[Predictive value of early lactate area for mortality in elderly patients with septic shock]

Objective: To investigate the predictive value of early lactate area for mortality in elderly patients with septic shock. Methods: From January 2012 to December 2013, a prospective study was conducted in the Department of Critical Care Medicine, Qilu Hospital of Shandong University. A total of 115 septic shock patients with age ≥65 years were included in the study. Serum lactate was measured every 6 hours, the lactate indicators, including early lactate area, APACHE Ⅱ score etc were recorded. Results: The overall 28-day mortality rate was 67.0%. The top three primary infection sources were lung, abdominal cavity and bloodstream. When compared to survivors, non-survivors had significantly elevated early lactate area and APACHE Ⅱ score and lowered lactate clearance[(27.4±7.6) vs ( 20.3±6.5)], they were significantly more likely to have undergone mechanical ventilation, renal replacement therapy and inotropic or vasopressor support for ≥3 d, and more frequently displayed signs of cardiovascular, respiratory, and renal and hepatic dysfunction (all P<0.05) .Receiver Operating Characteristic curves indicated the lactate area score displayed a strong predictive power for 28 day mortality as indicated by an AUC of 0.758 (P<0.01) and had significantly greater predictive power when compared to the initial lactate or lactate clearance (all P<0.05). Conclusions: In geriatric patients with septic shock, the early lactate area is a useful predictor for early death and showed better predictive value than other lactate indicators.

[Impacts of early metoprolol intervention on connexin 43 and phosphorylated connexin 43 expression in rabbits with experimental myocardial infarction]

Objective: To investigate the early intervention effects of metoprolol on connexin 43(Cx43) and phosphorylated Cx43 (p-Cx43) expression in rabbits with post myocardial infarction. Methods: A total of 24 adult male New Zealand white rabbits were divided into sham group (n=6), early treatment group(n=6), routine treatment group(n=6), and myocardial infarction group(n=6) with a randomized block design blocked by weight. Myocardial infarction was induced by left anterior descending coronary artery (LAD) ligation. Rabbits in sham group received similar surgical procedure without LAD ligation. Metoprolol (12.5 mg/kg dissolved in 2 ml distilled water) was applied to rabbits in early treatment group and routine treatment group per gavage immediately after recovery from anesthesia and at 24 hours after myocardial infarction, respectively, then treated daily for 40 days. Rabbits in sham group and myocardial infarction group received 2 ml distilled water per gavage daily for 40 days. Plasma lactate dehydrogenase (LDH) and creatine kinase (CK) level were detected by automatic biochemistry analyzer after 6 hours in all rabbits. Ventricular fibrillation threshold (VFT) was measured in vivo by bipolar pacing electrodes at 40 days. Cx43 and p-Cx43 distribution in ventricular tissue was detected by immunofluorescence analyses. Cx43 and p-Cx43 protein level in ventricular tissue was determined by Western blot. Results: (1) Plasma LDH ((851.7±85.9)U/L vs. (332.3±39.6)U/L, P<0.01) and CK ((1 192.7±105.3)U/L vs. (462.3±65.6)U/L, P<0.01) were significantly higher in myocardial infarction group than in sham group (both P<0.01). (2) VFT was significantly lower in myocardial infarction group than that in sham group ((470.0±91.0) beats per minute vs. (683.3±60.9) beats per minute, P<0.05), and VFT was significantly higher in early treatment group ((633.3±43.2) beats per minute) and routine treatment group ((645.0±30.8) beats per minute) than in the myocardial infarction group (both P<0.05). (3) Immunofluorescence analyses showed that Cx43 was mainly localized in the intercalated disk, which was perpendicular to the cell long axis with linear arrangement, and less lateral distribution in sham group, early treatment group and routine treatment group, which was significantly different as the case in the myocardial infarction group. The expression of p-Cx43 in myocardial infarction group was less than in sham group, which was significantly upregulated in in early treatment group and routine treatment group when compared with myocardial infarction group, and expression of p-Cx43 was significantly higher in early treatment group than in routine treatment group. (4)The p-Cx43/Cx43 ratio of protein was significantly lower in myocardial infarction group than in sham group (0.165±0.011 vs. 0.363±0.046, P<0.05), and significantly higher in early treatment group (0.720±0.063) and routine treatment group (0.364±0.030) than in myocardial infarction group (both P<0.05), and this ratio was significantly higher in early treatment group than in routine treatment group (P<0.05). Conclusion: Metoprolol treatment, especially the early metoprolol treatment (within 24 hours after LAD ligation), could significantly improve VFT by ameliorating the distribution and dephosphorylation of myocardial Cx43 in rabbits with experimental myocardial infarction.

