Antiphospholipid antibodies and subsequent thrombo-occlusive events in patients with ischemic stroke

CONTEXT

The presence of antiphospholipid antibodies (aPL) has been associated with vascular occlusive events. However, the role of aPL in predicting ischemic events, particularly recurrent ischemic stroke, is controversial.

OBJECTIVE

To evaluate the effect of baseline aPL positivity (ie, positivity for anticardiolipin antibodies [aCL], lupus anticoagulant antibodies [LA], or both) on subsequent thrombo-occlusive events, including recurrent stroke.

DESIGN, SETTING, AND PARTICIPANTS

The Antiphospholipid Antibodies and Stroke Study (APASS), a prospective cohort study within the Warfarin vs Aspirin Recurrent Stroke Study (WARSS), a randomized double-blind trial (N = 2206) conducted at multiple US clinical sites from June 1993 through June 2000 and comparing adjusted-dose warfarin (target international normalized ratio, 1.4-2.8) and aspirin (325 mg/d) for prevention of recurrent stroke or death. APASS participants were 1770 (80%) WARSS participants who consented to enroll in the APASS, with usable baseline blood samples drawn prior to randomization to the WARSS and analyzed for aPL status within 90 days of index stroke by a central independent laboratory. Quality assurance was performed on approximately 10% of samples by a second independent laboratory.

MAIN OUTCOME MEASURE

Two-year rate of the composite end point of death from any cause, ischemic stroke, transient ischemic attack, myocardial infarction, deep vein thrombosis, pulmonary embolism, and other systemic thrombo-occlusive events. The primary analysis assessed the outcome associated with aPL positivity within each WARSS treatment group separately, after risk-factor adjustment (since these aPL-positive vs aPL-negative comparisons were not randomized).

RESULTS

Of the 1770 APASS patients, 720 (41%) were classified as aPL-positive and 1050 (59%) as aPL-negative. There was no increased risk of thrombo-occlusive events associated with baseline aPL status in patients treated with either warfarin (relative risk [RR], 0.99; 95% confidence interval [CI], 0.75-1.31; P =.94), or aspirin (RR, 0.94; 95% CI, 0.70-1.28; P =.71). The overall event rate was 22.2% among aPL-positive and 21.8% among aPL-negative patients. There was no treatment x aPL interaction (P =.91). Patients with baseline positivity for both LA and aCL antibodies tended to have a higher event rate (31.7%) than did patients who tested negative for both antibodies (24.0%) (unadjusted RR, 1.36; 95% CI, 0.97-1.92; P =.07). Classification and regression tree analyses did not identify a specific LA test or aCL isotype or titer that was associated with increased risk of thrombo-occlusive event.

CONCLUSIONS

The presence of aPL (either LA or aCL) among patients with ischemic stroke does not predict either increased risk for subsequent vascular occlusive events over 2 years or a differential response to aspirin or warfarin therapy. Routine screening for aPL in patients with ischemic stroke does not appear warranted.

Regulation of auxin transport by aminopeptidases and endogenous flavonoids

The 1-N-naphthylphthalamic acid (NPA)-binding protein is a putative negative regulator of polar auxin transport that has been shown to block auxin efflux from both whole plant tissues and microsomal membrane vesicles. We previously showed that NPA is hydrolyzed by plasma-membrane amidohydrolases that co-localize with tyrosine, proline, and tryptophan-specific aminopeptidases (APs) in the cotyledonary node, hypocotyl-root transition zone and root distal elongation zone of Arabidopsis thaliana (L.) Heynh. seedlings. Moreover, amino acyl-beta-naphthylamide (aa-NA) conjugates resembling NPA in structure have NPA-like inhibitory activity on growth, suggesting a possible role of APs in NPA action. Here we report that the same aa-NA conjugates and the AP inhibitor bestatin also block auxin efflux from seedling tissue. Bestatin and, to a lesser extent, some aa-NA conjugates were more effective inhibitors of low-affinity specific [3H]NPA-binding than were the flavonoids quercetin and kaempferol but had no effect on high-affinity binding. Since the APs are inhibited by flavonoids, we compared the localization of endogenous flavonoids and APs in seedling tissue. A correlation between AP and flavonoid localization was found in 5- to 6-d-old seedlings. Evidence that these flavonoids regulate auxin accumulation in vivo was obtained using the flavonoid-deficient mutant, tt4. In whole-seedling [14C]indole-3-acetic acid transport studies, the pattern of auxin distribution in the tt4 mutant was shown to be altered. The defect appeared to be in auxin accumulation, as a considerable amount of auxin escaped from the roots. Treatment of the tt4 mutant with the missing intermediate naringenin restored normal auxin distribution and accumulation by the root. These results implicate APs and endogenous flavonoids in the regulation of auxin efflux.

