Soft tissue regeneration in animal models using grafts from adipose mesenchymal stem cells and peripheral blood fibrin gel.

OBJECTIVE: Our study aimed to evaluate the effect of soft tissue regeneration in nude mice using grafts made from the combination of adipocytes from fat tissue mesenchymal stem cells and fibrin gel from peripheral blood. MATERIALS AND METHODS: Mesenchymal stem cells were isolated from adipose tissue and identified according to ISCT criteria. The scaffold used was fibrin obtained from peripheral blood. The grafts in this study were generated by transferring mesenchymal stem cells onto a fibrin scaffold. Two types of grafts, the research sample (fibrin scaffold containing adipocytes differentiated from mesenchymal stem cells) and the control sample (fibrin scaffold only), were grafted under the dorsal skin of the same mouse. After each research period, samples were collected and evaluated by histological methods to observe the existence and growth of cells inside the grafts. RESULTS: The results showed that the study group's graft integrated better within the tissue when compared with the control group. In addition, the grafts in the study group showed the presence of cells with characteristic morphology of adipocytes one week after transplantation. In contrast, control samples showed dimorphous shapes and features mainly composed of non-homogenous fragments. CONCLUSIONS: These initial conclusions might be considered a first step in generating safe bio-compatible engineered grafts specifically usable in post-traumatic tissue regeneration procedures.

The extrachromosomal elements of the Naegleria genus: How little we know.

There are currently 47 characterized species in the Naegleria genus of free-living amoebae. Each amoeba has thousands of extrachromosomal elements that are closed circular structures comprised of a single ribosomal DNA (rDNA) copy and a large non-rDNA sequence. Despite the presence of putative open reading frames and introns, ribosomal RNA is the only established transcript. A single origin of DNA replication (ori) has been mapped within the non-rDNA sequence for one species (N. gruberi), a finding that strongly indicates that these episomes replicate independently of the cell's chromosomal DNA component. This article reviews that which has been published about these interesting DNA elements and by analyzing available sequence data, discusses the possibility that different phylogenetically related clusters of Naegleria species individually conserve ori structures and suggests where the rRNA promoter and termination sites may be located.

A FOXO-dependent replication checkpoint restricts proliferation of damaged cells.

DNA replication is challenged by numerous exogenous and endogenous factors that can interfere with the progression of replication forks. Substantial accumulation of single-stranded DNA during DNA replication activates the DNA replication stress checkpoint response that slows progression from S/G2 to M phase to protect genomic integrity. Whether and how mild replication stress restricts proliferation remains controversial. Here, we identify a cell cycle exit mechanism that prevents S/G2 phase arrested cells from undergoing mitosis after exposure to mild replication stress through premature activation of the anaphase promoting complex/cyclosome (APC/CCDH1). We find that replication stress causes a gradual decrease of the levels of the APC/CCDH1 inhibitor EMI1/FBXO5 through Forkhead box O (FOXO)-mediated inhibition of its transcription factor E2F1. By doing so, FOXOs limit the time during which the replication stress checkpoint is reversible and thereby play an important role in maintaining genomic stability.

Immunization in Vietnam.

Since the Expanded Program on Immunization was proposed by the World Health Organization in 1981, it has been promptly adopted by Vietnam as one of the country's national priority programs. In 1986, Vietnam achieved some remarkable goals, including polio-free status and the elimination of neonatal tetanus. At the same time, however, barriers and difficulties have also emerged. This article aims to provide an overview of both achievements and barriers to the implementation of the program and proposes some solutions.

The utility of optical coherence tomography for diagnosis of basal cell carcinoma: a quantitative review.

