An evolutionarily conserved phosphoserine-arginine salt bridge in the interface between ribosomal proteins uS4 and uS5 regulates translational accuracy in Saccharomyces cerevisiae

Protein-protein and protein-rRNA interactions at the interface between ribosomal proteins uS4 and uS5 are thought to maintain the accuracy of protein synthesis by increasing selection of cognate aminoacyl-tRNAs. Selection involves a major conformational change-domain closure-that stabilizes aminoacyl-tRNA in the ribosomal acceptor (A) site. This has been thought a constitutive function of the ribosome ensuring consistent accuracy. Recently, the Saccharomyces cerevisiae Ctk1 cyclin-dependent kinase was demonstrated to ensure translational accuracy and Ser238 of uS5 proposed as its target. Surprisingly, Ser238 is outside the uS4-uS5 interface and no obvious mechanism has been proposed to explain its role. We show that the true target of Ctk1 regulation is another uS5 residue, Ser176, which lies in the interface opposite to Arg57 of uS4. Based on site specific mutagenesis, we propose that phospho-Ser176 forms a salt bridge with Arg57, which should increase selectivity by strengthening the interface. Genetic data show that Ctk1 regulates accuracy indirectly; the data suggest that the kinase Ypk2 directly phosphorylates Ser176. A second kinase pathway involving TORC1 and Pkc1 can inhibit this effect. The level of accuracy appears to depend on competitive action of these two pathways to regulate the level of Ser176 phosphorylation.

Posttranscriptional modification to the core of tRNAs modulates translational misreading errors

Protein synthesis on the ribosome involves successive rapid recruitment of cognate aminoacyl-tRNAs and rejection of the much more numerous incorrect near- or non-cognates. The principal feature of translation elongation is that at every step, many incorrect aa-tRNAs unsuccessfully enter the A site for each cognate accepted. Normal levels of translational accuracy require that cognate tRNAs have relatively similar acceptance rates by the ribosome. To achieve that, tRNAs evolved to compensate for differences in amino acid properties and codon-anticodon strength that affect acceptance. Part of that response involved tRNA posttranscriptional modifications, which can affect tRNA decoding efficiency, accuracy, and structural stability. The most intensively modified regions of the tRNA are the anticodon loop and structural core of the tRNA. Anticodon loop modifications directly affect codon-anticodon pairing and therefore modulate accuracy. Core modifications have been thought to ensure consistent decoding rates principally by stabilizing tRNA structure to avoid degradation; however, degradation due to instability appears to only be a significant issue above normal growth temperatures. We suspected that the greater role of modification at normal temperatures might be to tune tRNAs to maintain consistent intrinsic rates of acceptance and peptide transfer and that hypomodification by altering these rates might degrade the process of discrimination, leading to increased translational errors. Here, we present evidence that most tRNA core modifications do modulate the frequency of misreading errors, suggesting that the need to maintain accuracy explains their deep evolutionary conservation.

Differential Corticospinal Excitability and Cortical Functional Connectivity Modulation by Spinal Cord Transcutaneous Stimulation-based Motor Training versus Motor Training alone in Able-bodied and SCI participants: A Multiple Case Study

Spinal cord transcutaneous stimulation (scTS) has shown its potential for boosting motor, sensory, and autonomic function recovery after a spinal cord injury. Despite the demonstrated benefits, little is known about the exact neuromodulatory mechanisms triggered by scTS and the cortex involvement in the beneficial effects observed. Here, we examine the effects of scTS-based motor training and motor training alone on sensorimotor cortical functional connectivity and corticospinal excitability in able-bodied and SCI participants.Clinical Relevance- The results show preliminary evidence of differential cortical involvement and modulation by scTS-based motor training in uninjured and spinal-cord injured individuals. A better understanding of scTS mechanisms of action could help optimize the intervention design and potentiate its benefits.

Neglected congenital trigger thumb

We present a case of neglected trigger thumb in a forty-year-old male. The patient presented to our clinic due to bilateral triggering of his fourth digit. He attested to having pain and limitation of joint movement of his left thumb since his childhood in the former Soviet Union, with occasional triggering. This eventually subsided and the thumb became stuck in relative flexion and could not be fully extended. We performed X-rays of both thumbs wherein the left affected thumb interphalangeal joint showed an aberrant configuration and sclerosis of both joint surfaces. The joint surface curvature was altered on the left side and contact area reduced. This presentation of altered thumb interphalangeal joint biomechanics following an untreated congenital trigger thumb further emphasizes the need for surgical intervention when indicated.