High multidrug resistance (P-glycoprotein 170) expression in inflammatory bowel disease patients who fail medical therapy

BACKGROUND & AIMS

The multidrug resistance (MDR) gene codes for a drug efflux pump P-glycoprotein 170 (Pgp-170) expressed on the surface of lymphocytes and intestinal epithelial cells. Inflammatory bowel disease (IBD) poorly responsive to medical therapy may relate to MDR expression because glucocorticoids are known Pgp-170 substrates.

METHODS

Using flow cytometry, we measured peripheral blood lymphocyte (PBL) MDR in 153 IBD patients and 50 healthy volunteers, and assessed the relationship between PBL, mucosal intraepithelial lymphocyte (IEL), and mucosal epithelial cell (EC) MDR expression in a further 20 IBD patients and 19 controls.

RESULTS

Compared with controls, PBL MDR was significantly elevated in patients with Crohn's disease who required bowel resection for failed medical therapy (mean +/- SEM, 26.7 +/- 2.8 vs. 11.9 +/- 1.0; P <0.0001) and patients with ulcerative colitis who required proctocolectomy for failed medical therapy (20.3 +/- 2.5 vs. 11.9 +/- 1.0; P = 0.001). PBL MDR remained stable over time and was not influenced by disease activity or glucocorticoid therapy. Both PBL and mucosal MDR expression appeared independent of disease activity, and there was a significant correlation between PBL MDR expression and both IEL expression (r = 0.92; P < 0.0001) and EC expression (r = 0.54; P < 0.001).

CONCLUSIONS

PBL and mucosal MDR expression may play an important role in determining the response of IBD patients to glucocorticoid therapy.

Influence of surgical margins on outcome in patients with preoperatively irradiated extremity soft tissue sarcomas

BACKGROUND

Limb-sparing surgery for soft tissue sarcomas of the extremities may result in microscopically positive surgical margins. The consequences of these microscopically positive margins are unknown. We have analyzed the influence of surgical margins on local disease control and overall survival in patients with extremity soft tissue sarcomas who received preoperative radiation therapy followed by limb-sparing surgery.

METHODS

Ninety-five consecutive patients with intermediate and high grade extremity sarcomas who received preoperative radiation therapy and limb-sparing surgery were identified from a soft tissue sarcoma data-base. The clinical outcome of 24 patients who had microscopically positive surgical margins was compared with that of 71 patients who had clear surgical margins.

RESULTS

Multivariate statistical analysis revealed that patients with microscopically positive surgical margins or intraoperative tumor violation had an increased risk for local failure. High grade, large size, and intraoperative violation of the tumors were associated with decreased overall survival. However, neither the presence of a positive surgical margin nor the occurrence of a local failure adversely affected overall survival.

CONCLUSIONS

Achieving negative surgical margins in patients with intermediate and high grade extremity sarcomas enhances local disease control but does not measurably improve overall survival. These data should be factored into patient management decisions in cases where the goal of achieving clear surgical margins requires amputation or the significant functional compromise of the extremity.

The infant whiplash-shake injury syndrome: a clinical and pathological study

The cases of 13 infants (median age, 3 months) who sustained nonaccidental trauma were reviewed. All presented with profound neurological impairment, seizures, retinal hemorrhages, and intracranial subarachnoid and/or subdural hemorrhages. Of 8 infants who died, autopsy was performed on 6. No patient had a skull fracture, and only one had an extracalvarial contusion. Five of the 6 patients on whom autopsy was performed had injuries at the cervicomedullary junction consisting of sub- or epidural hematomas of the cervical spinal cord with proximal spinal cord contusions. The authors conclude that direct cranial trauma is not an essential element of the injury mechanism in young patients who sustain severe whiplash-shake injuries. In addition to the classic injuries reported to occur with the shaken-baby syndrome, hemorrhages and contusions of the high cervical spinal cord may contribute to morbidity and mortality.

Mitochondrial oxidative phosphorylation is a downstream regulator of nitric oxide effects on chondrocyte matrix synthesis and mineralization

OBJECTIVE

Increased chondrocyte nitric oxide (NO) and peroxynitrite production appears to modulate decreased matrix synthesis and increased mineralization in osteoarthritis (OA). Because NO inhibits mitochondrial respiration, this study was undertaken to directly assess the potential role of chondrocyte mitochondrial oxidative phosphorylation (OXPHOS) in matrix synthesis and mineralization.

