Investigating the role of enhancer-mediated gene expression in the human brain and its potential contribution to psychiatric disorders

Autism spectrum disorder (ASD) and schizophrenia (SCZ) are two neuropsychiatric conditions with variable times of onset and are influenced by both genetic and environmental factors. Genome-wide association studies (GWASs) have led to the identification of numerous genetic loci common to both these disorders, however our understanding remains far from complete, with many clinical cases without a genetic cause. While increasing the statistical power of genome-wide association studies (GWASs) to find additional risk variants could rule-in or rule out rare cases of ASD and SCZ, this presently remains a difficult task. Furthermore, the biological functions for genetic susceptibility loci remains poorly understood, particularly for more-recent discoveries of loci devoid of gene bodies. On the other hand, recent biotechnological developments have made it possible to conduct high-resolution experimental measurements of the three-dimensional architecture of the genome, including enhancer-promoter interactions (EPIs). Such data have been used to connect GWAS risk variants to their potential target genes which, in turn, provide insights into underlying molecular mechanisms and cellular processes. The functions of enhancer-promoter interactions in controlling gene expression programmes is crucial to how implicated genes mediate neurological function and disease. Yet, knowledge on enhancer-promoter interactions remains to be used in conjunction with GWAS data, particularly on such data from specific brain cell types, which may be useful to uncover the biological underpinnings of psychiatric conditions. This thesis examines the role of enhancer-mediated gene expression in the human brain and its potential contribution to psychiatric conditions. In Chapter 2, I report on the identification of significant chromosomal interactions from studies of brain Hi-C data generated from neuronal and glial cells, with the goal to investigate the impact of EPIs genome-wide, as well as to provide a template for an in-depth understanding of how EPIs impact transcriptional regulation. In the Chapter 3, I discuss a novel approach integrating Activity by Contact (ABC) and gene set enrichment analyses of GWAS data in two steps. In the first step, ABC is used to predict enhancer-gene regulatory interactions in a given cell type (e.g., glial cells, neurons). Secondly, Hi-C coupled multi-marker analysis of genomic annotation (H-MAGMA) is used to assign the SNPs located in the regulatory regions identified by ABC to each gene and calculate gene-level association p-values. I applied this novel framework (ABC-HMAGMA) to GWAS data from SCZ and ASD, to identify novel SCZ and ASD trait-associated genes and molecular pathways. In Chapter 4, I have evaluated a potential novel mechanism for the regulation of enhancer activity within cells. I hypothesized that, in addition to its known roles in DNA replication and transcription, Topoisomerase I may regulate enhancer activity in brain cells. To test this hypothesis, I employed RNA-seq and transient transcriptome sequencing (TT-seq) data, a method that enriches for short-lived enhancer derived RNAs. These data showed that Topoisomerase I inhibition leads to significant changes in eRNA expression and offers evidence that such changes are relevant to the homeostatic functions for Top 1 in cellular gene expression regulation

Surgical management of bilateral prolapse of the third eyelid glands in a Norwich terrier

An 8-month old Norwich terrier breed of dog that presented with bilateral prolapse of the third eyelid glands was treated surgically using the modified Morgan’s pocket technique in combination with the tacking of the third eyelids to the periorbital periosteum. The physiologic, haematological and biochemical parameters taken prior to treatment were all within the normal values. The combined surgical approaches adopted for the treatment were clearly described as well as the post operative management. The patient had a rapid positive response without recurrence even after 4 months, unlike what is always seen when the modified Morgan’s pocket technique is used alone.Keywords: Third eyelid glands, Prolapse, Surgical management, Norwich terrier do

Istraživanje analgetičnoga i sustavnoga učinka ibuprofena u kunića.

