci in 28 dialysis patients was mainly IgG2 and IgG1 but also occurred in IgG3 and IgG4. Prevaccination antibody levels of the controls were higher in IgG1 and IgG2 (p < 0.01) (n = 21) than in dialysis patients (n = 28). Hepatitis B is nowadays a rare, but still dangerous disease in nephrology units. Dialysis patients have a reduced response to hepatitis B vaccine and vaccination schedules should be started early as some patients otherwise may not receive a fourth injection. The adequate antibody response to pneumococcal vaccination mainly due to IgG2 and IgG1 antibodies indicates that the antigen involved is important in vaccination responses in dialysis patients.

Case-Control Studies↗

PubMed2003

Sustainability concept for a newly built urban area in Malmö, Sweden.

National goals regarding sustainable development from the Swedish government were decisive in the planning process when the newly built city district Western Harbour was established in the city of Malmö, Sweden. A systems analysis was used as a tool for evaluating different collection and treatment systems. This type of analysis does not include more subjective factors such as acceptance of organic fertilizers based on human waste and user acceptance of collection schemes. These aspects, however, will often determine the success of a technical solution. When the system for collection and treatment of old organic waste and wastewater was designed, both subjective and objective factors were considered. This meant that a centralised solution for wastewater treatment was selected. In order to facilitate a more sustainable solution for sludge management a treatment process with recovery of phosphorus will have to be introduced. Organic waste is sorted out and treated in an anaerobic digestion process. Source sorting of solid organic waste has been difficult to implement in Sweden due to inadequate sorting discipline. As a consequence two relatively new systems are tested in the area. A comprehensive evaluation will be carried out during a period of two years.

Cities↗

PubMed2003

Upgrading the Sjölunda WWTP according to a novel process concept.

The Sjölunda wastewater treatment plant in Malmö, Sweden, was upgraded for extended nutrient removal in 1998-1999. The design was based on future effluent standards of 10 mg BOD7/l, 0.3 mg total-P/l and 8 mg total-N/l. The upgrading concept took into consideration existing processes and structures, resulting in a cost-effective and compact upgrading. To introduce nitrification, the existing trickling filters for BOD-removal were converted to a nitrifying mode. A sequencing batch reactor for nitrification of supernatant was necessary to control the ammonia load. Denitrification was accomplished in a moving bed biofilm reactor with addition of external carbon source. The future effluent standards could be met by the upgraded plant. The trickling filters were stable despite varying loading conditions. High rates and low effluent ammonia concentrations were achieved. Essential features for stable post denitrification were control strategies for carbon source dosage and avoiding phosphorus limitation.

Bioreactors↗

PubMed2002

Asthma and allergies at school--a Swedish national position paper.

The marked rise in allergies during the past decade has been increasingly perceptible for school personnel. A quarter of Swedish parents of children with allergies are unsatisfied with the school environment and how the schools are organized around their children. The Association of School Physicians has, together with six other medical, teaching and patient organizations, developed written guidelines for the management of asthma and allergies in Swedish schools. The aim was to regulate the responsibility of the school and its personnel for students with asthma and allergies, and to strengthen safety arrangements within schools. A secondary aim was to describe how the curriculum, teaching equipment, excursions, and other school activities, could be arranged appropriately and safely for students with asthma and allergies. Five-hundred copies of the document were circulated to all of Sweden's municipalities, county councils and pediatric departments. There was general agreement regarding the schools' responsibility that no child should risk becoming ill or having exacerbation of symptoms due to conditions at school. Recommendations regarding smoking on school premises and the use of perfumes were criticised. The strength of this document is that all organizations actively involved with schools have agreed upon these recommendations. This document serves to suggest a minimum level of activities thus ensuring that even students with asthma and allergies will receive appropriate schooling.

Asthma↗

PubMed2002

Myocardial ischemia induces coronary t-PA release in the pig.

