High glucose inhibits the survival of HRMCs and its mechanism

OBJECTIVE

High glucose can promote the apoptosis of glomerular mesangial cells and cause diabetic nephropathy (DN). However, the mechanism remains unclear. In the present study, we investigated the effects of high glucose on the survival of human renal mesangial cells (HRMCs).

MATERIALS AND METHODS

Cells were treated with high glucose (30 mM) or normal glucose (5 mM) for 48 hours. Cell proliferation was determined by trypan blue assay. The relative expression of metalloproteinase-3 (TIMP3) and inflammatory factors detected by real-time polymerase chain reaction (PCR). Protein expression of Smad2/3, p-Smad2/3 and Smad7 in HRMCs were analyzed by Western blot.

RESULTS

Compared with normal glucose, we found that high glucose significantly inhibited cell survival, accompanied by the decrease of tissue metalloproteinase-3 (TIMP3) mRNA expression. Western blot results showed that the expression of p-Smad2/3 was significantly up-regulated, the expression of Smad7 was significantly downregulated, and inflammatory factors IL-6/IL-8 mRNA expression were increased in the HRMCs cultured with the high glucose. We also found that, compared with the normal glucose, the level of MDA was significantly increased (p<0.01), and the level of SOD was significantly lower (p<0.05) in the HRMCs cultured with the high glucose.

CONCLUSIONS

These findings suggested that high glucose inhibited the survival of HRMCs and may be associated with the downregulation of TIMP3 expression, Smad signaling pathway, inflammation and oxidative stress.

The Effects of Acarbose on Non-Diabetic Overweight and Obese Patients: A Meta-Analysis

INTRODUCTION

This systematic review aims to verify the efficacy of acarbose monotherapy in treating obese or overweight patients without diabetes.

METHODS

In the study, we conducted a systematic search of the Pub-Med, EMBASE, Cochrane and Science Citation Index Expanded databases in search of clinical trials on acarbose treatment, overweight and obesity. The crucial inclusion criteria were as follows: (1) patients were diagnosed as overweight or obese (BMI ≥ 25 kg/m²); (2) randomized controlled trials (RCTs); (3) patients had undergone acarbose monotherapy or placebo control; (4) acarbose treatment had been carried out for at least 3 months. Exclusion criteria were as follows: (1) patients diagnosed with diabetes mellitus (DM); (2) patients had received a weight loss medication or surgery in the past 3 months; (3) papers not published in English; (4) repeated research results of the same experiment or repeated published documents.

RESULTS

A total of 7 studies involving 132 in the acarbose group and 137 in placebo group, 269 subjects in total, were included in this meta-analysis. From the selected seven papers, we extracted the following clinical parameters: systolic blood pressure (SBP), diastolic blood pressure (DBP), body weight (BW), body mass index (BMI), triglyceride (TG), total cholesterol (TC), low density lipoprotein (LDL), high density cholesterol (HDL) and fasting plasma glucose (FPG). An important finding of our research is that TG was the only significantly reduced parameter in the acarbose group. Weight mean difference (WMD) was - 0.21 (95% CI - 0.33, - 0.09) mmol/l between acarbose (P = 0.0006) and placebo patients. Reduction of BMI was also greater for acarbose than placebo subjects, although the discrepancy was not statistically significant (P = 0.56). Moreover, no hypoglycemia occurred in either the acarbose group or placebo group. A few subjects experienced gastrointestinal reactions, but these were mild and improved over time. Acarbose has no obvious influence on other metabolic indexes.

CONCLUSION

Acarbose monotherapy is beneficial in reducing TG levels in obese or overweight patients and will not result in hypoglycemia during medication. The side effects of acarbose are mild.

Outcomes in patients with severe COVID-19 disease treated with tocilizumab: a case-controlled study

BACKGROUND

COVID-19 is an ongoing threat to society. Patients who develop the most severe forms of the disease have high mortality. The interleukin-6 inhibitor tocilizumab has the potential to improve outcomes in these patients by preventing the development of cytokine release storm.

AIMS

To evaluate the outcomes of patients with severe COVID-19 disease treated with the interleukin-6 inhibitor tocilizumab.

METHODS

We conducted a retrospective, case-control, single-center study in patients with severe to critical COVID-19 disease treated with tocilizumab. Disease severity was defined based on the amount of oxygen supplementation required. The primary endpoint was the overall mortality. Secondary endpoints were mortality in non-intubated patients and mortality in intubated patients.

RESULTS

A total of 193 patients were included in the study. Ninety-six patients received tocilizumab, while 97 served as the control group. The mean age was 60 years. Patients over 65 years represented 43% of the population. More patients in the tocilizumab group reported fever, cough and shortness of breath (83%, 80% and 96% vs. 73%, 69% and 71%, respectively). There was a non-statistically significant lower mortality in the treatment group (52% vs. 62.1%, P = 0.09). When excluding intubated patients, there was statistically significant lower mortality in patients treated with tocilizumab (6% vs. 27%, P = 0.024). Bacteremia was more common in the control group (24% vs. 13%, P = 0.43), while fungemia was similar for both (3% vs. 4%, P = 0.72).

CONCLUSION

Our study showed a non-statistically significant lower mortality in patients with severe to critical COVID-19 disease who received tocilizumab. When intubated patients were excluded, the use of tocilizumab was associated with lower mortality.

