Aplasia cutis congenita and other anomalies associated with methimazole exposure during pregnancy.

Aplasia cutis congenita (ACC) is a congenital defect consisting of a circumscribed absence of skin that usually involves the scalp. The etiology is uncertain, and several teratogenic agents such as methimazole have been involved. We report two cases of ACC and other anomalies in newborns exposed to methimazole during pregnancy.

Facial self-induced paraffinoma in an elderly woman.

A 72-year-old Caucasian woman without remarkable medical history presented with an asymptomatic bilateral periocular swelling, which had been present for 2 months. Physical examination showed symmetric indurated periocular erythematous plaques (Figure 1). Biopsy of a skin lesion revealed aggregates of vacuoles of different sizes (Figure 2) surrounded by a prominent inflammatory infiltrate constituted by macrophages, lymphocytes, neutrophils, and granulomatous foreign body reaction throughout the reticular dermis and hypodermis.

Influence of the germline sequence on the thermodynamic stability and fibrillogenicity of human lambda 6 light chains.

Light chain-associated amyloidosis is a fatal disease characterized by the aggregation and pathologic deposition of monoclonal light chain-related fragments as amyloid fibrils in organs or tissues throughout the body. Notably, it has been observed that proteins encoded by the lambda variable light chain (V(L)) gene segment 6a are invariably associated with amyloid deposition; however, the contribution of the gene to this phenomenon has not been established. In this regard, we have determined the thermodynamic stability and kinetics of in vitro fibrillogenesis of a recombinant (r) V(L) protein, designated 6aJL2, which contains the predicted sequences encoded by the 6a and JL2 germline genes.

(1)H, (13)C and (15)N resonance assignment of 6aJL2(R25G), a highly fibrillogenic lambdaVI light chain variable domain.

An allotypic variation at position 25 influences the fibrillogenicity of lambdaVI light chains, which are related to humoral immune response and have been associated with AL amyloidosis. The full resonance assignment and a preliminary structural characterization of 6aJL2(R25G) are reported.

The change of the scFv into the Fab format improves the stability and in vivo toxin neutralization capacity of recombinant antibodies.

The antigen-binding fragment (Fab) has been considered a more functionally stable version of recombinant antibodies than single chain antibody fragments (scFvs), however this intuitive consideration has not been sufficiently proven in vivo. This communication shows that three out of four specific scFvs against a scorpion toxin, with different affinities and stabilities, become neutralizing in vivo when expressed as Fabs, despite the fact that they are not neutralizing in the scFv format. A scFv fragment previously obtained from a neutralizing mouse antibody (BCF2) was used to produce three derived scFvs by directed evolution.

The Pseudomonas aeruginosa RhlA enzyme is involved in rhamnolipid and polyhydroxyalkanoate production.

Pseudomonas aeruginosa produces the biosurfactant rhamnolipid, which has several potential biotechnological applications. The synthesis of this surfactant is catalyzed by rhamnosyltransferase 1, composed of the proteins RhlA and RhlB. Here we report that RhlA plays a role not only in surfactant synthesis, but also in the production of polyhydroxyalkanoates, polymers that can be used for the synthesis of biodegradable plastics.

Citrobacter koseri in scalp folliculitis.

Gram-negative folliculitis, an uncommon condition, is most often seen in older patients who have acne and who either have received prolonged courses of antibiotic therapy or have used antibacterial cleansers that selectively inhibit gram-positive organisms. Citrobacter infections are uncommon, and dermatologists seldom encounter them. In the past, these infections occurred in hospitals, particularly in neonatal intensive care units.