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1.
Article in English | MEDLINE | ID: mdl-37660218

ABSTRACT

BACKGROUND: This study aimed to evaluate the histopathological concordance rates between prostate biopsies and radical prostatectomy specimens according to the applied biopsy approach (transrectal or transperineal). METHODS: We studied patients who had been newly diagnosed with clinically significant prostate cancer and who underwent a radical prostatectomy between 2018 and 2022. Patients were included if they underwent a prebiopsy magnetic resonance imaging and if they had not been previously treated for prostate cancer. Histopathological grading on prostate biopsies was compared with that on radical prostatectomy specimens. Univariable and multivariable logistic regression analyses were performed to assess the effect of the applied biopsy approach on histopathological concordance. Additional analyses were performed to assess the effect of the applied biopsy approach on American Urological Association risk group migration, defined as any change in risk group after radical prostatectomy. RESULTS: In total, 1058 men were studied, of whom 49.3% (522/1058) and 50.7% (536/1058) underwent transrectal and transperineal prostate biopsies, respectively. Histopathological disconcordance was observed in 37.8% (400/1058) of men while American Urological Association risk group migration was observed in 30.2% (320/1058) of men. A transperineal biopsy approach was found to be independently associated with higher histopathological concordance rates (OR 1.33 [95% CI 1.01-1.75], p = 0.04) and less American Urological Association risk group migration (OR 0.70 [95% CI 0.52-0.93], p = 0.01). CONCLUSIONS: The use of a transperineal biopsy approach improved histopathological concordance rates compared to the use of a transrectal biopsy approach. A transperineal biopsy approach may provide more accurate risk stratification for clinical decision-making. Despite recent improvements, histopathologic concordance remains suboptimal and should be considered before initiating management.

2.
Urol Oncol ; 40(2): 58.e1-58.e7, 2022 02.
Article in English | MEDLINE | ID: mdl-34404590

ABSTRACT

PURPOSE: To assess the diagnostic performance of prostate specific membranous antigen (PSMA) positron emission tomography/computed tomography (PET/CT) imaging to localize primary prostate cancer (PCa) in men with persistent elevated prostate-specific antigen (PSA) levels and previous prostate biopsies that were negative for PCa. METHODS: In this study, 34 men with persistently elevated PSA-levels, previous negative for PCa biopsies and who subsequently underwent diagnostic PSMA-PET/CT imaging were retrospectively evaluated. Men were divided into 3 groups: 1. 12 men with a previous negative mpMRI scan (PI-RADS 1-2) 2. 17 men with a positive mpMRI scan (PI-RADS 3-5), but negative MRI-targeted biopsies and 3. Four men in whom mpMRI was contraindicated. If PSMA-avid lesions were seen, patients underwent 2-4 cognitive targeted biopsies in combination with systematic biopsies. The detection rate of PSMA-PET/CT for PCa, and the accuracy of (possible) targeted biopsies were calculated. RESULTS: Included men had a median PSA-level of 22.8 ng/mL (Interquartile Range 15.6-30.0) at the time of PSMA-PET/CT. Elevated PSMA-ligand uptake in the prostate suspicious for PCa was observed in 22/34 patients (64.7%). In 18/22 patients (54.5%), PSMA-targeted prostate biopsies were performed. In 3/18 patients (16.6%), the targeted biopsies showed International Society of Urological Pathology (ISUP) score 1-2 PCa. The other men had inflammation or benign findings after histopathological examination of the biopsy cores. CONCLUSION: In this study, the clinical value of PSMA-PET/CT for patients with an elevated PSA-level, and negative for PCa biopsies was low. Only very few men were diagnosed with PCa, and no clinically significant PCa was found.