Consensus statement on measures to promote equitable authorship in the publication of research from international partnerships

Despite the acknowledged injustice and widespread existence of parachute research studies conducted in low‐ or middle‐income countries by researchers from institutions in high‐income countries, there is currently no pragmatic guidance for how academic journals should evaluate manuscript submissions and challenge this practice. We assembled a multidisciplinary group of editors and researchers with expertise in international health research to develop this consensus statement. We reviewed relevant existing literature and held three workshops to present research data and holistically discuss the concept of equitable authorship and the role of academic journals in the context of international health research partnerships. We subsequently developed statements to guide prospective authors and journal editors as to how they should address this issue. We recommend that for manuscripts that report research conducted in low‐ or middle‐income countries by collaborations including partners from one or more high‐income countries, authors should submit accompanying structured reflexivity statements. We provide specific questions that these statements should address and suggest that journals should transparently publish reflexivity statements with accepted manuscripts. We also provide guidance to journal editors about how they should assess the structured statements when making decisions on whether to accept or reject submitted manuscripts. We urge journals across disciplines to adopt these recommendations to accelerate the changes needed to halt the practice of parachute research.

Air pollution interventions and respiratory health: a systematic review

BACKGROUND: Indoor and ambient air pollution exposure is a major risk to respiratory health worldwide, particularly in low- and middle-income countries (LMICs). Interventional trials have mainly focused on alternatives to cooking stoves, with mixed results. Beyond cooking, additional sources of particulate matter also contribute to the burden of air pollution exposure. This review explores evidence from current randomised controlled trials (RCTs) on the clinical effectiveness of interventions to reduce particulate matter in LMICs.METHODS: Twelve databases and the grey literature (e.g., Government reports and policy papers) were searched. Eligible studies were RCTs conducted in LMICs aiming to reduce particulate exposure from any source and reporting on at least one clinical respiratory outcome (respiratory symptoms, lung function or clinical diagnoses). Data from relevant studies were systematically extracted, the risk of bias assessed and narrative synthesis provided.RESULTS: Of the 14 included studies, 12 tested 'improved' cookstoves, most using biomass, but solar and bioethanol cookers were also included. One trial used solar lamps and another was an integrated intervention incorporating behavioural and environmental components for the treatment and prevention of chronic obstructive pulmonary disease. Of the six studies reporting child pneumonia outcomes, none demonstrated significant benefit in intention-to-treat analysis. Ten studies reported respiratory symptom outcomes with some improvements seen, but self-reporting made these outcomes highly vulnerable to bias. Substantial inter-study clinical and methodological heterogeneity precluded calculation of pooled effect estimates.CONCLUSION: Evidence from the RCTs performed to date suggests that individual household-level interventions for air pollution exposure reduction have limited benefits for respiratory health. More comprehensive approaches to air pollution exposure reduction must be developed so their potential health benefits can be assessed.

Early intervention with probiotics and metformin alleviates liver injury in NAFLD rats via targeting gut microbiota dysbiosis and p-AKT/mTOR/LC-3II pathways

Non-alcoholic fatty liver disease (NAFLD) constitutes a major health problem worldwide and intimately links with obesity and diabetes. This study aimed to explore the therapeutic impact of early treatment with metformin (MTF) alone or in combination with Lactobacillus reuteri DSM 17938 (L. reuteri) + metronidazole (MTZ) in male Sprague Dawley rats with high-fat diet (HFD)-induced NAFLD. Hepatic steatosis was induced by feeding rats HFD for 6 weeks. MTF (150 mg/kg/day) or L. reuteri (2 × 10⁹ colony forming unit/day) were given orally for 4 weeks; meanwhile, MTZ (15 mg/kg/day, p.o.) was administered for 1 week. Administration of L. reuteri + MTZ in combination with MTF produced a superior effect concerning insulin resistance (IR), lipid profile, liver function, oxidative stress, inflammatory and autophagic markers than using each treatment alone. Besides, this combination resulted in disappearance of steatosis, inflammation and vacuolation within hepatic architecture. Moreover, it normalized short chain fatty acids (SCFAs) as well as Firmicutes and Bacteroidetes faecal contents. In conclusion, early treatment with L. reuteri + MTZ in combination with MTF could prevent NAFLD progression and liver injury through targeting gut dysbiosis, inflammation and autophagic pathways.