[Ikaros family zinc finger 1 mutation is a poor prognostic factor for adult Philadelphia chromosome positive acute lymphoblastic leukemia]

Objective: To analyze the prognostic impact of Ikaros family zinc finger 1(IKZF1) mutation on adult Philadelphia chromosome (Ph1) positive acute lymphoblastic leukemia (ALL) patients. Methods: IKZF1 mutation was detected in 63 adult Ph1 positive ALL patients at diagnosis using capillary electrophoresis. Recruited patients were treated in our center and other three hospitals in Ningbo from January 2014 to January 2017. Clinical data were collected and retrospectively analyzed. Results: Thirty-nine (61.9%) patients were positive IKZF1 mutation in this cohort. The white blood cell (WBC) count in IKZF1 mutation group was significantly higher than that of mutation negative group [(64.6±11.3)×10(9)/L vs. (33.7±5.6)×10(9)/L, P<0.05]. Patients with WBC count over 30×10(9)/L accounted for 56.4% in IKZF1 mutation group. Complete remission (CR) rate in the IKZF1 mutation group was also lower than that of negative group after induction chemotherapy (64.1% vs. 75.0%, P>0.05). IKZF1 was a negative prognostic factor but not independent factor for survival by univariate and multivariate analyses. Patients were divided into chemotherapy and allogeneic transplantation groups. The 3-year overall survival (OS) rate and 3-year leukemia-free survival (LFS) rate in IKZF1 mutation group were significantly lower than those of negative group in both transplantation group (42.3% vs. 59.3%; 31.2% vs. 50.0%; respectively, both P<0.05) and chemotherapy group (24.8% vs. 40.0%; 19.0% vs. 34.3%; respectively, both P<0.05). Conclusion: IKZF1 mutation is a poor prognostic factor for adult Ph1 positive ALL patients.

Early-stage predictors for treatment responses in patients with active lupus nephritis

OBJECTIVE

We analyzed data of lupus nephritis (LN) patients to find parameters that can predict remission.

METHODS

Sixty-four LN patients who were diagnosed with class III, IV, V or V + III/IV by renal biopsy and were followed up for more than six months in our center were enrolled retrospectively. Receiver operating characteristic curves were used to test the predictive values of urinary protein-to-creatinine ratio (UPCR), serum albumin and complement C3 at the first, second and third months as predictors for remission at the sixth month.

RESULTS

The patients' renal pathologies were class III (five cases), class IV (33 cases), class V (nine cases) and class V + III/IV (17 cases). All patients received standard immunosuppressive therapy. Forty-six (71.9%) patients (grouped as the remission group) achieved remission at the end of the sixth month, including 23 complete remissions and 23 partial remissions. The other 18 patients were grouped as the no-remission group. There were no significant differences in clinical data, proportion of immunosuppressive therapy or renal pathological characteristics between the remission group and no-remission group at baseline, except the serum urea nitrogen of the remission group was lower than in the no-remission group. The UPCR were significantly lower in the remission group than in the no-remission group at months 1, 2, 3 and 6, respectively, while the serum albumin was significantly higher in the remission group than in the no-remission group at months 3 and 6, respectively. There were no significant differences in serum creatinine between the remission group and no-remission group, except at month 1. The C3 levels were higher in the remission group than in the no-remission group at months 1, 2 and 3, respectively. The areas under the curve (AUC) of the change percentage of UPCR at month 3 and the serum albumin at month 3 were the most significant (AUC 0.778, p = 0.002; AUC 0.773, p = 0.001, respectively). The cutoff value of the change percentage of UPCR at month 3 was 59%. The cutoff value of serum albumin at month 3 was 32.9g/l.

CONCLUSION

The change percentage of UPCR ≥59% and the serum albumin ≥32.9 g/l at the third month were valuable for predicting remission at the sixth month in LN. Because of the small-size and retrospective nature, this study needs to be validated.

The effects of metformin on simple obesity: a meta-analysis

OBJECTIVE

To evaluate the efficacy of metformin versus a placebo in the treatment of patients with simple obesity without obesity related diseases.

METHODS

A search was done on Pub-Med, EMBASE, Cochrane, and Science Citation Index Expanded databases. The main inclusion criteria included the following:(1) randomized controlled trials. (2) patients diagnosed as being overweight or obese. (3) patients were randomly assigned to receive metformin or control. Exclusion criteria included the following: patients diagnosed with an obesity related disease, such as diabetes mellitus (DM) or polycystic ovary syndrome (PCOS).

RESULTS

Compared with the placebo, weighted mean difference (WMD) was 2.33 (95% CI 0.31, 4.35) kg higher with metformin (p = 0.02). Compared with the placebo, WMD was 0.57 (95% CI 0.35, 0.79) kg/m² higher with metformin(p < 0.00001). There was no significant difference in the reduction of waist circumference between the metformin group and the control group (p = 0.05). The fasting blood glucose levels were significantly lower in the metformin group than in the control group (p < 0.00001). However, no hypoglycemia was noted in the metformin group or the control group.

CONCLUSION

Metformin is effective in reducing body weight of simple obesity patients, and metformin does not induce hypoglycemia as a side effect.

Abstract P4-13-03: Variations in breast reconstruction rate in France according to patient and site characteristics: A nationwide retrospective study of nearly 20,000 patients

Background: Breast reconstruction (BR) for women who undergo mastectomy for cancer offers psychological benefits and improves quality of life. However its use remains limited, especially for women over 65 years, with a large degree of international variation. The aim of this study was to find out factors influencing the surgical decision of BR in France where cancer related healthcare costs are fully reimbursed.

Methods: We used the French medico-administrative database to identify all primary mastectomies for breast carcinoma in 2012 and studied the rate of immediate (IR) or delayed breast reconstruction (DR) up to December 2015.