BACKGROUND: Tissue-type plasminogen activator (t-PA) is the key factor in initiating endogenous fibrinolysis in the vascular compartment. Regulated release of t-PA from endothelial stores is rapidly induced by several humoral factors as well as coagulation activation products. The aim of the present study was to test the hypothesis that regional myocardial ischemia induces regulated release of t-PA in the coronary vasculature in vivo. METHODS: Healthy anesthetized (pentobarbital) pigs (n=8) were studied before and after a 10-min left anterior descending region coronary artery occlusion (LAD). Coronary fluxes of lactate, total t-PA antigen (ELISA, detecting both complex bound and free fraction) and active t-PA (functional assay detecting biological free fraction) were determined at 1, 3, 5 and 10 min of reflow. RESULTS: Coronary occlusion induced myocardial lactate production in all animals. Net coronary release of total t-PA, which was 21 ng/min during control, increased rapidly during reflow with a peak after only 1 min (136 ng/min), and returned to baseline within 3 min. Net release of active t-PA mirrored the overall net release response, but fell short of statistical significance. CONCLUSION: Data indicate a local myocardial profibrinolytic response following regional ischemia, which may serve as a prompt defence against coronary thromboembolic events.

Animals↗

PubMed2002

Response of in vivo protein synthesis in T lymphocytes and leucocytes to an endotoxin challenge in healthy volunteers.

In vivo determination of protein synthesis in immune cells reflects metabolic activity and immunological activation. An intravenous injection of endotoxin to healthy volunteers was used as a human sepsis model, and in vivo protein synthesis of T lymphocytes and leucocytes was measured. The results were related to plasma concentrations of selected cytokines, peripheral cell counts and subpopulations of immune cells. The subjects (n = 8 + 8) were randomized to an endotoxin (4 ng/kg) or a saline group. In vivo protein synthesis was determined twice: before and 1-2.5 h after the endotoxin/saline injection. Protein synthesis decreased in isolated T lymphocytes, but increased in leucocytes. Plasma levels of TNF-alpha, IL-8, IL-6, IL-1 ra and IL-10 were elevated, whereas IL-2 and IFN-gamma, produced predominantly by T lymphocytes, did not change in response to endotoxin. Neutrophils increased, whereas lymphocytes and monocytes decreased 2.5 h after the endotoxin injection. Flow cytometry revealed a drop in total CD3+ T lymphocytes and CD56+ natural killer cells, accompanied by an increase in CD15+ granulocytes. In summary, in vivo protein synthesis decreased in T lymphocytes, while the total leucocyte population showed a concomitant increase immediately after the endotoxin challenge. The changes in protein synthesis were accompanied by alterations in immune cell subpopulations and in plasma cytokine levels.

Adult↗

PubMed2002

Risk of therapy-related myelodysplastic syndrome/acute leukemia following high-dose therapy and autologous bone marrow transplantation for non-Hodgkin's lymphoma.

BACKGROUND: Several recent reports have suggested that patients with non-Hodgkin's lymphomas (NHL) who undergo autologous stem cell transplantation (ASCT) are at increased risk of developing therapy-related myelodysplastic syndrome (tMDS) and acute myelogenous leukemia (tAML). PATIENTS AND METHODS: We analyzed 493 patients with NHL who underwent ASCT at The University of Texas M.D. Anderson Cancer Center between January 1990 and August 1999. RESULTS: With a median follow-up time of 21 months after HDT, 22 patients developed persistent cytopenia in at least one cell line with morphologic or cytogenetic evidence of tMDS or tAML. Univariate analysis identified prior fludarabine therapy, bone marrow involvement with lymphoma, and total body irradiation (TBI) as significant risk factors for the development of tMDS/tAML (P <0.05). Multiple logistic regression analysis showed that TBI was independently associated with an increased risk of developing tMDS/tAML (P <0.01). Further analysis of the patients who received TBI revealed that patients receiving TBI in combination with cyclophosphamide and etoposide were more likely to develop tMDS/tAML than those who received TBI with cyclophosphamide or thiotepa (P <0.01). The median survival of patients developing tMDS/tAML was 7.5 months (range 0-32 months). CONCLUSIONS: TBI, especially when used in combination with cyclophosphamide and etoposide as the pretransplant conditioning regimen, is a significant risk factor for the development of tMDS/tAML.

