Development and standardization of an enzyme-linked inmunosorbent for the detection of orthohantavirus infection in Argentina based on its bacterial-expressed nucleocapside protein.

We conducted a development and standardization of an IgG ELISA assay for serological detection of human orthohantavirus infections using the recombinant antigen rLECH13 produced in bacterial and derived from the LECHV. The evaluation and standardization were carried out by analyzing serum samples from a total of 50 patients with confirmed Hantavirus Pulmonary Syndrome (HPS) diagnosis through the reference technique, 50 negative sera, and 53 patients with other medical conditions. The data from the assay analysis showed a diagnostic sensitivity value of 95% and a diagnostic specificity of 80%. The high sensitivity of this novel assay leads us to conclude that rLECH13 is a feasible option for use in the immunodiagnostic of orthohantavirus infection. Additionally, it is crucial to have an antigen that can be produced under conditions that do not require highly complex laboratories. Furthermore, the new assay is cost-effective, reproducible, and demonstrates excellent performance.

Human hydatid disease in Peru is basically restricted to Echinococcus granulosus genotype G1.

A molecular PCR study using DNA from 21 hydatid cysts was performed to determine which strain type is responsible for human infection in Peru. The mitochondrial cytochrome c oxidase subunit 1 (CO1) gene was amplified in 20 out of 21 samples, revealing that all but 1 sample (19/20, 95%) belonged to the common sheep strain (G1). The remaining samples belonged to the camel strain (G6). The G1 genotype was most frequently found in human cases of cystic hydatid disease (CHD) in Peru. Local control measures should focus primarily on decreasing dog and sheep infection rather than intermediate reservoirs.

Identification and intra-specific variability analysis of secreted and membrane-bound proteins from Echinococcus granulosus.

Echinococcus granulosus, the etiological agent of cystic hydatid disease, exists as a series of strains or genotypes, differing in biological features. Many of the secreted and membrane-bound proteins (S/M) from helminth parasites are involved in the host-parasite interplay and constitute potential targets for diagnosis, anti-parasitic drugs and vaccines. A number of E. granulosus S/M proteins were identified using the signal sequence trap technique. Six out of seven cDNA fragments of these newly identified proteins showed nucleotide and amino acid sequence variation. Inter-strain variation was reported for other characterized S/M proteins as the vaccine target EG95 and the major hydatid cyst fluid antigen, Antigen B (AgB). AgB is highly polymorphic, 101 different sequences related to AgB were reported so far and were grouped in 5 genes (EgB1-EgB5) and one pseudogene (EgB2p) exclusive of G5, G6/G7 genotypes. The significance of AgB polymorphism and possible consequences in diagnostic performance are discussed. The diagnostic value of the new protein variants detected in E. granulosus strains could be determined through standardized inter-laboratory studies as the recently done by the South American Network for Hydatid Serology.

Early manifestations of testicular dysgenesis in children: pathological phenotypes, karyotype correlations and precursor stages of tumour development.

Testicular dysgenesis derives from abnormal gonadal development caused by chromosome aberrations/mosaicisms or mutations/deletions in SRY or other genes responsible for testicular differentiation. Dysgenetic male pseudohaermaphroditism has bilateral dysgenetic testes characterized by a cortical network of anastomosing seminiferous cords that penetrate a thin albuginea. In asymmetric gonadal differentiation (or Mixed Gonadal Dysgenesis) a dysgenetic testis associates with a streak gonad with primitive sex cords embedded in an ovarian-like stroma. Uni- or bilateral ovotestes identify true haermaphroditism. Fluorescent in situ hybridisation studies demonstrate that the sex chromosomes of mosaic patients do not distribute homogeneously in asymmetric gonads. 45,X lines predominate over 46,XY in streak gonads, while the relationship between these two is more equivalent in dysgenetic testes, suggesting that testicular or streak differentiation is related to the balance between X0 and XY lines. Testicular dys-genesis is more severe when there is a frank predominance of X0 or XX cells. Higher percentages of XY cells coincide with lesser degrees of dysgenesis. DNA densitometry indicate a higher incidence of neoplastic transformation than previously anticipated. Various specimens showed clear aneuploid histograms but no clear indication of a cytological CIS phenotype. There was a wide cytological variation in aneuploid germ cells, ranging from normally looking big infantile spermatogonia to gonocyte/CIS cells. Aneuploidy probably precedes the full expression of the CIS phenotype. In case of doubt we recommend DNA densitometry to either confirm or discard their neoplastic nature. The earliest recognizable change in germ cell tumorigenesis is probably the polyploidisation of fetal germ cells, followed by the expression of the CIS phenotype in isolated germ cells scattered along infantile seminiferous tubules that later proliferate to give an adult type CIS pattern.