No abstract

In 1983, we isolated a porcine rotavirus (strain YM) that was prevalent in several regions of Mexico, as judged by the frequency of its characteristic electropherotype. By a focus reduction neutralization test, rotavirus YM was clearly distinguished from prototype rotavirus strains belonging to serotypes 1 (Wa), 2 (S2), 3 (SAil), 4 (ST3), 5-(OSU), and 6 (NCDV). Minor, one-way cross-neutralization (1 to 5%) was observed when antisera to the various rotavirus strains were incubated with rotavirus YM. In addition, the YM virus was not neutralized by neutralizing monoclonal antibodies with specificity to serotypes 1, 2, 3, and 5. The subgroup of the virus was determined to be I by enzyme-linked immunosorbent assay. To characterize the serotype-specific glycoprotein of the virus at the molecular level, we cloned and sequenced the gene coding for VP7. Comparison of the deduced amino acid sequence with reported homologous sequences from human and animal rotavirus strains belonging to six different serotypes further supported the distinct immunological identity of the YM VP7 protein.

Germanium (Ge) is considered a critical element due to its many industrial applications; Ge is a metalloid used in solar cells, fiber optics, metallurgy, chemotherapy, and polymerization catalysis. The main sources of Ge are sulfides ores of Zn, Pb, and Cu, coal deposits, as well as by-products and residues from the processing of these ores and coals (e.g., smelting flue dust and coal fly ashes). Indeed, over 30% of global Ge consumed come from recycling processes. The recovery of Ge from sulfide ores is mostly based on hydrometallurgical processes followed by a number of mass transfer techniques to concentrate Ge (e.g., solvent extraction). However, environmental-friendly extraction methods of Ge from coal fly ashes and copper smelting flue dust have recently been proposed in order to reduce environmental impacts. In addition, novel processes based on absorption of Ge with ribbon grass have become an interesting option not only to produce Ge but also to boost soil decontamination and biogas production. This chapter presents a general description of Ge occurrence, associations, and chemistry as well as a review of the current and novel recovery processes of Ge. The main sources of Ge and its main industrial applications are also discussed.

Leishmania mexicana causes localized and diffuse cutaneous leishmaniasis. Patients with localized cutaneous leishmaniasis (LCL) develop a benign disease, whereas patients with diffuse cutaneous leishmaniasis (DCL) suffer from a progressive disease associated with anergy of the cellular response towards Leishmania antigens. We evaluated the production of the interleukins (IL) IL-12, IL-15, IL-18 and tumour necrosis factor-alpha (TNF-alpha) and the expression of the costimulatory molecules CD40, B7-1 and B7-2 in monocytes from LCL and DCL patients, stimulated in vitro with Leishmania mexicana lipophosphoglycan (LPG) for 18 h. LCL monocytes significantly increased TNF-alpha, IL-15 and IL-18 production, and this increase was associated with reduced amounts of IL-12. DCL monocytes produced no IL-15 or IL-18 and showed a decreasing tendency of TNF-alpha and IL-12 production as the severity of the disease increased. No difference was observed in the expression of CD40 and B7-1 between both groups of patients, yet B7-2 expression was significantly augmented in DCL patients. It remains to be established if this elevated B7-2 expression in DCL patients is cause or consequence of the Th2-type immune response that characterizes these patients. These data suggest that the diminished ability of the monocytes from DCL patients to produce cell-activating innate proinflammatory cytokines when stimulated with LPG is a possible cause for disease progression.

Here we demonstrate by cross-neutralization studies that rotavirus YM is also antigenically distinct from prototype rotavirus strains of serotypes 7 (Tyl), 8 (69M), 9 (WI61), and 10 (B223). A comparison of the serotype-determining amino acid regions of the YM surface glycoprotein, VP7, with the reported homologous sequences of rotavirus strains Gottfried, 69M, B37, F45, and W161 further supported the serotypic individuality of the rotavirus YM VP7 protein.