Acute Disease↗

PubMed2002

Longitudinal myocardial contraction improves early during titration with metoprolol CR/XL in patients with heart failure.

OBJECTIVE: To investigate diastolic and systolic left ventricular recovery during titration with metoprolol CR/XL (controlled release/extended release). DESIGN: Placebo run in, followed by an open study. SETTING: University hospital. PATIENTS: 14 patients with chronic heart failure. INTERVENTIONS: Metoprolol CR/XL titrated from 12.5 mg once daily to 200 mg once daily. MAIN OUTCOME MEASURES: M mode recordings of atrioventricular (AV) plane displacement, Doppler measurement of transmitral flow and pulmonary venous flow, two dimensional ejection fraction, and measurement of venous plasma concentration of noradrenaline. Patients were investigated after 2, 4, 6, and 24 weeks of treatment. RESULTS: A reduction of heart rate was observed on the first dose (12.5 mg once daily), from a mean (SD) of 74 (11) to 67 (11) beats/min, p < 0.05. This was accompanied by prominent effects on AV plane filling parameters, including an increase in early diastolic filling period from 87 (28) to 105 (33) ms (p < 0.05), and in the lateral AV plane fractional shortening from 8.7 (2.7)% to 10.2 (2.8)% (p < 0.05). An early trend towards improvement in global systolic left ventricular function was also seen, although this was not significant until six weeks. Ejection fraction increased from 33 (7.5)% to 38 (11)% (p < 0.05). CONCLUSIONS: First effects of left ventricular recovery during beta blocker treatment were seen in recordings of longitudinal performance, as expressed by AV plane displacement. Doppler flow dynamics as well as global systolic recovery appeared several weeks later, emphasising the importance of longitudinal performance in evaluating left ventricular function.

Adrenergic beta-Antagonists↗

PubMed2001

The initial steps of biogenesis of cyanobacterial photosystems occur in plasma membranes.

During oxygenic photosynthesis in cyanobacteria and chloroplasts of plants and eukaryotic algae, conversion of light energy to biologically useful chemical energy occurs in the specialized thylakoid membranes. Light-induced charge separation at the reaction centers of photosystems I and II, two multisubunit pigment-protein complexes in the thylakoid membranes, energetically drive sequential photosynthetic electron transfer reactions in this membrane system. In general, in the prokaryotic cyanobacterial cells, the thylakoid membrane is distinctly different from the plasma membrane. We have recently developed a two-dimensional separation procedure to purify thylakoid and plasma membranes from the genetically widely studied cyanobacterium Synechocystis sp. PCC 6803. Immunoblotting analysis demonstrated that the purified plasma membrane contained a number of protein components closely associated with the reaction centers of both photosystems. Moreover, these proteins were assembled in the plasma membrane as chlorophyll-containing multiprotein complexes, as evidenced from nondenaturing green gel and low-temperature fluorescence spectroscopy data. Furthermore, electron paramagnetic resonance spectroscopic analysis showed that in the partially assembled photosystem I core complex in the plasma membrane, the P700 reaction center was capable of undergoing light-induced charge separation. Based on these data, we propose that the plasma membrane, and not the thylakoid membrane, is the site for a number of the early steps of biogenesis of the photosynthetic reaction center complexes in these cyanobacterial cells.

Cell Membrane↗

PubMed2001

Impact of high-dose chemotherapy on peripheral T-cell lymphomas.

