Pregnancy-induced periodontal inflammation: Influence of salivary cytokines and antimicrobial proteins

The aim of this study was to evaluate the association between pregnancy-induced periodontal inflammation and levels of some salivary cytokines and antimicrobial proteins (AMPs). The study was a cohort longitudinal study that included pregnant women attending a secondary health facility. Consented participants had oral examination and saliva sampling during pregnancy and post-partum (three months after pregnancy). Saliva samples were used for the analysis of cytokines (TNF-α, IFN-gamma and IL-1β) and AMPs (Lactoferin, Lysozyme, and β defensin-1) using ELISA. Data are presented as median with interquartile range and compared using related sample Wilcoxon signed rank test. Correlations between levels of the salivary factors and indices of periodontal inflammation were determined using Spearman’s correlation test. Salivary flow rate, pH, levels of salivary IL-1β and IFN-gamma were significantly lower; while gingival index, periodontal index and level of salivary TNF-α were significantly higher during pregnancy compared with postpartum period. However, salivary lactoferin, lysozyme and β defensin-1 did not show significant difference comparing during pregnancy and postpartum period. Level of salivary IFN-gamma showed negative correlation with gingival index while level of salivary TNF-α showed positive correlation with gingival and periodontal indices. Lower levels of salivary IL-1β and IFN-gamma along with higher TNF-α concentration during pregnancy suggest their contributions to the pathophysiology of pregnancy-induced periodontal inflammation.     

Suicide risk among adults with epilepsy in Kaduna,Nigeria

Objective

There is paucity of information on epilepsy and suicide in Nigeria. The objective of this study therefore was to assess the prevalence and determinants of suicide risk among adults with epilepsy (AWE) in Kaduna, Nigeria.

Method

We administered the suicidality module of the Mini International Neuropsychiatric Interview, the three-item Oslo Social Support Scale and the Hospital Anxiety and Depression Scale to 170 consecutive AWE attending the outpatient clinic of Federal Neuropsychiatric Hospital, Kaduna, between January and June 2011 to determine the prevalence of suicide risk, the level of social support and the psychological symptoms, respectively. We also recorded the sociodemographic and clinical characteristics of the subjects.

Results

There are 99 males and 71 females. The subject’s mean age was 28.7±12.1 years. The prevalence of suicide risk was 20.0%. Short seizure-free periods (χ²= 4.658, P= .031), previous suicide attempts (χ²= 12.216, P< .001), anxiety symptoms (χ²= 5.075, P= .024) and depressive symptoms (χ²= 5.093, P= .016) were significantly associated with suicidal tendencies. However, after a logistic regression analysis, none of the above variables predicted suicide risk.

Conclusion

Suicide risk is common among AWE. Poor seizure control, previous suicidal attempts and emotional distress are associated factors.     

ADAM-10 and -17 regulate endometriotic cell migration via concerted ligand and receptor shedding feedback on kinase signaling

