Temporal and spatial regulation of bone morphogenetic protein signaling in late lung development.

Bone morphogenetic proteins (BMPs) play important roles in early lung development. No study to date has addressed a role for BMP signaling in late lung development. We describe changes in the expression and localization of BMP receptors (Bmpr1a, Bmpr1b, and Bmpr2) and Smad (Smad1, Smad4, Smad5, and Smad8) intracellular signaling proteins during the saccular and alveolarization stages of late lung development. BMP signaling, assessed by Smad1/5 phosphorylation, nuclear translocation, and induction of id1, id2, and id3 gene expression, was evident throughout late lung development. Our data indicate that BMP signaling is active during late lung development, and points to roles for the BMP system in septal and vascular development, and in the homeostasis of the epithelial layer of large conducting airways in the mature lung.     

Regulation of human basophil adhesion to endothelium under flow conditions: Different very late antigen 4 regulation on umbilical cord blood-derived and peripheral blood basophils

BACKGROUND: Although soluble mediators released by basophils in tissue sites contribute to the chronic injury that occurs in hypersensitivity diseases, only limited information is available about how circulating basophils are recruited to tissues. In particular, the interaction of basophils with endothelium under conditions that mimic physiologic flow has not been explored. OBJECTIVE: We sought to identify adhesion molecules regulating the attachment of human basophils to IL-4-activated human umbilical vein endothelial cells (HUVECs) under flow conditions. METHODS: A parallel-plate flow chamber and blocking mAbs were used to define the adhesion molecules involved in the interactions of peripheral blood basophils (PBBs) and cord blood-derived basophils (CBDBs) with IL-4-activated HUVECs and with Chinese hamster ovary (CHO) cell transfectants expressing specific adhesion molecules. A fluorescent ligand specific for very late antigen 4 (VLA-4) was used to directly examine the VLA-4 affinity state of basophils. RESULTS: Flowing PBBs and CBDBs attached to activated HUVECs and to CHO cells expressing P- or E-selectin. However, only CBDBs attached to vascular cell adhesion molecule 1 (VCAM-1)-transfected CHO cells under flow conditions. The attachment of CBDBs to CHO cells was blocked by mAbs directed against E-selectin, P-selectin, and VCAM-1, whereas attachment of PBBs was blocked by E-selectin and P-selectin mAbs. Activating VLA-4 with Mn(2+) on PBBs resulted in adhesion to the VCAM-1-transfected CHO cells, indicating that VLA-4 activity on PBBs can be regulated, at least in part, through affinity changes. The Mn(2+)-induced upregulation of basophil VLA-4 affinity was demonstrated directly by using a fluorescent ligand for VLA-4 and flow cytometry. CONCLUSIONS: The interaction of human CBDBs and PBBs with endothelium under flow conditions is mediated in part by both P- and E-selectin. VLA-4 additionally contributes to the adhesion of flowing CBDBs. However, the affinity of VLA-4 is too low to support the adhesion under flow conditions of unstimulated PBBs.     

Thermal gradients in microtitration plates. Effects on enzyme-linked immunoassay

Temperature studies of microtitration plates demonstrate that the use of a common bacteriology incubator for heating the plates can cause a phase lag of over 30 min for the fluid in the wells to reach 37°C from ambient temperature, and that a temperature gradient of as much as 1.6°C can exist between the peripheral and center wells. This gradient is a cause of the ‘rim’ or edge effect noted in enzyme immunoassay using microtitration plates. The problem is corrected by the use of a specially designed forced air microtitration plate incubator.     

Role of Der p 1–specific B cells in immune tolerance during 2 years of house dust mite–specific immunotherapy

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Evaluation of hyperforin analogues for inhibition of 5-lipoxygenase

The acylphloroglucinol hyperforin, a constituent of the herb Hypericum perforatum (St. John's wort), was recently identified as potent and direct inhibitor of 5-lipoxygenase (5-LO), the key enzyme in the biosynthesis of proinflammatory leukotrienes. In this study, naturally occurring analogues of hyperforin, isolated from H. perforatum, as well as a series of synthetic derivatives obtained by chemical modification of hyperforin by acylation, alkylation or oxidation, were analysed for the inhibition of 5-LO. The efficacies of these compounds were evaluated in intact human polymorphonuclear leukocytes, but also the inhibitory effects on isolated recombinant human 5-LO were investigated. Our data show that some of the oxidised hyperforin derivatives possess even improved efficacy, whereas alkylation and acylation have detrimental effects.     

Homozygous microdeletion of chromosome 4q11-q12 causes severe limb-girdle muscular dystrophy type 2E with joint hyperlaxity and contractures

Microdeletion syndromes are commonly transmitted as dominant traits and are frequently associated with variably expressed pleiotropic phenotypes. Nonlethal homozygous microdeletions, on the other hand, are very rare. Here, we delineate the fifth and so far largest homozygous microdeletion in nonmalignancies of approximately 400 kb on chromosome 4q11-q12 in a large consanguineous East-Anatolian family with six affected patients. The deleted region contains the beta-sarcoglycan gene (SGCB), the predicted gene SPATA18 (spermatogenesis associated 18 homolog) and several expressed sequence tags. Patients presented with a severe and progressive Duchenne-like muscular dystrophy phenotype, a combination of hyperlaxity and joint contractures, chest pain, palpitations, and dyspnea.     

Phenotype delineation of ZNF462 related syndrome

Zinc finger protein 462 (ZNF462) is a relatively newly discovered vertebrate specific protein with known critical roles in embryonic development in animal models. Two case reports and a case series study have described the phenotype of 10 individuals with ZNF462 loss of function variants. Herein, we present 14 new individuals with loss of function variants to the previous studies to delineate the syndrome of loss of function in ZNF462. Collectively, these 24 individuals present with recurring phenotypes that define a multiple congenital anomaly syndrome. Most have some form of developmental delay (79%) and a minority has autism spectrum disorder (33%). Characteristic facial features include ptosis (83%), down slanting palpebral fissures (58%), exaggerated Cupid's bow/wide philtrum (54%), and arched eyebrows (50%). Metopic ridging or craniosynostosis was found in a third of study participants and feeding problems in half. Other phenotype characteristics include dysgenesis of the corpus callosum in 25% of individuals, hypotonia in half, and structural heart defects in 21%. Using facial analysis technology, a computer algorithm applying deep learning was able to accurately differentiate individuals with ZNF462 loss of function variants from individuals with Noonan syndrome and healthy controls. In summary, we describe a multiple congenital anomaly syndrome associated with haploinsufficiency of ZNF462 that has distinct clinical characteristics and facial features.     

Siderophore production by Vibrio vulnificus

Previous studies in our laboratory, as well as clinical evidence, have suggested that increased iron levels in the host may be important in infections caused by the halophilic pathogen Vibrio vulnificus. To study iron acquisition, we induced siderophore production by growth in a low-iron medium, and biochemical testing indicated the production of both hydroxamate- and phenolate-type siderophores. The siderophores were extracted from growth filtrates with ethyl acetate (for phenolates) and phenol-chloroform-ether (for hydroxamates). These extracts enhanced the growth of V. vulnificus when the bacterium was grown in iron-limited medium. The ability of these siderophores to stimulate the growth of Salmonella typhimurium LT-2 enb-7 (a mutant deficient in the biosynthesis of enterochelin) and Arthrobacter flavescens JG-9 (a hydroxamate auxotroph) supported the conclusion that V. vulnificus produces both hydroxamate- and phenolate-type siderophores.