Chylothorax is defined as the presence of chyle in the pleural cavity. Central vein thrombosis is an under-recognized cause of chylothorax in the adult population and is commonly related to central venous catheterization. Case 1 illustrates a patient with AIDS and disseminated tuberculosis with left chylothorax and central vein thrombosis after a month of antituberculosis therapy. Case 2 was a patient with advanced seminoma who presented with left chylothorax and central vein thrombosis while on chemotherapy. Chylothorax resolved with anticoagulation for both cases. Case 3 was a lymphoma patient with central vein thrombosis who developed chylothorax during chemotherapy. Chylothorax resolved with the continuation of anticoagulation and did not recur despite his progressive underlying lymphoma. There was no central venous catheterization in any of these three cases. These cases illustrate the unique association of central vein thrombosis and chylothorax and the importance of anticoagulation in its management.
The high species richness of tropical forests has long been recognized, yet there remains substantial uncertainty regarding the actual number of tropical tree species. Using a pantropical tree inventory database from closed canopy forests, consisting of 657,630 trees belonging to 11,371 species, we use a fitted value of Fisher's alpha and an approximate pantropical stem total to estimate the minimum number of tropical forest tree species to fall between ∼ 40,000 and ∼ 53,000, i.e., at the high end of previous estimates. Contrary to common assumption, the Indo-Pacific region was found to be as species-rich as the Neotropics, with both regions having a minimum of ∼ 19,000-25,000 tree species. Continental Africa is relatively depauperate with a minimum of ∼ 4,500-6,000 tree species. Very few species are shared among the African, American, and the Indo-Pacific regions. We provide a methodological framework for estimating species richness in trees that may help refine species richness estimates of tree-dependent taxa.
Knowledge about the biogeographic affinities of the world's tropical forests helps to better understand regional differences in forest structure, diversity, composition, and dynamics. Such understanding will enable anticipation of region-specific responses to global environmental change. Modern phylogenies, in combination with broad coverage of species inventory data, now allow for global biogeographic analyses that take species evolutionary distance into account. Here we present a classification of the world's tropical forests based on their phylogenetic similarity. We identify five principal floristic regions and their floristic relationships: (i) Indo-Pacific, (ii) Subtropical, (iii) African, (iv) American, and (v) Dry forests. Our results do not support the traditional neo- versus paleotropical forest division but instead separate the combined American and African forests from their Indo-Pacific counterparts. We also find indications for the existence of a global dry forest region, with representatives in America, Africa, Madagascar, and India. Additionally, a northern-hemisphere Subtropical forest region was identified with representatives in Asia and America, providing support for a link between Asian and American northern-hemisphere forests.