A Disintegrin and Metalloproteinases (ADAMs) are the principal enzymes for shedding receptor tyrosine kinase (RTK) ectodomains and ligands from the cell surface. Multiple layers of activity regulation, feedback, and catalytic promiscuity impede our understanding of context-dependent ADAM “sheddase” function and our ability to predictably target that function in disease. This study uses combined measurement and computational modeling to examine how various growth factor environments influence sheddase activity and cell migration in the invasive disease of endometriosis. We find that ADAM-10 and -17 dynamically integrate numerous signaling pathways to direct cell motility. Data-driven modeling reveals that induced cell migration is a quantitative function of positive feedback through EGF ligand release and negative feedback through RTK shedding. Although sheddase inhibition prevents autocrine ligand shedding and resultant EGF receptor transactivation, it also leads to an accumulation of phosphorylated receptors (HER2, HER4, and MET) on the cell surface, which subsequently enhances Jnk/p38 signaling. Jnk/p38 inhibition reduces cell migration by blocking sheddase activity while additionally preventing the compensatory signaling from accumulated RTKs. In contrast, Mek inhibition reduces ADAM-10 and -17 activities but fails to inhibit compensatory signaling from accumulated RTKs, which actually enhances cell motility in some contexts. Thus, here we present a sheddase-based mechanism of rapidly acquired resistance to Mek inhibition through reduced RTK shedding that can be overcome with rationally directed combination inhibitor treatment. We investigate the clinical relevance of these findings using targeted proteomics of peritoneal fluid from endometriosis patients and find growth-factor–driven ADAM-10 activity and MET shedding are jointly dysregulated with disease.A Disintegrin and Metalloproteinases (ADAMs), especially ADAM-10 and -17, are the principal mediators of proteolytic ectodomain shedding on the cell surface (1). ADAMs and the closely related matrix metalloproteinases (MMPs) work together as “sheddases” to cleave hundreds of diverse transmembrane substrates including growth factor ligands, receptor tyrosine kinases (RTKs), adhesion molecules, and even proteases themselves from the cell surface. Unfortunately, little is known regarding how such a broad palette of proteolytic activity integrates to modulate behaviors such as cellular motility. Furthermore, extensive cross-talk and complexity among signaling networks, proteases, and their substrates make understanding sheddase regulation on a component-by-component basis challenging (2). Therapeutics have targeted sheddases and their substrates for the treatment of invasive diseases such as cancer, yet many of these inhibitors have failed in clinical trials (3). Therefore, a need exists for understanding how the balance of sheddase-mediated degradation integrates multiple layers of signaling networks to coordinately influence cell behavior in various disease contexts.Here we study how sheddase activity contributes to cell migration in the invasive disease of endometriosis, defined by the presence of endometrial-like tissue residing outside the uterus. Up to 10% of adult females and 40% of infertile women have the disease, which also exhibits comorbidity with several cancers (4, 5). Endometriosis currently has no cure: hormonal therapies merely manage the disease with significant side effects, and surgery provides only temporary relief for many, with recurrence rates as great as 40% within 5 y postoperation (6). Like cancer, endometriosis is associated with aberrant cell invasion into ectopic organ sites, and endometriotic tissues often exhibit dysregulated molecular pathways commonly perturbed in other invasive diseases. Mitogenic and inflammatory phospho-signaling [for example, phosphorylated extracellular-signal-related kinase 1/2 (p-Erk1/2), phosphorylated protein kinase B (p-Akt), and phosphorylated p38 mitogen-activated protein kinase (p-p38)], RTKs (including epidermal growth factor receptor, EGFR), and metalloproteinases have all been clinically associated with endometriosis (7, 8), and consequently represent attractive therapeutic strategies (9–11).Many challenges in developing targeted therapeutics stem from network-level complexities such as compensatory feedback, and recent work has demonstrated how critical such mechanisms are to achieving therapeutic success, especially in cancer (12, 13). Computational models of systems-level biochemical networks have shown promise as tools to understand how multiple enzymatic reactions integrate to impact overall biological behavior, often with the goal of aiding the design of personalized or combination therapies (14, 15). Considering its complex role in disease, sheddase regulation represents an ideal application of such network-level approaches. In this work, we apply the “cue–signal–response” (CSR) paradigm (14, 15) (Fig. 1A) to examine how disease-implicated growth-factor cues interact with experimentally monitored phospho-protein and protease networks (collectively referred to as signals), ultimately to influence cellular migration response. Computational modeling elucidates quantitative and predictive relationships among multiple layers of experimental data and offers testable hypotheses of context-dependent behavior and signaling feedback. We find ADAM-10 and -17 to be critical regulators of motility that are dynamically controlled through several signaling pathways, thereby affecting cell behavior through both positive feedback from EGF ligand release and negative feedback from Hepatocyte Growth Factor Receptor (HGFR; MET), Human Epidermal Growth Factor Receptor 2 (HER2), and HER4 RTK shedding. We find kinase inhibition generally reduces ADAM-10 and -17 activities, reduces subsequent RTK shedding, and consequently allows the accumulated RTKs to enhance downstream c-Jun N-terminal kinase (Jnk) and p38 signaling. Thus, here we demonstrate an ADAM-10 and -17–based mechanism of rapidly acquired resistance to kinase inhibition through reduced RTK shedding that can be overcome with combination therapy. Targeted proteomic analysis of clinical samples from endometriosis patients indeed confirms growth-factor–driven ADAM-10 activity and consequent MET shedding are dysregulated with disease. Overall, our results have wide implications for designing combination therapies and identifying context-dependent personalized therapeutic strategies for both kinase and protease inhibitors.Open in a separate windowFig. 1.CSR study design. (A) CSR overview: we stimulate endometriotic cells with a panel of growth factor cues; record multiple downstream signals comprising measurements of phospho-signaling, sheddase regulation, and sheddase substrate regulation; and use computational modeling to map these observations onto cell migration responses. (B) Overview of signals and responses included in the CSR dataset. All receptors shown were directly measured and/or stimulated. (C) Experimental timeline of CSR study. Dark colored lines denote measurement time points. At lower left, cell migration is depicted as single-cell tracks, where initial cell positions were centered for visualization.     