Ovarian gastrointestinal stromal tumor: does this diagnosis exist?

Gastrointestinal stromal tumors (GISTs) are rare gastrointestinal (GI ) tract tumors. Those tumors rarely arise extra intestinally; within omentum, mesentery, and rarely uterus. The authors report a case of myxoid variant of GIST arising in the ovary with no evidence of a primary tumor in the GI tract. Surgeons as well as gynecologists should bear this possibility in mind when managing pelvic masses.

Osteopontin regulates proliferation, apoptosis, and migration of murine claudin-low mammary tumor cells

Background

Osteopontin is a secreted phosphoglycoprotein that is expressed by a number of normal cells as well as a variety of tumor cells. With respect to breast cancer, osteopontin has been implicated in regulating tumor cell proliferation and migration/metastasis and may serve as a prognostic indicator. However it remains unclear whether osteopontin has the same impact in all breast cancer subtypes and in particular, osteopontin’s effects in claudin-low breast cancer are poorly understood.

Methods

cDNA microarrays and qRT-PCR were used to evaluate osteopontin expression in mammary tumors from MTB-IGFIR transgenic mice and cell lines derived from these tumors. siRNA was then used to determine the impact of osteopontin knockdown on proliferation, apoptosis and migration in vitro in two murine claudin-low cell lines as well as identify the receptor mediating osteopontin’s physiologic effects.

Results

Osteopontin was expressed at high levels in mammary tumors derived from MTB-IGFIR transgenic mice compared to normal mammary tissue. Evaluation of cell lines derived from different mammary tumors revealed that mammary tumor cells with claudin-low characteristic expressed high levels of osteopontin whereas mammary tumor cells with mixed luminal and basal-like features expressed lower levels of osteopontin. Reduction of osteopontin levels using siRNA significantly reduced proliferation and migration while increasing apoptosis in the claudin-low cell lines. Osteopontin’s effect appear to be mediated through a receptor containing ITGAV and not through CD44.

Conclusions

Our data suggests that mammary tumors with a mixed luminal/basal-like phenotype express high levels of osteopontin however this osteopontin appears to be largely produced by non-tumor cells in the tumor microenvironment. In contrast tumor cells with claudin-low characteristics express high levels of osteopontin and a reduction of osteopontin in these cells impaired proliferation, survival and migration.

Association between payer mix and costs, revenues and profitability: a cross-sectional study of Lebanese hospitals

This study aimed to examine the association between the payer mix and the financial performance of public and private hospitals in Lebanon. The sample comprised 24 hospitals, representing the variety of hospital characteristics in Lebanon. The distribution of the payer mix revealed that the main sources of revenue were public sources (61.1%), out-of-pocket (18.4%) and private insurance (18.2%). Increases in the percentage of revenue from public sources were associated with lower total costs and revenues, but not profit margins. An inverse association was noted between increased revenue from private insurance and profitability, attributed to increased costs. Increased percentage of out of- pocket payments was associated with lower costs and higher profitability. The study provides evidence that payer mix is associated with hospital costs, revenues and profitability. This should initiate/inform discussions between public and private payers and hospitals about the level of payment and its association with hospital sector financial viability.

Being suckled in a large litter mitigates the effects of early-life stress on hypothalamic-pituitary-adrenal axis function in the male rat