Subject(s)
Biopsy/methods , Positron Emission Tomography Computed Tomography/methods , Prostate-Specific Antigen/analysis , Prostate/pathology , Humans , Male , Surveys and Questionnaires
3.
J Robot Surg ; 16(2): 453-462, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34120255

ABSTRACT

The objective is to evaluate the effect of robot-assisted radical prostatectomy (RARP)-related postoperative complications on the 6-month postoperative health-related quality of life (HRQoL). A total of 1008 patients underwent a RARP with or without pelvic lymph node dissection (PLND) between 2012 and 2020 and were invited to complete questionnaires about HRQoL and functional outcomes (urinary incontinence (UI), erectile dysfunction (ED) and urinary complaints (UC)) before and 6 months after RARP. Patient characteristics and postoperative complications up to 90 days after surgery were prospectively recorded. Associations between complications and HRQoL/functional outcomes were assessed by multivariate linear regression analyses. In total, 528 patients (52.4%) were included in the analyses. Complications occurred in 165/528 (31.3%) patients, of which 30/165 (18.2%) had a Clavien-Dindo ≥ III complication. In multivariate regression analyses, postoperative complications were not significantly associated with postoperative HRQoL, UI and ED (p = 0.73, p = 0.72 and p = 0.95, respectively), but were significantly associated with a minor increase in UC (ß = 1.7, p < 0.001). More specifically, infectious and urological complications were significantly associated with an increase in UC (ß = 1.9, p < 0.001 and ß = 0.9, p = 0.004, respectively). The presence of UTI, in particular, was significantly associated with this minor increase (ß = 1.5, p = 0.002). Functional outcomes were all significantly associated with the HRQoL at 6 months postoperatively. No significant associations were found between postoperative complications and HRQoL at 6 months after RARP. However, worse functional outcomes were associated with a worse HRQoL at 6 months postoperatively. In addition, postoperative infectious and urological complications were significantly associated with a minor increase in UC.


Subject(s)
Robotic Surgical Procedures , Robotics , Urinary Incontinence , Humans , Male , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Prostatectomy/adverse effects , Quality of Life , Robotic Surgical Procedures/methods , Treatment Outcome , Urinary Incontinence/epidemiology , Urinary Incontinence/etiology
5.
World J Urol ; 38(9): 2197-2205, 2020 Sep.
Article in English | MEDLINE | ID: mdl-31728672

ABSTRACT

BACKGROUND: Radical cystectomy (RC) is associated with substantial postoperative mortality. In this study, we analyzed early (30-day; 30 M) and late (30-90-day; 30-90 M) mortality after RC in a Dutch tertiary referral center and determined factors associated with 30 M, 30-90 M and 90-day mortality (90 M). PATIENTS AND METHODS: We identified 823 patients who underwent RC for bladder cancer in the Netherlands Cancer Institute between 1997 and 2017. Predictive factors for mortality were analyzed to identify patients with a higher mortality risk. Multivariate logistic regression analysis was performed to examine the influence of patient, surgical and histopathological variables on 30 M, 30-90 M and 90 M. RESULTS: Thirty-day mortality was 1.9% and 90 M was 6.0%. Multivariable analysis showed that age (OR 1.08, 95% CI 1.01-1.1, p = 0.002) and ASA 3-4 (OR 3.57, 95% CI 1.25-10.16, p = 0.002) were significant predictors of 30 M while higher ASA score (OR 2.9, 95% CI 1.31-6.5, p = 0.009) and higher pathological T stage (OR 8.8, 95% CI 1.9-40.4, p = 0.005) were associated with 30-90 M. Risk of 90 M was increased in patients with ASA 3-4 (OR 2.4, 95% CI 1.2-4.9, p = 0.01), pT3-4 (OR 3.1, 95% CI 1.27-7.57, p = 0.01) and positive LNs (OR 2.5, 95% CI 1.25-4.98, p = 0.009). CONCLUSIONS: Patient-related factors predicted 30 M whereas both patient-related and cancer-related factors predicted 30-90 M. This suggests that patient mix, i.e. patient- vs. cancer-related factors for 30 M and 30-90 M, should be taken into account if mortality rates are to be compared between hospitals.


