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841.
842.
Background: The aim of this study is to assess the efficacy and clinical safety of regional anticoagulation (heparin pre-filter plus post-filter protamine) plus antiaggregation (pre-filter prostacyclin) [Group 1 (G1)] vs. only systemic heparin anticoagulation without antiaggregation [Group 2 (G2)] in critically ill patients with acute renal failure undergoing continuous veno-venous haemofiltration (CVVH).
Methods: One hundred and ten patients were randomized in a prospective, controlled pilot study. G1 patients received 1000 U/h pre-filter heparin, 10 mg/h post-filter protamine sulphate and 4 ng/kg/min pre-filter prostacyclin, while G2 patients received 1000 U/h pre-filter heparin. The haemofilter transmembrane pressure (TMP) and lifespan, as well as the platelet count were observed 1 h before, and at 6, 12, 18, 24 and 36 h from the beginning of CVVH.
Results: Haemofilter TMP remained unchanged in G1 while it increased up to three times in G2 ( P =0.0002). The median filter lifespan was 68 h in G1 and 19 h in G2. The rate of spontaneous circuit failure was 24% in G1 and 93% in G2 ( P =0.0001). The platelet count was stable over the treatment period in G1 while in G2 it decreased progressively ( P =0.0073).
Conclusion: In critically ill patients suffering from acute renal failure, regional anticoagulation with pre-filter heparin and post-filter protamine plus antiaggregation during CVVH is a simple and safe procedure that prevents increases in filter TMP and increases circuit life time compared with systemic anticoagulation with pre-filter heparin only.  相似文献   
843.
844.

Background  

In conjunction with the growing prevalence of obesity and the older age of pregnant women gestational diabetes (GDM) is a major health problem.  相似文献   
845.
CONTEXT: Activating mutations in the KCNJ11 gene, which encodes the Kir6.2 subunit of the pancreatic beta-cell K(ATP) channel, result in permanent and transient neonatal diabetes. The majority of KCNJ11 mutations are spontaneous, but the parental origin of these mutations is not known. OBJECTIVE: Our objective was to determine the parental origin of de novo KCNJ11 mutations and investigate the possibility of mosaicism in transmitting parents. DESIGN: We identified 68 index cases with a KCNJ11 mutation where neither parent was known to be affected. DNA was available from both parents of 41 probands. The parental origin of the mutation was determined in 18 families by examination of pedigrees, microsatellite analysis, or allele-specific PCR. RESULTS: A nonsignificant excess of paternally derived mutations was found with 13 of 18 (72%) shown to have arisen on the paternal allele. There was no evidence to suggest an association with increased age at conception. In two families, there were half-siblings with permanent neonatal diabetes born to an unaffected father, suggesting germline mosaicism that was confirmed by the presence of the R201C mutation in one father's semen. Somatic mosaicism was detected in one unaffected mother, and this mutation will also be present in her germ cells. CONCLUSION: De novo KCNJ11 mutations can arise either during gametogenesis or embryogenesis. The possibility of germline mosaicism means that future siblings are at increased risk of neonatal diabetes, and we recommend that molecular genetic testing is routinely offered at birth for subsequent siblings of children with de novo KCNJ11 mutations.  相似文献   
846.
Heterozygous activating mutations in the gene encoding for the ATP-sensitive potassium channel subunit Kir6.2 (KCNJ11) have recently been shown to be a common cause of permanent neonatal diabetes. Kir6.2 is expressed in muscle, neuron and brain as well as the pancreatic beta-cell, so patients with KCNJ11 mutations could have a neurological phenotype in addition to their diabetes. It is proposed that some patients with KCNJ11 mutations have neurological features that are part of a discrete neurological syndrome termed developmental Delay, Epilepsy and Neonatal Diabetes (DEND), but there are also neurological consequences of chronic or acute diabetes. We identified KCNJ11 mutations in four of 10 probands with permanent neonatal diabetes and one affected parent; this included the novel C166F mutation and the previously described V59M and R201H. Four of the five patients with mutations had neurological features: the patient with the C166F mutation had marked developmental delay, severe generalised epilepsy, hypotonia and muscle weakness; mild developmental delay was present in the patient with the V59M mutation; one patient with the R201H mutation had acute and chronic neurological consequences of cerebral oedema and another had diabetic neuropathy from chronic hyperglycaemia. In conclusion, the clinical features in these patients support the existence of a discrete neurological syndrome with KCNJ11 mutations. The severe DEND syndrome was seen with the novel C166F mutation and mild developmental delay with the V59M mutation. These features differ markedly from the neurological consequences of acute or chronic diabetes.  相似文献   
847.

Introduction

The aim of this study was to investigate whether in-hospital mortality was associated with the administered fraction of oxygen in inspired air (FiO2) and achieved arterial partial pressure of oxygen (PaO2).

