IsletSwipe, a mobile platform for expert opinion exchange on islet graft images

We previously developed a deep learning-based web service (IsletNet) for an automated counting of isolated pancreatic islets. The neural network training is limited by the absent consensus on the ground truth annotations. Here, we present a platform (IsletSwipe) for an exchange of graphical opinions among experts to facilitate the consensus formation. The platform consists of a web interface and a mobile application. In a small pilot study, we demonstrate the functionalities and the use case scenarios of the platform. Nine experts from three centers validated the drawing tools, tested precision and consistency of the expert contour drawing, and evaluated user experience. Eight experts from two centers proceeded to evaluate additional images to demonstrate the following two use case scenarios. The Validation scenario involves an automated selection of images and islets for the expert scrutiny. It is scalable (more experts, images, and islets may readily be added) and can be applied to independent validation of islet contours from various sources. The Inquiry scenario serves the ground truth generating expert in seeking assistance from peers to achieve consensus on challenging cases during the preparation for IsletNet training. This scenario is limited to a small number of manually selected images and islets. The experts gained an opportunity to influence IsletNet training and to compare other experts' opinions with their own. The ground truth-generating expert obtained feedback for future IsletNet training. IsletSwipe is a suitable tool for the consensus finding. Experts from additional centers are welcome to participate.

Solution phase synthesis of the 14-residue peptaibol antibiotic trichovirin I

The 14-residue peptaibol antibiotic trichovirin I 4A of the structure Ac-Aib-L-Asn-L-Leu-Aib-L-Pro-L-Ala-L-Val-Aib-L-Pro-Aib-L-Leu-Aib-L-Pro-L-Leuol (Aib = alpha-aminoisobutyric acid, Leuol = leucinol) was synthesized by stepwise conventional solution phase synthesis using the Z/O tBu(OMe) strategy and HOBt/EDC as coupling reagents. Intermediates were fully characterized and the identity of the synthetic peptide with the component 4A of the natural, microheterogeneous peptide mixture was proven by electrospray mass spectrometry, HPLC, and bioassay.

Increased production of immune activation marker neopterin by colony-stimulating factors in gynecological cancer patients

Granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) have recently been introduced in the treatment of chemotherapy-induced neutropenia. Effects of these CSFs on the cellular immune system were evaluated in 38 neutropenic gynecological cancer patients during chemotherapy. In addition to restoring the leukocyte count, GM-CSF--to a greater extent than G-CSF--also induced neopterin, a sensitive marker of macrophages activated by interferons. This effect was confirmed in vitro by investigating the effects of these CSFs on interferon-gamma-mediated pathways in THP-I human myelomonocytic cells. The results suggest activation of immune effector cells by GM-CSF.

[The value of etoposide (VP-16) in the therapy of refractory ovarian cancer]

In analogy to Kühnle et al. (1984) the role of etoposide in patients with cisplatin-refractory ovarian cancer was evaluated. 45 patients were treated with 150-200 mg of etoposide per sa. m. on days 1-3. Acute toxicity was tolerable except alopecia grade III. Remarkable, however, was the induction of two fatal cases of leukaemia following etoposide treatment. The first patient, who was 27 years old, with FIGO stage IIb serous cystadenocarcinoma, which was treated with cisplatin/epirubicin and after a latent period of 45 months, a local recurrence was treated with 8 cycles of etoposide. Twenty-three months after discontinuation of etoposide therapy, the patient showed acute myelogenous leukaemia (AML) of M5b-subtype according to the FAB classification. Two days after diagnosis, the patient died of the disease. The second patient, a 55-year old woman with FIGO stage IIa serous cystadenocarcinoma, was treated with cisplatin/cytoxan; 8 cycles of etoposide were given as a second line therapy. This patient, 21 months after discontinuation of etoposide therapy showed a pre-pre-B-acute lymphocytic leukaemia with coexpression of the myeloid antigens. Two months after diagnosis, the patient died of the disease. In 4 out of 38 patients, a complete and in 7 patients a partial remission was induced by etoposide treatment and survival of these responding patients was prolonged in comparison with the nonresponder. The survival was also dependent on CA-125 serum level and the cumulative dose of etoposide administered. Etoposide treatment is an acceptable option as salvage therapy in refractory ovarian cancer.(ABSTRACT TRUNCATED AT 250 WORDS)

