Morphological and functional seed traits of the wild medicinal plant Dioscorea strydomiana, the most threatened yam in the world.

Morphological and functional seed traits have important roles in characterising the species regeneration niche and help to understand the reproductive biology of rare and threatened plants, which can thus support appropriate plant conservation measures. Seed morphometric and dispersal kinetics of the critically endangered Dioscorea strydomiana were measured and compared with those of four other Dioscorea species, and seed germination response under constant temperatures (5-35 °C) was compared with that of the congeneric and widespread D. sylvatica. Seed mass of D. strydomiana (ca. 14 mg) was twice that of D. sylvatica, but similar to or smaller than the other species examined. Seeds of D. strydomiana have the lowest speed of descent and lowest variability in most of the morphological traits considered, suggesting lower phenotypic plasticity but higher variance in the wing-loading value. Seeds of D. strydomiana reached maximum germination at 15 °C (ca. 47%), which decreased slightly to ca. 37% at 25 °C and was completely inhibited at 35 °C. D. sylvatica seeds started to germinate at 10 °C (ca. 3%), reached 75-80% germination at 15-20 °C and maximum (ca. 90%) at 25-30 °C. Base temperatures for germination (Tb ) were 9.3 and 5.7 °C, for D. strydomiana and D. sylvatica, respectively. Due to the higher germination percentages of D. sylvatica, ceiling and optimum temperatures could also be modelled for this species, suggesting higher sensitivity to high temperature for seeds of D. strydomiana. The detected poor seed lot quality of D. strydomiana suggests difficulties in reproduction from seed, highlighting the need for further investigation and conservation actions for this threatened yam species.

Liability under post-tonsillectomy lethal bleeding of the tonsillar artery: a report of two cases.

Post-operative haemorrhage is a frequent complication of tonsillectomy: a primary haemorrhage occurring in the first hours is rapidly dealt with by the surgical team. A secondary haemorrhage, which commonly occurs once the child has returned home, can be fatal if it is not dealt with quickly. We present two cases of a lethal outcome in children following a secondary post-tonsillectomy haemorrhage, for which the parents filed legal proceedings. Medical liability can be exercised during all stages of health care. Performing an autopsy associated with histological analyses is found to be indispensable for the identification of the causes of bleeding, as well as its mechanism.

Protocol-based image-guided salvage brachytherapy. Early results in patients with local failure of prostate cancer after radiation therapy.

PURPOSE: To assess the overall clinical outcome of protocol-based image-guided salvage pulsed-dose-rate brachytherapy for locally recurrent prostate cancer after radiotherapy failure particularly regarding feasibility and side effects. PATIENTS AND METHODS: Eighteen consecutive patients with locally recurrent prostate cancer (median age, 69 years) were treated during 2005-2011 with interstitial PDR brachytherapy (PDR-BT) as salvage brachytherapy after radiotherapy failure. The treatment schedule was PDR-BT two times with 30 Gy (pulse dose 0.6 Gy/h, 24 h per day) corresponding to a total dose of 60 Gy. Dose volume adaptation was performed with the aim of optimal coverage of the whole prostate (V100 > 95 %) simultaneously respecting the protocol-based dose volume constraints for the urethra (D0.1 cc < 130 %) and the rectum (D2 cc < 50-60 %) taking into account the previous radiation therapy. Local relapse after radiotherapy (external beam irradiation, brachytherapy with J-125 seeds or combination) was confirmed mostly via choline-PET and increased PSA levels. The primary endpoint was treatment-related late toxicities--particularly proctitis, anal incontinence, cystitis, urinary incontinence, urinary frequency/urgency, and urinary retention according to the Common Toxicity Criteria. The secondary endpoint was PSA-recurrence-free survival. RESULTS: We registered urinary toxicities only. Grade 2 and grade 3 toxicities were observed in up to 11.1 % (2/18) and 16.7 % (3/18) of patients, respectively. The most frequent late-event grade 3 toxicity was urinary retention in 17 % (3/18) of patients. No late gastrointestinal side effects occurred. The biochemical PSA-recurrence-free survival probability at 3 years was 57.1 %. The overall survival at 3 years was 88.9 %; 22 % (4/18) of patients developed metastases. The median follow-up time for all patients after salvage BT was 21 months (range, 8-77 months). CONCLUSION: Salvage PDR-brachytherapy of the prostate following local failure after radiation therapy is a treatment option with a low rate of genitourinary side effects and no late gastrointestinal side effects. The treatment efficacy in the first 3 years is promising.

