ABSTRACT Mercury (Hg) is one of the most toxic heavy metals, and it is largely used in illegal gold extraction in Peru. We evaluated the tolerance to Hg in Paronychia microphylla Phil, Ambrosia artemisioides Willd and Croton ruizianus Müll. Arg. plants, using controlled concentrations (5, 10 and 80 mg Hg L-1). Two groups were identified according to the antioxidant enzymatic and bioaccumulation response, but the changes in the soluble protein suggest other tolerance mechanisms in the species. P. microphylla has an accumulator performance (BCF = 1.16 at 10 mg Hg L-1); in contrast, C. ruizianus has a exclusor behavior with low BCF and better antioxidant response. In that sense, the concentration of 5 mg Hg L-1 triggers the oxidative stress and increases the levels of malondialdehyde and proline, but when treatment concentration increases there is regulation in the antioxidant system. Among the three species, C. ruizianus Müll. Arg. has the better antioxidant response, but the lower bioaccumulation.

RESUMEN El mercurio (Hg) es uno de los metales pesados más tóxicos y se utiliza principalmente en la extracción ilegal de oro en Perú. Se evaluó la tolerancia a Hg en en plantas de Paronychia microphylla Phil, Ambrosia artemisioides Willd y Croton ruizianus Müll. Arg., utilizando concentraciones controladas (5, 10 y 80 mg Hg L -1 ). Se identificaron dos grupos, según la respuesta antioxidante enzimática y de bioacumulación, pero los cambios en la proteína soluble sugieren otros mecanismos de tolerancia en las especies. P. microphylla tiene un desempeño acumulador (BCF = 1,16 a 10 mg Hg L-1); por el contrario, C. ruizianus tiene un comportamiento excluyente con bajo BCF y mejor respuesta antioxidante. En ese sentido, la concentración de 5 mg Hg L- 1 , desencadena estrés oxidativo y aumenta los niveles de malondialdehído y prolina, pero cuando aumenta la concentración del tratamiento hay regulación en el sistema antioxidante. Entre las tres especies, C. ruizianus Müll. Arg. tiene la mejor respuesta antioxidante, pero la menor bioacumulación.

ABSTRACT Saccharum spontaneum has been used for the development of energy cane a crop aimed to be used for the production of second-generation ethanol, or lignocellulosic ethanol. Lignin is a main challenge in the conversion of cell wall sugars into ethanol. In our studies to isolate the genes the lignin biosynthesis in S. spontaneum we have had great difficulty in RT-PCR reactions. Thus, we evaluated the effectiveness of different additives in the amplification of these genes. While COMT and CCoAOMT genes did not need any additives for other genes there was no amplification (HCT, F5H, 4CL and CCR) or the yield was very low (CAD and C4H). The application of supplementary cDNA was enough to overcome the non-specificity and low yield for C4H and C3H, while the addition of 0.04% BSA + 2% formamide was effective to amplify 4CL, CCR, F5H and CCR. HCT was amplified only by addition of 0.04% BSA + 2% formamide + 0.1 M trehalose and amplification of PAL was possible with addition of 2% of DMSO. Besides optimization of expression assays, the results show that additives can act independently or synergistically.

A síndrome do X frágil é a causa mais comum de retardo mental herdado; entretanto, é subdiagnosticada na população pediátrica. Objetivamos, neste estudo, determinar as características clínicas pré e pós-puberais mais significativas observadas entre indivíduos que apresentam a mutação no gene FMR-1, e que possam ser utilizadas como método de triagem dos pacientes que devem ser submetidos à análise molecular. A partir de protocolo clínico-laboratorial, foram analisados 104 indivíduos (92 do gênero masculino e 12 do feminino) portadores de retardo mental idiopático. 17 pacientes (14 do gênero masculino) apresentaram a mutação completa. História familiar de retardo mental e contato ocular pobre foram os achados que se mostraram associados, de forma estatisticamente significante (p<0,05), aos pacientes com a síndrome do X frágil em idade pré e pós-puberal. Os pacientes em idade pós-puberal também diferiram dos controles em relação à presença de orelhas grandes, fronte proeminente e macroorquidismo.

The fragile X syndrome (FRAXA) is the most common cause of inherited mental retardation. However, it has been frequently underdiagnosed in pediatric population. The characterization of the most significant pre and post-puberal clinical features observed among patients that are positive for the FMR-1 mutation, is useful as a screening tool for ordering the DNA test. Therefore, a screening program for FRAXA has been conducted in a sample of 104 mentally retarded individuals (92 males and 12 females), comprehending familial history and physical examination in order to determine the clinical characteristics. The molecular test for the disease was performed in all individuals. Seventeen patients (14 males) were positive for the FMR-1 mutation. Familial mental retardation and poor eye contact were the most common clinical findings with statistical significance (p<0.05) in FRAXA pre and post-puberal patients. The post-puberal patients presented, as opposed to the control group, large ears, broad forehead and macroorchidism.

Os autores descrevem dois novos casos de displasia Geleofísica em irmãos, uma doença autossômica recessiva rara do metabolismo de glicoproteínas cujo defeito básico ainda não foi determinado.

The authors describe two additional cases of Geleophysic dysplasia in siblings, which is a rare autosomal recessive disorder of glycoprotein metabolism whose basic defects remain to be determined.

Os autores descrevem um novo caso de monossomia parcial do braço longo do cromossomo 6 [46,XY,del (6)(q22 <font SIZE="3" face="Symbol">®</font> qter)]. A ocorrência de retardo psicomotor severo é esperada em função do paciente apresentar um dos maiores segmentos deletados além da banda 6q25.

The authors report an additional case of partial monosomy of the long arm of chromosome 6 [46,XY,del (6)(q22 <font SIZE="3" face="Symbol">®</font> qter)]. Our patient has a large segment beyond 6q25 deleted, then severe psychomotor retardation is expected to occur.