METHODS

We studied cultured human articular chondrocytes and immortalized costal chondrocytes (TC28 cells). We also assessed the effects of antimycin A and oligomycin (inhibitors of mitochondrial complexes III and V, respectively) on chondrocyte mitochondrial respiration, ATP synthesis, and inorganic pyrophosphate (PPi) generation, and the mineralizing potential of released matrix vesicles (MV).

RESULTS

Articular chondrocytes and TC28 cells respired at comparable rates. Peroxynitrite and NO donors markedly suppressed respiration and ATP generation in chondrocytes. Because NO exerts multiple effects on chondrocytes, we investigated the primary functions of mitochondrial respiration and OXPHOS. To do so, we identified minimally cytotoxic doses of antimycin and oligomycin, which both induced intracellular ATP depletion (by 50-80%), attenuated collagen and proteoglycan synthesis, and blocked transforming growth factor beta from increasing intracellular ATP and elaboration of PPi, a critical inhibitor of hydroxyapatite deposition. Antimycin and oligomycin also abrogated the ability of the ATP-hydrolyzing enzyme plasma cell membrane glycoprotein 1 (PC-1) to increase chondrocyte PPi generation. Finally, MV from cells treated with antimycin or oligomycin contained less PPi and precipitated >50% more 45Ca.

CONCLUSION

Chondrocyte mitochondrial reserve, as NO-sensitive mitochondrial respiration-mediated ATP production, appears to support matrix synthesis and PPi elaboration and to regulate MV composition and mineralizing activity. NO-induced depression of chondrocyte respiration could modulate matrix loss and secondary cartilage mineralization in OA.

Changes in Selected Biochemical, Muscular Strength, Power, and Endurance Measures during Deliberate Overreaching and Tapering in Rugby League Players

The purpose of this study was to examine the influence of overreaching on muscle strength, power, endurance and selected biochemical responses in rugby league players. Seven semi-professional rugby league players (.VO(2max) = 56.1 +/- 1.7 mL . kg (-1) . min (-1); age = 25.7 +/- 2.6 yr; BMI = 27.6 +/- 2.0) completed 6 weeks of progressive overload training with limited recovery periods. A short 7-day stepwise reduction taper immediately followed the overload period. Measures of muscular strength, power and endurance and selected biochemical parameters were taken before and after overload training and taper. Multistage fitness test running performance was significantly reduced (12.3 %) following the overload period. Although most other performance measures tended to decrease following the overload period, only peak hamstring torque at 1.05 rad . s (-1) was significantly reduced (p < 0.05). Following the taper, a significant increase in peak hamstring torque and isokinetic work at both slow (1.05 rad . s (-1)) and fast (5.25 rad . s (-1)) movement velocities were observed. Minimum clinically important performance decreases were measured in a multistage fitness test, vertical jump, 3-RM squat and 3-RM bench press and chin-up (max) following the overload period. Following the taper, minimum clinically important increases in the multistage fitness test, vertical jump, 3-RM squat and 3-RM bench press and chin-up (max) and 10-m sprint performance were observed. Compared to resting measures, the plasma testosterone to cortisol ratio, plasma glutamate, plasma glutamine to glutamate ratio and plasma creatine kinase activity demonstrated significant changes at the end of the overload training period (p < 0.05). These results suggest that muscular strength, power and endurance were reduced following the overload training, indicating a state of overreaching. The most likely explanation for the decreased performance is increased muscle damage via a decrease in the anabolic-catabolic balance.

Thrombospondin promotes cell-substratum adhesion

The physiological role of the platelet-secreted protein thrombospondin (TSP) is poorly understood, although it has been postulated to be involved in platelet aggregation and cellular adhesion. In this report, TSP isolated from human platelets was found to promote, in vitro, the cell-substratum adhesion of a variety of cells, including platelets, melanoma cells, muscle cells, endothelial cells, fibroblasts, and epithelial cells. The adhesion-promoting activity of TSP was species independent, specific, and not due to contamination by fibronectin, vitronectin, laminin, or platelet factor 4. The cell surface receptor for TSP is protein in nature and appears distinct from that for fibronectin.