Ultrastructure changes induced by dry film formation of a trisodium phosphate blend, antimicrobial solution

Trisodium phosphate (TSP) has been reported to have antimicrobial activity and is approved by the U.S. Department of Agriculture for use in food processing applications. A novel (U.S. Patent 6,184,198), antimicrobial solution containing a blend of TSP, sodium bicarbonate, and sodium carbonate (TSP blend) has demonstrated effective inhibition of microbial contamination in a broad spectrum of applications. This high-resolution cold field emission scanning electron microcopy (LVSEM) investigation details structural changes and dry film formation in various classes of microbes as a mechanism for antimicrobial activity of this solution. The results showed that this TSP blend solution completely inhibited the growth of pathogenic E. coli O157:H7, and Salmonella bacteria, the mold Cryptococcus, as well as a Norwalk virus surrogate-feline calicivirus. Results by LVSEM confirmed that the antimicrobial effect was induced when encapsulating the target microbes in a high lubricity film that is formed around these organisms as the solution dries. The thickness of the film was estimated to be approximately 60 nm.

Targeted RNases: a feasibility study for use in HIV gene therapy

A targeted RNase would be ideal for gene therapy of several acquired and inherited disorders. Such an RNase may be engineered to contain a ribonucleolytic domain and a specific target RNA binding domain. To demonstrate the feasibility of this approach, an RNase targeted against human immunodeficiency virus (HIV) RNA--Tev-RNase T1--was designed and tested for its use in HIV-1 gene therapy. A human CD4+ T lymphoid (MT4) cell line and human peripheral blood lymphocytes (PBLs) were transduced with retroviral vectors lacking or expressing the tevT1 gene. Expression of enzymatically functional Tev-RNase T1 protein and its lack of toxicity was demonstrated in stable MT4 transductants. Compared with control cells lacking this protein, both transduced MT4 cells and PBLs expressing Tev-RNase T1 delayed HIV-1 replication. Tev-RNase T1 was shown to act after integration, since HIV-1 proviral DNA could be detected, but the amount of HIV-1 RNA produced in MT4 cells and PBLs was significantly decreased. This study demonstrates the feasibility of a targeted RNase strategy for therapeutic use.

Co-packaging of sense and antisense RNAs: a novel strategy for blocking HIV-1 replication

Retroviral vectors were engineered to express either sense (MoTiN-TRPsie+) or sense and antisense (MoTN-TRPsie+/-) RNAs containing the human immunodeficiency virus type-1 (HIV-1) trans -activation response (TAR) element and the extended packaging (Psie) signal. The Psie signal includes the dimer linkage structure (DLS) and the Rev response element (RRE). Amphotropic vector particles were used to transduce a human CD4+ T-lymphoid (MT4) cell line. Stable transductants were then tested for sense and antisense RNA production and susceptibility to HIV-1 infection. HIV-1 production was significantly decreased in cells transduced with MoTiN-TRPsie+ and MoTN-TRPsie+/-vectors. Efficient packaging of sense and most remarkably of antisense RNA was observed within the virus progeny. Infectivity of this virus was significantly decreased in both cases, suggesting that the interfering RNAs were co-packaged with HIV-1 RNA. Vector transduction was not expected to occur and was not observed. Inhibition of HIV-1 replication was also demonstrated in human peripheral blood lymphocytes transduced with retroviral vectors expressing antisense RNA. These results suggest that (i) both sense and antisense RNAs were co-packaged with HIV-1 RNA, (ii) the co-packaged sense and antisense RNAs inhibited virus infectivity and (iii) the co-packaged sense and antisense RNAs were not transduced. Sense and antisense RNA-based strategies may also be used to co-package other interfering RNAs (e.g. ribozymes) to cleave HIV-1 virion RNA.

