Monochorionic Diamniotic Twins with Bordering Cord Insertions: Images and Outcome

Twin pregnancy contributes to perinatal mortality, particularly monochorionic diamniotic twin pregnancy. Placental abnormalities are much more common in twin pregnancies than in singletons. In MCDA pregnancy, vascular anastomoses are always present and are accountable for severe complications such as Twin-to-Twin transfusion syndrome (TTTS). In TTTS, umbilical cords are usually inserted at a distance from each other. We present a rare type of MCDA pregnancy, TTTS gr 1 case with bordering umbilical cord insertions.

Endometrial scratching technique

Problems of female subfertility are a current challenge. Implant failure of the embryo after an assisted human reproduction technique is undesirable and unpleasant, and strategies to improve this implant rate are welcome. One of these techniques is endometrial scratching. We performed a literature review by searching in the PubMed and Cochrane databases for relevant information regarding the technique of endometrial scratching. The technique of endometrial scratching is not complex, but choosing an optimal period in the menstrual cycle seems to produce the desired effects for the successful implantation of the embryo. Pregnancy rates obtained through assisted human reproduction techniques have been improved due to endometrial scratching techniques.

Minimum invasive sentinel lymph nodes dissection in cervical, endometrial and vulvar cancers

Genital cancer in women is an ongoing challenge. A correct diagnosis together with a correct staging can lead to a favorable oncological or surgical conduct with an improvement of the prognosis. A literature review was performed to find relevant information regarding the sentinel node mapping in uterine and vulvar cancer. Different dyes are available, but the bioavailability and toxicity of green indocyanine are factors that seem to bring superiority to this tracer. Tracing the sentinel node with green indocyanine is a method that involves special equipment, but the benefits are visible.

Improving laparoscopic myomectomy outcomes

In the field of benign gynecology, laparoscopic myomectomy has clear advantages, although learning curve is longer. Our study aims to review the factors that improve the technique of laparoscopic myomectomies. For women with symptomatic fibroids who wish to maintain their fertility minimally invasive myomectomy is in most cases the best option. Therefore, laparoscopic approach is associated with shorter hospital stay, faster recovery, less postoperative pain, and reduced adhesion formation. Standardization of laparoscopic techniques could help to reduce the learning curve. The costs are higher compared with open myomectomy, but when we take into account the numerous advantages that laparoscopy has, including shorter operative time, less blood loss, shorter hospital stay and a more rapid recovery time, laparoscopy is more cost-efficient.

A multicentre evaluation of the Elecsys® HIV Duo assay

BACKGROUND

Fourth generation HIV assays, which detect both HIV p24 antigen and HIV antibodies are widely used in HIV screening. The combination of markers enables the fourth generation assays to shorten the window of detection, which is important in real-world testing scenarios. The Elecsys^® HIV Duo assay is a fourth generation assay, which provides an overall result based on both the detection of the p24 antigen and HIV antibodies, and lists the sub-results for the antibody and antigen units.

OBJECTIVES AND STUDY DESIGN

The performance of the Elecsys^® HIV Duo assay was assessed at five international centres and compared with other available fourth generation assays.

RESULTS

The specificity of the Elecsys^® HIV Duo assay in 13,328 blood donor samples was 99.87% (95% confidence interval [CI] 99.80-99.93) and was 100% (95% CI 99.63-100) in 1000 routine diagnostic samples. Sensitivity was assessed in 139 seroconversion panels; the Elecsys^® HIV Duo assay detected a greater number of positive samples/number of bleeds compared with other assays investigated. An individual analysis of those seroconversion panels also shows that the Elecsys^® HIV Duo assay compared to other fourth generation assays detected HIV up to 2 days earlier than other assays. The Elecsys^® HIV Duo assay also detected 125/130 'early seroconversion' samples assessed, which was greater than the number detected with comparator fourth generation assays.

CONCLUSION

These results indicate that the Elecsys^® HIV Duo assay is appropriate for use in the diagnosis of HIV and for screening of blood donations and is sensitive for the early detection of HIV.

A Study of the Influence of Single Needle Dialysis on the Principal Parameters of Haemodialyser Performance

The clearance and ultrafiltration characteristics of flat plate and hollow fibre hemodialysers have been established using conventional two needle dialysis and unipuncture with a Bellco BL 760 double head pump system. The results obtained are comparable with no detriment to the performance when in the unipuncture mode. Furthermore, the unipunture system used for our studies enables control of ultrafiltration to be achieved enabling the use of high flux dialysers without the need for special equipment.

