The Akt inhibitor,triciribine, ameliorates chronic hypoxia-induced vascular pruning and TGFβ-induced pulmonary fibrosis

Background and Purpose

Interstitial lung disease accounts for a group of chronic and progressive disorders associated with severe pulmonary vascular remodelling, peripheral vascular rarefaction and fibrosis, thus limiting lung function. We have previously shown that Akt is necessary for myofibroblast differentiation, a critical event in organ fibrosis. However, the contributory role of the Akt-mTOR pathway in interstitial lung disease and the therapeutic benefits of targeting Akt and mTOR remain unclear.

Experimental Approach

We investigated the role of the Akt-mTOR pathway and its downstream molecular mechanisms in chronic hypoxia- and TGFβ-induced pulmonary vascular pruning and fibrosis in mice. We also determined the therapeutic benefits of the Akt inhibitor triciribine and the mTOR inhibitor rapamycin for the treatment of pulmonary fibrosis in mice.

Key Results

Akt1^−/− mice were protected from chronic hypoxia-induced peripheral vascular pruning. In contrast, hyperactivation of Akt1 induced focal fibrosis similar to TGFβ-induced fibrosis. Pharmacological inhibition of Akt, but not the Akt substrate mTOR, inhibited hypoxia- and TGFβ-induced pulmonary vascular rarefaction and fibrosis. Mechanistically, we found that Akt1 modulates pulmonary remodelling via regulation of thrombospondin1 (TSP1) expression. Hypoxic Akt1^−/− mice lungs expressed less TSP1. Moreover, TSP1^−/− mice were resistant to adMyrAkt1-induced pulmonary fibrosis.

Conclusions and Implications

Our study identified Akt1 as a novel target for the treatment of interstitial lung disease and provides preclinical data on the potential benefits of the Akt inhibitor triciribine for the treatment of interstitial lung disease.     

Clinical and functional outcomes in Middle Eastern patients with idiopathic pulmonary fibrosis

Background: Baseline clinical and physiological variables have been described as relevant predictors of survival among patients with idiopathic pulmonary fibrosis (IPF). However, substantial heterogeneity in both survival time and mortality has been observed with many of these predictive factors. The incidence and mortality rates of IPF vary from country to country, with race potentially contributing to such variations. Objective: We sought to describe baseline clinical features to determine their predictive value among Middle Eastern patients diagnosed with IPF. Methods: We retrospectively examined 61 patients diagnosed with IPF at a university hospital in Riyadh, Saudi Arabia. Results: At presentation, most patients exhibited either dyspnea or cough. The median survival time for all patients was 92 months. Diminished survival was significantly associated with finger clubbing (P = 0.01). Factors not influencing survival were age, gender, percent predicted forced vital capacity, percent predicted forced expiratory volume in 1 s, percent predicted total lung capacity, percent predicted diffusion capacity of the lung for carbon monoxide and resting oxygen saturation. Conclusions: Finger clubbing is a significant predictive variable and was associated with a 5‐fold increase in mortality. Other baseline demographic characteristics as well as pulmonary function tests were not predictive of prognosis in Middle Eastern patients with IPF. It appears that IPF patients of Middle Eastern descent have a longer median survival curve compared to other races. Please cite this paper as: Alhamad EH, Masood M, Shaik SA and Arafah M. Clinical and functional outcomes in Middle Eastern patients with idiopathic pulmonary fibrosis. The Clinical Respiratory Journal 2008; 2: 220–226.     

HLA class II DQA and DQB epitopes: Recognition of the likely binding sites of HLA-DQ alloantibodies eluted from recombinant HLA-DQ single antigen cell lines

Donor-specific antibodies (DSA) in sera of sensitized transplant patients are often produced against the specific epitopes on mismatched HLA antigens. In this study, we selected sera from 30 kidney transplant patients with DSA and AMR to define DQ epitopes. Using adsorption and elution assays, we identified 18 antibody reaction patterns to define 6 new epitopes and to confirm 12 previously defined epitopes. In one patient case, one mismatched antigen produced 3 different antibodies and, in another, antibodies were produced against the alpha and beta chains of the same antigen. For some sera, a single epitope can explain reactions for 27 of the 29 DQ beads in the single antigen panel.     

Neuroanatomical MRI study: reference values for the measurements of brainstem,cerebellar vermis,and peduncles

Objectives:To set age-specific normal reference values for brainstem, cerebellar vermis, and peduncles measurements and characterize values’ variations according to gender, age, and age by gender interaction.Methods:565 normal brain magnetic resonance examinations with normal anatomy and signal intensity of the supra- and infratentorial structures were categorized into six age groups (infant, child, adolescent, young adult, middle-age adult, and old aged adults). Patients with congenital malformations, gross pathology of the supra- or infratentorial brain, brain volume loss, developmental delay, metabolic disorders, and neuropsychological disorders (n = 2.839) were excluded. On midsagittal T₁ weighted and axial T₂ weighted images specific linear diameters and ratios of the brainstem, cerebellar vermis, and peduncles were attained. Two observers assessed a random sample of 100 subjects to evaluate the inter- and intraobserver reproducibility. Intraclass correlation coefficients, means ± standard deviation, one and two-way analysis of variance tests were used in the statistical analysis.Results:Good to excellent inter- and intraobserver measurements’ reproducibility were observed, except for the transverse diameter of the midbrain, the anteroposterior diameter of the medulla oblongata at the pontomedullary and cervicomedullary junctions, cerebellar vermis anteroposterior diameter, and thickness of the superior cerebellar peduncle. Age-specific mean values of the investigated measurements were established. A significant gender-related variation was recorded in the anteroposterior diameter of the basis pontis (p = 0.044), the anteroposterior diameter of the medulla oblongata at the cervicomedullary junction (p = 0.044), and cerebellar vermis height (p = 0.018). A significant age-related change was detected in all measurements except the tectal ratio. Age by gender interaction had a statistically significant effect on the tectal ratio, inferior, and middle cerebellar peduncles’ thickness (p = 0.001, 0.022, and 0.028, respectively).Conclusion:This study provides age-specific normal mean values for various linear dimensions and ratios of the posterior fossa structures with documentation of measurements’ variability according to gender, age, and their interaction.Advances in knowledge:It provides a valuable reference in the clinical practice for easier differentiation between physiological and pathological conditions of the posterior fossa structures especially various neurodegenerative diseases and congenital anomalies.     