Co-packaging of non-vector RNAs generates replication-defective retroviral vector particles: a novel approach for blocking retrovirus replication

A Moloney murine leukemia virus (MoMuLV)-derived packaging retroviral vector, pUCMoTN-PR3, was previously developed in which the packaging (psi) signal was cloned within the 5'-long terminal repeat (LTR) U3-r and U5 sequences. The MoTN-PR3 vector particles released from a transfected packaging cell line contain RNAs with r-psi-U5 sequences at the 5'-end and U3-r sequences at the 3'-end. Upon infection, these vector particles can efficiently transduce the neomycin phosphotransferase (neo) gene to the target cells. The structure of the proviral DNA synthesized in these cells was shown to contain modified 5'- and 3'-LTRs with U3-r-psi-U5 sequences, indicating that this vector can undergo reverse transcription and integration. Analysis of psi signal-containing RNAs revealed that in addition to vector RNA transcribed from the MoMuLV 5'-LTR promoter, readthrough neo RNA transcribed from the internal herpes simplex virus (HSV) thymidine kinase (tk) promoter and cellular RNAs transcribed from the MoMuLV 3'-LTR promoter are produced. Of these, the downstream cellular RNAs are also packaged within the vector particles. These vector particles containing the vector and non-vector RNAs carrying the MoMuLV psi signal are non-infectious. It is proposed that intracellular expression of packageable non-viral RNAs may represent an effective strategy for inhibiting animal and plant virus replication.

Inhibition of HIV-1 replication by retroviral vectors expressing monomeric and multimeric hammerhead ribozymes

Retroviral vectors were engineered to express monomeric and multimeric hammerhead ribozymes targeting one and nine highly conserved sites within the HIV-1 envelope (Env) coding region. In vitro, both the monomeric and multimeric ribozymes were shown to be active and cleave the target RNA containing the cleavage sites. A human CD4+ T lymphocyte-derived MT4 cell line was stably transduced with retroviral vectors expressing these ribozymes. Ribozyme expression in stably transduced cells was confirmed by Northern blot analysis and reverse-transcription polymerase chain reaction (RT-PCR). As compared with the control cells lacking any ribozyme, HIV-1 replication was delayed in monomeric RzEnv-expressing cells. Virus replication was almost completely inhibited in multimeric RzEnv1-9-expressing cells as no viral RNA or protein could be detected in these cells and in their culture supernatants for up to 60 days after infection. The genomic DNA from RzEnv1-9-expressing cells was shown to contain HIV-1 proviral DNA sequences at days 3 and 60 after HIV infection. HIV-1 used in the challenge experiments was found to contain fully reverse transcribed '-' strand DNA which should have been able to infect complete proviral DNA synthesis and integrate within the cellular genome without being affected by pre-existing ribozymes. Therefore, the proviral DNA present at day 3 after infection may have originated from infection by such DNA-containing virus particles. The results obtained with the retroviral vector expressing RzEnv1-9 are very encouraging and we envisage its future use in anti-HIV-1 gene therapy.

Synthesis and HIV inhibition activity of 2',3'-dideoxy-3'-C-hydroxymethyl nucleosides

A series if 2',3'-dideoxy-3'-C-hydroxymethyl purine nucleosides were prepared based on the photochemical ring expansion of a chiral cyclobutanone precursor, (2S)-trans-2,3-bis[(benzoyloxy)methyl]cyclobutanone, in the presence of a 6-substituted purine. Both alpha- and beta-anomers are produced in this transformation. Deprotection was effected by reaction of the photoadducts with saturated methanolic ammonia. Nine purine nucleosides were tested for their inhibitory effect of HIV IIIB virus on H9 cells. The 6-hexyloxy and adenine derivatives 4e,c, respectively, appeared to be most effective at inhibiting viral reproduction with 4c comparable in activity to ddI and AZT.