The perinatal environment influences stress responses in the long-term, as does body composition. Male rats suckled in large litters, where they have reduced access to milk and attention from the dam, are less anxious and have attenuated hypothalamic-pituitary-adrenal (HPA) axis responses to stress compared to rats from control litters. In the present study, we investigated whether this early-life environment can also ameliorate anxiety and HPA axis function in rats prone to be stress-sensitive. We conducted these experiments in male rats from control litters (n = 12) or large litters (n = 20). Half were given 24 h of maternal separation on postnatal day 10 to induce HPA axis hyperactivity; the remainder staying undisturbed with their dam. When the rats reached adulthood, we examined behavioural indices of anxiety (elevated plus maze) and depression (Porsolt's forced swim test) under basal conditions and after 15 min of restraint stress. We also examined neuronal activation in the paraventricular nucleus of the hypothalamus (PVN) as an index of HPA axis function. Being suckled in a large litter led to a significantly attenuated PVN response to stress in adulthood. Maternal separation strongly exacerbated the stress-induced increase in PVN neuronal activation in control rats but did not affect the PVN response in large-litter rats. Immobility in the forced swim after restraint was also exacerbated in neonatally maternally separated control rats but not in those from large litters. Our findings show that being suckled in large litters mitigates the effects of early-life stress on HPA axis function and indices of depression in the rat.

Effect of school based treatment on the prevalence of schistosomiasis in endemic area in yemen

BACKGROUND

Schistosomiasis and soil transmitted infection is a major health problem of children from rural areas of developing countries including Yemen. In an attempt to reduce this burden, the Ministry of Public Health and Population in Yemen established in 2002 a programme for Schistosomal, soil transmitted infection control that aimed to reduce morbidity and prevalence rates of Schistosomiasis, and Soil transmitted helminthes to less than 5% by 2015. The study was conducted to assess the current prevalence and intensity of schistosomal infection among schoolchildren in rural areas of the Taiz governorate after 6 years of running National Control Programme.

METHODS

Grade 3 schoolchildren from Shara'b Al-Raona district of Taiz Governorate were examined for infections with Schistosoma mansoni using Modified Kato-Katz method and S. haematobium applying filtration method in 1998/1999, comparing the prevalence and intensity of infection with base line study, which was done 6 years ago.

RESULTS

The S. mansoni prevalence in the study population was 31%, while the prevalence of S. haematobium was 18.6%. This result considerably is similar to the prevalence of base line study. The intensity of mild, moderate and severe infection for S. mansoni reached to 15.9%, 60.6% & 23.5% respectively. The severity of S. haematobium infection was 68.4%. It was exceptionally found that the prevalence of S. haematobium is increased.

CONCLUSION

The high prevalence of schistosomiasis and low effectiveness of control programme against schistosomal infection in the study area demands consideration of alternative treatment approaches.

Mechanisms of neural reorganization in chronic stroke subjects after virtual reality training

This study investigates patterns of brain reorganization in chronic stroke subjects after two weeks of robot-assisted arm and hand training in virtual reality (VR). Four subjects were studied with event-related fMRI while doing simple paretic hand finger movements before (double baseline) and after training. Bilateral hand movements were recorded and used to provide real-time feedback to subjects during scanning to eliminate performance confounds on fMRI results. The kinematic parameters of each movement were also used in the general linear model with the BOLD signal to investigate training-induced changes in neuromotor coupling. Univariate analysis showed an increase in BOLD signal in the ipsilesional hemisphere in two subjects and a decrease in activity in the other two subjects. Seed voxel based functional connectivity analysis revealed an increase in connectivity between ipsilesional motor cortex and bilateral sensorimotor cortex during finger movements in all four subjects. Hemispheric laterality index values showed a tendency to decrease reflecting a reduction in the over-dominance of the contralesional hemisphere. The study is novel in terms of 1) tracking finger movement during a motor task in the scanner, 2) monitoring motor performance during the experiment and 3) giving online visual feedback of subjects' movement. This pilot study introduces a novel approach to study neural plasticity by combining measures of regional intensity, interregional interactions (using functional connectivity analysis and hemispheric laterality index), and modulation in the strength of neuromotor coupling.

Failure to recognise the impact of 'moderate' obesity (BMI 30-40) on adverse obstetric outcomes

Obesity is a growing epidemic in the western world. We carried out a comparative analysis of the incidence of obstetric morbidity in three BMI categories in the ranges 30-40 to identify which BMI category was associated with greatest risk. This identification could help target limited maternity care resources to the group of women who would benefit most. There exists a scale continuum of risk of obstetric morbidity with maternal obesity: the greater the BMI, the greater the risk. However, pregnant women with mild or moderate obesity are still at significant risk of having pre-existing co-morbidities of developing antenatal complications and of being delivered by caesarean section than women with BMIs within the normal range. These women, at the time of antenatal booking, are currently not perceived by healthcare providers as having at-risk pregnancies and are therefore potentially denied access to best care.