Subject(s)
Cystectomy , Urinary Bladder Neoplasms/mortality , Urinary Bladder Neoplasms/surgery , Aged , Aged, 80 and over , Cancer Care Facilities , Cystectomy/methods , Female , Humans , Male , Middle Aged , Prognosis , Retrospective Studies , Time Factors
6.
J Urol ; 201(6): 1142, 2019 06.
Article in English | MEDLINE | ID: mdl-30870068
7.
Contemp Clin Trials Commun ; 9: 121-129, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29696234

ABSTRACT

BACKGROUND: Following radical nephro-ureterectomy for urothelial carcinoma of the upper urinary tract (UUT), the reported bladder recurrence rate of urothelial carcinoma is 22-47%. A single intravesical instillation of chemotherapy within 10 days following nephro-ureterectomy has the potential to decrease the risk of a bladder recurrence significantly. Despite recommendation by the European Association of Urology guideline to administer a single instillation postoperatively, the compliance rate is low because the risk of extravasation of chemotherapy. AIM: To reduce the risk of bladder cancer recurrence by a single intravesical instillation of Mitomycin immediately (within 3 h) before radical nephro-ureterectomy or partial ureterectomy. METHODS: Adult patients (age ≥ 18 years) with a (suspicion of a) urothelial carcinoma of the UUT undergoing radical nephro-ureterectomy or partial ureterectomy will be eligible and will receive a single intravesical instillation of Mitomycin within 3 h before surgery. In total, 170 patients will be included in this prospective, observational study. Follow-up will be according to current guidelines. RESULTS: The primary endpoint is the bladder cancer recurrence rate up to two years after surgery. Secondary endpoints are: a) the compliance rate; b) oncological outcome; c) possible side-effects; d) the quality of life; e) the calculation of costs of a single neoadjuvant instillation with Mitomycin and f) molecular characterization of UUT tumors and intravesical recurrences. CONCLUSIONS: A single intravesical instillation of Mitomycin before radical nephro-ureterectomy or partial ureterectomy may reduce the risk of a bladder recurrence in patients treated for UUT urothelial carcinoma and will circumvent the disadvantages of current therapy.

8.
J Urol ; 195(5): 1428-1435, 2016 May.
Article in English | MEDLINE | ID: mdl-26529298

ABSTRACT

PURPOSE: We assess the accuracy of multiparametric magnetic resonance imaging for significant prostate cancer detection before diagnostic biopsy in men with an abnormal prostate specific antigen/digital rectal examination. MATERIALS AND METHODS: A total of 388 men underwent multiparametric magnetic resonance imaging, including T2-weighted, diffusion weighted and dynamic contrast enhanced imaging before biopsy. Two radiologists used PI-RADS to allocate a score of 1 to 5 for suspicion of significant prostate cancer (Gleason 7 with more than 5% grade 4). PI-RADS 3 to 5 was considered positive. Transperineal template guided mapping biopsy of 18 regions (median 30 cores) was performed with additional manually directed cores from magnetic resonance imaging positive regions. The anatomical location, size and grade of individual cancer areas in the biopsy regions (18) as the primary outcome and in prostatectomy specimens (117) as the secondary outcome were correlated to the magnetic resonance imaging positive regions. RESULTS: Of the 388 men who were enrolled in the study 344 were analyzed. Multiparametric magnetic resonance imaging was positive in 77.0% of patients, 62.5% had prostate cancer and 41.6% had significant prostate cancer. The detection of significant prostate cancer by multiparametric magnetic resonance imaging had a sensitivity of 96%, specificity of 36%, negative predictive value of 92% and positive predictive value of 52%. Adding PI-RADS to the multivariate model, including prostate specific antigen, digital rectal examination, prostate volume and age, improved the AUC from 0.776 to 0.879 (p <0.001). Anatomical concordance analysis showed a low mismatch between the magnetic resonance imaging positive regions and biopsy positive regions (4 [2.9%]), and the significant prostate cancer area in the radical prostatectomy specimen (3 [3.3%]). CONCLUSIONS: In men with an abnormal prostate specific antigen/digital rectal examination, multiparametric magnetic resonance imaging detected significant prostate cancer with an excellent negative predictive value and moderate positive predictive value. The use of multiparametric magnetic resonance imaging to diagnose significant prostate cancer may result in a substantial number of unnecessary biopsies while missing a minimum of significant prostate cancers.


