Calambres musculares nocturnos / Nocturnal muscular cramps

Describe que los calambres musculares son una afección muy frecuente, cuya etiología sigue siendo discutida al igual que su tratamiento. Los calambres nocturnos, se inician en forma de fasciculaciones que paulatinamente provocan una flexión enérgica tanto del tobillo como de los dedos de los pies. Un fenómeno tan frecuente motivo de un gran número de consultas médicas y que causa un importante malestar en la población, ha merecido muy poca atención en la investigación clínica. Sus mecanismos fisiopatológicos son aún muy poco conocidos hasta el momento actual. En el presente trabajo revisamos una posible causa de producción de los calambres nocturnos como son la posición del cuello al dormir y la presencia de procesos degenerativos de la columna cervical que reducen el diámetro del conducto medular, produciendo irritación del cordón posterior medular y contracción muscular involuntaria.

Failure of a synthetic vaccine to protect Aotus lemurinus against asexual blood stages of Plasmodium falciparum.

The hybrid synthetic protein SPf(66), which contains small fragments of the 83-kD, 55-kD, 35-kD, and circumsporozoite antigens of Plasmodium falciparum, was studied to determine its protective capacity against malaria infection in Aotus lemurinus monkeys. Two groups of six monkeys each were immunized six times with this polymer, which was mixed with either Freund's adjuvant or aluminum hydroxide. Two groups of five animals each were used as controls and immunized with saline solution mixed with the same adjuvants. Neither antipeptide nor antimalarial antibodies developed after the six immunization doses. Regardless of this fact, the monkeys were challenged intravenously with 10(5) P. falciparum blood stage parasites, and the resultant parasitemia was followed daily on blood smears. Only one monkey from each of the groups immunized using Freund's adjuvant (both experimental and control) was protected. In those immunized using aluminum hydroxide, one animal was protected in the experimental group, but none were protected in the control group. Anti-parasite antibodies developed during the infection, but did not correlate with protection and failed to recognize SPf(66) peptide in an enzyme-linked immunosorbent assay. Immunization with the polymer did not boost natural antibodies present in two of the monkeys before the experiment. Low levels of gamma-interferon were produced in some animals, but were not correlated with protection.

Protection against malaria in Aotus monkeys immunized with a recombinant blood-stage antigen fused to a universal T-cell epitope: correlation of serum gamma interferon levels with protection.

The major surface antigen p190 of the human malaria parasite Plasmodium falciparum contains nonpolymorphic, immunogenic stretches of amino acids which are attractive components for a subunit vaccine against malaria. One such polypeptide, termed 190L, is contained in the 80-kDa processing product of p190, which constitutes the major coat component of mature merozoites. We report here that immunization of Aotus monkeys with 190L gives only poor protection against P. falciparum challenge. However, addition by genetic engineering of a universal T-cell epitope (CS.T3) to 190L improved immunity, and as a result three of four monkeys were protected following challenge infection with blood-stage parasites. Neither antibody against the immunizing antigens or against blood-stage parasites nor the capacity of the monkeys' sera to inhibit in vitro parasite invasion correlated with protection. However, in contrast to sera from nonprotected monkeys, sera from protected animals contained elevated levels of gamma interferon. These results suggest that gamma interferon is directly or indirectly involved in the process of asexual parasite control in vivo.