Genetic divergence between Mexican Opuntia accessions inferred by polymerase chain reaction-restriction fragment length polymorphism analysis.

Molecular methods are powerful tools in characterizing and determining relationships between plants. The aim of this study was to study genetic divergence between 103 accessions of Mexican Opuntia. To accomplish this, polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis of three chloroplast intergenic spacers (atpB-rbcL, trnL-trnF, and psbA-trnH), one chloroplast gene (ycf1), two nuclear genes (ppc and PhyC), and one mitochondrial gene (cox3) was conducted. The amplified products from all the samples had very similar molecular sizes, and there were only very small differences between the undigested PCR amplicons for all regions, with the exception of ppc. We obtained 5850 bp from the seven regions, and 136 fragments were detected with eight enzymes, 37 of which (27.2%) were polymorphic. We found that 40% of the fragments from the chloroplast regions were polymorphic, 9.8% of the bands detected in the nuclear genes were polymorphic, and 20% of the bands in the mitochondrial locus were polymorphic. trnL-trnF and psbA-trnH were the most variable regions. The Nei and Li/Dice distance was very short, and ranged from 0 to 0.12; indeed, 77 of the 103 genotypes had the same genetic profile. All the xoconostle accessions (acidic fruits) were grouped together without being separated from three genotypes of prickly pear (sweet fruits). We assume that the genetic divergence between prickly pears and xoconostles is very low, and question the number of Opuntia species currently considered in Mexico.

IgM-capture ELISA of serum samples collected from Filipino dengue patients.

Viral antigens for 4 dengue serotypes were produced in C6/36 Aedes albopictus cells. These were used as assay antigens for IgM-capture ELISA to detect IgM antibodies in sera of dengue patients from 3 hospitals in Metro Manila, Philippines. A total of 378 serum samples came from National Children's Hospital (NCH), San Lazaro Hospital (SLH), and St Luke's Medical Center (SLMC), from January to November 1995. Three hundred and four (304) out of 378 serum samples, or 80.42% showed positive IgM ELISA titer against at least one of the 4 assay antigens. Dengue type 4 (D4) antigen detected antibodies in 61.90% (234/378) of these serum samples, whereas type 1 (D1), type 3 (D3), and type 2 (D2) had detection rates of 60.05% (227/378), 50.79% (192/378) and 49.47% (187/378) respectively. Although the results show that both D1 and D4 are the most effective antigens in identifying dengue infections for this batch of samples, the use of a cocktail of antigens is still recommended. The results of this study are the basis for the IgM-capture ELISA protocol presently applied for the laboratory confirmation of dengue cases in the Philippines.

Nódulos subcutáneos como manifestación de cisticercosis diseminada / Subcutaneous nodules as manifestation of disseminated cysticercosis

RESUMEN Antecedentes: La cisticercosis es una infección parasitaria causada por la TaeniaSolium. Puede presentar una forma diseminada con compromiso sistémico. Clínicamente, la cisticercosis diseminada puede debutar con la presencia de nódulos subcutáneos. Presentamos un caso de diagnóstico de cisticercosis diseminada con la presencia de nódulos subcutáneos y síntomas respiratorios como única fuente de sospecha de enfermedad. Caso: Se presenta el caso de un paciente varón de 76 años de edad procedente de una región del Centro del Perú que acude a emergencia por hemoptisis, baja de peso y astenia de un año de evolución. Presentaba además nódulos subcutáneos no dolorosos, móviles en miembros superiores, inferiores, tórax, abdomen, cuello y cara. En la biopsia se demostró la presencia de cisticercocelullosae. Fue tratado con albendazol 400mg cada 12 horas por 6 meses, con evolución favorable. Conclusión: La cisticercosis es una enfermedad prevalente en nuestro país. Su presentación diseminada, sin embargo, no es tan frecuente. El diagnóstico puede ser difícil y a veces permanecer oculto, pues la clínica varía de silente a formas graves, dependiendo del órgano afectado, que en una forma diseminada pueden ser múltiples los órganos afectados, como el caso de nuestro paciente. Se concluye que las presencias de nódulos subcutáneos deben hacernos pensar en la posibilidad de formas diseminadas de cisticercosis.

ABSTRACT: Cysticercosis is a parasitic infection caused by Taenia Solium. It can be present as a disseminated form with systemic compromise. Disseminated cysticercosis may clinically debut with the presence of subcutaneous nodules. We present a case of diagnosis of disseminated cysticercosis with the presence of subcutaneous nodules and respiratory symptoms as the only source of suspected disease. Case: We present the case of a 76-year-old male patient from a region of central Peru who came to emergency due to hemoptysis, low weight and asthenia of one year of evolution. It also presented subcutaneous nodules that were painless, mobile in upper and lower limbs, abdomen, neck and face, the biopsy demonstrated with the presence of cysticercuscelullosae. He was treated with albendazole 400mg every 12h for 6 months, with favorable evolution. Conclusion: Cysticercosis is a prevalent disease in our country. Its disseminated presentation, however, is not as frequent. Diagnosis can be difficult and sometimes remain hidden, as the clinic varies from silent to severe, depending on the affected organ, which in a disseminated form can be multiple, as in the case of our patient. We conclude that the presence of subcutaneous nodules should make us think about the possibility of disseminated forms of cysticercosis.