IL28B genetic variation and hepatitis C virus-specific CD4(+) T-cell responses in anti-HCV-positive blood donors

Epidemiological, viral and host factors are associated with the outcome of hepatitis C virus (HCV) infection, and strong host immune responses against HCV favour viral clearance. Recently, genome-wide association studies have shown a strong correlation between single-nucleotide polymorphisms (SNPs) near the interleukin-28B (IL28B) gene and spontaneous or treatment-induced HCV clearance. We have investigated whether protective IL28B genetic variants are associated with HCV-specific T-cell responses among Spanish blood donors. The rs12979860 IL28B haplotype was determined in 69 anti-HCV-positive blood donors (21 HCV RNA negative and 48 HCV RNA positive) and 30 seronegative donors. In all cases, HCV-specific CD4(+) T-cell responses to HCV recombinant proteins (core, NS3 and NS3 helicase) were assessed by ex vivo interferon-γ ELISpot assay. The rs12979860-CC genotype was highly overrepresented in donors with spontaneous HCV clearance when compared to those with chronic infection (76.2%vs 29.2%, P < 0.001; odds ratio, 7.77; 95% confidence interval, 2.4-25.3, P < 0.001). HCV-specific CD4(+) T-cell responses were detected in 16 (76.2%) spontaneous resolvers especially towards nonstructural proteins, but with no correlation with IL28B genotype. Chronic individuals had a significantly lower overall T-cell response again irrespective of IL28B genotype. When spontaneous resolvers and chronic individuals were stratified according to their IL28B genotype, significantly stronger T-cell responses were only observed among those with non-CC haplotypes. Although the protective rs12979860 IL28B CC genotype is associated with spontaneous HCV clearance, stronger CD4(+) T-cell responses towards NS3 were only evident among those with non-CC haplotypes.

Reversal of nonstructural protein 3-specific CD4(+) T cell dysfunction in patients with persistent hepatitis C virus infection

Hepatitis C virus (HCV)-specific T cell responses are essential for HCV control, and chronic infection is characterized by functionally altered antigen-specific T cells. It has been proposed that the early inactivation of specific CD4(+) T cell responses may be involved in establishment of HCV persistence. We have investigated whether HCV-specific CD4(+) T cells dysfunction can be reversed in vitro. Nonstructural protein 3 (NS3) and core-specific CD4(+) T cells from eight chronically infected and eight spontaneously resolved HCV individuals were selected through transient CD154 (CD40 ligand) expression, and their functional profile (IFN-γ, IL-2, TNF-α, IL-10 and IL-4 production by enzyme-linked immunospot assay, cytometric bead array and intracellular cytokine staining, and proliferation by carboxy-fluorescein diacetate succinimidyl ester dilution assay) was determined both ex vivo and after in vitro expansion of sorted CD154-expressing cells in the absence of specific antigen in IL-7/IL-15-supplemented medium. Ex vivo bulk CD4(+) T cells from chronic patients expressed CD154 in most cases, albeit at lower frequencies than those of resolved patients (0.11%vs 0.41%; P = 0.01), when stimulated with NS3, but not core, although they had a markedly impaired capacity to produce IL-2 and IFN-γ. Antigen-free in vitro expansion of NS3-specific CD154(+) cells from chronic patients restored IFN-γ and IL-2 production and proliferation to levels similar to those of patients with spontaneously resolved infection. Hence, NS3-specific CD4(+) T cell response can be rescued in most chronic HCV patients by in vitro expansion in the absence of HCV-specific antigen. These results might provide a rationale for adoptive immunotherapy.

Longitudinal evaluation of the structure of replicating and circulating hepatitis C virus quasispecies in nonprogressive chronic hepatitis C patients

In previous cross-sectional studies, we demonstrated that, in most patients with chronic hepatitis C, the composition and complexity of the circulating hepatitis C virus (HCV) population do not coincide with those of the virus replicating in the liver. In the subgroup of patients with similar complexities in both compartments, the ratio of quasispecies complexity in the liver to that in serum (liver/serum complexity ratio) of paired samples correlated with disease stage. In the present study we investigated the dynamic behavior of viral population parameters in consecutive paired liver and serum samples, obtained 3 to 6 years apart, from four chronic hepatitis C patients with persistently normal transaminases and stable liver histology. We sequenced 359 clones of a genomic fragment encompassing the E2(p7)-NS2 junction, in two consecutive liver-serum sample pairs from the four patients and in four intermediate serum samples from one of the patients. The results show that the liver/serum complexity ratio is not stable but rather fluctuates widely over time. Hence, the liver/serum complexity ratio does not identify a particular group of patients but a particular state of the infecting quasispecies. Phylogenetic analysis and signature mutation patterns showed that virtually all circulating sequences originated from sequences present in the liver specimens. The overall behavior of the circulating viral quasispecies appears to originate from changes in the relative replication kinetics of the large mutant spectrum present in the infected liver.