Evaluation of an uncollimated printed paper transmission source used under scatter limiting conditions.

Transmission sources used for image attenuation correction, allowing image quantification, are collimated to reduce scatter. We propose the same effect can be achieved for an uncollimated source by increasing source to patient distance. The aim was to compare planar image performance characteristics and absorbed doses of uncollimated and collimated radioactive printed paper transmission sources. The scatter contribution to the uncollimated (99m)Tc source data was evaluated for different combinations of detector phantom distance, detector source distance and phantom source distance. Measurements were performed by increasing the Lucite phantom thickness in 1cm steps to 20 cm. Spatial resolution, detection efficiency and entrance absorbed dose rate were measured for the uncollimated and collimated transmission source images. Results derived from the energy spectra, obtained with the uncollimated transmission source indicate that scatter contribution increases with decreasing detector source distance. The scatter component in the uncollimated transmission images (detector source distances ≥ 60 cm; phantom source distances ≥ 40 cm) was comparable to that obtained with collimated transmission images. Attenuation coefficients obtained compared well (0.168 cm⁻¹ vs. 0.171 cm⁻¹). The full widths at half maxima differed by less than 0.9 mm. The detection efficiency of the uncollimated source was 2.5 times higher than obtained with the collimated source. The entrance absorbed dose obtained from an uncollimated source was 3.75 times larger than that obtained from the collimated source. An uncollimated transmission source (detector source distance ≥ 60 cm) results in acceptable image characteristics and presents a low cost, low dose, high efficiency option for transmission imaging.

[Marks on the human and animal skin after contact with an electrical discharge device].

Skin injuries in a subject affected by the current generated in an electrical discharge device are described. The macroscopic and microscopic picture of the injuries inflicted with the use of a similar device in experimental animals is presented.

[Postmortem differential diagnostics of diabetic and alcoholic ketoacidosis].

It was shown that ketoacidosis may be an immediate cause of death in subjects suffering chronic alcoholic intoxication. The authors present a list of biochemical studies and parameters that can be used for differential diagnosis between diabetic and alcoholic ketoacidosis.

Production of radioactive quality assurance phantoms using a standard inkjet printer.

This note proposes the use of a standard inkjet printer to produce radioactive (99m)Tc phantoms that can be used for routine quality control of gamma cameras. The amount of activity that will be deposited on paper per unit area was predicted and compared to the measured activity. The uniformity of the printouts was compared to the uniformity obtained with a standard (57)Co flood source. A scintillation detector connected to a multi-channel analyzer was used to evaluate the uniformity of the printout independently from the gamma camera. Joining two A4 size printed phantoms to create larger sources was evaluated. The spatial resolution obtained with printed sources was compared to that obtained using standard line source techniques. The results indicated that the uniformity of the printed phantoms compared well with those obtained with the (57)Co flood source (integral uniformity 2.29% (printed source) and 2.10% ((57)Co flood source)). There was no difference in the resolution measurements obtained with the printed sources and those obtained with the standard methods. This study demonstrates that affordable phantoms can easily be created to evaluate system uniformity and resolution in any department where a standard PC and inkjet printer are available.

[High-dose 106Ruthenium plaque brachytherapy for posterior uveal melanoma. A clinico-pathologic study]. / Hochdosisbrachytherapie des malignen Aderhaut- und Ziliarkörpermelanoms mit 106Ruthenium. Eine klinisch-pathologische Studie.