Variations of BR rates were evaluated according to

- patient age, social deprivation index,

- profile of the hospital where the mastectomy was performed: type of hospital (cancer center, CC; university hospitals, UH; private, PrivH; or public, PubH), and hospital activity (surgical acts for breast cancer in 2012);

- disparities across administrative regions in terms of number of CC or UH, number of plastic surgeons, gynecologist-obstetrician surgeons and general surgeons in the region.

A hierarchical three-level logistic regression was used with SAS GLIMMIX to model the probability of BR taking into account clustering of observations (patients in hospitals, hospitals in regions). Splines were used to explore the functional form of the relationship between continuous variables and BR rate. Akaike information criterion was used for model selection.

Results: Among the 19,466 women who had a mastectomy in 2012, 5,328 (27.4%) subsequently had a BR: IR for 13.7% and DR for 13.7%. The BR rate significantly varied with age (p&lt;0.0001), resulting in a much smaller BR rate in patients older than 65 compared to younger (7.5% vs 42.1%, p&lt;0.0001). In case of BR, IR was more frequent than DR in older patients (66% of BR), whereas both were equally balanced before 65. BR rates decreased with increasing social deprivation index (from 32.7% to 21.5%, from the first to the fourth quartile of the distribution). BR rates significantly varied according to hospital type (35.0% in CC, 29.8% in UH, 25.9% in PrivH and 18.6% in PubH). BR rates were significantly lower in small activity hospital (varying from 13.4% in hospital with &lt;=50 annual breast surgery to 35.1% in hospitals with &gt;500), especially in older patients (varying from 3.1% to 10.3%). We also observed important heterogeneity of BR rates across administrative regions, but these variations were not explained by the number of CC or UH, the number of plastic surgeons, the number of gynecologist-obstetrician surgeons or the number of general surgeons in the region. In multivariate analysis, BR rate was significantly associated with age (p&lt;0.0001), social deprivation index (p&lt;0.0001), type of hospital (p=0.002) and hospital activity (p&lt;0.0001), with persistent heterogeneity across administrative regions.

Conclusions: We identified substantial variations in BR rates across the French hospitals. Controlling for possible confounders, older patients have less breast reconstruction. This apparent heterogeneity can be part of women choice, however it suggests unequal access to high quality procedures for older women with breast cancer.

Citation Format: Regis C, Le J, Le Teuff G, Cucchi M, Boulanger L, Hannebicque K, Giard S, Chauvet M-P, Quemenr J, Ledeley M-C. Variations in breast reconstruction rate in France according to patient and site characteristics: A nationwide retrospective study of nearly 20,000 patients [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-13-03.

Effects of vancomycin versus nafcillin in enhancing killing of methicillin-susceptible Staphylococcus aureus causing bacteremia by human cathelicidin LL-37

Recent studies have demonstrated that anti-staphylococcal beta-lactam antibiotics, like nafcillin, render methicillin-resistant Staphylococcus aureus (MRSA) more susceptible to killing by innate host defense peptides (HDPs), such as cathelicidin LL-37. We compared the effects of growth in 1/4 minimum inhibitory concentration (MIC) of nafcillin or vancomycin on the LL-37 killing of 92 methicillin-susceptible S. aureus (MSSA) isolates. For three randomly selected strains among these, we examined the effects of nafcillin, vancomycin, daptomycin, or linezolid on LL-37 killing and autolysis. Growth in the presence of subinhibitory nafcillin significantly enhanced LL-37 killing of MSSA compared to vancomycin and antibiotic-free controls. Nafcillin also reduced MSSA production of the golden staphylococcal pigment staphyloxanthin in 39 % of pigmented strains vs. 14 % for vancomycin. Among the antibiotics tested, only nafcillin resulted in significantly increased MSSA autolysis. These studies point to additional mechanisms of anti-staphylococcal activity of nafcillin beyond direct bactericidal activity, properties that vancomycin and other antibiotic classes do not exhibit. The ability of nafcillin to enhance sensitivity to innate HDPs may contribute to its superior effectiveness against MSSA, as suggested by studies comparing clinical outcomes to vancomycin treatment.

Anxiety prevalence following spinal cord injury: a meta-analysis

STUDY DESIGN

Meta-analysis.

OBJECTIVES

Prevalence estimates indicate that anxiety following spinal cord injury (SCI) is a common problem. However, methodological differences between studies may impact the clinical interpretation of these data.

METHODS

Data from 18 independent studies (Nparticipants=3158), which reported the prevalence of an anxiety disorder or associated symptoms, were identified from the Embase, PubMed and PsycInfo databases. Proportions were the primary effect size estimate. Confidence intervals, fail-safe Ns and the I(2) statistic were additionally calculated to identify the extent to which findings were robust and consistent across studies.

RESULTS

Five per cent of participants met the criteria for either GAD or panic disorder, with Agoraphobia identified in 2.5%. These diagnostic data were, however, limited to two studies. Higher rates were noted for self-reported 'caseness' of anxiety, with 27% reporting clinically significant symptoms. Anxiety prevalence estimates varied across the individual self-report measures (range: 15-32%). Method of administration (range: 26-32%) did not impact significantly on these estimates nor did recruitment source, with similarly high anxiety levels reported by hospital (27%) and community (29%) samples.

CONCLUSIONS

Early identification and treatment of anxiety are important in SCI rehabilitation, with a subgroup of individuals experiencing chronic symptoms. Further research is needed to establish guidelines for the interpretation of self-report data, including the use of clinical cutoffs.