BACKGROUND: Optical coherence tomography (OCT) is a noninvasive near-infrared light imaging technology that can be utilized to diagnose basal cell carcinomas (BCCs) based on specific morphological features. OBJECTIVES: To conduct a quantitative review using tumour-level data from published studies to assess: (i) the in vivo diagnostic accuracy of different OCT systems; (ii) correlation between OCT features and histopathological diagnosis; and (iii) factors that impact the accuracy of tumour depth estimation. METHODS: Primary tumour-level data were extracted from published studies on the use of time-domain (TD-OCT), frequency-domain (FD-OCT) and high-definition (HD-OCT) systems for diagnosis of BCCs. Quality assessment was performed using the Newcastle-Ottawa Scale and the Cochrane Risk of Bias Tool. Sensitivity and specificity for diagnosis of BCC, prevalence of morphological features and correlation of tumour depth between OCT and histopathology were analysed. RESULTS: In total, 901 BCCs from 31 studies were included. The sensitivity and specificity were 89·3% and 60·3% overall, and were highest for FD-OCT (93·7% and 61·4%, respectively). The most prevalent morphological features were lobular pattern (80·2%, 315 of 393 tumours) and hyper-reflective peritumoral stroma (51·7%, 203 of 393). Concordance between OCT and histopathological tumour depth categories was moderate (Pearson coefficient 0·48); it was highest for tumours < 1 mm and those on the extremities. The overall bias was 0·075 mm with an agreement range from -0·88 to 1·03 mm. HD-OCT and FD-OCT were superior to TD-OCT at identifying morphological features, but not at tumour depth estimation. CONCLUSIONS: OCT is a viable tool for in vivo diagnosis of BCCs. FD-OCT and HD-OCT outperformed TD-OCT in diagnostic accuracy and detection of morphological features, but not tumour depth estimation.

Levels of understanding of the rules of correct medical usage among vietnamese pharmacy students: a cross-sectional study.

BACKGROUND: Comprehensive misunderstanding about medicine usage is often associated with high treatment risks which have led to unexpected and adverse effects or even death. Many researches assessing health literacy have been undertaken, but only in adults. This study was undertaken to evaluate the level of understanding in students of medical terms and its correlation with gender, grade and parental occupation. METHODS: A cross-sectional study was conducted from September to October 2017 with 594 students (28.6% of men and 71.4% of women) of Hanoi University of Pharmacy from freshman to fifth-year students chosen randomly. The knowledge of pharmacy students was assessed by a questionnaire including 25 medical terms. Descriptive statistics and Chi-square test were used with p < 0.05 as level of statistical significance. RESULTS: The level of understanding of students was high with most of medical terms reaching over 70% correct answers. A positive significant association between health literacy and education was found with higher knowledge demonstrated in upper years, while there was no difference among students with and without parents belonging to the medical field. Regarding the relation with gender, there was no significant correlation for most medical terms. CONCLUSIONS: Levels of understanding of medical terms in pharmacy students was high, presenting a significant association with education. This study should be extended in order to assess the level of health literacy in various populations, thereby indirect evaluating implementation of medical preventive programs.

Blocks of limited haplotype diversity revealed by high-resolution scanning of human chromosome 21.

Global patterns of human DNA sequence variation (haplotypes) defined by common single nucleotide polymorphisms (SNPs) have important implications for identifying disease associations and human traits. We have used high-density oligonucleotide arrays, in combination with somatic cell genetics, to identify a large fraction of all common human chromosome 21 SNPs and to directly observe the haplotype structure defined by these SNPs. This structure reveals blocks of limited haplotype diversity in which more than 80% of a global human sample can typically be characterized by only three common haplotypes.

Rationale for the combination of cryoablation with surgical resection of hepatic tumors.