BACKGROUND: The purpose of this study was to report the multifactorial results of high-dose (106)Ruthenium plaque brachytherapy for (cilio-)choroidal melanoma and to confirm them by histological examinations. PATIENTS AND METHODS: 100 patients with choroidal or ciliochoroidal melanoma treated by high-dose 106Ruthenium plaque brachytherapy were followed-up for 5 years. 12 secondary enucleated eyes were compared to a non-irradiated matched group by light microscopy. RESULTS: The 5-year local tumour control rate was 93%, the 5-year survival rate 91%. Late radiogenic side effects occured as a retinopathy in 13%, as an optic neuropathy in 5% and as a secondary glaucoma in 3% of the patients. 14% had to be enucleated, 10% developed metastases. The histopathologic examination revealed significantly higher degrees of necrosis (p=0,041), balloon cell degeneration (p=0,025) and fibrosis (p<0,001) in the irradiated melanomas than in the control tumours. CONCLUSION: High-dose 106Ruthenium plaque brachytherapy turned out to be an effective treatment procedure for posterior uveal melanoma (not exceeding a prominence of 5,5 mm) with a high rate of local tumour control and a low rate of side effects.

[Partial breast irradiation for early breast cancer with favorable prognostic factors: 3-year results of the German-Austrian phase II-trial]. / Teilbrustbestrahlung beim Mammakarzinom mit günstigen prognostischen Faktoren: 3-Jahres-Ergebnisse der deutsch-österreichischen Phase II-Studie.

PURPOSE: To evaluate perioperative morbidity, toxicity and cosmetic outcome in patients treated with interstitial brachytherapy to the tumor bed as the sole radiation modality after breast conserving surgery. MATERIALS AND METHODS: From 11/2000 to 11/2004, 240 women with early stage breast cancer participated in a protocol of tumor bed irradiation alone using pulsed dose rate (PDR) or high dose rate (HDR) interstitial multi-catheter implants (partial breast irradiation). Perioperative morbidity, acute and late toxicity as well as cosmetic outcome were assessed. Of the first 51 patients treated in this multicenter trial, we present interim findings after a median follow-up of 36 months. RESULTS: Perioperative Morbidity: Bacterial infection of the implant: 2 % (1/51). Acute toxicity: radiodermatitis Grade 1: 4 % (2/51). Late toxicity: breast pain Grade 1: 8 % (4/51), Grade 2: 2 % (1/51); dyspigmentation Grade 1: 8 % (4/51); fibrosis Grade 1: 4 % (2/51), Grade 2: 8 % (4/51); telangiectasia Grade 1: 10 % (5/51), Grade 2: 4 % (2/51). Cosmetic results: Excellent and good in 94 % (48/51) of the patients. CONCLUSION: This analysis indicates that accelerated partial breast irradiation with 192-iridium interstitial multicatheter PDR-/HDR-implants (partial breast irradiation) is feasible with low perioperative morbidity, low acute and mild late toxicity at a median follow-up of 36 months. The cosmetic result is not significantly affected.

Left ventricular ejection fraction calculated from gated technetium-99-sestamibi SPECT.

BACKGROUND: The accuracy of the left ventricular ejection fraction (LVEF) calculated from gated single photon emission computed tomography (GSPECT) studies is dependent on the accuracy of the determination of the end-diastolic volume (EDV) and end-systolic volume (ESV) of the left ventricle (LV). In this study we evaluated the feasibility of calculating the EDV, ESV and LVEF from the area under the polar graph (APC) of the edges of the LV image determined by a first derivative edge-detection method. METHODS AND RESULTS: Technetium-99m ((99m)Tc) sestamibi GSPECT studies and planar equilibrium radionuclide ventriculography (ERNV) were performed on 15 male subjects in whom the LVEF ranged from 19% to 75%. Images were reconstructed to obtain short axis slices of the LV spanning the cardiac cycle. On each slice the LV edge points were determined at 10 degrees intervals using the APC method. The area of each short axis slice was determined by conversion to polar co-ordinates, interpolation and numerical integration of the graphs and multiplication by a pre-determined conversion factor. RESULTS: Edges were successfully determined in all 15 patients using the APC method. The LVEF results correlate well with conventional planar ERNV studies (r = 0.96, LVEF(GSPECT) = 8.80 + 0.66 LVEF( ERNV)). The absolute difference between the LVEF for ERNV and for the APC method was 6.1% with a standard deviation of 7.6%. The reproducibility of SPECT LVEF using the APC method was good (intra-observer r = 0.99, inter-observer r = 0.99). CONCLUSIONS: The APC method provides for easy and accurate ejection fraction determination with limited underlying mathematical assumptions. The ability to interpolate the edge points provides for stable edge detection even in hypoperfused myocardium.