Age-related hearing loss, vitamin B12, and folate in the elderly

Objective

Determine the correlation between the hearing threshold and the serum levels of vitamin B12 (cobalamin) and folic acid among elderly subjects (> 60 years) with age-related hearing loss (ARHL).

Study Design

Cross-sectional.

Setting

Community.

Subjects and Methods

Subjects included elderly who were found apparently healthy following repeated examination by physicians. The pure tone average (PTA) for the speech and high frequencies, and the serum folate and cobalamin were determined and the correlation found.

Results

The mean ± SD values of serum folate among the subjects with normal PTA in the speech frequencies (0-30 dB) was 412.3 nmol/L ± 17.6 nmol/L, while among those with hearing loss (HL), it was 279.1 nmol/L ± 17.2 nmol/L (P = 0.01). In the high frequencies, the mean ± SD values among the subjects with normal PTA was 426.3 nmol/L ± 17.6 nmol/L, while among those with HL, it was 279.14 nmol/L ± 171.2 nmol/L. The serum cobalamin among the subjects with normal PTA within the speech frequencies was 49.7 pmol/L ± 9.4 pmol/L, while among those with speech-frequency HL, it was 42.6 pmol/L ± 10.2 pmol/L. However, for high frequencies, the mean ± SD values among the subjects with normal PTA was 47.4 pmol/L ± 7.3 pmol/L, while among those with HL, it was 41.3 pmol/L ± 9.2 pmol/L. Spearman's correlation revealed that low folate (correlation coefficient = −0.27, P = 0.01) and cyanocobalamin (correlation coefficient = −0.35, P = 0.02) were significantly associated with increasing hearing threshold in the high frequencies. After adjusting for age, serum folate (correlation coefficient = −0.01, P = 0.01) was significant, while vitamin B12 (correlation coefficient = −0.01, P = 0.74) was not.

Conclusion

Serum folate was significantly lower among elderly with ARHL. Trials on nutritional supplementation may substantiate the role of serum folate in ARHL.     

Pharmacodynamic and efficacy profile of TGN 255, a novel direct thrombin inhibitor, in canine cardiopulmonary bypass and simulated mitral valve repair

Heparin-induced thrombocytopenia can be a life-threatening sequel to conventional use of unfractionated heparin in cardiopulmonary bypass (CPB). This study evaluated the pharmacokinetic/pharmacodynamic (PK/PD) and efficacy profile of a novel direct thrombin inhibitor, TGN 255, during cardiac surgery in dogs. Point-of-care coagulation monitoring was also compared against the plasma concentrations of TRI 50c, the active metabolite of TGN 255. The study was conducted in three phases using 10 animals: phase 1 was a dose-ranging study in conscious animals (n = 6), phase 2 was a similar but terminal dose-ranging study in dogs undergoing CPB (n = 6), and phase 3 was with animals undergoing simulated mitral valve repair (terminal) using optimal TGN 255 dose regimens derived from phases I and II (n = 4). During the study, PD markers and drug plasma levels were determined. In addition, determinations of hematologic markers and blood loss were undertaken. Phase 1 studies showed that a high-dose regimen of a 5-mg/kg bolus and infusion of 20 mg/kg/h elevated PD markers in conscious animals, at which time there were no measured effects on platelet or red blood cell counts, and the mean plasma concentration of TRI 50C was 20.6 microg/mL. In the phase 2 CPB dose-ranging study, this dosing regimen significantly elevated all the PD markers and produced hemorrhagic and paradoxical thrombogenic effects. In the phase 3 surgical study, a lower TGN 255 dose regimen of a 2.5-mg/kg bolus plus 10 mg/kg/h produced anticoagulation, elevated PD markers, and produced minimal post-operative blood loss in the animals. Plasma levels of TRI 50C trended well with the conventional point-of-care coagulation monitoring. TGN 255 provided effective anticoagulation in a canine CPB procedure, enabling successful completion with minimal blood loss. These findings support further evaluation of TGN 255 as an anticoagulant for CPB.     

