• Caspase 8 Activation in Colon Carcinoma Cells to Enhance Fasl-Induced Cytotoxicity by Tumor-Specific Cytotoxic T Lymphocytes

      Lovett, Ilene; Plotkin, Alexander; Land, Rachel; Coe, Genevieve; Gontee, Precious; Lee, Jacob; Department of Chemistry and Physics (2016-03)
      Cytotoxic T Lymphocytes (CTLs) are the major effectors of the host cancer immune surveillance. FasL-induced cytotoxicity is one of the two effector mechanisms that CTLs use to kill tumor cells. Fas is the physiological ligand of FasL and its expression and function is often deregulated in cancer cells. Ceramide is a sphingolipid metabolite that mediates Fas function. We aimed at testing the hypothesis that ceramide analogs are effective in modulating Fas function to sensitize colon carcinoma cells to FasL-induced apoptosis by tumor-specific CTLs. We show that Fas is expressed in human colon carcinoma cells. However, hu- man colon carcinoma cells are not sensitive to FasL-induced apoptosis. Based on structures of existing ceramide analogs and ceramidase inhibitors, we used rationale design and synthesized twenty ceramide analogs as putative Fas function modulators. Six of these twenty ceramide analogs, IG1, IG2, IG3, IG4, IG5 and IG6, exhibit potent activity in sensitization of human colon carcinoma cells to FasL-induced apoptosis. In the molecular mechanism level, we observed that all these six ceramide analogs dramatically increased FasL-induced activation of caspase 8, an essential initiator caspase of the Fas receptor-death-inducing signaling complex. Funding Source: Augusta University Research Institute
    • Cloning of Human Suv39h1 for Inhibition Studies

      Jahan, Asmat; Shaikh, Zahid; Department of Chemistry and Physics (2016-03)
      Cancer is one of the leading causes of death in the Western world and is characterized by abnormal cell growth. Despite the advancement in genetic engineering, there is not a significant amount of change in the rate of morbidity associated with the disease. For human colorectal cancers (CRC), early diagnosis and treatment is important for survival; if the cancer has metasta- sized to the liver, the survival rates are poor. Hence, improvements must be made to the existing therapies for metastatic human CRC. Applying knowledge of molecular mechanisms to modify and control the outgrowth of cells is the key to introducing new therapies. Fas is a receptor protein involved in apoptosis or, more commonly known as, “cell death.” Human carcinoma cells lower the expression of Fas on the cell surface. This lowering of expression levels of Fas is correlated with increased levels of histone H3 lysine 9 trimethylation (H3K9me). SUV39H1 is a histone lysine methyltransferase which catalyzes H3K9me. The goal of this study is to identify novel SUV39H1-specific inhibitors to decrease the level of methylation at the Fas promoter. Thus, to initiate our study, we have cloned the gene for human SUV39H1 into the expression vector pET-21c(+). Upon transforming the recombinant DNA into an expression strain of E. coli such as BL21, we will overexpress and purify SUV39H1 using affinity chromatography. Ultimately, the activity of SUV39H1 will be tested in the presence of various inhibitors.
    • Does Leptin Treatment Decrease Alpha-Adrenergic Receptor Expression in Mouse Renal And Mesenteric Arteries?

      Momtahan, Mina; Department of Biological Sciences (2016-03)
      Obesity often leads to hypertension. Previous work from my lab demonstrated that the adipocyte-derived hormone leptin reduces the ability of the aorta to contract in response to adrenergic stimulation, likely due to a decreased expression of the aorta alpha-adrenergic receptors. However, it is not known whether leptin decreases the expression of alpha-adrenergic receptors in such arteries like the mesenteric and renal arteries that play a key role in the control of blood pressure. To determine whether leptin decreases alpha-adrenergic receptor expression in renal and mesenteric arteries, I infused leptin (10ug/day) by implanting subcutaneous mini-pumps in five male C57bl/6 mice. Five mice did not receive leptin and served as controls. After seven days of treatment I euthanized nine mice as one mouse died. Renal and mesenteric arteries were taken from the mice and mRNa was extracted from the arteries. Reverse Transcription (RT) was completed in order to induce the transcription of mRNA into cDNA. After checking the concentration of cDNA, real-time PCR (qPCR) conducted on the arteries revealed high CT values for a1D-receptor concluding that leptin-mediated increases in sympathetic tone decreased a1D-receptor expression. This data is supportive of my hypothesis that leptin- decreases adrenergic receptor expression in renal and mesenteric arteries.
    • Dual-RNA Guided Editing of E. Coli’s EcDnaB Helicase Using the Crispr-Cas9 System

      Jones, Preston Dimitri; Department of Chemistry and Physics (2016-03)
      Precise manipulation of the genomic DNA is necessary for the characterization and identification of new genes and proteins. New technologies have enabled more facile and precise genomic engineering. Genome editing using the clustered regularly interspaced short palindromic repeats (CRISPR)- CRISPR associated protein method affords precise manipulation of the genome. This system relies on a precise RNA guide (crRNA) that guides the cas9 nuclease to a specific location on the genomic, where it creates a double strand break (DSB). We can take advantage of this adaptive immunological advance and reprogram crRNAs to target whatever gene we like and introduce precise mutations to the genome by offering a designer template to introduce the changes and help the cell remain viable. This method is on the forefront of biochemistry and is being implemented in a numerous eukaryotic systems. However, it has yet to be fully utilized in bacterial genome editing. We are interested in exploring the bacterial helicase EcDnaB. The EcDnaB helicase has been hypothesized to unwind DNA in two fashions; both strands simultaneously or by unwinding one strand while excluding the other. Our lab postulates that there is a steric exclusion of one of the strands as it winds around the exterior of the helicase via electrostatic interactions. We used the CRISPR-Cas9 system to precisely mutate six loci on the EcDnaB gene, corresponding to amino acid residues on the external surface of the helicase, in order to better understand the mechanism of unwinding and to support our proposed method of unwinding. Funding Source: National Science Foundation
    • The Effects of Increased Noise Levels on the Production of Corti-Costerone in Hyla Squirella