Triclosan - an update

The discovery in 1998 that triclosan has a site-specific action in the bacterial cell as an inhibitor of NADH- or NADPH-dependent enoyl-acyl carrier protein reductase led to a lively debate in the scientific press. The thesis of this debate was that such a mode of action may allow triclosan to induce resistance and cross-resistance in bacterial cells. The debate last saw review in 2004, and this paper aims at updating our knowledge in this area, given recent research on the topic.

The effect of subminimal inhibitory concentrations of antibiotics on virulence factors expressed by Staphylococcus aureus biofilms

AIMS

The effect of subminimal inhibitory concentrations (sub-MICs) of cefalexin, ciprofloxacin and roxithromycin was investigated on some virulence factors [e.g. coagulase, Toxic Shock Syndrome Toxin 1 (TSST-1) and biofilm formation] expressed by Staphylococcus aureus biofilms.

METHODS AND RESULTS

Biofilms were grown with and without the presence of 1/16 MIC of antibiotics on Sorbarod filters. Eluate supernatants were collected, and coagulase and TSST-1 production were evaluated. Coagulase production was reduced in eluates exposed to roxithromycin when compared to control, while TSST-1 production was reduced in biofilms exposed to cefalexin and to a lesser extent, ciprofloxacin. In addition, the ability of Staph. aureus to produce biofilm in microtitre plates in the presence of sub-MIC antibiotics indicated that cefalexin induced biofilm formation at a wide range of sub-MICs. TSST-1 produced from the challenged and control biofilms was purified, and its proliferative activity was studied on single cell suspension of mouse splenocytes using MTS/PMS assay. No significant difference in the activity between the treated toxin and the control has been observed.

CONCLUSIONS

Antibiotics at sub-MIC levels interfere with bacterial biofilm virulence expression depending on the type and concentration of antibiotic used.

SIGNIFICANCE AND IMPACT OF THE STUDY

The establishment of sub-MICs of antibiotics in clinical situations may result in altered virulence states in pathogenic bacteria.

HLA class I and class II polymorphisms in Saudi patients with myasthenia gravis

Myasthenia gravis (MG) is a rare autoimmune disease of the neuromuscular junction. MG has been shown to be associated with many HLA antigens in different populations. Here we have analysed the frequency of HLA-A, B, DR and DQ in a group of Saudi MG patients and compared their results to a group of healthy controls. MG in Saudi patients is found to be associated with HLA-A*23, B*08, B*18, DRB1*16 and DRB1*13. The strongest association was with HLA-B*08, which was associated with young age at onset and female gender. Our results are in line with other published results from around the world and warrant fine mapping of the area using microsatellite to map the disease gene.

Pronase-free B-cell flow-cytometry crossmatch

Detection of anti-class II antibodies by panel response assay (PRA) and flow cross-match techniques carries an important value in terms of graft function. Even low levels of pre-formed alloantibodies to HLA class II antigens represent a risk of rejection. We present here a method for blocking non-specific flow crossmatch reactions using pooled, heat-inactivated rabbit serum. This method shows very low background and minimal non-specific reactions. In addition, it avoids the use pronase enzyme that can non-specifically digest different cell surface proteins.

Pharmacokinetic monitoring of intravenous cyclosporine A in pediatric stem-cell transplant recipients. The trough level is not enough

In order to monitor CsA serum levels after SCT, trough levels (C0) are widely used. The aim of this study was to estimate the population and individual PK parameters for patients receiving intravenous CsA after SCT. In 27 pediatric patients after SCT receiving CsA (3 mg/kg/day) every 12 h, a total of 289 CsA concentrations was obtained. To describe the PK parameters of CsA, a two-compartment model with first order elimination was used. Covariate analysis identified body weight, age, and the co-administration with itraconazole and tobramycine as factors influencing the Cl. The statistical comparison of AUC, trough level, and C2 indicates a correlation between AUC and C2, but no correlation between the AUC and C0, r = 0.24 (p = 0.146) vs. r = 0.526 (p = 0.000692), respectively. Our results underscore the fact that CsA trough levels do not reflect the drug exposure in patients receiving intravenous CsA after SCT. By contrast, CsA blood levels measured 2-6 h after CsA infusion showed a better correlation with the AUC. Our data provide new information to optimize the balancing act between GvHD-prophylaxis, graft vs. leukemia effect, and CsA side-effects after SCT.