Only 5% to 10% of metastatic and primary liver tumors are amenable to surgical resection. Hepatic cryoablation has increased the number of patients who are suitable for curative treatment. The aim of this study was to evaluate survival and intrahepatic recurrence in patients treated with cryoablation and resection. From June 1994 to July 1999, thirty-eight surgically unresectable patients underwent a total of 42 cryoablative procedures for 65 malignant hepatic lesions. Twenty patients underwent cryoablation alone, and 18 patients were treated with a combination of resection and cryoablation, with a minimum of 18 months' follow-up. The 38 patients had the following malignancies: primary hepatocellular carcinoma (n = 8) and metastases from colorectal cancer (n = 21), neuroendocrine tumors (n = 3), ovarian cancer (n = 3), leiomyosarcoma (n = 1), testicular cancer (n = 1), and endometrial cancer (n = 1). Patients were evaluated preoperatively with spiral CT scans and intraoperatively with ultrasound examinations for lesion location and cryoprobe guidance. Local recurrence was detected by CT. Major complications included bleeding in three patients and acute renal failure, transient liver insufficiency, and postoperative pneumonia in one patient each. Two patients (5%) died during the early postoperative interval; mean hospital stay was 7.1 days. Median follow-up was 28 months (range 18 to 51 months). Overall survival according to Kaplan-Meier analysis was 82%, 65%, and 54% at 12, 24, and 48 months, respectively. Forty-eight-month survival was not significantly different between those patients undergoing cryoablation alone (64%) and those treated with a combination of resection and cryoablation (42%). Disease-free survival at 45 months was 36% for patients undergoing cryoablation plus resection compared to 25% for those undergoing cryoablation alone. Local recurrences were detected at five cryosurgical sites, for a rate of 12% overall (5 of 42), 11% (2 of 18) for patients in the cryoablation plus resection group, and 12% (3 of 24) for those in the cryoablation alone group. For patients with colorectal metastases, survival was 70% at 30 months compared to 33% for hepatocellular cancer and 66% for other types of tumors. Patients with tumors larger than 5 cm or numbering more than three did not have significantly decreased survival. Cryoablation of hepatic tumors is a safe and effective treatment for some patients not amenable to resection. The combination of cryoablation and resection results in survival comparable to that achieved with cryoablation alone.

An association between Vogt-Koyanagi-Harada disease and Guillain-Barré syndrome.

PURPOSE: To describe an association between Vogt-Koyanagi-Harada disease and Guillain-Barré syndrome. METHODS: Case series, describing three patients. RESULTS: In two patients, the disorders had their onsets within 2 weeks of each other; in the third patient, Vogt-Koyanagi-Harada disease occurred after 3 months, as Guillain-Barré syndrome resolved. All three patients had bilateral panuveitis typical of Vogt-Koyanagi-Harada disease. Each also developed well-accepted manifestations of Guillain-Barré syndrome, including paresis of the lower extremities (all patients), paresis of the upper extremities (two patients), paresis of cranial nerves (two patients), areflexia (all patients), and abnormal electromyography findings (two patients). CONCLUSIONS: Vogt-Koyanagi-Harada disease may follow or occur simultaneously with Guillain-Barré syndrome. The fact that these two autoimmune disorders occur together in some patients suggest that they may share common disease mechanisms.

Tissue-specific expression of antisense and sense transcripts at the imprinted Gnas locus.

The mouse Gnas gene encodes an important signal transduction protein, the alpha subunit of the stimulatory G protein, G(s). In humans, partial deficiency of G(s)alpha, the alpha subunit of G(s), results in the hormone-resistance syndrome pseudohypoparathyroidism type 1a. The mouse Gnas (and the human GNAS1) locus is transcribed from three promoter regions. Transcripts from P1, which encode Nesp55, are derived from the maternal allele only. Transcripts from P2 encode Xlalphas and are derived only from the paternal allele, while transcripts from P3 encode the alpha subunit and are from both parental alleles. The close proximity of reciprocal imprinting suggests the presence of important putative imprinting elements in this region. In this report, we demonstrate that the reciprocal imprinting occurs in normal tissues of interspecific (Mus spretus x C57BL/6) mice. Transcripts from P1 are most abundant in CNS (pons and medulla) in contrast to the more ubiquitous expression from P2 and P3. In the P1-P2 genomic region, we have identified an antisense transcript that starts 2.2 kb upstream of the P2 exon and spans the P1 region. While the P1 transcript is derived from the maternal allele, the P1-antisense (Gnas-as) is derived only from the paternal allele in most but not all tissues. Although both the Nesp55 region and the Gnas-as transcripts are present in cerebral cortex, adrenal, and spleen, Gnas-as is abundant in some tissues in which transcription from the Nesp55 region is negligible. Furthermore, the Nesp55 region transcripts remain strictly imprinted in tissues that lack Gnas-as. Our results suggest that multiple imprinting elements, including the unique Gnas-as, regulate the allelic expression of the Nesp55 region sense transcript.

Symmetric and asymmetric DNA methylation in the human IGF2-H19 imprinted region.