Rapid hippocampal network adaptation to recurring synchronous activity--a role for calcineurin

Neuronal networks are thought to gradually adapt to altered neuronal activity over many hours and days. For instance, when activity is increased by suppressing synaptic inhibition, excitatory synaptic transmission is reduced. The underlying compensatory cellular and molecular mechanisms are thought to contribute in important ways to maintaining normal network operations. Seizures, due to their massive and highly synchronised discharging, probably challenge the adaptive properties of neurons, especially when seizures are frequent and intense - a condition common in early childhood. In the experiments reported here, we used rat and mice hippocampal slice cultures to explore the effects that recurring seizure-like activity has on the developing hippocampus. We found that developing networks adapted rapidly to recurring synchronised activity in that the duration of seizure-like events was reduced by 42% after 4 h of activity. At the same time, the frequency of spontaneous excitatory postsynaptic currents in pyramidal cells, the expression of biochemical biomarkers for glutamatergic synapses and the branching of pyramidal cell dendrites were all dramatically reduced. Experiments also showed that the reduction in N-methyl-D-aspartate receptor subunits and postsynaptic density protein 95 expression were N-methyl-D-aspartate receptor-dependent. To explore calcium signaling mechanisms in network adaptation, we tested inhibitors of calcineurin, a protein phosphatase known to play roles in synaptic plasticity and activity-dependent dendrite remodeling. We found that FK506 was able to prevent all of the electrophysiological, biochemical, and anatomical changes produced by synchronised network activity. Our results show that hippocampal pyramidal cells and their networks adapt rapidly to intense synchronised activity and that calcineurin play an important role in the underlying processes.

Uncoupling of bacterioplankton and phytoplankton production in fresh waters is affected by inorganic nutrient limitation

Pelagic bacterial production is often positively correlated, or coupled, with primary production through utilization of autotrophically produced dissolved organic carbon. Recent studies indicate that inorganic N or P can directly limit both bacterial and phytoplanktonic growth. Our mesocosm experiments, with whole communities from mesotrophic Calder Lake, test whether this apparent bacterial-algal coupling may be the result of independent responses to limiting inorganic nutrients. In systems without N additions, numbers of bacteria but not phytoplankton increased 2- to 2.5-fold in response to P fertilization (0 to 2.0 mumol of P per liter); this resulted in uncoupled production patterns. In systems supplemented with 10 mumol of NH(4)NO(3) per liter, P addition resulted in up to threefold increases in bacteria and two- to fivefold increases in total phytoplankton biomass (close coupling). P limitation of pelagic bacteria occurred independently of phytoplankton dynamics, and regressions between bacterial abundance and phytoplankton chlorophyll a were nonsignificant in all systems without added N. We describe a useful and simple coupling index which predicts that shifts in phytoplankton and bacterioplankton growth will be unrelated (Delta bacteria/Delta phytoplankton --> either + infinity or - infinity) in systems with inorganic N/P (molar) ratios of < approximately 40. In systems with higher N/P ratios (>40), the coupling index will approach 1.0 and close coupling between bacteria and phytoplankton is predicted to occur.

Analysis of CARD15/NOD2 haplotypes fails to identify common variants associated with rheumatoid arthritis susceptibility

OBJECTIVES

The CARD15/NOD2 gene product plays an important role in host response to bacterial lipopolysaccharides and bacterial muramyl dipeptide via activation of NF-kappaB in monocytes. Mutations in CARD15 are associated with Crohn's disease (CD), a chronic inflammatory bowel disease. In this study we sought to determine whether CD-associated mutations or any common variants of this gene might contribute to susceptibility to another chronic inflammatory disease, rheumatoid arthritis (RA).

METHODS

We genotyped 376 Caucasian RA cases and 376 ethnically matched healthy controls for three CD-associated CARD15 mutations. We also genotyped these 752 individuals for 12 common CARD15 single nucleotide polymorphisms (SNPs), determined the linkage disequilibrium structure of the gene, and compared the frequencies of the common CARD15 haplotypes in the RA cases and controls.

RESULTS

None of the CD-associated mutations or the CARD15 SNPs was associated with susceptibility to RA. We also found no significant difference in the frequencies of any of the common haplotypes of the CARD15 gene in RA patients and controls. Our haplotype analysis was consistent with earlier observations that all three CD-associated variants independently arose on the same ancestral haplotype.

CONCLUSIONS

These data suggest that CARD15 variants are not associated with RA susceptibility.

Production of matrix metalloproteinase 2 in fibroblast reaction to mechanical stress in a collagen gel

The reaction of fibroblasts to mechanical forces generated by fibroblasts themselves in anchored collagen lattices was studied. Fibroblasts were cast in collagen gels. Free retracted gels (RG) were compared with stressed gels (SG) in 3-day and 14-day experiments. As previously described, SG showed an increase in protein, mainly collagen, biosynthesis. Matrix metalloproteinases (pro-MMP-2 and MMP-2) were studied by zymography. Certain cell membrane components, integrin alpha(2) and phosphatidylserine, were studied by flow cytometry with antibodies against the integrin alpha(2) subunit and with annexin V binding. Mechanical stress stimulated production of pro-MMP-2 both in the short-term (3-day) and the longer term (14-day) cultures. However, the pro-enzyme was not more activated and there was no difference in the amount of MMP-2 between RG and SG. There was only an increase with time under both conditions. The stressed fibroblasts reacted early with an increase in the integrin alpha(2) subunit, but the stimulated cells disappeared from the 14-day cultures. The number of cells measured in terms of the amount of DNA decreased between day 3 and day 14, mainly in the SG due to cytolysis. This cell stress was related to an alteration in the plasma membrane detected by the annexin V marker.

