We report 4 children with encephalitis associated with human bocavirus (HBoV) 1 or 2. All children were severely underweight, and 2 died; 1 of them had a matching HBoV2 nucleotide sequence isolated from serum and bocavirus like particles in the cerebrospinal fluid that were observed with electron microscopy. No further pathogens were detected in the cerebrospinal fluid of these patients.

This study was carried out during July 2005-June 2006, to characterize rotaviruses circulating in Bangladeshi children less than 5 years attended a peri-urban hospital. The proportion of rotavirus diarrhea was 39.5%. Genotype G2 was dominant (45.5%) followed by G1 (24.8%), G12 (9.6%), G9 (8.5%), and G4 (2.1%). G2 were mainly in combination with P[4], G1 and G9 with P[8], and G12 with P[6]. Phylogenetically Bangladeshi G1, G2, and G12 were closely related with the respective types from India, whereas Bangladeshi G9s of lineage III were with strains from Belgium and Australia. A G9 strain of lineage IV was clustered with strains from Sri Lanka and Turkey. Compared with prototype rotaviruses, Bangladeshi strains showed several amino acid substitutions at the antigenic sites of VP7. This study showed that the generation of diverse strains continued as evidenced by long G2, short G1 and G9 strains, and various combinations of G and P types.

The incidence and mortality caused by diarrhea differ among countries. The prevalence of different enteric viruses, their molecular characteristics, and infections with multiple viruses might affect the disease incidence and mortality caused by diarrhea. The objective of this study was to determine the distribution and molecular characteristics of enteric viruses in children with diarrhea in Turkey and Bangladesh. A total of 288 stool samples that were negative for group A rotavirus were collected from children aged <5 years with acute diarrhea who presented to hospitals in Turkey and Bangladesh. The samples were screened for human bocavirus (HBoV), astrovirus (HAstV), norovirus (NoV), and adenovirus (AdV). Phylogenetic analyses of the targeted virus genes were performed. In Turkey, viruses were detected in 87/150 samples (58%), which included 69 (79.3%) with single viruses and 18 (20.7%) with multiple viruses. AdV was the most common virus, followed by HBoV. In Bangladesh, viruses were detected in 123/138 samples (89.1%), which included 29 (23.6%) with single viruses and 94 (76.4%) with multiple viruses. NoV GII was the most common, followed by AdV. The dominant genotypes among the virus species were HBoV 2A, HAstV 1, NoV GI type 1, and AdV 40. For NoV GII, the Hunter variant of genotype 4 in Turkey and genotype 17 in Bangladesh were the most common among the sequenced strains. It was concluded that the distribution of the viruses associated with diarrhea in Turkish and Bangladeshi children was different. Enteric viruses and mixed infections were more prevalent in Bangladesh than in Turkey.

BackgroundRotavirus antigenemia is a common phenomenon in children with rotavirus diarrhea, but information is scarce on aspects of this phenomenon, such as genotype specificity, presence of intact viruses and correlation between genomic RNA and antigen concentration. Such information may help in understanding rotavirus pathogenesis and eventually be useful for diagnosis, treatment and prevention.Methods and findingsSerum samples were collected from children who presented at hospitals with diarrhea. Antigenemia was present in 162/250 (64.8%) samples from children with rotavirus diarrhea. No specific rotavirus genotype was found to be associated with antigenemia. Rotavirus particles could not be found by electron microscopy in concentrated serum from children with high levels of antigenemia. In passaged rotavirus suspension a significant correlation (r = 0.9559; P = 0.0029) was found between antigen level and viral copy number, but no significant correlation (r = 0.001480; P = 0.9919) was found between antigenemia level and viral copy number in serum. When intact rotavirus was treated with benzonase endonuclease, genomic double-stranded (ds) RNA was not degraded, but when sera of patients with antigenemia were treated with benzonase endonuclease, genomic dsRNA was degraded, indicating genomic dsRNA was free in sera and not inside virus capsid protein.ConclusionsAntigenemia is present in a significant number of patients with rotavirus diarrhea. Rotavirus viremia was absent in the children with rotavirus diarrhea who participated in our study, and was not indicated by the presence of antigenemia. The significance of circulating rotavirus antigen and genomic dsRNA in serum of patients with diarrhea deserves further study.

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Mixed halogen substitution on the end groups of organic photovoltaic materials has been proven to be an effective way to generate materials with enhanced performance. A systematic comparison of the mixed halogen atom types can provide comprehensive information on this strategy; however, this is usually limited by the lack of a facile synthesis route. Herein, a new class of end groups featuring mixed halogenation, easily obtained via two steps with excellent yields, is reported. The new end groups are applied in synthesizing acceptor materials, and their performance is compared in organic solar cell devices. Combined with the small molecule donor BTR‐Cl, the best‐performing acceptor BTP‐FCl‐FCl achieves a power conversion efficiency of 15.27% and a high fill factor (FF) of 75.94%. Systematic studies of the mixed halogenation analogues in devices reveal that the higher FF is consistent with the longer carrier lifetime, faster charge extraction, weaker bimolecular recombination, and is associated with the favorable BTR‐Cl:BTP‐FC1‐FC1 domain size and molecular packing, all of which are derived from the different halogen atoms. The results demonstrate that selecting suitable halogen atoms is vital in achieving high‐performance organic solar cells.

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Optimal control can be helpful to test and compare different vaccination strategies of a certain disease. This study investigates a mathematical model of HIV infections in terms of a system of nonlinear ordinary differential equations (ODEs) which describes the interactions between the human immune systems and the HIV virus. We introduce chemotherapy in an early treatment setting through a dynamic treatment and then solve for an optimal chemotherapy strategy. The aim is to obtain a new optimal chemotherapeutic strategy where an isoperimetric constraint on the chemotherapy supply plays a crucial role. We outline the steps in formulating an optimal control problem, derive optimality conditions and demonstrate numerical results of an optimal control for the model. Numerical results illustrate how such a constraint alters the optimal vaccination schedule and its effect on cell-virus interactions.