Syndrome d’Hikikomori ou de claustration à domicile : À propos d’une observation Tunisienne

Background

Hikikomori syndrome originally described in Japan as a psychosocial and cultural entity affecting especially adolescents. These younger people stop going to school or workplace and spend most of the time withdrawn into their homes for months or years. Hikikomori-like cases named under other nomenclatures such as “social withdrawal” or “housebound syndrome” have recently been reported in other countries of varying sociocultural and economic backgrounds such as Hong Kong, Oman, US, Spain and France. Thus, Hikikomori has now crossed the limits of a culture-bound phenomenon to become an increasingly prevalent international condition. In Tunisia, young people who meet the definition of “Hikikomori” are not necessarily the same as “Hikikomori” in Japan. Our objective was to illustrate a case of Hikikomori in Tunisia, as well as the diagnostic difficulties it posed.

Three cefotaximases, CTX-M-9, CTX-M-13, and CTX-M-14, among Enterobacteriaceae in the People's Republic of China

Of 15 extended-spectrum beta-lactamase (ESBL)-producing isolates of the family Enterobacteriaceae collected from the First Municipal People's Hospital of Guangzhou, in the southern part of the People's Republic of China, 9 were found to produce CTX-M ESBLs, 3 produced SHV-12, and 3 produced both CTX-M and SHV-12. Eleven isolates produced either TEM-1B or SHV-11, in addition to an ESBL. Nucleotide sequence analysis of the 12 isolates carrying bla(CTX-M) genes revealed that they harbored three different bla(CTX-M) genes, bla(CTX-M-9) (5 isolates), bla(CTX-M-13) (1 isolate), and bla(CTX-M-14) (6 isolates). These genes have 98% nucleotide homology with bla(Toho-2). The bla(CTX-M) genes were carried on plasmids that ranged in size from 35 to 150 kb. Plasmid fingerprints and pulsed-field gel electrophoresis showed the dissemination of the bla(CTX-M) genes through transfer of different antibiotic resistance plasmids to different bacteria, suggesting that these resistance determinants are highly mobile. Insertion sequence ISEcp1, found on the upstream region of these genes, may be involved in the translocation of the bla(CTX-M) genes. This is the first report of the occurrence of SHV-12 and CTX-M ESBLs in China. The presence of strains with these ESBLs shows both the evolution of bla(CTX-M) genes and their dissemination among at least three species of the family Enterobacteriaceae, Escherichia coli, Klebsiella pneumoniae, and Enterobacter cloacae, isolated within a single hospital. The predominance of CTX-M type enzymes seen in this area of China appears to be similar to that seen in South America but is different from those seen in Europe and North America, suggesting different evolutionary routes and selective pressures. A more comprehensive survey of the ESBL types from China is urgently needed.     

Association of an HLA‐G 14‐bp Insertion/Deletion polymorphism with high HBV replication in chronic hepatitis

Identification of an HLA‐G 14‐bp Insertion/Deletion (Ins/Del) polymorphism at the 3′ untranslated region of HLA‐G revealed its importance in HLA‐G mRNA stability and HLA‐G protein level variation. We evaluated the association between the HLA‐G 14‐bp Ins/Del polymorphism in patients with chronic Hepatitis B virus (HBV) infection in a case–control study. Genomic DNA was extracted from 263 patients with chronic HBV hepatitis and 246 control subjects and was examined for the HLA‐G 14‐bp Ins/Del polymorphism by PCR. The polymorphic variants were genotyped in chronic HBV seropositive cases stratified according to HBV DNA levels, fibrosis stages and in a control population. There was no statistical significant association between the 14‐bp Ins/Del polymorphism and increased susceptibility to HBV infection neither for alleles (P = 0.09) nor for genotypes (P = 0.18). The stratification of HBV patients based on HBV DNA levels revealed an association between the 14‐bp Ins/Del polymorphism and an enhanced HBV activity with high HBV DNA levels. In particular, the Ins allele was significantly associated with high HBV DNA levels (P = 0.0024, OR = 1.71, 95% CI 1.2–2.4). The genotype Ins/Ins was associated with a 2.5‐fold (95% CI, 1.29–4.88) increased risk of susceptibility to high HBV replication compared with the Del/Del and Ins/Del genotypes. This susceptibility is linked to the presence of two Ins alleles. No association was observed between the 14‐bp Ins/Del polymorphism and fibrosis stage of HBV infection. We observed an association between the 14‐bp Ins/Del polymorphism and high HBV replication characterized by high HBV DNA levels in chronic HBV patients. These results suggest a potential prognostic value for disease outcome evaluation.     

Fabrication of transferable micropatterned-co-cultured cell sheets with microcontact printing

The purpose of the present study is to develop a novel method for the fabrication of transferable micropatterned cell sheets for tissue engineering. To achieve this development, microcontact printing of fibronectin on commercially available temperature-responsive dishes was employed. Primary rat hepatocytes were seeded on the dish surfaces printed with fibronectin. Under serum-free conditions, hepatocytes were attached onto fibronectin domains selectively. Then, a second cell type of endothelial cells was seeded in the presence of serum. Double fluorescent staining revealed that endothelial cells successfully adhered to the intervals of hepatocyte domains. Finally, all the cells were harvested as a single contiguous micropatterned cell sheet upon temperature-reduction. With a cell sheet manipulator having a gelatin layer for the support of harvested cell sheets, harvested micropatterned cell sheets were transferred to new dish surfaces. This technique would be useful for the fabrication of thick tissue constructs having a complex microarchitecture.     

Hepatitis A in Tunisia: phylogenetic analysis of hepatitis A virus from 2001 to 2004

Tunisia is a highly endemic area for hepatitis A virus (HAV) infection. In the present study, the phylogenetic characterization of the VP1 gene (882 nucleotides) and of the VP1/2A junction (336 nucleotides) of Tunisian strains were examined. One hundred strains isolated from patient with anti-HAV IgM from 2001 to 2004 were amplified by RT-PCR, sequenced at the VP1 and at the VP1/2A junction and aligned with the published sequences to establish phylogenetic analysis. All Tunisian strains belong to genotype I with a greater presence of sub-genotype IA (98%) originate from most of Tunisian regions and 2% of sub-genotype IB. In addition, sub-genotype IA and IB strains formed 25 different clusters. Genetically similar strains were also identified between 2001 and 2004 isolated from the southern and the central part of Tunisia, suggesting that an indigenous strain has been circulating in the Tunisia. The genetic profile of the VP1 region showed that Tun159-02 and Tun40-03 clustered respectively in the IB and IA sub-genotype, however, analysis of VP1/2A junction revealed in contrast that Tun159-02 and Tun40-03 clustered respectively in IA and IB. This is the first report to identify sub-genotype IA in Tunisia and provides new data on the genetic relatedness of HAV from Tunisia and the distribution of sub-genotype IA in this part of the world.     

Cell sheet engineering: a unique nanotechnology for scaffold‐free tissue reconstruction with clinical applications in regenerative medicine

Cell sheet technology (CST) is based on the use of thermoresponsive polymers, poly(N‐isopropylacrylamide) (PIPAAm). The surface of PIPAAms is formulated in such a way as to make its typical thickness <100 nm. In this review, we first focus on how the methods of PIPAAm‐grafted surface preparations and functionalization are important to be able to harvest a functional cell sheet, to be further transplanted. Then, we present aspects of tissue mimics and three‐dimensional reconstruction of a tissue in vitro. Finally, we give an overview of clinical applications and clinically relevant animal experimentations of the technology, such as cardiomyopathy, visual acuity, periodonty, oesophageal ulcerations and type 1 diabetes.