Comparison of the Batho, ETAR and Monte Carlo dose calculation methods in CT based patient models.

This paper shows the contribution that Monte Carlo methods make in regard to dose distribution calculations in CT based patient models and the role it plays as a gold standard to evaluate other dose calculation algorithms. The EGS4 based BEAM code was used to construct a generic 8 MV accelerator to obtain a series of x-ray field sources. These were used in the EGS4 based DOSXYZ code to generate beam data in a mathematical water phantom to set up a beam model in a commercial treatment planning system (TPS), CADPLAN V.2.7.9. Dose distributions were calculated with the Batho and ETAR inhomogeneity correction algorithms in head/sinus, lung, and prostate patient models for 2 x 2, 5 x 5, and 10 X 10 cm2 open x-ray beams. Corresponding dose distributions were calculated with DOSXYZ that were used as a benchmark. The dose comparisons are expressed in terms of 2D isodose distributions, percentage depth dose data, and dose difference volume histograms (DDVH's). Results indicated that the Batho and ETAR methods contained inaccuracies of 20%-70% in the maxillary sinus region in the head model. Large lung inhomogeneities irradiated with small fields gave rise to absorbed dose deviations of 10%-20%. It is shown for a 10 x 10 cm2 field that DOSXYZ models lateral scatter in lung that is not present in the Batho and ETAR methods. The ETAR and Batho methods are accurate within 3% in a prostate model. We showed how the performance of these inhomogeneity correction methods can be understood in realistic patient models using validated Monte Carlo codes such as BEAM and DOSXYZ.

Implementation of a Tc-99m and Ce-139 scanning line source for attenuation correction in SPECT using a dual opposing detector scintillation camera.

Image degradation during single photon emission computed tomography (SPECT) due to attenuation and Compton scatter of photons can cause clinical image artifacts and will also result in inaccurate quantitative data. Therefore attenuation correction methods recently received wide interest. Transmission imaging can be performed to obtain the attenuation coefficients of a nonhomogeneous attenuating medium accurately. The aim of this study was firstly to evaluate the imaging characteristics of the scanning line source assembly. The results obtained with Tc-99m and Ce-139 were compared. Secondly the calculated attenuation coefficients were compared with known values from literature, using Tc-99m and Ce-139 as transmission sources. Lastly the method of acquiring simultaneous transmission and emission data was investigated. This study shows that an attenuation coefficient map can be obtained using a scanning line source for transmission imaging with a dual opposing detector camera. The imaging characteristics of Tc-99m and Ce-139 as transmission sources are similar. The resolution obtained with the Ce-139 line source was poorer than that obtained with the Tc-99m line source. A linear relationship was found between CT numbers and attenuation coefficients for transmission images using both Tc-99m and Ce-139 line sources. The attenuation coefficient value for water was underestimated by 1% using the Tc-99m transmission source and underestimated by 10% using Ce-139 as transmission source. This underestimation of attenuation coefficient values was also obtained in the human study. A myocardial perfusion study processed without and with attenuation correction clearly demonstrated the effect of the attenuation correction in the inferior myocardial region. The potential of using a scanning line source as transmission source with a dual opposing detector camera has been demonstrated in this study. The transmission source, Ce-139 was successfully introduced in this investigation for simultaneous acquisition of transmission and emission data.

Measurement of plasma volume using 99Tc(m)-labelled DMP-HSA.

