Immunomodulatory Metabolites Released by the Frog-Killing Fungus Batrachochytrium dendrobatidis

Batrachochytrium dendrobatidis is a fungal pathogen in the phylum Chytridiomycota that causes the skin disease chytridiomycosis. Chytridiomycosis is considered an emerging infectious disease linked to worldwide amphibian declines and extinctions. Although amphibians have well-developed immune defenses, clearance of this pathogen from the skin is often impaired. Previously, we showed that the adaptive immune system is involved in the control of the pathogen, but B. dendrobatidis releases factors that inhibit in vitro and in vivo lymphocyte responses and induce lymphocyte apoptosis. Little is known about the nature of the inhibitory factors released by this fungus. Here, we describe the isolation and characterization of three fungal metabolites produced by B. dendrobatidis but not by the closely related nonpathogenic chytrid Homolaphlyctis polyrhiza. These metabolites are methylthioadenosine (MTA), tryptophan, and an oxidized product of tryptophan, kynurenine (Kyn). Independently, both MTA and Kyn inhibit the survival and proliferation of amphibian lymphocytes and the Jurkat human T cell leukemia cell line. However, working together, they become effective at much lower concentrations. We hypothesize that B. dendrobatidis can adapt its metabolism to release products that alter the local environment in the skin to inhibit immunity and enhance the survival of the pathogen.     

Dreidimensionale Bildakquisition zur Analyse der primären, spaltbedingten Gesichtsdeformität mit einem optoelektronischen Oberflächenscanner

Background. Anthropometric analysis of the face has been performed with direct facial measurement and photogrammetry. Both methods have disadvantages. The aim of our investigation was to create a three-dimensional image of the primary cleft nasal deformity with a video scanner and to carry out linear measurements. Material and methods. Facial plaster casts of 19 patients with uni- and bilateral cleft lip and palate before primary lip repair were scanned with digital surface photogrammetry DSP 400. The width of the nose and of the nostril floor, the distance of the alar bases, the length of the ala, and the nasal tip protrusion were measured. Results. Imaging was possible without problems in all models. Direct measurements of the model correlated well with the results of the three-dimensional image. Significant dimensional differences of the nasal parameters examined were noted, depending on the cleft type. Discussion. A video-supported surface scanner allowed immediate three-dimensional imaging of the face. The computer software analyzed the generated surface exactly. The data measured with the presented system resembled other previously published results.     

External distraction of the maxilla in patients with craniofacial dysplasia

Patients with severe maxillary hypoplasia secondary to craniofacial dysplasia present a challenge to the craniofacial surgeon. Maxillary distraction presents a promising tool to treat these patients more successfully. Fifteen patients aged 12 to 20 years with craniofacial dysplasia and maxillary retrusion were treated with two different techniques after complete Le Fort I osteotomy: one group underwent face mask protraction (2 patients), and the other group underwent rigid external distraction (13 patients). Cephalometric evaluation was performed before and after distraction. Rigid external distraction appeared to be superior to face mask protraction. Maxillary retrusion was fully corrected in this group. The path of maxillary positioning was well controlled by changing the traction force vector. Distraction osteogenesis has certainly improved treatment of these patients.     

Surgical correction of craniosynostosis in malignant osteopetrosis

In osteopetrosis, bone healing is complicated by progressive sclerosis. A 2-year-old blind boy with malignant osteopetrosis developed increased intracranial pressure secondary to craniosynostosis. Osteopetrosis had already been treated with bone marrow transplantation (BMT), and bone remodeling seemed to be restored. A craniotomy was performed. The postoperative course and bone healing were uneventful. After successful BMT, craniofacial procedures seem to be possible without a high risk for osteomyelitis.     

Genetic factors affecting the consistency and magnitude of changes in plasma cholesterol in response to dietary challenge

We examined the role of common genetic variation in determining the consistency and magnitude of change in plasma total cholesterol (TC) levels in response to two separate changes from a high-saturated (SFA) to a low-saturated/high-polyunsaturated-fat (PUFA) diet, in a group of free-living healthy men and women. Consistent responders were defined as those whose mean difference in the change in TC was within one SD of the mean for all participants, and the remainder were defined as variable responders. DNA was obtained from 55 individuals and genotype determined at the apolipoprotein (apo) B locus (signal peptide, SP), apoCIII (C1100-T) and lipoprotein lipase (LPL) gene loci (HindIII). In the 38 consistent responders, the apoBSP24 allele was significantly more common than in the 17 individuals with a variable response (0.29 vs. 0.12; p < 0.05). No other polymorphism showed a significant frequency difference between groups. In the group as a whole, the correlation between the change in TC level in response to the first and second dietary change was 0.28 (p = 0.05), but those with one or more apoB SP24 alleles and those with the apoCIII genotype CC had a significantly higher correlation than those with other genotypes (0.46 (p = 0.05) vs. 0.12 (NS) and 0.31 (p = 0.05) vs. 0.02 (NS), respectively). In the group as a whole, mean response left TC 10% higher on the SFA than on the PUFA diet, and neither apoB nor apoCIII genotypes affected the magnitude of this response. However, individuals with the LPL HindIII genotype H+ H+ had a significantly smaller change in mean TC in response to diet than those with one or more H- allele (9.3% vs. 14.4%; p = 0.03). Thus variation at the apoB and apoCIII loci affects the consistency of response to change in dietary fat content, while variation at the LPL gene locus affects magnitude of response.