Effects of menstrual-cycle hormone fluctuations on musculotendinous stiffness and knee joint laxity

The high risk of anterior cruciate ligament (ACL) injuries in female athletes may be related to hormonal fluctuations resulting in an increased laxity of ligaments and muscles. This study examined changes in lower limb musculotendinous stiffness (MTS) and knee laxity over the course of the menstrual cycle and investigated the interaction of warm-up on MTS. Eleven female netball players aged 16-18 years who were not using hormonal contraceptives and demonstrated regular menstrual cycles participated in this study. Test-sessions were conducted at onset of menses, mid-follicular phase, ovulation and mid-luteal phase. ACL laxity was determined at each test-session using a KT2000 knee arthrometer. MTS was assessed prior to, and following a standardised warm-up. Repeated measures ANOVA revealed significant (P < 0.05) main effects of test-session and warm-up on MTS. MTS was found to significantly decrease by 4.2% following the warm-up intervention. MTS was significantly lower at week 3 (ovulatory phase) in contrast to weeks 1 and 2 (8.7 and 4.5%, respectively). For knee laxity measures, repeated measures ANOVA revealed no significant (P < 0.05) differences across the menstrual cycle. A reduction in MTS results in greater reliance on reflexive response from the contractile components of the muscle due to a decreased contribution from passive elastic structures and will also increase electromechanical delay. Given that extreme loads are applied to the knee joint within milliseconds, the contractile components cannot respond quickly enough to counteract these sudden and potentially damaging forces. These effects are augmented following a moderate warm-up. Oestrogen fluctuations had no significant effect on anterior knee laxity, however, the effects on MTS over the 28-day cycle were considerable. Future studies should use matched subjects who are using the monophasic oral contraceptive pill to investigate the effects of oestrogen supplementation on lower limb MTS.

Variation between experienced observers in the interpretation of accident and emergency radiographs

Skill mix and role extension initiatives have highlighted the difficulty of establishing quality standards for the accuracy of plain film reporting. An acceptable performance might be one which is indistinguishable from that of a group of experienced consultant radiologists. In order to assess the feasibility of setting such a standard, the variation between experienced observers must first be established. This study examines the variation found between three observers with the three major types of plain film examination. 402 plain film examinations (205 skeletal, 100 chest and 97 abdominal) performed on accident and emergency patients were reported retrospectively and independently by three experienced radiologists. The clinical data supplied on the request cards were available to the readers. Each examination was categorized by each reader as being normal, as showing significant abnormality relevant to the current clinical problem, or as showing insignificant or irrelevant abnormality. Concordance between all three readers was found in 51%, 61% and 74% of abdominal, chest and skeletal radiographs, respectively. Weighted kappa values confirmed that the level of agreement between pairs of observers was higher with skeletal radiographs (kappa w = 0.76-0.77) than with chest (kappa w = 0.63-0.68), or abdominal (kappa w = 0.50-0.78) examinations. However, the frequency of major disagreements (at least one reader reporting "normal" and one reporting "relevant abnormality") was similar for abdominal (11%), chest (12%) and skeletal (10%) radiographs. When the reports were reclassified into only two groups--either significantly abnormal or not--pairs of observers disagreed on 9-10% of skeletal, 11-19% of chest and 8-18% of abdominal cases. The average incidence of errors per observer was estimated to be in the range 3-6%. The magnitude of interobserver variation in plain film reporting is considerable, and must be taken into account when designing assessment techniques and setting quality standards for this activity.

Comparison of metallothionein gene expression and nonprotein thiols in ten Arabidopsis ecotypes. Correlation with copper tolerance

Seedlings of 10 Arabidopsis ecotypes were compared with respect to copper tolerance, expression of two metallothionein genes (MT1 and MT2), and nonprotein thiol levels. MT1 was uniformly expressed in all treatments, and MT2 was copper inducible in all 10 ecotypes. MT1 and MT2 mRNA levels were compared with various growth parameters for the 10 ecotypes in the presence of 40 microM Cu2+. The best correlation (R = 0.99) was obtained between MT2 mRNA and the rate of root extension. MT2 mRNA levels also paralleled the recovery phase following inhibition by copper. Induction of MT2 mRNA was initiated at copper concentrations below the threshold for growth inhibition. In cross-induction experiments, Ag+, Cd2+, Zn2+, Ni2+, and heat shock all induced significant levels of MT2 gene expression, whereas Al3+ and salicylic acid did not. The correlation between copper tolerance and nonprotein thiol levels in the 10 ecotypes was not statistically significant. However, 2 ecotypes, Ws and Enkheim, previously shown to exhibit an acclimation response, had the highest levels of nonprotein thiols. We conclude that MT2 gene expression may be the primary determinant of ecotypic differences in the copper tolerance of nonpretreated Arabidopsis seedlings.