[The clinical value of the TSGF pre and post-therapy in patients with nasopharyngeal carcinoma(NPC)]

OBJECTIVE

To investigate the role of TSGF (tumor supplied group of factor) in early diagnosing and predicting in patients with NPC.

METHOD

EBV-IgA and level of TSGF were measured before therapy and 1 month, 1 year after therapy in 35 patients with NPC, and the relationship between them was researched.

RESULT

The diagnostic sensitivity of TSGF and EBV-IgA was 91%, 97% respectively, there is no significant relation between them. After treatment, the level of TSGF in PD (progression disease) patient remained higher, but had a significantly drop in RR(including the CR, PR and SI)) patient.

CONCLUSION

Results suggested that TSGF may be useful in diagnosing and prediction of NPC.

The solubility of gases and vapours in dry octan-1-ol at 298 K

Ostwald solubility coefficients of 74 compounds in dry octan-1-ol at 298 K have been determined, and have been combined with literature values and additional values we have calculated from solubilities in dry octan-1-ol and vapour pressures to yield a total of 161 log L(OctOH) values at 298 K. These L(OctOH) values are identical to gas-to-dry octan-1-ol partition coefficients, often denoted as K(OA). Application of the solvation equation of Abraham to 124 values as a training set yielded a correlation equation with n = 124, S.D. = 0.125, r2 = 0.9970 and F = 7731. This equation was then used to predict 32 values of log L(OctOH) as a test set, giving a standard deviation, S.D. of 0.131, an average absolute deviation of 0.085 and an average deviation of -0.009 log units. The solvation equation for the combined 156 log L(OctOH) values was log L(OctOH) = -0.120 - 0.203R2 + 0.560pi2(H) + 3.560 sum(alpha2(H)) + 0.702 sum(beta2(H)) + 0.939 logL16, n =156, r2 = 0.9972, S.D. = 0.125, F = 10573, where, n is the number of data points (solutes), r the correlation coefficient, S.D. the standard deviation and F is the F-statistic. The independent variables are solute descriptors as follows: R2 is an excess molar refraction, pi2(H) the dipolarity/polarisability, sum(alpha2(H)) the overall or summation hydrogen-bond acidity, sum(beta2(H)) the overall or summation hydrogen-bond basicity and L16 is the Ostwald solubility coefficient on hexadecane at 298 K. The equation is consistent with similar equations for the solubility of gases and vapours into methanol, ethanol and propan-1-ol. It is suggested that the equation can be used to predict further values of log L(OctOH), for which the solute descriptors are known, to within 0.13 log units.

A comparison of F-actin labeling methods for light microscopy in different plant specimens: multiple techniques supplement each other

Different detection methods for F-actin labeling were compared on a range of plant specimens: cultured cells, whole organ mounts and sectioned material. For cultured cells, microinjection of labeled phalloidin yielded the most detailed picture but careful permeation methods come close, while immunocytochemical methods always gave relatively poor detail, especially on the level of the fine filaments. For whole organ mounts and sectioned material, permeation methods and immunolocalization are the methods of choice, however never reaching the level of resolution of permeation methods in single cells. It is clear that there is no general and universal good method and multiple techniques are needed, especially when working with different specimens and with different aims.

Fc receptor-mediated phagocytosis makes a significant contribution to clearance of influenza virus infections

Fc receptors for IgG expressed on macrophages and NK cells are important mediators of opsonophagocytosis and Ab-dependent cell-mediated cytotoxicity. Phagocyte-mediated opsonophagocytosis is pivotal for protection against bacteria, but its importance in recovery from infection with intracellular pathogens is unclear. We have now investigated the role of opsonophagocytosis in protection against lethal influenza virus infection by using FcR gamma(-/-) mice. Absence of the FcR gamma-chain did not affect the expression of IFN-gamma and IL-10 in the lungs and spleens after intranasal immunization with an influenza subunit vaccine. Titers of serum and respiratory Abs of the IgM, IgG1, IgG2a, and IgA isotypes in FcR gamma(-/-) mice were similar to levels seen in FcR gamma(+/+) mice. Nevertheless, FcR gamma(-/-) mice were highly susceptible to influenza infection, even in the presence of anti-influenza Abs from immune FcR gamma(+/+) mice. NK cells were not necessary for the observed Ab-mediated viral clearance, but macrophages were found to be capable of actively ingesting opsonized virus particles. We conclude that Fc receptor-mediated phagocytosis plays a pivotal role in clearance of respiratory virus infections.

The epithelium-specific ETS protein EHF/ESE-3 is a context-dependent transcriptional repressor downstream of MAPK signaling cascades

Exon trapping and cDNA selection procedures were used to search for novel genes at human chromosome 11p13, a region previously associated with loss of heterozygosity in epithelial carcinomas. Using these approaches, we found the ESE-2 and ESE-3 genes, coding for ETS domain-containing transcription factors. These genes lie in close proximity to the catalase gene within a approximately 200-kilobase genomic interval. ESE-3 mRNA is widely expressed in human tissues with high epithelial content, and immunohistochemical analysis with a newly generated monoclonal antibody revealed that ESE-3 is a nuclear protein expressed exclusively in differentiated epithelial cells and that it is absent in the epithelial carcinomas tested. In transient transfections, ESE-3 behaves as a repressor of the Ras- or phorbol ester-induced transcriptional activation of a subset of promoters that contain ETS and AP-1 binding sites. ESE-3-mediated repression is sequence- and context-dependent and depends both on the presence of high affinity ESE-3 binding sites in combination with AP-1 cis-elements and the arrangement of these sites within a given promoter. We propose that ESE-3 might be an important determinant in the control of epithelial differentiation, as a modulator of the nuclear response to mitogen-activated protein kinase signaling cascades.

