Some remarks on the Anatomy of the Melanotaeniinae

The freshwater of Australia, New Guinea and some of the neighbouring islands are inhabited by peculiar fishes belonging to the Atherinidae and which are chiefiy distinguished by their compressed elevated form, long second dorsal and anal fins and generally by the presence of strong pungent spines in dorsals, anal and ventrals. The upperjaw is bent and provided with well developed teeth, which more or less extend to its outside. They are generally considered to form a distinct subfamily, the Melanotaeniinae. MAX WEBER (3) was the first to point out their importance from a geographical point of view. He considered them as freshwater-fishes, rarely found in brackish water, for which the sea forms an unpassable barrier. At the time WEBER wrote his paper, the Melanotaeniinae were only known from Australia and New Guinea, two landmasses which certainly have been connected together in recent geological times. His prophecy, that they might occur in the islands near New Guinea, which also have been connected with the larger island, has been prooved to be true later (WEBER 4, DE BEAUFORT 1) and has greatly strengthened his opinion on the distribution of these fishes

On some Indo-Pacific Genera of Labroid fishes, with the description of a new genus and species

In 1853 BLEEKER (I, p. 489 and 490) described two species, both from the bay of Batavia, as Julis (Halichoeres) cyanopleura and Julis (Halichoeres) pyrrhogrammatoides. He pointed out that these two species are closely related, the first to Julis poecilopterus SCHL., the second to Julis pyrrhogramma SCHL., both from Japan. Lastnamed species differ from the javanese species, besides by slightly different colourmarkings, by having 14 rays in the dorsal and the anal, against 11 rays in both fins of the javanese species. BLEEKER says that but for the difference in the number of dorsal and anal rays, which is considerable, at least for this genus, he would be temped to consider the javanese species as climatic variations (“klimaatvarieteiten”) of the japanese ones. He also draws attention to the great resemblance of these four species inter se, as they are all characterised by having 4 canines anteriorly in each jaw, and the outer pair in the upper jaw greatly curved backwards. When at a later date (2, p. 100) he found that the pharyngealia inferiora of H. cyanopleura and H. pyrrhogrammatoides differ from those of the other members of the genus Halichoeres by being concave posteriorly, he created a new genus Leptojulis with L. cyanopleura as the type. It is curious that in the discussion of this new genus in the Atlas Ichthyologique (3, p. 128) BLEEKER says: “Je ne connais du genre Leptojulis que les deux espèces de mon cabinet, qui toutes les deux habitent la mer de Batavia”, and that no mention is made of the two japanese species, which formerly he considered to be so very closely related to them. We can guess why he did so, for some years later (4, p. 251) he gave an elaborate description of Julis poecilopterus and pyrrhogramma. The inferior pharyngeals are described as being not concave behind and agreeing in all respects with those of other species of Halichoeres, in which genus he now places the two species. Again, no mention is made of his species of Leptojulis, but the japanese species are now compared with Halichoeres bicolor and hyrtli, which have the same disposition of bands on the body, but differ in the number of canines and in the number of dorsal and anal rays

Freshwater fishes from the Leeward Group, Venezuela and eastern Colombia

This paper contains the results of the study of the fish-collection, made by P. Wagenaar Hummelinck, on the islands of the Leeward Group and some parts of the adjacent South-American continent, in 1936—’37 and in 1930. The latter have already been studied by Miss M. Sanders (1936) and are only included for completeness’ sake. The material has been presented to the Zoological Museum of Amsterdam

Generating human prostate cancer organoids from leukapheresis enriched circulating tumour cells

Background: Circulating tumour cell (CTC)–derived organoids have the potential to provide a powerful tool for personalised cancer therapy but are restrained by low CTC numbers provided by blood samples. Here, we used diagnostic leukapheresis (DLA) to enrich CTCs from patients with metastatic prostate cancer (mPCa) and explored whether organoids provide a platform for ex vivo treatment modelling. Methods: We prospectively screened 102 patients with mPCa and performed DLA in 40 patients with ≥5 CTCs/7.5 mL blood. We enriched CTCs from DLA using white blood cell (WBC) depletion alone or combined with EpCAM selection. The enriched CTC samples were cultured in 3D to obtain organoids and used for downstream analyses. Results: The DLA procedure resulted in a median yield of 5312 CTCs as compared with 22 CTCs in 7.5 mL of blood. Using WBC depletion, we recovered 46% of the CTCs, which reduced to 12% with subsequent EpCAM selection. From the isolated and enriched CTC samples, organoid expansion succeeded in 35%. Successful organoid cultures contained significantly higher CTC numbers at initiation. Moreover, we performed treatment modelling in one organoid cell line and identified substantial tumour heterogeneity in CTCs using single cell DNA sequencing. Conclusions: DLA is an efficient method to enrich CTCs, although the modest success rate of culturing CTCs precludes large scale clinical application. Our data do suggest that DLA and subsequent processing provides a rich source of viable tumour cells. Therefore, DLA offers a promising alternative to biopsy procedures to obtain sufficient number of tumour cells to study sequential samples in patients with mPCa. Trial registration number: NL6019.</p