Abnormalities of the RB1 and DCC tumor suppressor genes: uncommon in human pancreatic adenocarcinoma

Evidence of RB1 allele loss was found in only 6% of pancreatic cancers, and we found no significant sequence abnormalities nor loss of RB protein expression in a panel of tumors and cell lines. Using reverse transcription-polymerase chain reaction and Southern blot analysis, we found no evidence for loss of DCC expression in pancreatic cancer cell lines, and allele loss only rarely in tumor biopsies. These findings suggest that abnormalities of RB1 and DCC are unlikely to play a major role in pancreatic carcinogenesis.

Expression of hepatocyte growth factor mRNA, and c-met mRNA (hepatocyte growth factor receptor) in human liver tumours

We have quantified mRNA for the hepatocyte growth factor and its putative receptor the c-met proto-oncogene protein product, in a series of human primary and secondary liver tumours and adjacent non-neoplastic liver. In all hepatocellular cancers, hepatocyte growth factor 6 kb mRNA expression was less (mean 23.93% +/- 6.33% S.E.M. n = 7) in the tumours than in the adjacent normal liver. Both relative over- and under-expression of c-met transcripts were found in tumour tissue compared to non-neoplastic liver. Thus hepatocellular cancer tissue does not over-express mRNA for hepatocyte growth factor, though this growth factor might play a role in hyperproliferative states leading to liver cancer.

Chromosome allele loss in colorectal liver metastases and its association with clinical features

Molecular genetic changes are better characterized in colorectal carcinoma than in other common adult tumours. Consistent allele losses, or loss of heterozygosity (LOH), on chromosomes 5q, 17p and 18q have been well established. These changes are associated with the prognosis of the disease. Little is known of such changes in liver metastases of colorectal origin. The extent of allelic loss and its association with clinical features were investigated in 19 patients with colorectal liver metastases by using 24 probes to detect restriction fragment length polymorphism. A high frequency of LOH on chromosomes 5q, 17p and 18q was found in these secondary tumours. No consistent loss has so far been shown in any other chromosome. The frequency of allele loss correlated significantly with prognostic features such as the number and size of liver secondaries (P < 0.005), metastasis to the lymph nodes (P < 0.01) and curative or palliative operation (P < 0.02).

Partial characterization of a cDNA for human stearoyl-CoA desaturase and changes in its mRNA expression in some normal and malignant tissues

A segment of 712 bases coding for part of the human stearoyl-CoA desaturase gene was made by polymerase chain reaction (PCR) using primers based on published rat cDNA sequences. The human PCR product was confirmed by DNA sequencing. It was next cloned into a vector from which anti-sense, highly radioactive RNA transcripts were made in vitro using T7 polymerase. The transcripts were used to probe desaturase mRNA in a number of human tumour and control tissues, using a very sensitive solution hybridization/RNase protection assay. Increased desaturase mRNA levels were found in colonic and oesophageal carcinomas and in hepatocellular adenoma; however, no consistent trend was seen in hepatocellular carcinoma. It is suggested that certain classes of tumour may exhibit increased levels of desaturase mRNA.

Loss of constitutional heterozygosity on chromosomes 5 and 17 in cholangiocarcinoma

It has been established that loss of tumour suppressor genes is crucial in carcinogenesis. There has been no reported study on searching for tumour suppressor genes in cholangiocarcinomas as yet. In order to investigate the loss of heterozygosity (LOH), which may represent such gene loss, in cholangiocarcinoma, we studied 14 patients with this tumour using restriction fragment length polymorphism analysis. Twenty-two probes assigned to chromosomes 1, 5, 7, 9, 11, 12, 13, 14, 16, 17 and 18 were used. Allelic losses were found in chromosomal regions 5q35-qter and 17p13. Loss of genetic material in these regions in cholangiocarcinoma was shared with hepatocellular carcinoma. Probes for other chromosomes have as yet shown no consistent LOH. In conclusion, this study for the first time showed LOH on chromosomes 5 and 17 in cholangiocarcinoma.

Chromosome 17 allele loss in hepatocellular carcinoma but not in synchronous liver adenoma

A 51-year-old female underwent resection of two synchronous liver tumours, a hepatocellular carcinoma and an adenoma. DNA analysis revealed allele loss on chromosome 17 (17p13, near the locus of p53 tumour suppressor gene) in the hepatocellular carcinoma but not in the adenoma. This finding may support the view that loss of p53 tumour suppressor gene is associated with tumour progression.