255 DIURNAL RHYTHMS OF GLUCOSE AND NON-ESTERIFIED FATTY ACID CONCENTRATIONS IN BLOOD IN HEAT-STRESSED DAIRY CATTLE IN EGYPT

The hyperthermia associated with summer heat stress (HS) is a major cause of reduced fertility in high yielding dairy cows in the tropics and subtropics. The hyperthermia directly affects reproductive function. Furthermore, HS induces indirect effects (e.g. through a dropped dry matter intake and thus an altered energy balance), which may also have an impact on cow fertility. The extent of exposure to HS and HS-associated metabolic changes, such as hypoglycemia and high levels of non-esterified fatty acids (NEFA), may affect cattle fertility by impairing the developmental capacity of the oocyte. It is known that changes in glucose and NEFA concentrations in the blood may be reflected in the follicular fluid of the dominant follicle (Leroy et al. 2004). Therefore, the aim of the current study was to estimate to what extent oocytes may be exposed to HS-associated metabolic changes in dairy cattle during summer by assessing the diurnal changes in plasma. Respiration rate (RR) and rectal temperature (RT) along with plasma concentrations of glucose and NEFA were examined in 10 lactating Holstein cows at 4-h intervals from 7:00 AM to 3:00 AM for three successive days in August 2007. Temperature humidity indices (THI) were calculated as well. Linear mixed effect models with cow as random factor including the effect of daytime were used to investigate possible differences among studied parameters at different daytimes. At 3:00 PM, THI and RT were the highest (83.7 ± 0.6 and 40.1 ± 0.1, respectively) and the lowest value for THI recorded at 3:00 AM (74.2 ± 1.4) and for RT recorded at 7:00 AM (39.04 ± 0.08). RR increased gradually from 66.1 ± 3.1 resp min–1 at 3:00 AM to 93.0 ± 4 resp min–1 at 11:00 AM. Glucose concentrations decreased significantly (P < 0.001) at 11:00 AM and 3:00 PM. Decreased glucose concentrations coincided with increased NEFA concentrations at 11:00 AM and 3:00 PM (P < 0.001). The NEFA concentrations measured at 3:00 PM were significantly higher than at all other time points (Table 1). In conclusion, high producing dairy cows may be exposed to diurnal fluctuation of HS-associated metabolic changes such as significantly decreased glucose and increased NEFA concentrations in plasma for about 12 h per day, which may be reflected in the follicular fluid of the dominant follicle and as such directly affect oocyte and granulosa cell quality. Table 1.Mean ± SEM of glucose and non-esterified fatty acids (NEFA) concentrations (mmol L–1) in blood plasma of 10 lactating Holstein cows at 6 different daytimes during August 2007 in Egypt

Prevalence of Chlamydia trachomatis infection in infertile women at a university hospital in Jordan

In a prospective controlled study, we aimed to determine the prevalence of Chlamydia trachomatis infection in Jordanian women attending an infertility clinic and whether screening is useful as part of routine investigations for infertility. Two groups of patients (152 infertile patients and 146 control patients) had endocervical swab testing by polymerase chain reaction for the presence of C. trachomatis infection. A total of 6/152 patients in the infertility group tested positive for C. trachomatis (3.9%), compared with 1/146 patients in the control group (0.7%), a difference that was not statistically significant. In view of the tendency toward increased prevalence of C. trachomatis infection, screening women for chlamydial infection as part of routine investigations for infertility is recommended.

The value of frozen section Pipelle endometrial biopsy as an outpatient procedure in the diagnosis of ectopic pregnancy

This is a prospective study evaluating 28 patients who were suspected to have ectopic pregnancy. Frozen section Pipelle endometrial biopsy was performed as an outpatient procedure to look for the presence of chorionic villi in the specimen. The sensitivity of the frozen section endometrial biopsy in detecting the presence of chorionic villi was 13.3% and the specificity was 100%. The positive predictive value was 100% and the negative predictive value was 50%. We concluded that frozen section endometrial biopsy was not helpful in predicting intrauterine gestational process; therefore, it has a limited application in patients suspected to have ectopic pregnancy.