Subject(s)
Image-Guided Biopsy/methods , Magnetic Resonance Imaging/methods , Neoplasm Staging , Prostate/pathology , Prostatic Neoplasms/diagnosis , Aged , Humans , Male , Middle Aged , Prospective Studies , ROC Curve , Retrospective Studies
9.
Prostate Cancer Prostatic Dis ; 19(1): 46-52, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26458959

ABSTRACT

BACKGROUND: Current data on the use of irreversible electroporation (IRE) in the treatment of prostate cancer (PCa) is limited. We aim to evaluate the safety, short-term functional and oncological outcomes of focal IRE in low-intermediate risk PCa. METHODS: Between February 2013 and May 2014, 32 consecutive men underwent IRE at a single centre. Patients with low-intermediate risk PCa who had not received previous PCa treatment were included for analysis. The tumour was ablated using 3-6 electrodes, ensuring a minimum 5-mm safety margin around the visible magnetic resonance imaging (MRI) lesion. Follow-up included recording Clavien complications, Expanded Prostate Cancer Index Composite (EPIC) questionnaires (baseline, 1.5, 3, 6 months), 6-month multi-parametric MRI (mp-MRI) and 7-month biopsy. Findings on mp-MRI and biopsy were sub-divided into infield, adjacent or outfield of the treatment zone. RESULTS: Twenty-five men were included for final analysis. Safety follow-up revealed one Clavien Grade 3 complication and five Grade 1 complications. Functional follow-up confirmed no significant change in American Urological Association urinary symptom score, sexual or bowel function. Infield, there were no suspicious findings on mp-MRI (n=24) or biopsy (n=21) in all patients. Adjacent to the treatment zone, five (21%) had suspicious findings on mp-MRI with four (19%) proving to be significant on biopsy. Outfield, there were two (8%) with suspicious findings on mp-MRI and one (5%) significant finding on biopsy. For the five patients with significant findings on follow-up biopsy, one is awaiting repeat IRE, one had radical prostatectomy and three remained on active surveillance. CONCLUSIONS: In selected patients with low-intermediate risk PCa, focal IRE appears to be safe with minimal morbidity. There were no infield recurrences and 76% of patients were histologically free of significant cancer at 8 months. Almost all recurrences were adjacent to the treatment zone, and this was addressed by widening the treatment margins.


Subject(s)
Electrochemotherapy , Neoplasm Recurrence, Local/therapy , Prostate/diagnostic imaging , Prostatic Neoplasms/therapy , Adult , Aged , Biopsy , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Neoplasm Recurrence, Local/diagnostic imaging , Neoplasm Recurrence, Local/pathology , Neoplasm Staging , Prostate/pathology , Prostatectomy , Prostatic Neoplasms/diagnostic imaging , Prostatic Neoplasms/pathology , Radiography , Treatment Outcome
10.
Prostate Cancer Prostatic Dis ; 14(1): 58-62, 2011 Mar.
Article in English | MEDLINE | ID: mdl-20975738