Ibuprofen suspensions (15 and 30 mg/kg b.m.) were orally administered to two groups of rabbits every 12 hours for three days following laparotomy. The effect of these doses on the pain scores, haematology parameters, several serum enzyme levels and gastrointestinal tract were evaluated. The results were then compared with the untreated group but laparotomised. The administration of 30 mg/kg b.m. ibuprofen produced a significantly (P0.05) different. Administration of the two doses of ibuprofen did not significantly (P>0.05) alter the packed cell volume (PCV), red blood cell count (RBC) and haemoglobin concentrations (Hbc) of the rabbits. Serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) significantly (P0,05). Primjena dviju doza ibuprofena nije značajno promijenila ukupan broj krvnih stanica, broj crvenih krvnih stanica i koncentraciju hemoglobina. Razine alanin-aminotransferaze (ALT) i aspartat-aminotransferaze (AST) u serumu značajno su bile povećane (P<0,05) u skupinama koje su dobivale ibuprofen. Značajan porast razine serumskoga kreatinina (P<0,05) zabilježen je u životinja kojima je dano 30 mg/kg ibuprofena. Ni u kontrolnih ni u pokusnih životinja nisu zabilježeni melena, povraćanje ni proljev. Zaključno se može reći da su dvije doze ibuprofena dovoljne da se smanji bol uzrokovana laparotomijom. Preporučuje se doza ibuprofena od 15 mg/kg tjelesne mase jer su se pri tom javljale slabije nuspojave od strane bubrega

A comparative study on ABO blood group and fertility hormones in infertile women in Calabar, Southern Nigeria

Infertility, a disorder of the reproductive system, is commonly linked to hormonal, pituitary, cervical, uterine, immunological or psychological factors. Besides these factors, it can also be idiopathic or unexplained. Hence, there is a need for more research to unravel the causes of the unexplained infertility. This work aimed at finding out whether there is any relationship between ABO blood group system and female infertility. The study design was cross-sectional. Three hundred women between 18 and 40 years attending fertility clinic at the University of Calabar Teaching Hospital, Calabar between 2011 and 2012 were recruited for this study. Serum progesterone, prolactin, follicle stimulating hormone (FSH), luteinizing hormone (LH) and estradiol were determined using Enzyme linked immunosorbent assay (ELISA) while ABO blood grouping was determined using the tube method. Statistical analysis was done using SPSS version 18. The confidence level was set at 95% where p-value less than 0.05 was considered statistically significant. The mean age of the women was 30.65 ± 5.47 years and the percentage distributions of the blood groups among the women were as follows: 24% A, 12% B, 4% AB and 60% O. The mean FSH levels of blood groups A and O individuals were significantly higher (p&lt;0.05) than that of groups B. However, there was no significant difference (p&gt;0.05) in the mean levels of progesterone, prolactin, LH and estradiol in the respective groups. From this study, 38% of the population had increased levels of progesterone, 58% and 18.7% had elevated prolactin and FSH levels respectively while 11.33% and 43.3% had reduced levels of LH and estradiol levels respectively. Though, there was high prevalence of hyperprolactinemia observed in this study, there was no strong association between ABO blood group and female infertility but, the increased FSH levels observed in blood groups A and O may be a potential link between blood group and infertility and therefore may be beneficial for further study

Istraživanje analgetičnoga i sustavnoga učinka ibuprofena u kunića.

Ibuprofen suspensions (15 and 30 mg/kg b.m.) were orally administered to two groups of rabbits every 12 hours for three days following laparotomy. The effect of these doses on the pain scores, haematology parameters, several serum enzyme levels and gastrointestinal tract were evaluated. The results were then compared with the untreated group but laparotomised. The administration of 30 mg/kg b.m. ibuprofen produced a significantly (P0.05) different. Administration of the two doses of ibuprofen did not significantly (P>0.05) alter the packed cell volume (PCV), red blood cell count (RBC) and haemoglobin concentrations (Hbc) of the rabbits. Serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) significantly (P0,05). Primjena dviju doza ibuprofena nije značajno promijenila ukupan broj krvnih stanica, broj crvenih krvnih stanica i koncentraciju hemoglobina. Razine alanin-aminotransferaze (ALT) i aspartat-aminotransferaze (AST) u serumu značajno su bile povećane (P<0,05) u skupinama koje su dobivale ibuprofen. Značajan porast razine serumskoga kreatinina (P<0,05) zabilježen je u životinja kojima je dano 30 mg/kg ibuprofena. Ni u kontrolnih ni u pokusnih životinja nisu zabilježeni melena, povraćanje ni proljev. Zaključno se može reći da su dvije doze ibuprofena dovoljne da se smanji bol uzrokovana laparotomijom. Preporučuje se doza ibuprofena od 15 mg/kg tjelesne mase jer su se pri tom javljale slabije nuspojave od strane bubrega

Renal histoarchitectural changes in nevirapine therapy: possible role of kolaviron and vitamin C in an experimental animal model