Acyl-enzymes as thrombolytic agents in a rabbit model of venous thrombosis

A derivative of human lys-plasmin in which the active site has been reversibly acylated (BRL 26920; p-anisoyl human lys-plasmin) has been examined as a fibrinolytic agent in a previously described rabbit model of venous thrombosis and shown to be significantly more active and less fibrinogenolytic than free plasmin. A p-anisoylated derivative of a streptokinase (SK)-activated plasmin preparation was significantly less fibrinogenolytic in vivo than the non-acylated enzyme. Acylation increased the fibrinolytic activity of preparations of SK-plasmin activator complexes. BRL 26921, the active site anisoylated derivative of the primary 2-chain SK-plasminogen complex was the most potent fibrinolytic agent studied. SK-Val442-plasminogen complexes, free or acylated, were biologically inactive in this model and confirm the essential nature of fibrin binding processes for effective thrombolysis in vivo.     

Comparison of the hypotensive effects of streptokinase-(human) plasmin activator complex and BRL 26921 (p-anisoylated streptokinase-plasminogen activator complex) in the dog after high dose, bolus administration

In view of current interest in the possibility of rapid, high-dose administration of thrombolytic agents by the intravenous route in patients with coronary thrombosis (AMI), a study of this technique was carried out in the dog. Streptokinase-(human) plasmin activator complex (SK-Pm) and BRL 26921 (p-anisoylated streptokinase-(human) plasminogen activator complex) were each given at equivalent doses (28,500 IU/kg and 800 micrograms/kg respectively) to groups of beagle dogs by rapid injection over 10 sec and their effects on blood pressure, plasmin formation and kallikrein production were compared over the next 3h. SK-Pm produced, within 1-3 min, a pronounced hypotensive effect that was kinetically related to a rapid and steep rise in systemic plasmin and kallikrein concentrations. BRL 26921 had no hypotensive effect, the rise in plasmin production was slower and the rate and extent of kallikrein formation was significantly less than in the SK-Pm group.     

The evaluation of plasmin and streptokinase activator complexes in a new rabbit model of venous thrombosis

A new quantitative model for the examination of potential thrombolytic agents is described. A thrombus was formed in the inferior vena cava of the rabbit, using 125 I-labelled fibrinogen mixed with a standard amount of thromboplastin. The thrombus was anchored securely by means of a woollen thread inserted longitudinally into the lumen of the vein. Thrombotic extension of the radioactive clot and rethrombosis during the experimental period (5 h) were prevented by the administration of intravenous heparin. In control animals, the thrombus remained stable and there was no rise in te radioactivity of the circulating blood during 5 h. In animals given thrombolytic agents, lysis could be followed continuously by measuring the rise in blood radioactivity. Total lysis was determined by counting the radio-label in the residual clot after treatment. The model has been used to study the thrombolytic activity of streptokinase-human plasminogen complexes, activator-free plasmins of human and porcine origin, and human plasmin produced by streptokinase (SK) activation of human plasminogen. The role of activator complexes in the thrombolytic activity of SK-activated plasmin is discussed.     

Retinoblastoma--a clinico-pathological study in Ilorin, Nigeria

Retinoblastoma is the commonest childhood primary malignant intraocular neoplasm that is often characterized by spontaneous regression. They display photoreceptor differentiation. This study provides the clinical presentations and histological profiles of retinoblastoma in Ilorin, Kwara-State, in the North Central geo-political zone of Nigeria. A retrospective study of clinically and histologically verified retinoblastoma at the University of Ilorin Teaching Hospital, Ilorin, Kwara-State, Nigeria from January 1989 to December 2000 was undertaken. The clinical and histological features were analyzed using the patient's case folder and surgical pathology records. There were 20 patients, 9 males and 11 females (M:F ratio 1: 1.2), age range from 5 (1/2) months to 6 years with 23 eyeball tumours histologically confirmed retinoblastoma during the study period. Proptosis with chemosis was the most common clinical presentation (84.6 %). Bilaterality was 15 % in this study. Enucleation and Exenteration combined with chemotherapy were offered to 15 (75 %) and 5 (25 %) patients respectively. A poorly differentiated type with extensive areas of tumour necrosis was the commonest histological pattern. Thirteen (65 %) of the patients died before completing the course of chemotherapy.