Infrequent chromosome allele loss in fibrolamellar carcinoma

As yet, there is no reported study of chromosome allele loss in fibrolamellar carcinoma (FLC), a distinct, rare variant of hepatocellular carcinoma (HCC). We searched for evidence of allele loss in FLC using 18 DNA probes for 10 chromosomes and compared the pattern of loss with our series of HCC. Two of the probes, lambda MS32 (1q42-43) and cMS621 (5p) showed allele losses in one tumour, while other probes showed no loss. The frequency of allele loss in FLC was much lower than in HCC, which may be associated with their different prognoses.

The putative tumor suppressor gene on chromosome 5q for hepatocellular carcinoma is distinct from the MCC and APC genes

We have previously shown that the tumor suppressor gene for hepatocellular carcinoma (HCC) without cirrhosis may be located on chromosome 5q35-qter. In this study, we analyzed nine cases of primary HCC without cirrhosis using probes from the MCC and APC genes, which are in the region 5q21-22. None of the informative cases had allele loss detected by these probes, whereas the probe lambda MS8 for the region 5q35-qter showed allele loss in six out of six informative cases. The results confirm that the putative tumor suppressor gene for HCC without cirrhosis on chromosome 5q is distinct from the MCC and APC genes.

Different DNA changes in primary and recurrent hepatocellular carcinoma

DNA restriction fragment length polymorphism analysis was carried out on a primary and recurrent hepatocellular carcinoma in a hepatitis B virus negative patient. For the primary tumour, allele losses were found on the short arm of chromosome 17 (probe: p144-D6, 17p13) and the long arm of chromosome 5 with the probe Lambda MS8 (5q35-qter); other probes showed either no allele loss or a non-informative pattern. The recurrent cancer also showed allele loss with p144-D6, but not with Lambda MS8. In addition, the recurrent tumour had allele losses with Lambda MS43 (12q24.3-qter), pYNZ22 (17p13), and DNA rearrangement revealed by the probe Lambda MS32 (1q42-43), a pattern not seen in the primary lesion. These results indicate that the second hepatocellular carcinoma was of independent clonality and probably represents a de novo neoplasm rather than a recurrence.

Loss of heterozygosity on chromosomes 1 and 11 in carcinoma of the pancreas

Little is known of the molecular-genetic changes in carcinoma of the pancreas (CaP). In order to investigate the allele loss, or loss of heterozygosity (LOH), in CaP, we studied 13 patients with exocrine CaP and two with endocrine CaP using restriction fragment length polymorphism analysis. Twenty probes assigned to chromosomes 1, 5, 7, 9, 11, 12, 13, 14, 16, 17 and 18 were used. The frequency of LOH, or fractional allele loss (FAL), was found in two endocrine tumours to be 0.333 and 0.455 respectively; and FAL in 13 oxocrine tumours ranged from 0 to 0.25. Allele loss was shown in both exocrine and endocrine tumours by the probes Lambda MS1 at 1p33-35, and pMS51 at 11q13. Probes for other chromosomes have as yet shown no consistent LOH. In conclusion, the study showed LOH on chromosomes 1 and 11 in both exocrine and endocrine CaP.

Loss of constitutional heterozygosity on chromosome 5q in hepatocellular carcinoma without cirrhosis