ABSTRACT

PSA levels have shown daily and seasonal variation, although data are conflicting regarding the season with higher PSA levels and the clinical relevance of this. We assessed the correlation of total PSA levels with meteorological data on a daily, weekly, monthly and seasonal basis. Data from 53,224 men aged 45-74 years, with an initial PSA <10.0 ng ml(-1) were correlated with temperature (°C), duration of bright sunshine (hours) and rainfall (mm). There was seasonal variation in PSA levels, with median PSA being higher in spring compared with other seasons (1.18 vs 1.10 ng ml(-1), P = 0.004). Seasonal variation was not apparent when PSA levels were age-adjusted (P = 0.112). Total PSA was not correlated with daily, weekly or monthly hours of sunshine, rainfall or mean temperature. In contrast, age-adjusted PSA varied with weekday, with higher PSA levels on Thursday and Friday compared with other days (1.16 vs 1.10 ng ml(-1), respectively). On multivariate analysis, only age predicted for PSA levels >3.0 ng ml(-1). In conclusion, PSA levels did show seasonal variation, although there was no direct correlation between PSA and any meteorological parameter. The degree of seasonal variation is small and the decision to proceed to prostate biopsy should be independent of season or weather parameters.


Subject(s)
Prostate-Specific Antigen/blood , Seasons , Weather , Age Factors , Aged , Humans , Ireland , Male , Middle Aged , Prostate/pathology , Temperature , Time Factors
11.
Eur J Cancer ; 46(17): 3061-7, 2010 Nov.
Article in English | MEDLINE | ID: mdl-21047587

ABSTRACT

BACKGROUND: To assess the agreement between the causes of death assigned by a blinded and uniform review panel of the Rotterdam section of the European Randomised Study of Screening for Prostate Cancer and the official vital statistics and to explore the possible effect of the use of either of these two sources on the outcome of the screening trial. METHODS: A total of 670 deaths amongst men with prostate cancer, reviewed by the causes of death committee (CODC) up to 31st December 2006 were included in this study. The kappa statistics with confidence intervals (CI), sensitivity and specificity of the official statistics were determined, with the CODC considered the gold standard. The rate ratio (RR) and 95% confidence intervals (95% CI) for prostate cancer mortality, official statistics relative to CODC, were calculated following the Mantel-Haenszel procedure. RESULTS: The overall concordance and the kappa between official statistics and the CODC were 90.6% and 0.76 (0.71-0.82), remaining comparable when only the CODC category definitely prostate cancer was applied, with the sensitivity of official statistics increasing from 88.3% to 91.3% and specificity hardly changing (91.3% and 90.5%). High specificity and lower sensitivity is observed in the screening arm, whilst the opposite was seen in the control arm in men aged 55-69 and 70-74 years at entry. Considerable lower false positive rate was seen for both age groups in the screening arm (3.9% and 4.7%) compared to the control arm (8.4% and 14.3%). A statistically significant excess of prostate cancer death was observed for the official statistics in the age group 70-74 years, 1.53 (1.07-2.19), whilst it was not significant for men aged 55-69 at entry, 1.06 (0.83-1.36). CONCLUSION: In the Rotterdam ERSPC section, official statistics tended to overreport prostate cancer as an underlying cause of death, particularly in the age group 70-plus in the control arm, which would overestimate the true effect in favour of screening.


Subject(s)
Prostate-Specific Antigen/blood , Prostatic Neoplasms/mortality , Age Distribution , Aged , Aged, 80 and over , Cause of Death , Early Detection of Cancer/methods , Early Detection of Cancer/standards , Humans , Male , Middle Aged , Multicenter Studies as Topic , Netherlands/epidemiology , Prognosis , Prostatic Neoplasms/diagnosis , Randomized Controlled Trials as Topic
12.
Prostate Cancer Prostatic Dis ; 13(3): 218-27, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20680029

ABSTRACT

The objective of this study was to determine whether screening for prostate cancer (PC) reduces PC mortality and, if so, whether the required criteria to be introduced as a population-based screening program are satisfied. A literature review was conducted through electronic scientific databases. The screening tests, that is, PSA and digital rectal examination, have limited sensitivity and specificity for detecting PC; screening produces a beneficial stage shift and reduces PC mortality. Nevertheless, PC screening causes a large increase in the cumulative incidence, and the understanding of the economic cost and quality-of-life parameters are limited. PC screening cannot be justified yet in the context of a public health policy.