Background: There is paucity of literature regarding the nephrotoxicity of antiretroviral drugs and its interaction with plantbased adjuvants. This study investigates the attenuating effect of kolaviron in nevirapine- therapy on the histological structure of the kidneys of adult male Sprague-Dawley rats.Objective: To determine the attenuating influence of anti-oxidant status of kolaviron on the kidneys of experimental animals following nevirapine administration.Methods: Forty eight pathogen-free adult male Sprague-Dawley rats were used for this study. The animals were divided into 8 groups (A-H) with 6 animals in each group. Group A was given normal saline as the control; group B was given nevirapine; group C was given kolaviron; group D was given vitamin C; group E was given nevirapine and kolaviron; group F was given nevirapine and vitamin C; Group G was given nevirapine and kolaviron (kolaviron withdrawn after day 28) and group H was given corn oil. The experiment lasted 56 days after which the animals were sacrificed, blood samples were collected through cardiac puncture for serum analysis and the kidneys were harvested and prepared for H&amp; E histological examination.Results: Nevirapine caused histoarchitectural damage in the glomerular apparatus with resultant increase in kidney/body weight ratio (p&lt;0.001). Adjuvant treatment with kolaviron attenuated these nephrotoxic effects. Serum anti-oxidant enzyme (SOD and CAT) activities were significantly reduced in kolaviron and vitamin C treated animals, whereas in the nevirapine group these parameters were significantly elevated (P&lt;0.05). However, co-administration of nevirapine and vitamin C did not improve the histoarchitecture of the kidney.Conclusion: Adjuvant treatment with kolaviron (an anti-oxidant) for 56 days appears to attenuate the nephrotoxicity of nevirapine in this model.Keywords: Kidney, histoarchitecture, kolaviron, antiretroviral drug

Chronic Exposure to Toluene and Heavy Metals and Changes in Indices of Liver Function, Inflammation and Oxidative DNA Damage among Automobile Workers

Background: Oxidative stress (OS), oxidative DNA damage and inflammatory response induced by chronic exposure to volatile organic compounds and heavy metals (HM) have been implicated in multiple organ dysfunction. The liver enzymes (alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT)), biomarkers of OS (nitric oxide (NO), glutathione (GSH), total antioxidant capacity (TAC), total plasma peroxides (TPP), malondialdehyde (MDA)) oxidative stress index (OSI)), oxidative DNA damage (8-hydroxy-2-deoxyguanosine (8-OHdG)), and inflammation marker (tumor necrosis factor alpha (TNF-α)); heavy metals (cadmium (Cd), lead (Pb)) and urine hippuric acid (uHA) levels were assessed in automobile workers. Methods: Fifty automobile workers and 50 controls aged 18-60 years were enrolled into this study. The MDA, GSH, NO, TAC, TPP, ALT, ALP and GGT were estimated by colorimetry, 8-OHdG and TNF-α by enzyme linked immunosorbent assay, Cd, Pb by atomic absorption spectrophotometry and uHA by high performance liquid chromatography. Data were analyzed using t-test and correlation analysis at p <0.05. Results: Automobile workers had significantly higher liver enzymes, lipid peroxidation, oxidative stress, oxidative DNA damage, nitric oxide, HM, uHA and lower total antioxidants relative to controls. Heavy metals were positively associated with MDA, TPP and OSI; TPP with duration of exposure; ALP with number of working hours; and liver enzymes with OSI only in automobile workers. Conclusion: Association of exposure to toluene and heavy metals with increased liver enzymes activity, lipid peroxidation, oxidative stress, oxidative DNA damage, and depressed antioxidants in automobile workers suggest increased risk of hepatotoxicity and hepatocellular carcinogenesis

Renal histoarchitectural changes in nevirapine therapy: possible role of kolaviron and vitamin C in an experimental animal model.