Red cell volume (RCV) and plasma volume (PV) measurements are performed routinely in nuclear medicine departments to diagnose a number of haematological disorders. Currently, 125I-HSA is used as a plasma tracer and 99Tcm-labelled red cells to determine red cell volume. 125I-HSA is not always readily available, leading to inconvenience for patients and medical practitioners. Due to the availability of 99Tcm in nuclear medicine departments, the use of albumin labelled with 99Tcm was investigated. A new 99Tcm-human serum albumin labelling kit (99Tcm-DMP-HSA) was developed by Verbeke and supplied for use in this study. The main aim of the study was to investigate the use of 99Tcm-DMP-HSA for PV determination. Secondly, the feasibility to determine red cell and plasma volume simultaneously using 99Tcm as radionuclide in both instances was investigated. Fourteen healthy volunteers were enrolled in the dual-phase study. During the first study, 99Tcm-DMP-HSA was used as tracer to calculate PV (PV1a) after intravenous administration. Subsequently, 99Tcm-labelled red cells were administered and the PV (PV1b) and RCV (RCV1) were calculated. The second study was repeated within 2 weeks using the conventional method. 125I-HSA and 99Tcm-labelled red cells were administered simultaneously. The PV (PV2) and RCV (RCV2) were calculated. We found that the redistribution of 99Tcm-DMP-HSA is faster than that of 125I-HSA; therefore, the plasma counts obtained at different times were back-extrapolated to time zero for plasma volume calculations. The mean values for the different calculated PVs were 2964+/-470 ml for PV1a, 3006+/-623 ml for PV1b and 3001+/-530 ml for PV2, the reference PV. The confidence intervals indicate no significant differences between plasma volumes PV1a and PV2 and plasma volumes PV1a and PV1b. The mean calculated RCV1 was 2130+/-322 ml; that of RCV2 was 2128+/-353 ml. The difference between RCV1 and RCV2 was not significant. Our results indicate that 99Tcm-DMP-HSA could be used for plasma volume calculation. Red cell and plasma volumes can be calculated simultaneously using 99Tcm as radionuclide in both cases.

Early results of pulsed-dose-rate interstitial brachytherapy for head and neck malignancies after limited surgery.

PURPOSE: The aim of this study was to evaluate the relative incidence of toxicity and local control in patients with head and neck malignancies who underwent interstitial pulsed-dose-rate (PDR) brachytherapy (iBT). PATIENTS AND METHODS: From October 1997 to December 1998, 61 patients underwent interstitial PDR brachytherapy procedures in our department; 47 were patients with head and neck cancer. Forty patients received brachytherapy as part of their curative treatment regimen, and 7 patients were implanted for palliative purposes and excluded from the analysis of therapy efficacy. Twenty-four patients had interstitial brachytherapy procedures alone with D(REF) = 50 Gy; in 23 patients, iBT procedures were performed with D(REF) = 24 Gy in combination with external radiation. A dose per pulse (dp) of 0.5 Gy was prescribed for 38/47 patients, and a dp = 0.7 Gy for 9/47 patients. The pulses were delivered 24 h a day, with a time interval of 1 h between two pulses, resulting in an effective dose rate of 0.5 Gy/h or 0.7 Gy/h. A follow-up of the patients was done to analyze acute and delayed toxicity, local control, and survival. The analysis was performed after median follow-up of 12 months (5-18 months). RESULTS: After a median follow-up of 12 months, soft tissue necrosis was seen in one patient and bone necrosis in another. No other serious side effects were observed. Permanent locoregional tumor control was achieved in 37 of 40 patients. No distant metastases were observed. CONCLUSIONS: PDR interstitial brachytherapy with 0.5-0.7 Gy/h is a safe therapy. These preliminary results suggest that PDR interstitial brachytherapy of head and neck cancer is comparable with low-dose-rate (LDR) brachytherapy.

Effect of novel water-soluble polymeric forms of sorbic acid against Fusarium oxysporum f.sp. radicis-cucumerinum.