The two contiguous IGF2 (human insulin-like growth factor II) and H19 genes are reciprocally imprinted in both human and mouse. In most tissues, IGF2 is transcribed only from the paternal chromosome while H19 is transcribed only from the maternal allele. The presence of a differential methylation region (DMR) on the two parental alleles at the 5' flanking region of H19 has been proposed to constitute the gametic imprint, which controls the reciprocal allelic expression of the two genes. Using bisulfite genomic sequencing, we have assessed the methylation status of cytosine (including 154 CpG sites) in six CpG-rich regions of the human IGF2-H19 genes. In a CpG island near promoter P3 of the IGF2 gene, more than 99.8% of all cytosines were converted to thymidine by sodium bisulfite mutagenesis, indicating that none of the CpGs was methylated. In the IGF2 exon 8-9 region, mosaic methylation of 56 CpG sites was observed in fetal tissues and in adult blood DNA. In contrast to the mosaic methylation of IGF2, the allelic methylation of the human H19 DMR was uniform. In the CpG region located 2 kb upstream (-2362 to -1911) of the H19 transcription site, all 25 CpG sites were completely methylated on only one parental allele. Uniform allele-specific methylation was also observed in the CpG island proximal to the H19 promoter (-711 to -290) with complete methylation of all 25 CpG sites in one parental allele. In contrast, the CpG region in the H19 promoter (-292 to +15) was mosaically methylated in all tissues. In addition, cytosine was methylated at three CpNpG and GpNpC sites on the top DNA strand and one CpNpG site on the bottom DNA strand from the fetal brain. The cytosines at CpG sites were methylated on both DNA strands (symmetric methylation) while cytosines at the CpNpG and GpNpC sites were methylated on only one DNA strand (asymmetric methylation). The asymmetric methylation was associated with tissue-specific disruption of H19 genomic imprinting in fetal brain.

[Hematopoietic recovery as a function of the number of autografted CD34+ cells: a retrospective study of 66 patients with malignant hematologic diseases]. / Reprise Hématopoïétique en fonction du nombre de cellules CD34+ autogreffées: étude rétrospective chez 66 patients atteints d'hémopathies malignes.

Engraftment in relation to infused CD34+ cell number was retrospectively analysed in 66 patients with hematological diseases: non-Hodgkin's lymphoma (n = 33), multiple myeloma (n = 21), acute myelogenous leukemia (n = 7), Hodgkin's disease (n = 4) and myelodysplastic syndrome (n = 1). Progenitor cells were mobilized with rhG-CSF, alone or in association with chemotherapy. The cells were harvested by leukapheresis until at least 2 x 10(6) CD34+/kg body weight were obtained. A total of 194 leukaphereses were performed (median = 3 per patient, range 1-9). A median of 3.40 x 10(8) nucleated cells/kg (range 0.31-27.59) and a median of 7.15 x 10(6) CD34+ cell/kg (range 1.31-115.70) were transplanted. Regardless of transfusional support or patient diagnosis, engraftment was rapid in patients who had received > or = 5 x 10(6) CD34+ cell/kg. In this case, absolute neutrophil blood count > or = 0.5 x 10(9)/l was obtained on day 12 post graft (range 7-19) and platelet count > or = 20 x 10(9)/l was also reached after the same median time interval (range 8-121). From the present results, a minimal threshold of 5 x 10(6) CD34+ cell/kg appears to be suitable for providing rapid and complete hematopoieitc reconstitution in patients exposed to high doses of chemotherapy with or without total body irradiation. Furthermore, administration of rhG-CSF during post-graft period significantly decreased the neutrophil time recovery (P = 0.002) but not that of platelets (P > 0.05).

Basolateral amygdala noradrenergic influence enables enhancement of memory consolidation induced by hippocampal glucocorticoid receptor activation.