Evaluation of human intestinal absorption data and subsequent derivation of a quantitative structure–activity relationship (QSAR) with the Abraham descriptors

The human intestinal absorption of 241 drugs was evaluated. Three main methods were used to determine the human intestinal absorption: bioavailability, percentage of urinary excretion of drug-related material following oral administration, and the ratio of cumulative urinary excretion of drug-related material following oral and intravenous administration. The general solvation equation developed by Abraham's group was used to model the human intestinal absorption data of 169 drugs we considered to have reliable data. The model contains five Abraham descriptors calculated by the ABSOLV program. The results show that Abraham descriptors can successfully predict human intestinal absorption if the human absorption data is carefully classified based on solubility and administration dose to humans.

Fate and toxicity of endosulfan in Namoi River water and bottom sediment

Endosulfan (6,7,8,9,10,10,-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodioxathiepine-3-oxide) sorption (standardized to 1% total organic carbon and dry weight) was significantly (P < 0.05) more concentrated on the large (>63 microm) particle fraction compared with smaller size fractions (<5 microm and 5-24 microm) of bottom sediments from the Namoi River, Australia. Following completion of the particle size fractionation (6 to 12 wk) and a sediment toxicity assessment (2 wk), the sediments showed large decreases in concentrations of alpha-endosulfan that coincided with an increase in endosulfan sulfate concentrations and minimal changes in beta-endosulfan concentrations. In the Namoi River, similar patterns were observed in the composition of total endosulfan in monthly measurements of bottom sediments and in passive samplers placed in the water column following runoff from cotton (Gossypium hirsutum L.) fields. The toxicity of endosulfan sulfate in river water indicated by the nymphs of the epibenthic mayfly Jappa kutera, was more persistent than the alpha- and beta-endosulfan parent isomers due to its longer half-life. This suggests that endosulfan sulfate would contribute most to previously observed changes in population densities of aquatic biota. Measured concentrations of total endosulfan in river water of up to 4 microg L(-1) following storm runoff, exceed the range of the 96-h median lethal concentration (LC50) values in river water for both alpha-endosulfan (LC50 = 0.7 microg L(-1); 95% confidence interval [CI] = 0.5 to 1.1) and endosulfan sulfate (LC50 = 1.2 microg L(-1); 95% CI = 0.4 to 3.3). In contrast, the 10-d LC50 value for total endosulfan in the sediment toxicity test (LC50 = 162 microg kg(-1); 95% CI = 120 to 218 microg kg(-1)) was more than threefold higher than the highest measured concentration of total endosulfan in field samples of bottom sediment (48 microg kg(-1)). This suggests that pulse exposures of endosulfan in the water column following storm runoff may be more acutely toxic to riverine biota than in contaminated bottom sediment.

Implanon: a critical review

OBJECTIVE

To evaluate clinical information on Implanon as a long-term method of contraception and, specifically, to review the efficacy and adverse effect profile of Implanon.

DATA SOURCES

A MEDLINE search (from 1966 through June 1999) was performed to retrieve primary and review articles. The search was limited to data on human subjects. Some references were identified through secondary sources.

STUDY SELECTION AND DATA EXTRACTION

Pharmacokinetic and pharmacodynamic studies, and clinical trials assessing the efficacy and safety of desogestrel implants were reviewed. Relevancy and consistency of information was assessed for each trial.

DATA SYNTHESIS

Implanon is the newest contraceptive implant system that has completed worldwide Phase III clinical trials. It is a single rod that contains a core of 68 mg of 3-keto-desogestrel with a membrane of ethylene vinyl acetate. Inhibition of ovulation occurs within one day of implantation, and effective contraception lasts for three years. Fertility returns within one month after implant removal. Insertion and removal by trained medical professionals is simple, and only minor complications have been documented. Adverse effects are mild and primarily consist of abnormal bleeding, weight gain, acne, breast pain, and headache.

CONCLUSIONS

The data on Implanon indicate that it provides effective long-term contraception with limited adverse effects. It appears to be a good addition to the currently available contraceptives.

[Protective effect of erigeron injections on hepatotoxicity induced by intestinal ischemia-reperfusion in mice]

The liver injury was induced by intestinal ischemia-reperfusion and the protective effect of erigeron injection (EI) was studied in mice. The results showed that serum alanine transaminase (ALT) and glutathione S-transferase (GST) activity increased while the root of superior mesenteric artery was blocked with non-injury artery clap for 20 minute and reperfusion for 1 hour. EI could protect the above changes induced by intestinal ischemia-reperfusion. EI could reduce the activities of serum ALT and GST, decrease the content of hepatic MDA and significantly increase the activity of SOD. The pathological changes of hepatocytes induced by intestinal ischemia-reperfusion were less in EI groups. These results suggested that EI could protect the liver of mice from injury induced by intestinal ischemia-reperfusion. One of the mechanisms of hepatoprotective action was related to the antioxidative function of erigeron.

