Human bocavirus (HBoV) was detected in 14 (2%) of 705 fecal specimens from Brazilian children with gastroenteritis. Coinfection with rotavirus, adenovirus, or norovirus was found in 3 (21.4%) HBoV-positive specimens. None of the HBoV-positive patients had respiratory symptoms.

Human rotavirus strains belonging to genotype G9 or P[9] were detected in a collection of stool specimens from children with diarrhea in two cities of the state of Rio de Janeiro, Brazil, between March 1997 and December 1999. G9 strains were first detected in April 1997 and remained prevalent until the end of the study, at a frequency of 15.9% (n ‫؍‬ 157). A high percentage of VP7 nucleotide (99.0 to 99.5%) and deduced amino acid identity (98.6 to 99.1%) was found between three randomly selected Brazilian G9 strains and the American G9 strain US1205. A novel G9:P[4] genotype combination was detected in addition to G9:P[8] and G9:P[6], demonstrating that this G genotype may undergo constant genetic reassortment in nature. The P[9] rotavirus strains constituted 10.2%, the majority of which were detected between April and July 1997. The RNA electrophoretic migration pattern of the G3:P[9] strains resembled that of AU-1 virus (G3:P3[9]), suggesting a genetic similarity between the Brazilian G3:P[9] strains and the Japanese virus, which is similar to a feline rotavirus genetically.Rotaviruses are the major etiologic agents of infantile diarrhea worldwide (15). Epidemiologic studies have demonstrated that rotavirus serotypes G1, G2, G3, and G4 are the mostcommon types associated with disease globally, and therefore they are the targets for vaccine development (13,15). Recently, unusual rotavirus serotypes and genotypes have been described in association with diarrhea in various parts of the world. These include serotype G5 in Brazil (9, 17); G8 in Malawi (5), Kenya (21), South Africa (34), the United Kingdom (34), Nigeria (1), and Australia (24); and G9 in India (27), the United Sates (28), Bangladesh (36), Malawi (5), the United Kingdom, (4), Australia (25), France (2), and Ireland (22). The P specificity of a rotavirus is usually more conservative than its G specificity; P1A[8] is the most common serotype detected worldwide, followed by P1B[4] and P2A[6] (13). A rotavirus strain belonging to serotype P3 [9] was first identified in Japan and was demonstrated to be closely related to feline rotavirus strains genetically (20,35). The P[9] rotavirus strains have been detected more often in Japan (14, 37) than in other parts of the world such as Venezuela (32), Italy (32), Malaysia (29), Brazil (17), Israel (31), South Africa (33), Guinea-Bissau (7), and the United States (12). The P [9] isolates are most commonly associated with either G1 (K8-like) or G3 (AU-1-like) serotypes, except for one isolate from Guinea-Bissau which bears a G4 specificity (7).One hundred fifty-seven (23%; n ϭ 678) rotavirus-positive stool samples from children under 5 years of age with acute diarrhea (32 inpatients and 646 outpatients) were collected between March 1997 and December 1999, at four centers in the city of Rio de Janeiro, Brazil, and one center in the neighboring city of Niterói in the state of Rio de Janeiro. The five centers are located in areas of distinct levels of sanitation and socioeconomic backgrounds. The presence of rotavir...

This study reports the detection and genetic characterization of HBoV3 and HBoV2 in the stool of Brazilian patients with acute diarrhea. This is the first description of HBoV3 outside Australia, suggesting a wide global distribution of this virus. Further studies are needed to better understand the role of HBoV in gastrointestinal infections, particularly among patients with HIV/AIDS.

After tissue homogenization, 43% of the total hexokinase activity found in maize radicles was recovered in the mitochondrial fraction and 35% was soluble, in the cytosol. The maize submitochondrial particles obtained after mitochondrial sonication retained a high hexokinase activity. The mitochondrial respiration (state 4 rate) was activated by glucose. This activation was blocked by carboxyatractyloside (0.5 mM) and by oligomycin (2 micrograms/ml). The affinities for ATP and glucose of both soluble and membrane-bound maize hexokinases are similar to those of yeast hexokinase. The Km for ATP of these different forms of hexokinase varied between 0.15 and 0.37 mM, and the Km for glucose between 0.05 and 0.13 mM. A major difference between the two maize hexokinase forms is that only the mitochondrial enzyme was strongly inhibited by ADP (Ki 0.04 mM). The soluble forms of hexokinase found both in the cytosol of maize radicles and in yeast are not inhibited by ADP. In a previous report [de Meis, Grieco and Galina (1992) FEBS Lett. 308, 197-201] it was shown that the mitochondrial F1-F0-ATPase can use glucose 6-phosphate and yeast hexokinase as an ATP regenerating system. We now show that the membrane-bound hexokinase and glucose 6-phosphate can also serve as an ATP regenerating system for the mitochondria of maize radicles provided that the ADP concentration is kept below 0.05 mM. Higher ADP concentrations inhibit the reverse reaction of the mitochondrial hexokinase.

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Rotaviruses are the single most important etiologic agents of severe diarrhea of infants and young children worldwide. Surveillance of rotavirus serotypes/genotypes (both VP7[G] and VP4[P]) is in progress globally in which polymerase chain reaction (PCR) has been the assay of choice. We investigated polymorphism of the VP7 gene of serotype G9 rotavirus strains and its impact on the determination of VP7 gene genotype by PCR assay. By VP7 gene sequence analysis, we and others have previously shown that the G9 rotavirus strains belong to one of three VP7 gene lineages. By PCR assay using three different sets of commonly used primers specific for G1-4, 8 and 9, 23 Brazilian G9 strains and 5 well-characterized prototype G9 strains which collectively represented all three VP7 gene lineages were typed as: (i) G3; (ii) G4; (iii) G9; (iv) G3 and G9; or (v) G9 and G4 depending on a primer pool employed. This phenomenon appeared to be due to: (i) a VP7 gene lineage-specific polymorphism, more specifically mutation(s) in the primer binding region of the VP7 gene of G9 strain; and (ii) the magnitude of difference in nucleotide homology at respective primer binding site between homotypic (G9) and heterotypic (G3 or G4) primers present in a primer pool employed.

Rotaviruses, which are members of the Reoviridae family, are classified into seven groups (rotaviruses A to G). A complete virus particle possesses 11 double-stranded RNA segments surrounded by three concentric protein layers. Since their first detection 3 decades ago, group A rotaviruses have been established as the major cause of severe acute gastroenteritis in infants and young children in both developed and developing countries and are estimated to cause 800,000 or more deaths annually among children Ͻ5 years of age in the developing countries (22). The development of a safe and effective rotavirus vaccine has thus been a global public health goal. Extensive epidemiological studies worldwide have demonstrated that genotypes G1P[8], G2P[4], G3P [8], and G4P[8] are responsible for the majority of rotavirus infections (13,32). Thus, most of the candidate rotavirus vaccines developed so far are designed to cover G and/or P serotypes of epidemiologic importance (22). Recently, rotaviruses bearing G9P[8] or G9P[6] specificity have emerged as globally important (1,2,3,5,9,18,26,29,31,33,34,38,41,42). There are also indications that in Brazil rotavirus genotype G5P[8] may be of epidemiologic importance (17).

During 1998–2005, we analyzed stool samples from 289 children in Rio de Janeiro to detect and genotype norovirus strains. Previous tests showed all samples to be negative for rotavirus and adenovirus. Of 42 (14.5%) norovirus-positive specimens, 20 (47.6%) were identified as genogroup GI and 22 (52.3%) as GII.