Previously, we reported that bilateral excitotoxic lesions of the basolateral nucleus of the amygdala (BLA) block the enhancing effects of posttraining systemic or intrahippocampal glucocorticoid administration on memory for inhibitory avoidance training. The present study further examined the basis of this permissive influence of the BLA on hippocampal memory functioning. Immediate posttraining unilateral infusions of the specific glucocorticoid receptor agonist RU 28362 (11beta,17beta-dihydroxy-6, 21-dimethyl-17alpha-pregna-4,6-trien-20-yn-3-one; 3.0, 10.0, or 30.0 ng in 0.5 microliter) administered into the dorsal hippocampus of male Sprague-Dawley rats induced dose-dependent enhancement of 48-h inhibitory avoidance retention. Infusions of the beta-adrenoceptor antagonist atenolol (0.5 microgram in 0.2 microliter) into the ipsilateral, but not the contralateral, BLA 10 min prior to training blocked the hippocampal glucocorticoid effects on memory consolidation. Infusions of the muscarinic cholinergic antagonist atropine (0.5 microgram in 0.2 microliter) into either the ipsilateral or contralateral BLA before training did not block the hippocampal glucocorticoid effects. These findings provide further evidence that beta-adrenergic activity in the BLA is essential in enabling glucocorticoid-induced modulation of memory consolidation and are consistent with the hypothesis that the BLA regulates the strength of memory consolidation in other brain structures. The ipsilateral nature of the BLA-hippocampus interaction indicates that BLA influences on hippocampal memory processes are mediated through neural pathways rather than by influences by means of the activation of peripheral stress responses.

Lack of reciprocal genomic imprinting of sense and antisense RNA of mouse insulin-like growth factor II receptor in the central nervous system.

Two models have been proposed to account for the molecular mechanism underlying genomic imprinting of the insulin-like growth factor II receptor gene (Igf2r): expression-competition and promoter DNA methylation. To examine which model best explains the regulation of Igf2r imprinting, we examined the allelic expression of endogenous Igf2r sense and antisense RNAs in mice. In peripheral tissues, Igf2r sense and antisense RNAs show a reciprocal pattern of imprinting and DNA methylation between the two parental alleles: the sense RNA is monoallelically expressed only from the maternal promoter which is unmethylated in region 1, and the antisense RNA is derived solely from the paternal promoter which is unmethylated in region 2. The paternal promoter of sense Igf2r and the maternal promoter of antisense Igf2r are hypermethylated and are transcriptionally suppressed. In CNS, the genomic imprinting of Igf2r sense and antisense RNAs is uncoupled: both parental promoters of Igf2r gene coding for sense RNA are unmethylated and are biallelically used for transcription. In contrast, antisense RNA of Igf2r is derived only from the paternal allele that is unmethylated in region 2, while the methylated maternal allele is silent. Uncoupling of genomic imprinting of Igf2r sense and antisense RNAs in CNS correlates with DNA methylation of the appropriate promoter region, thus favoring the model of DNA methylation over that of antisense as the chief regulator of Igf2r genomic imprinting.

Inhibition of junction assembly in cultured epithelial cells by hepatocyte growth factor/scatter factor is concomitant with increased stability and altered phosphorylation of the soluble junctional molecules.

Hepatocyte growth factor/scatter factor (HGF/SF) is a mesenchymally derived glycoprotein with a strong scattering effect on epithelial cells. A receptor tyrosine kinase encoded by the met proto-oncogene has been identified as the cellular receptor for HGF/SF. Following stimulation with HGF/SF, cell scattering occurs concurrent with decreased cell-cell adhesion and disassembly of junctional components. In culture, junction formation is cell-cell contact dependent and can be regulated by modulating the Ca2+ concentrations of the growth media. Decreasing the Ca2+ concentrations below 50 microM causes rapid disassembly of junctions, whereas increasing the Ca2+ concentrations to 1.8 mM induces cell-cell contact and junction assembly. Although associated with decreased cell-cell adhesion and disassembly of the junctional complex, HGF/SF-induced scattering occurs under high extracellular Ca2+ concentrations. To gain insight into the mechanisms of HGF/SF-induced scattering of epithelial cells, we have studied the effect(s) of HGF/SF on junction assembly by examining the solubility, stability, phosphorylation, and subcellular localization of the major components of the adhering junctions, plakoglobin (Pg) and E-cadherin, in Madin-Darby canine kidney (MDCK) epithelial cells and in a MDCK cell line expressing an exogenous chimeric met receptor (CSF-MET) that scatters in response to colony-stimulating factor 1 (CSF-1). The results have shown that in HGF/SF-stimulated MDCK cells, adhering junctions were not assembled upon induction of cell-cell contact. Immunofluorescence analyses showed that larger amounts of Pg and E-cadherin were Triton X-100 extractable, and more significantly, these proteins were homogeneously distributed along the membrane and were not concentrated at the areas of cell-cell contact. Similar results were obtained for CSF-MET expressing MDCK cells in response to CSF-1. In contrast, none of the above effects were detected in MDCK cells expressing a mutant CSF-MET chimera containing a phenylalanine substitution at tyrosine 1356 in met, which fails to scatter in response to CSF-1. When compared with the unstimulated cells, the inhibition of cell adhesion promoted by HGF/SF correlated with an increased stability of the newly synthesized soluble E-cadherin and Pg and an altered phosphorylation pattern of E-cadherin, as determined by partial proteolytic peptide mapping.