Subject(s)
Digital Rectal Examination , Health Plan Implementation , Prostate-Specific Antigen/blood , Prostatic Neoplasms/diagnosis , Humans , Male , Mass Screening/legislation & jurisprudence , Mass Screening/methods
13.
Cancer Causes Control ; 21(9): 1523-31, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20514514

ABSTRACT

OBJECTIVES: To investigate the impact of different PSA testing policies and health-care systems on prostate cancer incidence and mortality in two countries with similar populations, the Republic of Ireland (RoI) and Northern Ireland (NI). METHODS: Population-level data on PSA tests, prostate biopsies and prostate cancer cases 1993-2005 and prostate cancer deaths 1979-2006 were compiled. Annual percentage change (APC) was estimated by joinpoint regression. RESULTS: Prostate cancer rates were similar in both areas in 1994 but increased rapidly in RoI compared to NI. The PSA testing rate increased sharply in RoI (APC = +23.3%), and to a lesser degree in NI (APC = +9.7%) to reach 412 and 177 tests per 1,000 men in 2004, respectively. Prostatic biopsy rates rose in both countries, but were twofold higher in RoI. Cancer incidence rates rose significantly, mirroring biopsy trends, in both countries reaching 440 per 100,000 men in RoI in 2004 compared to 294 in NI. Median age at diagnosis was lower in RoI (71 years) compared to NI (73 years) (p < 0.01) and decreased significantly over time in both countries. Mortality rates declined from 1995 in both countries (APC = -1.5% in RoI, -1.3% in NI) at a time when PSA testing was not widespread. CONCLUSIONS: Prostatic biopsy rates, rather than PSA testing per se, were the main driver of prostate cancer incidence. Because mortality decreases started before screening became widespread in RoI, and mortality remained low in NI, PSA testing is unlikely to be the explanation for declining mortality.


Subject(s)
Prostate-Specific Antigen/blood , Prostatic Neoplasms/diagnosis , Prostatic Neoplasms/epidemiology , Age Distribution , Aged , Biopsy , Humans , Incidence , Ireland/epidemiology , Male , Middle Aged , Northern Ireland/epidemiology , Prostatic Neoplasms/blood , Registries
14.
J Rehabil Res Dev ; 37(4): 395-403, 2000.
Article in English | MEDLINE | ID: mdl-11028695

ABSTRACT

Bracing is a common modality in treating spinal fractures. Its objective is to reduce spinal movements and to stabilize the fracture. Until now, factual insight into the movement-reducing properties of Thoraco-Lumbar-Sacral Orthoses (TLSOs) has been missing. Two common TLSOs (e.g., Jewett and Voigt-Bähler) were tested for their movement-reducing properties in two small groups of healthy subjects. In the first study, maximal gross spinal movements, with and without a TLSO, were measured by means of a Portable Posture Registration Set (PPRS) in three different planes. In the second study, maximal segmental vertebral movements in the regions T10 to L4 were measured via X-rays. With few notable exceptions, wearing a TLSO, as measured by the PPRS and X-ray techniques, significantly reduced the segmental as well as gross spinal movements. However, the amount of movement reduction varied greatly from subject-to-subject and was sometimes small. Unfortunately, data are lacking on the amount of movement reduction that is clinically relevant.


Subject(s)
Braces , Range of Motion, Articular , Spine/physiology , Adult , Equipment Design , Humans , Lumbar Vertebrae/physiology , Male , Reference Values , Sacrum/physiology , Sensitivity and Specificity , Thoracic Vertebrae/physiology
15.
Photosynth Res ; 38(2): 169-76, 1993 Nov.
Article in English | MEDLINE | ID: mdl-24317913