New controlled release water-soluble formulations of sorbic (2,4-hexadienoic) acid were prepared and their inhibitory activity on mycelium growth of Fusarium oxysporum f.sp. radicis-cucumerinum was evaluated. The new products are epoxidized polymers of polyvinylpyrrolidone (PVP) containing covalently bonded sorbic acid (polymeric esters of sorbic acid) and complexes of PVP with hydrogen bonded sorbic acid, characterized by controlled release of sorbic acid. It was shown that the polymeric complexes of sorbic acid with PVP were more effective fungicidal agents than sorbic acid polymeric esters. In all cases the activity of polymeric derivatives (esters and complexes) was increased by lowering the molecular weight of the polymeric carriers. Controlled release formulations of these polymeric derivatives are new promising products due to their low toxicity, wide range of efficient concentrations for application and ability to regulate lyophilicity. Our data contribute to the understanding of the action mechanism of various polymeric sorbic acid formulations and can result in products which are particularly suitable for food and feed protection applications.

Biodistribution and absorbed radiation dose estimates of 99mTc-labeled dimercaptopropionyl human serum albumin.

UNLABELLED: The use of 99mTc-labeled red blood cells (RBC) for the evaluation of left ventricular function using equilibrium-gated blood-pool imaging suffers from several problems and potential risks. In this study, we estimated the absorbed radiation dose of 99mTc-labeled dimercaptopropionyl human serum albumin (DMP-HSA) as a potential alternative to 99mTc-RBC. METHODS: After the administration of 99mTc-DMP-HSA, whole-body imaging was performed up to 48 h after injection in five volunteers. The heart contents, liver and remainder of the body were used as source organs. Multicompartment modeling of the biodistribution was performed and absorbed radiation dose estimates for 99mTc-DMP-HSA were obtained using the Medical Internal Radiation Dose (MIRD) calculation. RESULTS: Residence times of 0.62 and 0.43 h were obtained for the heart contents and liver, respectively. Radiation dose estimates yielded an effective dose of 0.0055 mSv/MBq. CONCLUSION: 99MTC-DMP-HSA yielded absorbed radiation doses comparable with those of 99mTc-RBC. Therefore, the radiation properties of 99mTc-DMP-HSA are such that it can be used for clinical diagnostic studies.

Sites of elimination and pharmacokinetics of recombinant [131I]lepirudin in baboons.

Lepirudin has a short half-life, and only 50-60% of the intravenously administered dose is excreted by the kidneys. The fate of the remainder is unknown. We designed a study to determine the fate of this lepirudin. In each of six baboons, [131I]lepirudin was given intravenously as a bolus or infused over 30 min, 24 h apart. The in vivo redistribution of [131I]lepirudin was determined and quantified by scintillation camera imaging. In all studies, the half-life of [131I]lepirudin, as determined from the disappearance of radioactivity, was 21 +/- 3 min. The half-life determined from the disappearance of lepirudin, measured by the Ecarin Clotting Time (ECT) method, was similar at 23 +/- 8 min. Results obtained with the labeled lepirudin are therefore comparable with those obtained using the plasma concentration of lepirudin. When lepirudin was administered as a bolus, the half-life was 18 +/- 4 min, and lepirudin was cleared from the plasma at a rate of 42 +/- 12 mL/min and by the kidneys at 23 +/- 2 mL/min. Following infusion over 30 min, the half-life and total and renal clearances were not significantly different. In both studies, between 50 and 60% of the administered lepirudin was excreted by the kidney. Studies on sacrificed baboons showed that appreciable amounts of lepirudin were present in the bile, indicating the liver as a contributor to the elimination of lepirudin.

[Biochemical studies in the postmortem diagnosis of the disseminated intravascular coagulation syndrome]. / Biokhimicheskie issledovaniia v posmertnoi diagnostike sindroma disseminirovannogo vnutrisosudistogo svertyvaniia.

Sulfite-alkaline method after Rampling and Gaffney is proposed for measuring fibrinogen and fibrin degradation products in cadaveric blood. Normal values for cadaveric blood are determined and qualitative paracoagulation tests proposed. Such biochemical studies can be used, along with histological, for more accurate postmortem diagnosis of the DIC syndrome.