Neurofibromatosis: clinical presentations and anaesthetic implications

The neurofibromatoses are autosomal dominant diseases that have widespread effects on ectodermal and mesodermal tissue. The commonest member of the group is neurofibromatosis type 1 (NF1) which varies in severity but which can affect all physiological systems. Neurofibromas are the characteristic lesions of the condition and not only occur in the neuraxis but may also be found in the oropharnyx and larynx; these may produce difficulties with laryngoscopy and tracheal intubation. Pulmonary pathology includes pulmonary fibrosis and cystic lung disease. The cardiovascular manifestations of NF1 include hypertension, which may be associated with phaeochromocytoma or renal artery stenosis. Neurofibromas may also affect the gastrointestinal tract and carcinoid tumours may be found in the duodenum. This review documents the aetiology and clinical manifestations of the neurofibromatoses and discusses their relevance to the anaesthetist.

Molecular pathology of prostate cancer

The molecular pathology of prostate cancer is complex; not only are multiple genes involved in its pathogenesis, but additional environmental factors such as diet and inflammation are also involved. The exhaustive research into prostate cancer to date has demonstrated a complex interaction of multiple genes and environmental factors, some of which may be more important in individual prostate cancer cases. This is an exciting era, with the emergence of new investigative tools such as DNA microarray technology and the application of the field of proteomics to the study of human cancers. Knowledge of genetic changes underlying the initiation, development, and progression of prostate cancer is accumulating rapidly. With increasing knowledge, it may be possible to distinguish indolent from aggressive prostate tumours by molecular fingerprinting. This review discusses the most consistently reported molecular pathological findings in hereditary and sporadic prostate cancer, together with new concepts and technologies.

The CCR5-delta32 mutation: impact on disease outcome in individuals with hepatitis C infection from a single source

BACKGROUND AND AIMS

Chemokines are small polypeptides, a major function of which is lymphocyte recruitment and trafficking. The aim of this study was to assess the involvement of inherited variations in CCR2, CCR5, and the ligand RANTES in determining disease outcome in hepatitis C virus (HCV) infected individuals.

METHODS

A total of 283 women, all exposed to HCV genotype 1b from a single donor, and including those who had spontaneously cleared the virus and those chronically infected, were genotyped for CCR2, CCR5, and RANTES polymorphisms. The frequencies of these polymorphisms were then compared with disease activity and severity.

RESULTS

CCR5, CCR2, and RANTES genotypes were compared with HCV polymerase chain reaction (PCR) status, alanine aminotransferase levels, and liver histology. There was no significant relationship between CCR2 or RANTES polymorphisms and disease outcome or severity. However, CCR5delta32 heterozygotes were more likely to have spontaneous clearance of the virus than those without the mutation (42% PCR negative v 28.3% negative; p = 0.044, odds ratio 1.83 (95% confidence interval 1.1-3.6)). Among the subgroup of DRB1*03011 negative individuals, previously found to be associated with more severe inflammation, the difference in histological inflammatory score (CCR5WT/WT = 4.9 v CCR5delta32/WT = 3.53; p = 0.043) was significant.

CONCLUSION

Heterozygosity for CCR5delta32 was shown to be significantly associated with spontaneous hepatitis C viral clearance and with significantly lower hepatic inflammatory scores in subgroups within this cohort. Both controls and the HCV population had similar heterozygosity frequencies.

Optical nonlocalities and additional waves in epsilon-near-zero metamaterials

We analyze the optical properties of plasmonic nanorod metamaterials in the epsilon-near-zero regime and show, both theoretically and experimentally, that the performance of these composites is strongly affected by nonlocal response of the effective permittivity tensor. We provide the evidence of interference between main and additional waves propagating in the room-temperature nanorod metamaterials and develop an analytical description of this phenomenon. Additional waves are present in the majority of low-loss epsilon-near-zero structures and should be explicitly considered when designing applications of epsilon-near-zero composites, as they represent a separate communication channel.

Metallothioneins 1 and 2 have distinct but overlapping expression patterns in Arabidopsis

The spatial and temporal expression patterns of metallothionein (MT) isoforms MT1a and MT2a were investigated in vegetative and reproductive tissues of untreated and copper-treated Arabidopsis by in situ hybridization and by northern blotting. In control plants, MT1a mRNA was localized in leaf trichomes and in the vascular tissue in leaves, roots, flowers, and germinating embryos. In copper-treated plants, MT1a expression was also observed in the leaf mesophyll and in vascular tissue of developing siliques and seeds. In contrast, MT2a was expressed primarily in the trichomes of both untreated and copper-treated plants. In copper-treated plants, MT2a mRNA was also expressed in siliques. Northern-hybridization studies performed on developing seedlings and leaves showed temporal variations of MT1a gene expression but not of MT2a expression. The possible implications of these findings for the cellular roles of MTs in plants are discussed.