Cessation of intensive treatment with recombinant human erythropoietin is followed by secondary anemia

Little information is available on the evolution of erythropoiesis after interruption of recombinant human erythropoietin (rHuEpo) therapy. Iron-overloaded rats received 20 daily injections of rHuEpo. During treatment, reticulocytes, soluble transferrin receptor (sTfR), and hematocrit increased progressively. This was accompanied by a substantial expansion of spleen erythropoiesis but a decrease in the bone marrow. Five weeks after treatment, rats developed a significant degree of a regenerative anemia. Erythropoietic activity, as assessed by reticulocytes, sTfR, erythroid cellularity, iron incorporation into heme, and the number of erythroid colonies, was severely depressed 3 weeks after cessation of rHuEpo. This was followed by regeneration of erythroblasts and reticulocytes at weeks 6 to 7 post-Epo, but erythroid progenitors recovered only partially by that time. The anemia was definitely corrected 2 months after cessation of rHuEpo treatment. Serum Epo levels remained elevated for several weeks, but the sensitivity of marrow erythroid precursors to Epo was preserved. No rat antibodies to rHuEpo were detected, and serum from post-Epo animals did not exert any inhibitory activity on erythropoiesis. In conclusion, after cessation of intensive rHuEpo therapy, there was a strong inhibition of erythropoietic activity with secondary anemia followed by late recovery. This was not due to antibodies or other soluble inhibitory factors, a defect in endogenous Epo production, or a loss of sensitivity to Epo. This may rather represent intrinsic erythroid marrow exhaustion, mostly at the level of erythroid progenitors but also at later stages of erythropoiesis.

Cap-Poly(A) synergy in mammalian cell-free extracts. Investigation of the requirements for poly(A)-mediated stimulation of translation initiation

The 5' cap and 3' poly(A) tail of eukaryotic mRNAs cooperate to stimulate synergistically translation initiation in vivo, a phenomenon observed to date in vitro only in translation systems containing endogenous competitor mRNAs. Here we describe nuclease-treated rabbit reticulocyte lysates and HeLa cell cytoplasmic extracts that reproduce cap-poly(A) synergy in the absence of such competitor RNAs. Extracts were rendered poly(A)-dependent by ultracentrifugation to partially deplete them of ribosomes and associated initiation factors. Under optimal conditions, values for synergy in reticulocyte lysates approached 10-fold. By using this system, we investigated the molecular mechanism of poly(A) stimulation of translation. Maximal cap-poly(A) cooperativity required the integrity of the eukaryotic initiation factor 4G-poly(A)-binding protein (eIF4G-PABP) interaction, suggesting that synergy results from mRNA circularization. In addition, polyadenylation stimulated uncapped cellular mRNA translation and that driven by the encephalomyocarditis virus internal ribosome entry segment (IRES). These effects of poly(A) were also sensitive to disruption of the eIF4G-PABP interaction, suggesting that 5'-3' end cross-talk is functionally conserved between classical mRNAs and an IRES-containing mRNA. Finally, we demonstrate that a rotaviral non-structural protein that evicts PABP from eIF4G is capable of provoking the shut-off of host cell translation seen during rotavirus infection.

Efficient translation of rotavirus mRNA requires simultaneous interaction of NSP3 with the eukaryotic translation initiation factor eIF4G and the mRNA 3' end

In contrast to the vast majority of cellular proteins, rotavirus proteins are translated from capped but nonpolyadenylated mRNAs. The viral nonstructural protein NSP3 specifically binds the 3'-end consensus sequence of viral mRNAs and interacts with the eukaryotic translation initiation factor eIF4G. Here we show that expression of NSP3 in mammalian cells allows the efficient translation of virus-like mRNA. A synergistic effect between the cap structure and the 3' end of rotavirus mRNA was observed in NSP3-expressing cells. The enhancement of viral mRNA translation by NSP3 was also observed in a rabbit reticulocyte lysate translation system supplemented with recombinant NSP3. The use of NSP3 mutants indicates that its RNA- and eIF4G-binding domains are both required to enhance the translation of viral mRNA. The results reported here show that NSP3 forms a link between viral mRNA and the cellular translation machinery and hence is a functional analogue of cellular poly(A)-binding protein.