[Comparison of conventional radium and high dose rate afterloading brachytherapy in cervix cancer]

The combination of intracavitary and external-beam radiation is the treatment of choice in advanced cervical cancer. Low-dose regimens using radium were widely abandoned in favour of high-dose-rate afterloading systems. We compared in this retrospective analysis of 550 patients the 2 different treatment modalities. We could observe neither in overall survival, nor in the incidence of side effects, any significant difference. Although the change from low- to high-dose-rate radiation therapy was not accompanied by a benefit in survival, the latter modality displayed several advantages e.g. a reduced exposure of personnel to radiation and shorter duration of confinement to bed. Patient survival rate was dependent mainly on parameters of tumour burden (FIGO stage), i.v. pyelogram or CT scan of paraaortic lymph nodes. On the other hand, neither the histological classification as epidermoid or adenocarcinoma nor the WHO grading, were useful predictors of patient outcome.

[Prognostically relevant factors in malignant mixed Müllerian tumor]

In a retrospective analysis of 429 endometrial carcinoma and 29 malignant mixed Müllerian tumour (MMMT) patients, the prognostic factors were evaluated. More than 80% of endometrial carcinomata were staged as I or II, whereas about 30% of MMMT's already in stage III or IV (p less than 0.05). MMMT patients were 10 years older than the carcinoma group (73a vs 63a; p less than 0.001). The risk factors parity, adipositas, and diabetes were equally distributed in the two groups, the survival was worse in MMMT (p less than 0.0001). Applying univariate analysis stage, grading, myometrial invasion and type of therapy significantly affected the survival of endometrial carcinoma patients. After a Cox regression, only stage and grading remained significantly associated with the prognosis. For MMMT's, the survival was also influenced by stage, myometrial invasion, and kind of therapy. Moreover, the parity was found to affect markedly the course of disease. Cox regression of our data excluded all but stage and parity. The beneficial influence of parity on the prognosis of MMMTs, despite a latency of more than 20 years from the last birth to tumour appearance, is unique in oncology.

Transforming growth factor-beta and ovarian carcinoma cells: regulation of proliferation and surface antigen expression

Transforming growth factor-beta (TGF-beta) is a multifunctional peptide regulating several processes in ovarian cells. The growth of ovarian carcinoma cell lines (OVCAR-3, HTB-77, 2780 and CRL-1572) was reduced by TGF-beta in a dose related manner. The antiproliferative activity was not improved by combination with other biological response modifiers. Treatment with TGF-beta augmented the expression of interferon-gamma induced class I and II antigens of the major histocompatibility complex. The presentation of another antigen namely the tumor marker CA-125 on the cell surface was markedly reduced by TGF-beta.

Neurotoxic aminoglycoside antibiotics are potent inhibitors of [125I]-Omega-Conotoxin GVIA binding to guinea-pig cerebral cortex membranes

[125I]-Omega-Conotoxin GVIA, a blocker of neuronal (N-type) calcium channels labelled 295 +/- 121 fmol per mg protein of high affinity sites (apparent half-saturation at 1.5 to 2.5 pmol/l) in guinea-pig cerebral cortex membranes. Divalent cations (Cd2+ greater than Ni2+ greater than Co2+ greater than Ca2+ greater than Sr2+ = Ba2+ greater than Mg2+) and La3+ were potent inhibitors of Omega-Conotoxin GVIA binding, whereas monovalent cations (Na+, K+, Li+) were ineffective up to 50 mmol/l. Aminoglycosides (neomycin greater than gentamycin = tobramycin greater than streptomycin greater than amikacin greater than kanamycin) and polymyxin B also inhibited [125I]-Omega-Conotoxin GVIA binding with IC50 values in the mumolar range. All other antibiotics tested were ineffective up to 1 mmol/l. With the exception of polymyxin B, which partially inhibited the binding of the 1,4-dihydropyridine (+)-[3H]PN 200-110 and of (-)-[3H]desmethoxyverapamil, the aminoglycosides and the other antibiotics had no effect on the L-type calcium channel labelling. It is suggested, that inhibition of neurotransmitter release by aminoglycosides is mediated via blockade of the N-type calcium channel to which [125I]-Omega-Conotoxin GVIA binds selectively in a quasi irreversible manner.