Anxiogenic profile of AM-251, a selective cannabinoid CB1 receptor antagonist, in plus-maze-na??ve and plus-maze-experienced mice

The notoriously inconsistent effects of cannabinoids on anxiety-like behaviour may be explained by recent research on CB1 receptor knockout (CB1-KO) mice suggesting that cannabinoids exert bidirectional effects via the CB1 receptor (anxiolysis) and a novel rimonabant-sensitive neuronal cannabinoid receptor (anxiogenesis). This hypothesis is supported by the anxiogenic-like profile of AM-251, an analogue of rimonabant that is a potent and selective CB1 receptor antagonist but which, unlike rimonabant, has no activity at the novel receptor. As we have previously shown that rimonabant reduces anxiety-like behaviour in test-experienced animals only, the current study assessed the effects of AM-251 (1.5-3.0 mg/kg) in male Swiss-Webster mice that were either plus-maze-naïve or had been exposed undrugged to the apparatus 24 h prior to testing. Results confirmed that prior maze experience per se significantly increases behavioural indices of anxiety without altering measures of general activity. In maze-naïve mice, the lower dose of AM-251 (1.5 mg/kg) significantly reduced % open-arm time and increased grooming while the higher dose (3.0 mg/kg) additionally reduced open-arm entries and total head-dipping, and increased closed-arm returns. These anxiogenic-like effects were observed in the absence of significant changes in general activity levels. Although AM-251 had a very similar profile in maze-experienced animals, significant drug effects on open-arm avoidance measures were precluded by experientially-induced changes in behavioural baselines (i.e. 'ceiling' effects). Nevertheless, AM-251 again significantly reduced total head-dipping and increased grooming (3.0 mg/kg) and, unlike effects in naïve animals, both doses markedly reduced time spent on the centre platform and increased time spent in the enclosed arms. Against a baseline of almost total open-arm avoidance, the pattern of behavioural change in maze-experienced mice would also be consistent with an anxiogenic-like action of AM-251. Data are discussed in relation to previous findings with rimonabant, the putative existence of a novel non-CB1 neuronal cannabinoid receptor and, more generally, the behavioural pharmacology of plus-maze 'trial 2'.

Spectrophotometric quantitation of anchorage-dependent cell numbers using the bicinchoninic acid protein assay reagent

A rapid and convenient method is described for the determination of the actual and relative number of adherent cells in tissue culture. The cell lines human melanoma C32, ATCC CRL 1585, mouse melanoma B16-F10, and pig epithelial LLC-PK1, suspended in Dulbecco's minimum essential medium containing no serum, were allowed to adhere to fibronectin adsorbed to wells of a 96-well microtiter plate. Nonadherent cells were removed by aspiration, wells were washed, and adherent cells were solubilized with 200 microliters of the bicinchoninic acid (4,4'-dicarboxy-2,2'-biquinoline) protein assay reagent. Plates were heated to 60 degrees C for 30 min and absorbances read at 562 nm using a microtiter plate reader. A linear correlation was observed between the number of adherent cells in the range 2-8 X 10(5)/ml cells added and the protein content of the adherent cells as measured by the BCA protein reagent. The assay procedure gave absorbance values in the range of 0.100 to 1.30 making the method highly sensitive and reproducible. Blank wells containing only coupled protein and no cells gave little or no absorbance. Cell adhesion was fibronectin specific since little or no cell attachment was observed when microtiter plates were coupled with bovine serum albumin. Similar results were obtained with other cell types such as platelets. These results indicate that measurement of total cellular protein using the BCA protein reagent can be a rapid and sensitive assay for the detection and quantitation of adherent cells.

Bombesin-like peptides elevate cytosolic calcium in small cell lung cancer cells

The ability of bombesin-like peptides to elevate intracellular Ca2+ levels in small cell lung cancer cells was investigated using the fluorescent Ca2+ indicator Fura 2. Nanomolar concentrations of bombesin elevated cytosolic Ca2+ levels in the absence or presence of extracellular Ca2+. Potent bombesin receptor agonists, such as gastrin releasing peptide (GRP) or (GRP)14-27 elevated cytosolic Ca2+ levels whereas inactive compounds such as (D-Trp8)bombesin or (GRP)1-16 did not. Furthermore, the bombesin receptor antagonist (D-Arg1, D-Pro2, D-Trp7,9, Leu11) substance P (30 microM) had no effect on the Ca2+ levels by itself but antagonized the increase in Ca2+ caused by 10 nM or 100 nM bombesin. These data suggest that bombesin receptors may regulate the release of Ca2+ from intracellular organelles in small cell lung cancer cells.