IgA immunodeficiency leads to inadequate Th cell priming and increased susceptibility to influenza virus infection

IgA is considered to be the principal Ab involved in defense against pathogens in the mucosal compartment. Using mice with a targeted disruption in IgA gene expression (IgA(-/-) mice), we have examined the precise role of IgA in protective anti-influenza responses after intranasal vaccination. IgA(-/-) mice immunized intranasally with soluble hemagglutinin (hemagglutinin subtype 1) and neuraminidase (neuraminidase subtype 1) vaccine in the absence of adjuvant were found to be more susceptible to influenza virus infection than IgA(+/+) mice (13 vs 75% survival after virus challenge). Inclusion of IL-12 during immunization restored the protective efficacy of the vaccine to that seen in IgA(+/+) animals. IgA(-/-) mice had no detectable IgA expression, but displayed enhanced serum and pulmonary IgM and IgG Ab levels after IL-12 treatment. Assessment of T cell function revealed markedly depressed splenic lymphoproliferative responses to PHA in IgA(-/-) animals compared with IgA(+/+) mice. Furthermore, IgA(-/-) animals displayed impaired T cell priming to the H1N1 subunit vaccine, with concomitant reduction in recall memory responses due to a defect in APC function. Collectively, these results provide evidence that a major role of IgA is to facilitate presentation of Ag to mucosal T cells. IL-12 treatment can overcome IgA deficiency by providing adequate T cell priming during vaccination.

Development of disulfide peptide mapping and determination of disulfide structure of recombinant human osteoprotegerin chimera produced in Escherichia coli

Recombinant human osteoprotegerin chimera is a 90-kDa protein containing a human IgG Fc domain fused to human osteoprotegerin. The molecule is a dimer linked by two intermolecular disulfide bonds and contains eleven intramolecular disulfide bonds per monomer. A cysteine-rich region in osteoprotegerin contains nine disulfide bridges homologous to the cysteine-rich signature structure of the tumor necrosis factor receptor/nerve growth factor receptor superfamily. In this report, we have developed peptide mapping procedures suitable to generate disulfide-containing peptides for disulfide structure assignment of the fusion molecule. The methods employed included proteolytic digestion using endoproteinases Glu-C and Lys-C in combination followed by LC-MS analyses. Disulfide linkages of peptide fragments containing a single disulfide bond were assigned by sequence analysis via detection of (phenylthiohydantoinyl) cystine and/or by MS analysis. Disulfide bonds of a large, core fragment containing three peptide sequences linked by four disulfides were assigned after generation of smaller disulfide-linked peptides by a secondary thermolysin digestion. Disulfide structures of peptide fragments containing two disulfide bonds were assigned using matrix-assisted laser desorption ionization mass spectrometry with postsource decay. Both the inter- and intramolecular disulfide linkages of the chimeric dimer were confirmed.

Negative regulation of lymphocyte activation and autoimmunity by the molecular adaptor Cbl-b

The signalling thresholds of antigen receptors and co-stimulatory receptors determine immunity or tolerance to self molecules. Changes in co-stimulatory pathways can lead to enhanced activation of lymphocytes and autoimmunity, or the induction of clonal anergy. The molecular mechanisms that maintain immunotolerance in vivo and integrate co-stimulatory signals with antigen receptor signals in T and B lymphocytes are poorly understood. Members of the Cbl/Sli family of molecular adaptors function downstream from growth factor and antigen receptors. Here we show that gene-targeted mice lacking the adaptor Cbl-b develop spontaneous autoimmunity characterized by auto-antibody production, infiltration of activated T and B lymphocytes into multiple organs, and parenchymal damage. Resting cbl-b(-/-) lymphocytes hyperproliferate upon antigen receptor stimulation, and cbl-b(-/-) T cells display specific hyperproduction of the T-cell growth factor interleukin-2, but not interferon-gamma or tumour necrosis factor-alpha. Mutation of Cbl-b uncouples T-cell proliferation, interleukin-2 production and phosphorylation of the GDP/GTP exchange factor Vav1 from the requirement for CD28 co-stimulation. Cbl-b is thus a key regulator of activation thresholds in mature lymphocytes and immunological tolerance and autoimmunity.

Mineralization and alkaline phosphatase activity in collagen lattices populated by human osteoblasts

Adult human osteoblastic cells were grown in a native type I collagen gel. Proliferation and viability analyses showed that cells rapidly stopped dividing and became blocked in the G0G1 phase (91% on day 13). Carboxyfluorescein diacetate cell staining and flow cytometry showed that osteoblasts were viable for the first 16 days and then viability decreased (58% viable cells on day 22). Osteoblasts were able to retract the matrix. Betaglycerophosphate (betaGP) stimulated the deposition of mineral particles in the collagen network, and electron probe microanalysis showed that they were principally calcium and phosphorus, with a Ca/P ratio of about 1.7. Various times of betaGP supply were tested. We compared 10 mM betaGP added only once at day 0, or continuously from day 0, day 8, or day 21. Mineralization was observed in conditions where betaGP was added at day 0. Furthermore, 10 mM betaGP added once during gel preparation was sufficient to induce mineralization with mineral accumulation up to day 15 whereas the speed of the gel contraction decreased. In every condition, cultures expressed high alkaline phosphatase (ALP) levels as early as day 3, which decreased afterwards. These kinetics might explain why the other conditions did not prove favorable to the mineralization process. The model was used to study the influence of blocking gel retraction. Blocking retraction delayed the ALP activity decrease, but had no effect on mineralization. In conclusion, human adult osteoblasts cultured in native collagen gel stopped proliferation and underwent mineralization very early. This model should be used to investigate the influence of effectors on the early stages of culture.