Identification of the RNA-binding, dimerization, and eIF4GI-binding domains of rotavirus nonstructural protein NSP3

The rotavirus nonstructural protein NSP3 is a sequence-specific RNA binding protein that binds the nonpolyadenylated 3' end of the rotavirus mRNAs. NSP3 also interacts with the translation initiation factor eIF4GI and competes with the poly(A) binding protein. Deletion mutations and point mutations of NSP3 from group A rotavirus (NSP3A), expressed in Escherichia coli, indicate that the RNA binding domain lies between amino acids 4 and 149. Similar results were obtained with NSP3 from group C rotaviruses. Data also indicate that a dimer of NSP3A binds one molecule of RNA and that dimerization is necessary for strong RNA binding. The dimerization domain of NSP3 was mapped between amino acids 150 and 206 by using the yeast two-hybrid system. The eukaryotic initiation factor 4 GI subunit (eIF-4GI) binding domain of NSP3A has been mapped in the last 107 amino acids of its C terminus by using a pulldown assay and the yeast two-hybrid system. NSP3 is composed of two functional domains separated by a dimerization domain.

Rotavirus RNA-binding protein NSP3 interacts with eIF4GI and evicts the poly(A) binding protein from eIF4F

Most eukaryotic mRNAs contain a 5'cap structure and a 3'poly(A) sequence that synergistically increase the efficiency of translation. Rotavirus mRNAs are capped, but lack poly(A) sequences. During rotavirus infection, the viral protein NSP3A is bound to the viral mRNAs 3' end. We looked for cellular proteins that could interact with NSP3A, using the two-hybrid system in yeast. Screening a CV1 cell cDNA library allowed us to isolate a partial cDNA of the human eukaryotic initiation factor 4GI (eIF4GI). The interaction of NSP3A with eIF4GI was confirmed in rotavirus infected cells by co-immunoprecipitation and in vitro with NSP3A produced in Escherichia coli. In addition, we show that the amount of poly(A) binding protein (PABP) present in eIF4F complexes decreases during rotavirus infection, even though eIF4A and eIF4E remain unaffected. PABP is removed from the eIF4F complex after incubation in vitro with the C-terminal part of NSP3A, but not with its N-terminal part produced in E.coli. These results show that a physical link between the 5' and the 3' ends of mRNA is necessary for the efficient translation of viral mRNAs and strongly support the closed loop model for the initiation of translation. These results also suggest that NSP3A, by taking the place of PABP on eIF4GI, is responsible for the shut-off of cellular protein synthesis.

Determination of total mercury in human hair samples by cold vapor atomic absorption spectrometry

A procedure for the determination of mercury in human hair by cold-vapor atomic absorption spectrometry with a new reaction vessel was developed and evaluated. To eliminate the so-called matrix effect, calibration was carried out in an isomedium under identical operating conditions. Under these conditions, the recovery percentage of mercury from human hair digest samples using the peak height method, was 102 +/- 2.2%. The method has been used for measuring the mercury level in hair of different groups of people living in the Nantes, France area.

Quality of perinatal death registration. A study in Hainaut, Belgium

The quality of national perinatal mortality statistics was evaluated from a survey in nine maternity hospitals in Hainaut, Belgium (total births: 7862). The overall completeness of perinatal death registration was 86%. Under-registration was especially frequent in low birth weight babies. In 69% of cases, the birth weight value reported on death certificates was in exact agreement with the value in hospital records. Using detailed categories of causes, there was, in 37% of cases, agreement between the underlying cause on death certificates and the main cause identified in hospital records. Using gross categories of causes, the level of agreement was 56%. Disagreement was mostly due to the lack of specificity of the underlying cause on death certificates. The authors suggest ways to improve the quality of registration.

A study of the influence of single needle dialysis on the principal parameters of haemodialyser performance

The clearance and ultrafiltration characteristics of flat plate and hollow fibre hemodialysers have been established using conventional two needle dialysis and unipuncture with a Bellco BL 760 double head pump system. The results obtained are comparable with no detriment to the performance when in the unipuncture mode. Furthermore, the unipuncture system used for our studies enables control of ultrafiltration to be achieved enabling the use of high flux dialysers without the need for special equipment.

An in vitro comparison of capillary flow dialyzer performances on a single needle system (double headpump)

The ultrafiltration, clearance and priming characteristics of six capillary dialyzers (C-DAK 2.5 D, C-DAK 1.8 D, Tri-Ex 1, CF M 1500, N16F160 and HF 150) were studied in single needle dialysis by way of the double headpump (BL 760, Bellco Ltd). A good control of the ultrafiltration by an appropriate choice of the mean bloodcompartment pressures (Pbo) is present in all dialyzers. After correction of the clearance for ultrafiltration the clearances of urea, creatinine, sodiumiothalamate-l125 and cyanocobalamine-Co58 (vit. B 12) rise with increasing mean pressures in the bloodcompartment of all dialyzers. We assume that a better use of available surface area due to the characteristics of the double headpump such as TMP mainly influenced by Pbo pressures and other such as tidal flow are responsible for the excellent in vitro clearances of these dialyzers with this type of single needle system.