Human neutrophil gene expression profiling following xenogeneic encounter with porcine aortic endothelial cells: the occult role of neutrophils in xenograft rejection revealed

The role of innate immune cells in the recognition and activation of xenogeneic endothelium has always been considered secondary to the initial insult of xenoreactive natural antibodies (XNA) and complement. It was argued, however, that innate immune cells are capable of recognizing and activating xenogeneic endothelium in the absence XNA and complement. Here, we show that porcine aortic endothelial cells (PAECs) activate human neutrophils directly. This contact-dependent activation causes a transient calcium rise leading to increased reactive oxygen metabolite (ROM) production. Neutrophil gene-expression profiling using an adenylate uridylate-rich element-based microarray revealed a dramatic change in the neutrophil gene profiles upon exposure to PAECs. The PAEC-dependent neutrophil transcriptional activity was further confirmed by real-time polymerase chain reaction, which revealed a rapid increase in the mRNA message of a number of inflammatory cytokines. The activation of human neutrophils by PAECs was independent of galactose alpha1,3-galactose (Galalpha1,3-gal) structures, as inclusion of saturating concentrations of anti-Galalpha1,3-gal l antibodies had no significant effect. Furthermore, this activation was inhibited in the presence of the calcium chelator 1,2-bis(O-aminophenyl-ethane-ethane)-N,N,N',N'-tetraacetic acid-acetoxymethyl ester and the ROM inhibitor diphelylene iodonium. Our data illustrate the direct activation of innate immune cells by PAECs in the absence of XNA and complement and suggest alternative recognition sites between PAECs and human innate immune cells.

Reproductive outcome after abdominal myomectomy

This is a retrospective study to evaluate the reproductive outcome after abdominal myomectomy. Seventy myomectomies were performed at the Jordan University Hospital over a 10-year period. Fifty-five percent of these patients were infertile at the time of surgery. The most common indication for the myomectomy was a combination of infertility and menorrhagia (34.2%). A successful pregnancy was recorded in 53.8% of those who attempted pregnancy after the operation.

Immobilization of rolling NK cells on platelet-borne P-selectin under flow by proinflammatory stimuli, interleukin-12, and leukotriene B4

Recruitment of leukocytes from bloodstream to extrahematic sites is tightly regulated by a variety of adhesion molecules that are expressed on the leukocytes and the vessel walls. In this manuscript, we describe the interactions between natural killer (NK) cells and activated, autologous platelets under physiologic flow. We found that surface-adherent human platelets are capable of recruiting human NK cells from flow and that this recruitment is characterized by an initial tethering followed by a rolling phase. Both phases were dependent on the adhesion molecule P-selectin and its counter-ligand on the NK cells (P-selectin glycoprotein ligand 1). Activation of rolling NK cells with inflammatory mediators commonly found in atherosclerotic plaques (interleukin-12 and leukotriene B4) causes immediate cessation of the rolling process and conversion to stationary adhesion. Blocking antibodies to the adhesion molecules membrane-activated complex-1 and leukocyte function antigen-1 inhibited this conversion. Our data suggest that platelets deposited at sites of vascular injury may provide an alternative substrate to endothelial cells for initial recruitment of NK cells to the vessel wall. This may result in extravasation of the NK cells if the appropriate chemotactic signal is applied. These data implicate the P-selectin and integrin family of adhesion molecules in the recruitment of NK cells to atherosclerotic sites.

Gastroprotective activity of Nigella sativa oil and its constituent, thymoquinone, against gastric mucosal injury induced by ischaemia/reperfusion in rats

Ischaemia/reperfusion (I/R) induced gastric lesion, is known to be linked with free radical (FR) formation. Therefore, this model was used to assess the antioxidant effects of Nigella sativa oil (N.O) and thymoquinone (TQ) on gastric mucosal redox state and gastric lesions, 1 and 24 h after reperfusion. Male Wistar rats were subjected to I/R and were injected with either N.O (2.5 and 5 ml/kg, p.o) or TQ (5, 20, 50 and 100 mg/kg, p.o). The results showed that I/R elevated the levels of lipid peroxide (LPX) and lactate dehydrogenase (LDH), while decreased those of reduced glutathione (GSH) and superoxide dismutase (SOD). These biochemical changes were accompanied by an increase in the formation of gastric lesions, which was reduced by either treatment. N.O tended to normalize the level of LDH, GSH and SOD. However, its effect to restore LPX was only seen 24 h after reperfusion. Moreover, the aforementioned parameters were nearly reinstated by TQ. On the other hand, high doses of TQ (50 and 100 mg/kg) severely reduced the GSH content, 1 h after reperfusion. These results indicate that both N.O and TQ possess gastroprotective effect against gastric lesions which may be related to the conservation of the gastric mucosal redox state.