Helicobacter pylori disrupts epithelial barrier function in a process inhibited by protein kinase C activators

Helicobacter pylori colonizes the gastric mucosa, and the infection is related to the development of diverse gastric pathologies, possibly by directly or indirectly affecting epithelial-cell function. We analyzed the influence of the bacteria on transepithelial electrical resistance (TER) on a model tight epithelium, T84, grown to confluence in permeable filters. H. pylori sonicates produced a dramatic decrease in TER after 1 to 2 h of exposure, while sonicates from other bacteria did not induce a significant reduction of TER. The effect induced by sonicates was mimicked by a water-soluble fraction from the bacterial surface, was not reproducible with isolated lipopolysaccharide, and was concomitant with a significant increase in the paracellular permeability of the marker molecule [14C]mannitol. Furthermore, H. pylori sonicates also provoked a significant increase in permeability to [14C]mannitol across rat gastric mucosa in vitro. The sonicate-induced decrease in TER in T84 monolayers was inhibited by the protein kinase C (PKC) activator phorbol myristate acetate. As PKC is directly involved in tight junction regulation, we suggest that H. pylori may induce intracellular signalling events counteracting PKC effects. Following long-term H. pylori stimulation, epithelial monolayers regained baseline resistance values slowly after 24 h. The resistance recovery process was inhibited by cycloheximide, indicating its dependency upon protein synthesis. No association between resistance variation and E-cadherin protein levels was observed. These results indicate that H. pylori alters in vitro the barrier properties of the epithelium, probably by generating cell signalling events counteracting the normal function of PKC. This increased permeability may provide a potential mechanism by which H. pylori antigens can reach the gastric lamina propria, thereby activating the mucosal immune system.

Purification and immunological identification of metallothioneins 1 and 2 from Arabidopsis thaliana

Gene families encoding two types of metallothioneins (MTs) MT1 and MT2, have been identified in Arabidopsis thaliana, and their respective mRNAs have been shown to be regulated by copper in a tissue-specific manner (J. Zhou and P.B. Goldsbrough [1994] Plant Cell 6: 875-884; J. Zhou and P.B. Goldsbrough [1995] Mol Gen Genet 248: 318-328; A.S. Murphy and L. Taiz [1995] Plant Physiol 109: 1-10). However, to date the protein products have not been identified. To purify MT proteins from Arabidopsis, we isolated low-molecular-mass, copper-binding, thiol-rich proteins using selective precipitation followed by size-exclusion, copper-affinity, and thiol-affinity chromatographies. Polyclonal antibodies raised against Arabidopsis MT-glutathione-S-transferase fusion proteins cross-reacted with the 4.5- and 8-kD bands in immunoblots of low-molecular-mass, copper-binding proteins purified from seedling, mature leaf, and mature root tissues. The identity of the proteins was subsequently confirmed by amino acid sequencing. MT1 expression was constitutive in roots and inducible by copper in mature leaves; the reverse pattern was observed for MT2. MT2 expression was also concentrated in the growing tip of the root. The accumulation of the MT1- and MT2-encoded proteins thus parallels the regulation of their respective mRNAs with regard to tissue specificity and induction by copper. In addition, a new type of MT, designated MT3, was derived from the database, detected by reverse transcription-polymerase chain reaction, and tentatively identified at the protein level by amino acid sequencing of a 7-kD cysteine-rich polypeptide.

Scaffold-Free Endometrial Organoids Respond to Excess Androgens Associated With Polycystic Ovarian Syndrome

CONTEXT

Polycystic ovary syndrome (PCOS) is a prevalent disorder in reproductive aged women associated with a number of endocrine and metabolic complications, including increased risk of endometrial cancer.

OBJECTIVE

To study the effect of the characteristic increased androgen levels in PCOS on the endometrium, a novel scaffold-free multicellular endometrial organoid was established.

DESIGN

Human endometrial organoids were constructed using primary endometrial epithelial and stromal cells from endometrial tissues. Organoids were treated for 14 days with physiologic levels of estradiol and testosterone to mimic a normal follicular phase or PCOS hormone profiles. Organoids were harvested for immunostaining and ribonucleic acid sequencing.