PURPOSE: To evaluate the outcome of high-dose chemotherapy (HDCT) and autologous or allogeneic hematopoietic transplantation in patients with peripheral T-cell lymphoma (PTCL) who experienced disease recurrence after prior conventional chemotherapy. PATIENTS AND METHODS: We performed a retrospective analysis of 36 PTCL patients from the University of Texas M.D. Anderson Cancer Center treated between 1989 and 1998 with HDCT and autologous or allogeneic hematopoietic transplantation. RESULTS: A total of 36 patients were studied (29 received autologous transplantation, and seven received allogeneic transplantation). The overall survival rate at 3 years was 36% (95% confidence interval [CI], 23% to 59%), and the progression-free survival (PFS) rate was 28% (95% CI, 16% to 49%). The pretransplant serum lactate dehydrogenase level was the most important prognostic factor for both survival and PFS rates (P < .001). A Pretransplant International Prognostic Index score of < or = 1 indicated a superior survival rate (P = .036) but not an improved PFS rate. A median follow-up of 43 months (range, 13 to 126 months) showed 13 patients (36%) were still alive with no evidence of disease. CONCLUSION: Our results are comparable to the published data on HDCT in B-cell non-Hodgkin's lymphoma (NHL) patients despite the fact that patients with PTCL are known to have a worse outcome compared with B-cell NHL patients. Considering the dismal outcome of conventional chemotherapy in PTCL patients, these data suggest the hypothesis that the poor prognostic implication of T-cell phenotyping in NHL might be overcome by frontline HDCT and transplantation.

Adult↗

PubMed2001

Ozone removal in the sampling of parts per billion levels of terpenoid compounds: an evaluation of different scrubber materials.

Some reactive volatile organic compounds (VOCs) are prone to degradation during sampling in an ozone-rich environment. A wide variety of different chemicals have been used to remove the ozone prior to sampling, but the possibility of interference by such chemicals with the sampled VOCs has not been thoroughly examined. In the present investigation, the retention/degradation of four terpenes (alpha-pinene, beta-pinene, 3-carene, and limonene) and isoprene together with some of their oxidation products (alpha-pinene oxide, nopinone, 4-acetyl-1-methylcyclohexene (AMCH), methylglyoxal, and methacrolein) has been studied, using various ozone-removing chemicals in an attempt to evaluate their potential as ozone scrubbers in the sampling of ambient air. The chemicals included in this first screening and their ozone-removing capacity are as follows: KI, MnO2, and Na2SO3 removed ozone for more than 24 h when exposed to 73-78 ppb (150-160 microg/m3) at a sampling flow rate of 500 mL/min. Silanized poly(1,4-phenylene sulfide) (PFS) removed ozone for 5 h, unsilanized PFS removed ozone for 1 h and 50 min, and Na2S2O3 removed ozone for 20 min. The recovery of the selected compounds with the different scrubbers was >95% for all compounds for KI; >95% for the terpenes oxidation products; >90% for the terpenes and isoprene for PFS; >90% for the terpenes and isoprene for MnO2 on copper nets, Na2SO3, and Na2S2O3; and <90% for the terpenes and isoprene for carulite (a commercial mixture between MnO2, CuO, and Al2O3), CuO, and indigo carmine.

Air Pollutants↗

PubMed2001

A chloroplast DegP2 protease performs the primary cleavage of the photodamaged D1 protein in plant photosystem II.

Although light is the ultimate substrate in photosynthesis, it can also be harmful and lead to oxidative damage of the photosynthetic apparatus. The main target for light stress is the central oxygen-evolving photosystem II (PSII) and its D1 reaction centre protein. Degradation of the damaged D1 protein and its rapid replacement by a de novo synthesized copy represent the important repair mechanism of PSII crucial for plant survival under light stress conditions. Here we report the isolation of a single-copy nuclear gene from Arabidopsis thaliana, encoding a protease that performs GTP-dependent primary cleavage of the photodamaged D1 protein and hence catalysing the key step in the repair cycle in plants. This protease, designated DegP2, is a homologue of the prokaryotic Deg/Htr family of serine endopeptidases and is associated with the stromal side of the non-appressed region of the thylakoid membranes. Increased expression of DegP2 under high salt, desiccation and light stress conditions was measured at the protein level.

Amino Acid Sequence↗