Human T-lymphotropic virus type II infection in Vietnamese thalassemic patients.

Anti-human T-lymphotropic virus type I/II (HTLV-I/II) antibodies were screened by particle agglutination test in a total of 66 patients with thalassemia major who received multiple transfusion from paid donors at the Blood Transfusion Hematology Center of Ho Chi Minh City in South Vietnam. HTLV-II infection was confirmed in 6 patients (9.1%) by Western blot analysis and/or polymerase chain reaction. Phylogenetic analysis revealed that long terminal repeat sequences of HTLV-II proviruses from 5 thalassemic patients in Vietnam belonged to the same phylogenetic subgroup of HTLV-IIb as those from intravenous drug abusers in North America and Europe. These data shed light on the route of introducing HTLV-II into Vietnam.

Multiple brain atlas database and atlas-based neuroimaging system.

For the purpose of developing multiple, complementary, fully labeled electronic brain atlases and an atlas-based neuroimaging system for analysis, quantification, and real-time manipulation of cerebral structures in two and three dimensions, we have digitized, enhanced, segmented, and labeled the following print brain atlases: Co-Planar Stereotaxic Atlas of the Human Brain by Talairach and Tournoux, Atlas for Stereotaxy of the Human Brain by Schaltenbrand and Wahren, Referentially Oriented Cerebral MRI Anatomy by Talairach and Tournoux, and Atlas of the Cerebral Sulci by Ono, Kubik, and Abernathey. Three-dimensional extensions of these atlases have been developed as well. All two- and three-dimensional atlases are mutually preregistered and may be interactively registered with an actual patient's data. An atlas-based neuroimaging system has been developed that provides support for reformatting, registration, visualization, navigation, image processing, and quantification of clinical data. The anatomical index contains about 1,000 structures and over 400 sulcal patterns. Several new applications of the brain atlas database also have been developed, supported by various technologies such as virtual reality, the Internet, and electronic publishing. Fusion of information from multiple atlases assists the user in comprehensively understanding brain structures and identifying and quantifying anatomical regions in clinical data. The multiple brain atlas database and atlas-based neuroimaging system have substantial potential impact in stereotactic neurosurgery and radiotherapy by assisting in visualization and real-time manipulation in three dimensions of anatomical structures, in quantitative neuroradiology by allowing interactive analysis of clinical data, in three-dimensional neuroeducation, and in brain function studies.

Human T-lymphotropic Virus Type II Infection inVietnamese Thalassemic Patients.

Anti-human T-lymphotropic virus type I/II (HTLV-I/II) antibodies were screened by particle agglutination test in a total of 66 patients with thalassemia major who received multiple transfusion from paid donors at the Blood Transfusion Hematology Center of Ho Chi Minh City in South Vietnam. HTLV-II infection was confirmed in 6 patients (9.1%) by Western blot analysis and/or polymerase chain reaction. Phylogenetic analysis revealed that long terminal repeat sequences of HTLV-II proviruses from 5 thalassemic patients in Vietnam belonged to the same phylogenetic subgroup of HTLV-IIb as those from intravenous drug abusers in North America and Europe. These data shed light on the route of introducing HTLV-II into Vietnam.