SETTING

Academic institution.

PATIENTS

Endometrial tissues from 10 premenopausal women undergoing hysterectomy for benign pathologies were obtained following written consent.

MAIN OUTCOME MEASURES

Organoid architecture, cell specific markers, functional markers, proliferation, and gene expression were measured.

RESULTS

A method to generate scaffold-free endometrial organoids containing epithelial and stromal cells was established. These organoids exhibited distinct organization with epithelial cells lining the outer surface and stromal cells in the center of the organoids. Epithelial cells were polarized, organoids expressed cell type specific and functional markers, as well as androgen, estrogen, and progesterone receptors. Treatment with PCOS hormones increased cell proliferation and dysregulated genes in endometrial organoids.

CONCLUSIONS

A new multicellular, scaffold-free endometrial organoid system was established that resembled physiology of the native endometrium. Excess androgens in PCOS promoted cell proliferation in endometrial organoids, revealing new mechanisms of PCOS-associated with risk of endometrial neoplasia.

Silver nanoparticles induce pro-inflammatory gene expression and inflammasome activation in human monocytes

A complete cytotoxic profile of exposure to silver (AgNP) nanoparticles investigating their biological effects on the innate immune response of circulating white blood cells is required to form a complete understanding of the risk posed. This was explored by measuring AgNP-stimulated gene expression of the pro-inflammatory cytokines interleukin-1 (IL-1), interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-α) in THP-1 monocytes. A further study, on human monocytes extracted from a cohort of blood samples, was carried out to compare with the AgNP immune response in THP-1 cells along with the detection of pro-IL-1β which is a key mediator of the inflammasome complex. The aims of the study were to clearly demonstrate that AgNP can significantly up-regulate pro-inflammatory cytokine gene expression of IL-1, IL-6 and TNF-α in both THP-1 cells and primary blood monocytes thus indicating a rapid response to AgNP in circulation. Furthermore, a role for the inflammasome in AgNP response was indicated by pro-IL-1β cleavage and release. These results highlight the potential inflammatory effects of AgNP exposure and the responses evoked should be considered with respect to the potential harm that exposure may cause. Copyright © 2016 John Wiley & Sons, Ltd.

Progesterone attenuates persistent inflammatory hyperalgesia in female rats: involvement of spinal NMDA receptor mechanisms

The relationship between endogenous gonadal steroid levels and persistent or chronic pain is poorly understood. These studies used an inflammation model to examine the role of the gonadal steroid, progesterone, in the development of persistent pain and hyperalgesia in lactating ovary-intact and ovariectomized rats. The results indicate that constant high plasma levels of progesterone attenuate inflammatory hyperalgesia by a mechanism involving inhibition of N-methyl-D-aspartate receptor activation at the spinal cord level. Since the pattern of high progesterone in lactating rats mimics the progesterone component of the luteal phase of the human menstrual cycle, these findings have significance in persistent or chronic pain conditions that are most prevalent in females.

Non-accidental fractures in infants: risk of further abuse

OBJECTIVES

To look for features of non-accidental fractures in infants aged under I year and assess the risk of subsequent morbidity and mortality.

METHODOLOGY

A retrospective analysis of 99 children aged under 1 year who presented to the Mater Children's Hospital, Brisbane, between January 1990 and December 1993, and were found to have a fracture. The 99 infants were divided into non-accidental and accidental groups. Comparison was made between the two groups for age, sex and type of fracture. Deaths, subsequent injuries and child protection notifications until March 1997 were compared between groups.

RESULTS

Of the 99 infants with fracture (64 males, 35 female), the skull and femur were the most prevalent sites of fracture. Twenty-six infants had fractures assessed as non-accidental. This group was younger but did not differ significantly in gender or site of fracture. Infants aged under 4 months had a significantly greater risk of their fracture being non-accidental (P = 0.0007). Subsequent substantiated child protection notifications occurred in nine of the non-accidental group and in one of the accidental group (P = 0.000001). There was no significant difference in the rate of subsequent notifications between those infants with abuse who were removed from their carers and those not removed. Subsequent injuries presenting to hospital occurred in 17 of the accidental group and three of the non-accidental group (P = 0.20). There were no deaths.

CONCLUSION

Infants aged under 1 year with fractures have a high prevalence of abuse. The risk of abuse as cause for the fracture is greater in those aged under 4 months. Infants with non-accidental fractures have a high risk of further abuse even with intervention.