Suppressor gene loci involved in the development of hepatocellular carcinoma (HCC) have not been fully identified. The aim of this study was to look for consistent allele loss, or loss of heterozygosity (LOH), in HCC which might represent such gene loci. We have prepared DNA from tumour and non-tumour material from 16 patients with HCC (nine with and seven without liver cirrhosis). Tumour DNA was compared with non-tumour DNA by Southern analysis performed with a panel of 22 probes recognising restriction fragment length polymorphisms assigned to chromosomes 1, 4, 5, 7, 9, 11, 12, 13, 14, 16, 17, 18 and 20. Non-tumour DNA from five of the seven patients with HCC without cirrhosis was heterozygous with the probe Lambda MS8 (5q35-qter), and in all five there was LOH in tumour DNA. Probes for other regions of chromosome 5 have as yet shown no LOH in this group of patients. Cirrhotic HCC patients exhibited LOH on chromosomes 1q and 5p but not in the region 5q35-qter. Both groups of HCC showed LOH on chromosome 17p13. Screening with other probes has not shown any consistent LOH in either group as yet. A comparison of LOH on chromosome 5 in seven patients with colorectal metastasis in the liver showed a different pattern, which suggests that the proposed tumour suppressor gene locus for HCC without cirrhosis on chromosome 5 appears to be distinct from the familial adenomatous polyposis coli gene.

Prediction of retention indexes. II. Structure-retention index relationship on polar columns

A method is described for the prediction of the retention index (I) from chemical structure, using the number of atoms in the molecule (Z), the I increment for atom addition (A) and the group retention factors (GRFs) of the functional groups and substituents. This method can predict the retention indexes of a wide range of compounds, such as acids, alcohols, amines, acid esters, aldehydes, ketones, ethers, aromatic hydrocarbons, alicyclics, heterocyclics, etc. on polar as well as non-polar columns to within 3% error. Accurate A and GRF values are essential to the prediction. These values can be obtained from homologous series, but a system of arbitrarily assigned A value and adjusted GRFs are also used. The GRFs of the substituents and functional groups depend on the polarity and polarizability of the analyte and the stationary phase and also on the molecular connectivity of the atoms, namely, primary, secondary and tertiary carbon atoms or hydrogen atoms, to which these groups are attached. Highly polar and polarizable groups can alter the A value. When the functionality of a group is masked by substitution, the analyte molecule will tend to behave chromatographically like hydrocarbons. The difficulty in predicting the I values of compounds of multi-functionality by the rule of additivity is the unknown intramolecular interaction that can alter both A and GRF values.

Biomechanical evaluation of cervical spine instability after multiple level laminectomy

Four fresh human cervical spine specimens (C2-T1) were tested both intact and with C5-C6 laminectomies to evaluate the biomechanical effects of multiple level laminectomy. The loads applied to the specimens were physiological and clinically relevant motion patterns were simulated. The results showed that C5 vertical displacements increased by 83.33% in axial compression, 168.75% in flexion, 106.09% in extension, and 35.14% in left bending after C5-C6 laminectomies compared with intact specimens. The increased rates of C6 vertical displacements after laminectomy were slightly lower than C5. The anterior horizontal bulging of C5-6 discs increased by 29.69% in axial compression, 13.86% in flexion, 61.79% in extension, and 13.40% in left bending after laminectomy. The rotational angles of whole specimens had an increase of 15% after laminectomy. The strains in the anterior vertebral bodies and posterior laminae near the articular processes of C5 and C6 were increased significantly after laminectomy. The data indicated that multiple level laminectomy can lead to biomechanical instability of the cervical spine.

Prediction of retention indexes. I. Structure-retention index relationship on apolar columns

A simple method is reported for predicting the retention index (RI) of a chemical compound from the number of carbon and carbon equivalent atoms in the molecule, the RI increment for atom addition and the group retention factors (GRFs) for substituents and functional groups. Atoms other than carbon such as oxygen, nitrogen, sulfur, chlorine, bromine and iodine are assigned carbon atom equivalency of approximately 1, 1, 2, 2, 3 and 4, respectively and are counted for their contribution towards RI prediction. The GRFs of substituents and functional groups are derived from the RIs of reference compounds and series of homologues. Ring structures, ring fusion, ring connection, iso- and neo-carbons, chain branching and unsaturation are also assigned GRFs. The predicted RIs of a number of alicyclic, aliphatic and aromatic hydrocarbons, primary, secondary and tertiary alcohols, phenols, aliphatic amines, aromatic amines, heterocyclics, carboxylic acids, acid esters, aldehydes, ketones, and halogenated compounds, are found to be within +/- 3% of the observed values. The structure-retention index relationship thus developed is extremely useful in the tentative identification of radioactive side products formed in tritium labeling by radiation-induced methods.