ABSTRACT

Flash-induced redox reactions in spinach PS II core particles were investigated with absorbance difference spectroscopy in the UV-region and EPR spectroscopy. In the absence of artificial electron acceptors, electron transport was limited to a single turnover. Addition of the electron acceptors DCBQ and ferricyanide restored the characteristic period-four oscillation in the UV absorbance associated with the S-state cycle, but not the period-two oscillation indicative of the alternating appearance and disappearance of a semiquinone at the QB-site. In contrast to PS II membranes, all active centers were in state S1 after dark adaptation. The absorbance increase associated with the S-state transitions on the first two flashes, attributed to the Z(+)S1→ZS2 and Z(+)S2→ZS3 transitions, respectively, had half-times of 95 and 380 µs, similar to those reported for PS II membrane fragments. The decrease due to the Z(+)S3→ZS0 transition on the third flash had a half-time of 4.5 ms, as in salt-washed PS II membrane fragments. On the fourth flash a small, unresolved, increase of less than 3 µs was observed, which might be due to the Z(+)S0→ZS1 transition. The deactivation of the higher S-states was unusually fast and occurred within a few seconds and so was the oxidation of S0 to S1 in the dark, which had a half-time of 2-3 min. The same lifetime was found for tyrosine D(+), which appeared to be formed within milliseconds after the first flash in about 10% inactive centers and after the third and later flashes by active centers in Z(+)S3.

16.
Photosynth Res ; 38(3): 323-30, 1993 Jan.
Article in English | MEDLINE | ID: mdl-24317986

ABSTRACT

Redox changes of the oxygen evolving complex in PS II core particles were investigated by absorbance difference spectroscopy in the UV-region. The oscillation of the absorbance changes induced by a series of saturating flashes could not be explained by the minimal Kok model (Kok et al. 1970) consisting of a 4-step redox cycle, S0 → S1 → S2 → S3 → S0, although the values of most of the relevant parameters had been determined experimentally. Additional assumptions which allow a consistent fit of all data are a slow equilibration of the S3 state with an inactive state, perhaps related to Ca(2+)-release, and a low quantum efficiency for the first turnover after dark-adaptation. Difference spectra of the successive S-state transitions were determined. At wavelengths above 370 nm, they were very different due to the different contribution of a Chl bandshift in each spectrum. At shorter wavelengths, the S1 → S2 transition showed a difference spectrum similar to that reported by Dekker et al. 1984b and attributed to an Mn(III) to Mn(IV) oxidation. The spectrum of absorbance changes associated with the S2 → S3 transition was similar to that reported by Lavergne 1991 for PS II membranes. The S0 → S1 transition was associated with a smaller but still substantial absorbance increase in the UV. Differences with the spectra reported by Lavergne 1991 are attributed to electrostatic effects on electron transfer at the acceptor side associated with the S-state dependence of proton release in PS II membranes.

17.
Photosynth Res ; 28(3): 149-53, 1991 Jun.
Article in English | MEDLINE | ID: mdl-24414974

ABSTRACT

Pure and active oxygen-evolving PS II core particles containing 35 Chl per reaction center were isolated with 75% yield from spinach PS II membrane fragments by incubation with n-dodecyl-ß-D-maltoside and a rapid one step anion-exchange separation. By Triton X-100 treatment on the column these particles could be converted with 55% yield to pure and active PS II reaction center particles, which contained 6 Chl per reaction center.

18.
Eur J Vasc Surg ; 4(5): 503-6, 1990 Oct.
Article in English | MEDLINE | ID: mdl-2226883

ABSTRACT

The treatment of axillary-subclavian vein thrombosis is still controversial. Development of a post-phlebitic syndrome in patients treated conservatively occurs in many patients. Therefore more aggressive treatment is advocated. We report six patients treated with selective low-dose streptokinase infusion with excellent short-term results. Major complications did not occur. Recanalisation was observed in all patients. Long-term results are not yet available.


Subject(s)
Axillary Vein , Subclavian Vein , Thrombolytic Therapy , Thrombosis/drug therapy , Adult , Axillary Vein/diagnostic imaging , Female , Fluoroscopy , Humans , Male , Middle Aged , Streptokinase/administration & dosage , Streptokinase/therapeutic use , Subclavian Vein/diagnostic imaging , Thrombolytic Therapy/methods , Thrombosis/diagnostic imaging
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