Small body size of pseudoscorpions and a distinct architecture of the ovary: A step to miniaturization?

Chelicerata, the second largest subphylum of Arthropoda, includes invertebrates with a wide range of body size. Pseudoscorpions are among small or miniature chelicerates which exhibit several morphological, anatomical, and developmental features related to miniaturization, e.g., replacement of book lungs by tracheae, unpaired gonads, and matrotrophic development of the embryos outside the female body, in the brood sac. In this paper, we show the ovary structure of two pseudoscorpion species, Cheiridium museorum and Apocheiridium ferum (Cheiridiidae). Both cheiridiids are one of the smallest pseudoscorpions. The results of our observations conducted in light, transmission electron, and confocal microscopy demonstrate that the ovary of C. museorum and A. ferum, displays a significant structural difference that is unusual for chelicerates. The difference concerns the spatially restricted position of the germarium. We show that such ovary architecture results in a significantly reduced number of growing oocytes and in consequence a reduced number of deposited eggs. A centrally located germarium implies also a modified pattern of ovary development during oocyte growth due to long distance migration of the germline and the accompanying somatic cells. Herein, we postulate that such an ovary structure is related to the pseudoscorpion's small body size and it is a step towards miniaturization in the smaller pseudoscorpions species.     

Eczema herpeticum in atopic dermatitis

Atopic dermatitis (AD) is one of the most common chronic inflammatory skin diseases leading to pruritic skin lesions. A subset of AD patients exhibits a disseminated severe HSV infection called eczema herpeticum (EH) that can cause life-threatening complications. This review gives an overview of the clinical picture, and characteristics of the patients as well as the diagnosis and therapy of EH. A special focus lies on the pathophysiological hallmarks identified so far that predispose for EH. This aspect covers genetic aberrations, immunological changes, and environmental influences displaying a complex multifactorial situation, which is not completely understood. Type 2 skewing of virus-specific T cells in ADEH⁺ patients has been implicated in immune profile abnormalities, along with impaired functions of dendritic cells and natural killer cells. Furthermore, aberrations in interferon pathway-related genes such as IFNG and IFNGR1 have been identified to increase the risk of EH. IL-4, IL-25, and thymic stromal lymphopoietin (TSLP) are overexpressed in EH, whereas antimicrobial peptides like human β-defensins and LL-37 are reduced. Concerning the epidermal barrier, single nucleotide polymorphisms (SNPs) in skin barrier proteins such as filaggrin were identified in ADEH⁺ patients. A dysbalance of the skin microbiome also contributes to EH due to an increase of Staphylococcus aureus, which provides a supporting role to the viral infection via secreted toxins such as α-toxin. The risk of EH is reduced in AD patients treated with dupilumab. Further research is needed to identify and specifically target risk factors for EH in AD patients.     

Prosthetic reconstruction of a patient with an irradiated total rhinectomy with navigated surgical placement of a single zygomatic implant: A clinical report

This clinical report details the rehabilitation of a patient who underwent a total rhinectomy, subsequent adjuvant radiation therapy, and eventual prosthetic rehabilitation but then developed an empirically diagnosed medical adhesive intolerance. With the aid of digital planning and real time navigation, 2 zygomatic implants were placed by using a flapless surgical approach followed by early delivery of an interim prosthesis. In spite of the failure of 1 craniofacial implant, definitive restoration was accomplished by using a titanium bar, double magnetic attachments, and a new silicone prosthesis.     

Antigenic implications of human immunodeficiency virus type 1 envelope quaternary structure: oligomer-specific and -sensitive monoclonal antibodies.

A majority of monoclonal antibodies (mAbs) raised against soluble oligomeric human immunodeficiency virus type 1 isolate IIIB (HIV-1IIIB) envelope (env) glycoprotein reacted with conformational epitopes within the gp120 or gp41 subunits. Of 35 mAbs directed against gp41, 21 preferentially reacted with oligomeric env. A subset of these mAbs reacted only with env oligomers (oligomer-specific mAbs). In contrast, only 1 of 27 mAbs directed against the gp120 subunit reacted more strongly with env oligomers than with monomers, and none were oligomer-specific. However, 50% of anti-gp120 mAbs preferentially recognized monomeric env, suggesting that some epitopes in gp120 are partially masked or altered by intersubunit contacts in the native env oligomer. Two mAbs to oligomer-dependent epitopes in gp41 neutralized HIV-1IIIB and HIV-1SF2, and binding of these mAbs to env was blocked by preincubation with HIV-1-positive human serum. Thus, immunization with soluble, oligomeric env elicits antibodies to conserved, conformational epitopes including a newly defined class of neutralizing antibodies that bind to oligomer-specific epitopes in gp41, and may also minimize the production of antibodies that preferentially react with monomeric env protein.     

Oral activity of ether lipid ester prodrugs of cidofovir against experimental human cytomegalovirus infection

Infection with human cytomegalovirus (HCMV) can cause serious complications in bone-marrow and solid-organ transplant recipients, and current therapies are not optimal. We evaluated 2 orally active ether lipid ester analogues of cidofovir (CDV)--hexadecyloxypropyl-CDV (HDP-CDV) and octadecyloxyethyl-CVD (ODE-CDV)--in severe combined immunodeficient mice in which either human fetal retinal tissue or human fetal thymus and liver tissue had been implanted and was later infected with HCMV. Our results indicate that orally administered treatment with either HDP-CDV or ODE-CDV is 4-8-fold more active, on a molar basis, than is intraperitoneally administered CDV. These data suggest that HDP-CDV and ODE-CDV should be further evaluated as potential antiviral agents for treatment of HCMV infection.     

The yeast peptide-methionine sulfoxide reductase functions as an antioxidant in vivo

A gene homologous to methionine sulfoxide reductase (msrA) was identified as the predicted ORF (cosmid 9379) in chromosome V of Saccharomyces cerevisiae encoding a protein of 184 amino acids. The corresponding protein has been expressed in Escherichia coli and purified to homogeneity. The recombinant yeast MsrA possessed the same substrate specificity as the other known MsrA enzymes from mammalian and bacterial cells. Interruption of the yeast gene resulted in a null mutant, ΔmsrA::URA3 strain, which totally lost its cellular MsrA activity and was shown to be more sensitive to oxidative stress in comparison to its wild-type parent strain. Furthermore, high levels of free and protein-bound methionine sulfoxide were detected in extracts of msrA mutant cells relative to their wild-type parent cells, under various oxidative stresses. These findings show that MsrA is responsible for the reduction of methionine sulfoxide in vivo as well as in vitro in eukaryotic cells. Also, the results support the proposition that MsrA possess an antioxidant function. The ability of MsrA to repair oxidative damage in vivo may be of singular importance if methionine residues serve as antioxidants.