Background: There is paucity of literature regarding the nephrotoxicity of antiretroviral drugs and its interaction with plant-based adjuvants. This study investigates the attenuating effect of kolaviron in nevirapine- therapy on the histological structure of the kidneys of adult male Sprague-Dawley rats. Objective: To determine the attenuating influence of anti-oxidant status of kolaviron on the kidneys of experimental animals following nevirapine administration. Methods: Forty eight pathogen-free adult male Sprague-Dawley rats were used for this study. The animals were divided into 8 groups (A-H) with 6 animals in each group. Group A was given normal saline as the control; group B was given nevirapine; group C was given kolaviron; group D was given vitamin C; group E was given nevirapine and kolaviron; group F was given nevirapine and vitamin C; Group G was given nevirapine and kolaviron (kolaviron withdrawn after day 28) and group H was given corn oil. The experiment lasted 56 days after which the animals were sacrificed, blood samples were collected through cardiac puncture for serum analysis and the kidneys were harvested and prepared for H&amp; E histological examination. Results: Nevirapine caused histoarchitectural damage in the glomerular apparatus with resultant increase in kidney/body weight ratio (p&lt;0.001). Adjuvant treatment with kolaviron attenuated these nephrotoxic effects. Serum anti-oxidant enzyme (SOD and CAT) activities were significantly reduced in kolaviron and vitamin C treated animals, whereas in the nevirapine group these parameters were significantly elevated (P&lt;0.05). However, co-administration of nevirapine and vitamin C did not improve the histoarchitecture of the kidney. Conclusion: Adjuvant treatment with kolaviron (an anti-oxidant) for 56 days appears to attenuate the nephrotoxicity of nevirapine in this model

Heavy metals, biomarkers of oxidative stress and changes in sperm function: A case-control study

Background: Heavy metal-induced oxidative stress has been implicated in abnormal sperm functions and male infertility. Objective: Serum and seminal levels of heavy metals and biomarkers of oxidative stress were compared in fertile and infertile men. Materials and Methods: A total of 130 men aged 20–60 yr comprising 30 azoospermic, 50 oligozoospermic, and 50 normozoospermic men were studied. Semen analysis was done by world health organization guidelines, biomarkers of oxidative stress (total antioxidant capacity (TAC), total plasma peroxidase (TPP), oxidative stress index (OSI), vitamin C (vit C) and nitric oxide (NO)) and fructose by colorimetry and serum and seminal heavy metals (zinc (Zn), selenium (Se), cadmium (Cd) and lead (Pb)) by atomic absorption spectrophotometry. Results: Azoospermic and oligozoospermic men had higher serum and seminal peroxides (TPP, p = 0.00), higher serum heavy metals (Zn, Se, Pb, and Cd (p = 0.01)) and lower sperm concentration, %motility, serum and seminal antioxidants (vit C, TAC, NO, GSH (p = 0.01)) compared to normozoospermic men. Higher seminal peroxides (TPP, p = 0.001), heavy metals (Pb and Cd (p = 0.03)) and lower sperm concentration, %motility, and seminal antioxidants (TAC and NO (p = 0.00)) were also observed in azoospermic men compared to oligozoospermic men. Negative correlations were observed between seminal fructose and seminal vit C (r = -0.535, p = 0.015), GSH (r =-0.734, p = 0.000), NO (r = -0.714, p = 0.000), Zn (r = -0.774, p = 0.000) and Se (r = -0.719, p = 0.000) only in azoospermic men. Conclusion: Elevated heavy metal levels, increased lipid peroxidation and antioxidant depletion is associated with abnormal sperm functions in men studied. Key words: Heavy metals, Antioxidants, Lipid peroxidation, Oxidative stress, Sperm function

Cement Dust Exposure and Perturbations in Some Elements and Lung and Liver Functions of Cement Factory Workers

Background. Cement dust inhalation is associated with deleterious health effects. The impact of cement dust exposure on the peak expiratory flow rate (PEFR), liver function, and some serum elements in workers and residents near cement factory were assessed. Methods. Two hundred and ten subjects (50 workers, 60 residents, and 100 controls) aged 18–60 years were studied. PEFR, liver function {aspartate and alanine transaminases (AST and ALT) and total and conjugated bilirubin (TB and CB)}, and serum elements {lead (Pb), copper (Cu), manganese (Mn), iron (Fe), cadmium (Cd), selenium (Se), chromium (Cr), zinc (Zn), and arsenic (As)} were determined using peak flow meter, colorimetry, and atomic absorption spectrometry, respectively. Data were analysed using ANOVA and correlation at p=0.05. Results. The ALT, TB, CB, Pb, As, Cd, Cr, Se, Mn, and Cu were significantly higher and PEFR, Fe, and Zn lower in workers and residents compared to controls (p<0.05). Higher levels of ALT, AST, and Fe and lower levels of Pb, Cd, Cr, Se, Mn, and Cu were seen in cement workers compared to residents (p<0.05). Negative correlation was observed between duration of exposure and PEFR (r=-0.416, p=0.016) in cement workers. Conclusions. Cement dust inhalation may be associated with alterations in serum elements levels and lung and liver functions while long term exposure lowers peak expiratory flow rate