Methods

This was a retrospective, observational study on data from the first 24 h after admission from 36,307 consecutive patients admitted to 50 Dutch intensive care units (ICUs) and treated with mechanical ventilation. Oxygenation data from all admission days were analysed in a subset of 3,322 patients in 5 ICUs.

Results

Mean PaO2 and FiO2 in the first 24 h after ICU admission were 13.2 kPa (standard deviation (SD) 6.5) and 50% (SD 20%) respectively. Mean PaO2 and FiO2 from all admission days were 12.4 kPa (SD 5.5) and 53% (SD 18). Focusing on oxygenation in the first 24 h of admission, in-hospital mortality was shown to be linearly related to FiO2 value and had a U-shaped relationship with PaO2 (both lower and higher PaO2 values were associated with a higher mortality), independent of each other and of Simplified Acute Physiology Score (SAPS) II, age, admission type, reduced Glasgow Coma Scale (GCS) score, and individual ICU. Focusing on the entire ICU stay, in-hospital mortality was independently associated with mean FiO2 during ICU stay and with the lower two quintiles of mean PaO2 value during ICU stay.

Conclusions

Actually achieved PaO2 values in ICU patients in The Netherlands are higher than generally recommended in the literature. High FiO2, and both low PaO2 and high PaO2 in the first 24 h after admission are independently associated with in-hospital mortality in ICU patients. Future research should study whether this association is causal or merely a reflection of differences in severity of illness insufficiently corrected for in the multivariate analysis.  相似文献   
848.
Analysis of IgH and TcR-γ genes using consensus primers identifying junctional regions of rearranged genes by polymerase chain reaction (PCR) was performed on tissues involved by Hodgkin's disease (HD) in 90 cases and was correlated with the immunophenotype of Hodgkin and Reed–Sternberg (HRS) cells and the presence of Epstein–Barr virus (EBV) within these cells. Clonal IgH gene rearrangements were found in 1/5 cases of lymphocyte predominance (LP) subtype and none was positive for EBV. In 85 cases of classic HD, no IgH or TcR-γ gene rearrangements were found in 51 (60 per cent) cases. A similar percentage, but not the same cases, were of null (non-B, non-T) phenotype. Of 30 cases where a B phenotype was assigned to HRS cells, nine had IgH gene rearrangements, three had TcR-γ gene rearrangements, and two had both genes rearranged. None of the five cases assigned to T phenotype of HRS cells showed rearrangement of TcR-γ genes, but two cases showed rearranged IgH genes. Among 41 cases of null phenotype, ten had IgH gene rearrangements, five had TcR-γ gene rearrangements, and three cases had both genes rearranged. Whereas EBV was detectable in HRS cells in 17/43 classic HD cases of assigned B phenotype, EBV was also detectable in 2/5 cases of assigned T phenotype and in 21 cases with the null phenotype. Furthermore, there was no correlation of EBV with the presence or lack of IgH or TCR-γ gene rearrangements. Of the remainder, half (30 per cent) expressed antigens associated with lymphocytes without an appropriate genotype. The results confirm lymphocyte-lineage committed cells at the origin of HRS cells in 40 per cent of cases. Any hypothesis of a non-lymphocytic origin of HRS cells will require the inducibility of CD30 on candidate precursors and the methodology for probing genetic events in such cells to be addressed. © 1997 by John Wiley & Sons, Ltd.  相似文献   
849.
850.
Due to the COVID-19 infection, which was recognized as a global pandemic by the WHO on March 11, 2020, the number of cases and disease-related deaths increases day by day globally. For this reason, antiviral agents used in treatment and vaccines, the most effective weapon in prevention, continue to be the most popular topic of the plan. Several situations are expected to affect the course of the pandemic. The loss of the ability of the virus to mutate and cause disease, the fact that those who become immunized by having the disease in the society reach a critical rate and create social immunity (herd immunity), and the provision of social immunity with effective vaccination can be counted as some of these situations.Candidate vaccines in the clinical phase among RNA-based vaccines: This review aimed to examine COVID-19 vaccine candidates using RNA technology and compile its current data. We used PubMed, Google Scholar, and World Health Organization (WHO) databases. Also, we followed up on the latest news and developments on vaccine companies’ websites.Conclusion: Vaccination trials, which started due to the seriousness and urgency of the situation that we are in, continue exceptionally quickly and effectively. As per the WHO›s data on July 9, 2021, there have been 291 vaccine trials, 107 of which are in the clinical phase, and 18 (16%) of the vaccine candidates in the clinical phase are RNA-based vaccines. Also, the number of RNA-based vaccines with ongoing preclinical trials is 2  相似文献   
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