Ameliorative effects of vitamin B17 on the kidney against Ehrlich ascites carcinoma induced renal toxicity in mice

Cancer is the major cause of death and many factors that lead to its occurrences, such as environmental pollution and pesticides and other factors. Ehrlich carcinoma development depends on many things associated with the environment, nutrition, personal habits, and family history. The present study aimed to evaluate the potential protective effects of vitamin B17 (VB17) against Ehrlich ascites carcinoma (EAC) that induced kidney toxicity in female mice. The mice were divided into five groups (first group, control group; second group, VB17 group; third group, EAC group; fourth group, pretreated EAC with VB17; fifth group, cotreated EAC with VB17). Results showed the VB17 in pretreated (G4) and cotreated (G5) groups lead to an improvement in DNA damage and cytological examination, in addition significantly (P < .05) increase in Na⁺, red blood cell, hemoglobin, hematocrit value, mean corpuscular hemoglobin (MCH), and MCH concentration, whereas significantly (P < .05) decrease in urea, creatinine, K⁺, platelets, and white blood cells while insignificant (P < .05) changes in mean corpuscular volume when compared to the EAC group. Many histopathological changes were observed in kidney sections in EAC as marked damage and degenerated, glomerular atrophy, the Malpighian corpuscles that lost their characteristic configuration. On the other hand, a moderate improvement and arrangement in the kidney histological structure in pretreated VB17 + EAC, while a mild enhancement and arrangement of the kidney structure in cotreated EAC + VB17. In addition, depletion in renal P53 and PCNA protein expression compared with the EAC group. It could be concluded that VB17 has a potential renal protective effect against EAC cells induced kidney injury.     

Optimization and evaluation of venlafaxine hydrochloride fast dissolving oral films

Three factors, three levels (3³) full factorial design was used to develop venlafaxine HCl fast dissolving oral films (FDOFs) to optimize the concentrations of the film forming polymer; hydroxypropyl methylcellulose HPMC (X1), superdisintegrant; sodium starch glycolate SSG, (X2) and glycerol as the film plasticizer (X3). Effects of the three factors on the disintegration time (Y1), swelling index (Y2), and dissolution efficiency at 15 min; DE%15 (Y3) of the prepared FDOFs were evaluated by using statistical models. The optimized film formula was characterized in term of x-ray powder diffraction (XRPD), differential scanning calorimetry (DSC) and morphological characteristics.Disintegration time was found to increase with the increase in HPMC (X1) concentration, and the shortest disintegration time (21.67 ± 2.08 s) was observed in case of F2 formula (lowest HPMC level and highest glycerol level in absence of SSG). The highest swelling index (3.64 ± 0.59) was observed in case of film formula F1 (medium concentrations of both HPMC and glycerol and highest SSG concentration. The results also indicated that as the concentration of HPMC increased the DE%15 decreased. SSG (X2), with highest value (72.33 ± 1.71%) was recorded for in case of F12 (using 2% HPMC, 5%SSG and 1.5% glycerol). The optimized FDOF formula derived by the statistical models suggested 2% HPMC, 5% SSG, and 1% glycerol.The data obtained from DSC and XRPD revealed no interaction between drug and FDOT excipients. In addition, XRPD studies proved that the venlafaxine HCl was homogeneously dispersed in the film matrix.     

Academic advising and student support: Help-seeking behaviors among Saudi dental undergraduate students

Objective

The purpose of this study was to assess the use of and satisfaction with the academic-advising and student-support systems available to undergraduate students in the College of Dentistry at the University of Dammam. In addition, the study aimed to also identify factors that explained the help-seeking behavior of students which they used to solve academic issues.

Materials and methods

Students enrolled in the five-year Bachelor of Dental Surgery (BDS) program in 2012–13 and 2013–14 first-year students were invited to respond to a self-administered questionnaire.

Results

The results showed that 66.2% of students had discussed academic issues with their advisor at least once, with a frequency ranging from zero to six times. Most students reported that their advisors were readily available, listened intently to their needs and questions, and helped them solve their problems. However, only 7.6% of students relied primarily on advisors for help with academic issues, whereas 51% depended first on colleagues and 13.8% did not seek help and relied on themselves. In total, 17.2% of students were very or somewhat satisfied with the academic advising system. Males had lower odds of discussing issues with their advisors, and the odds were higher with advisors who were more available (OR = 0.25 and 3.74, respectively). Alerting students to important dates in the academic calendar significantly increased the odds that a student would depend primarily on academic advisors for advice related to academic issues (OR = 6.53).

Conclusions

Few students were satisfied with the academic support system. We need to train advisors to help them develop their skills and knowledge and to enable them to provide the support needed by the students.