Structure of the malondialdehyde deoxyguanosine adduct M1G when placed opposite a two-base deletion in the (CpG)3 frameshift hotspot of the Salmonella typhimurium hisD3052 gene

Malondialdehyde (MDA) is a toxic and mutagenic metabolite produced by lipid peroxidation, and prostaglandin biosynthesis. MDA induces frameshift mutations in tester strains of Salmonella typhimurium. It reacts with DNA, and at physiological pH the major adduct is a pyrimidopurinone formed by reaction with guanine: M1G [3-(2'-deoxy-beta-D-erythropentofuranosyl)pyrimido[1,2-alpha]-purin-10(3H)-one]. When site-specifically incorporated into a duplex oligodeoxynucleotide containing a frameshift-prone (CG)3 repeat derived from the Salmonella typhimurium hisd3052 gene, spontaneous opening of M1G to the N2-(3-oxo-1-propenyl)-dG species occurred. In this work d(ATCGCMCGGCATG), (M=M1G) was annealed to d(CATGCCGCGAT) to model the putative strand slippage intermediate which would precede a two base deletion in the (CG)3 iterated repeat. 1H NMR studies indicate that in contrast to the duplex DNA structure, M1G remains intact. A single bulge conformation exists. M1G and its 3'-neighbor cytosine are unpaired. The M1G is intrahelical and stacked, whereas the unpaired cytosine is poorly stacked and appears to be extrahelical.

Cross-reactivities between date palm (Phoenix dactylifera L.) polypeptides and foods implicated in the oral allergy syndrome

BACKGROUND

Date fruit and pollen antigens share a number of cross-reactive epitopes. Date pollen has been shown to cross-react with antigens from Artemisia, cultivated rye (Secale cereale), Timothy grass (Phleum pratense), Sydney golden wattle (Acacia longifolia) and Bermuda grass (Cynodon dactylon) pollen. The present study was carried out to examine any cross-reactivities between date palm polypeptides and antigens of some common foods and vegetables that have been implicated in the oral allergy syndrome (OAS). Because most of such cross-reactivities in other allergens are attributable to the presence of carbohydrate chains and profilin, their role was also investigated.

METHODS

Fresh extracts of 20 common fruits and vegetables were prepared. Putative date profilins were isolated by affinity chromatography using a poly L-proline column. Date fruit extracts were digested by various endoglycosidases and the immunoglobulin (Ig)E binding of the postdigest products was assessed in immunoblots. Rabbit antisera to whole date fruit extracts, Timothy grass profilin and putative date profilins, as well as human sera from date sensitive individuals were used in immunoblotting, ELISA and in inhibition experiments.

RESULTS

IgG, ELISA and immunoblot results with the different rabbit antisera and date-sensitive atopic sera showed several antigenic cross-reactivities and similar cross-reactivities were seen with birch, date and timothy grass profilins. IgE, ELISA and immunoblot experiments with pooled date sensitive human sera showed a range of cross-reactivities with some food extracts. A number of the IgE cross-reactivities could be inhibited after preabsorption of pooled sera with date extracts. Sixty-six percent of individual date hypersensitive human sera bound IgE in putative date fruit profilin and their pooled sera bound IgE in birch pollen profilin. IgE-binding of the endoglycosidase digested date fruit extracts to atopic serum pool was restricted to only a very low molecular weight band of 6.5-8 kDa.

CONCLUSION

These results indicate that date palm polypeptides share cross-reactive IgG and IgE epitopes with a number of foods implicated in the oral allergy syndrome, bind to birch and Timothy grass profilins and bind IgE through glycosyl residues. The clinical relevance of these cross-reactivities needs to be further elucidated.