Urine glycyl-L-proline increase and skin trophicity

Glycyl-L-proline (gly-pro) is an end product of collagen metabolism that is further cleaved by prolidase (EC 3.4.13.9); the resulting proline molecules are recycled into collagen or other proteins. We postulated a relationship between defective gly-pro hydrolysis, increased collagen degradation and skin destruction. This relationship was tested using HPLC to measure the gly-pro in urine. 24 hour urine samples were collected from 27 old people (86 +/- 6 years old), of whom 15 were suffering from skin pressure sores of the sacrum or calcaneus. The urine from patients with pressure sores contained significantly more gly-pro than the urine from the control. A cut-off at 7 mumol/mmol creatinine gave the test a positive predictive value of 70%. Collagen breakdown was also increased as indicated by the increase of hydroxyproline (hyp) in the urine. But this breakdown seemed to stop at the gly-pro step.

The correlation and prediction of the solubility of compounds in water using an amended solvation energy relationship

The aqueous solubility of liquids and solids, as log S(W), has been correlated with an amended solvation equation that incorporates a term in Sigma alpha(2)(H) x Sigma beta(2)(H), where the latter are the hydrogen bond acidity and basicity of the solutes, respectively. Application to a training set of 594 compounds led to a correlation equation with a standard deviation, SD, of 0.56 log units. For a test set of 65 compounds, the SD was 0.50 log units, and for a combined correlation equation for 659 compounds, the SD was 0.56 log units. The correlation equations enable the factors that influence aqueous solubility to be revealed. The hydrogen-bond propensity of a compound always leads to an increase in solubility, even though the Sigma alpha(2)(H) x Sigma beta(2)(H) term opposes solubility due to interactions in the liquid or solid. Increase in solute dipolarity/polarizability increases solubility, whereas an increase in solute excess molar refraction, and especially, volume decrease solubility. The solubility of Bronsted acids and bases is discussed, and corrections for the fraction of neutral species in the saturated solution are graphically presented.

Electroencephalographic imaging of higher brain function

High temporal resolution is necessary to resolve the rapidly changing patterns of brain activity that underlie mental function. Electroencephalography (EEG) provides temporal resolution in the millisecond range. However, traditional EEG technology and practice provide insufficient spatial detail to identify relationships between brain electrical events and structures and functions visualized by magnetic resonance imaging or positron emission tomography. Recent advances help to overcome this problem by recording EEGs from more electrodes, by registering EEG data with anatomical images, and by correcting the distortion caused by volume conduction of EEG signals through the skull and scalp. In addition, statistical measurements of sub-second interdependences between EEG time-series recorded from different locations can help to generate hypotheses about the instantaneous functional networks that form between different cortical regions during perception, thought and action. Example applications are presented from studies of language, attention and working memory. Along with its unique ability to monitor brain function as people perform everyday activities in the real world, these advances make modern EEG an invaluable complement to other functional neuroimaging modalities.

A comparison of 15N proline and 13C leucine for monitoring protein biosynthesis in the skin

The tracers L 15N-proline and L(1-13C)-leucine were used to explore the synthesis of skin proteins in vivo in rabbits. They orally received a single dose containing an equimolecular mixture of L(1-13C)-leucine and L 15N-proline. The changes in the amounts of these tracers in blood and skin were monitored for a total of 8 h. The data showed the appearance of the two tracers in blood within 15 min and their clearance in 8 h. They were both rapidly (15 min) incorporated into skin proteins, but more proline was incorporated than leucine. We therefore consider L 15N-proline to be a better tracer than L(1-13C)-leucine for studying protein metabolism in the skin.

Deblurring

In most instances, traditional EEG methodology provides insufficient spatial detail to identify relationships between brain electrical events and structures and functions visualized by magnetic resonance imaging or positron emission tomography. This article describes a method called Deblurring for increasing the spatial detail of the EEG and for fusing neurophysiologic and neuroanatomic data. Deblurring estimates potentials near the outer convexity of the cortex using a realistic finite element model of the structure of a subject's head determined from their magnetic resonance images. Deblurring is not a source localization technique and thus makes no assumptions about the number or type of generator sources. The validity of Deblurring has been initially tested by comparing deblurred data with potentials measured with subdural grid recordings. Results suggest that deblurred topographic maps, registered with a subject's magnetic resonance imaging and rendered in three dimensions, provide better spatial detail than has heretofore been obtained with scalp EEG recordings. Example results are presented from research studies of somatosensory stimulation, movement, language, attention and working memory. Deblurred ictal EEG data are also presented, indicating that this technique may have future clinical application as an aid to seizure localization and surgical planning.

The oncogene product Vav is a crucial regulator of primary cytotoxic T cell responses but has no apparent role in CD28-mediated co-stimulation

The guanine nucleotide-exchange factor Vav is a regulator of antigen-mediated cytoskeletal reorganization required for receptor clustering, proliferation and thymic selection. Moreover, Vav has been identified as a major substrate in the CD28 signal transduction pathway and overexpression of Vav enhances TCR-mediated IL-2 secretion in T cells. Here we show that CD3- plus CD28-mediated proliferation and IL-2 production were reduced in vav gene-deficient T cells. However, Vav had no apparent role in phorbol 12-myristate 13-acetate-plus CD28-mediated proliferation and IL-2 production, suggesting that Vav acts downstream of the TCR/CD3 complex. In vivo, Vav expression was crucial to generate primary vesicular stomatitis virus (VSV)-specific cytotoxic T cell responses. In contrast, vav-/- mice exhibited a reduced but significant footpad swelling after lymphocytic choriomeningitis virus (LCMV) infections and mounted a measurable primary cytotoxic T cell response to LCMV. Upon in vitro restimulation, cytotoxic T cell responses of both VSV- and LCMV-infected mice reached near normal levels. Our data provide the first genetic evidence that Vav is an important effector molecule that relays antigen receptor signaling to IL-2 production and activation of cytotoxic T cells.