      Harris, Barbara; Department of Biological Sciences (2016-03)
      This research is focusing specifically on Hyla squirella and the effects of increasing traffic noise on CORT production. The specific aim of this research is to determine stress levels in H. squirella when exposed to varying roadside noise environments. We evaluated CORT levels in frogs exposed to varying noise levels in effort to correlate environmental noise to physiological stress. The corticosterone levels are measured through the waterborne technique. By placing the frog in 10 ml of water, the CORT was diffused out of the frog’s skin. The samples were ran through C-18 columns and then eluted with methanol. The samples are analyzed via a corticosterone enzyme-linked immunoassay kit. The experimental frogs were observed outside of the refugia more frequently and the coloration dulled over time. After 2 weeks, the experimental average corticosterone level were higher than the control cages. The average CORT decreased by the final CORT extraction. It appears that overall there is a stress related reaction when exposed to heavy noise. It appears that overtime the frogs will acclimate likely due to the fact that producing high stress for a long amount of time has physiological effects and may eventually lead to death. Funding Source: Augusta University Honors Program
    • Effects of Monoamine Uptake Inhibitors in an Assay of Pain Depressed Behavior in Male Mice

      Alexander, Khadijah; Rodriguez, Taylor; Sarfo, Amma; Department of Psychological Sciences (2016-03)
      Consequences of pain include stimulation of some behaviors (e.g. reflexive withdrawal from stimuli), and depression of others (e.g. exercise, and work). Pain depressed behaviors are among the primary diagnostic and treatment concerns for physicians, but preclinical research has often explored pain stimulated behaviors. This discrepancy between basic research and clinical application may be one obstacle to the development of new pain treatments. In the present study, we modeled pain-related depression of behavior by observing nesting behavior in male ICR mice. Nest building is an innate mouse behavior that is reduced when the mouse is exposed to a pain stimulus. Pain-related depression of nesting is blocked by the clinically effective nonsteroidal anti-inflammatory drug (NSAID) ketoprofen. This project examines effects of monoamine uptake inhibitors with varying selectivity for serotonin (5HT), norepinephrine (NE) and dopamine (DA) on pain-related depression of nesting. Citalopram (5HT-selective), nisoxetine (NE-selective), milnacipran (mixed action, 5HT/NE-selective), and bupropion (DA-selective) were evaluated for their ability to block pain-related depression of nesting. Results show that the monoamine uptake inhibitors lacking significant dopamine had no effect on pain-depressed nesting. This finding is consistent with previous work suggesting that dopamine may be a key neurochemical target in the treatment of pain-related depression of behavior. Funding Source: Department of Psychological Sciences
    • The Effects of Perfuorooctanoic Acid on Expression of Estrogen Receptor Alpha MRNA and Protein in Mcf-7 Cells

      Gillen, Laura; Peloquin, Rachel; Department of Biological Sciences (2016-03)
      Endocrine disruptors, such as Perfluorooctanoic acid (PFOA), are known to interfere with normal hormonal processes and could lead to detrimental effects on development and reproduction. PFOA is a ligand to peroxisome proliferator-activated receptors (PPARs), which have been demonstrated to crosstalk with estrogen receptors. Previous studies in our lab have demonstrated that treatment of MCF-7 breast cancer cells with 100μM PFOA significantly decreases cell viability. As both isoforms of the estrogen receptor (ER), alpha and beta, have been shown to regulate proliferation and apoptosis, this study aims to determine whether the decrease in viability is associated with changes in the expression of estrogen receptor. Cells were treated for 24h and 48h with vehicle (DMSO), 50μM and 100μM PFOA then harvested for either RNA or protein isolation. PCR analysis revealed minimal expression of ER beta in MCF-7 cells, consistent with the literature. ER alpha mRNA levels were significantly reduced by 24h in cells treated with both 50μM and 100μM PFOA. We are in the process of running western blots to determine whether or not there is a similar decrease in ER alpha protein levels in MCF-7 cells treated with PFOA. Funding Source: Center for Undergraduate Research and Scholarship and Department of Biological Sciences
    • The Effects of Relaxing and Energizing Piano Music on Anxiety when Academically Stressed

      Santiago, Ashley; Department of Psychological Sciences (2016-03)
      The purpose of this study is to determine whether the type of piano music played affects participants’ anxiety levels during a mildly stressful event in an academic setting. For this experiment, relaxing piano music is compared with energizing piano music to investigate which music type has the greatest effect on decreasing symptoms of state anxiety. These two conditions will be compared to a control group of no music. My hypotheses are: 1) Those in the music conditions will have lower anxiety scores at the end of the experiment than those in the control condition; 2) Those in the music conditions will have a smaller increase in pre-post state anxiety scores than those in the control condition, 3) There will an interaction between trait anxiety and music condition on state anxiety scores so that those who are high in trait anxiety and in the control condition will have the highest post-test state anxiety scores; and 4) There will be negative associations between the post-state anxiety scores and participants’ perceptions of how helpful the music was, and how frequently they listen to music when stressed. I do not expect significant differences between the two music conditions on any of the dependent measures.
    • Enhancing Radiation Sensitivity in Anaplastic Thyroid Cancer: Novel Therapeutic Strategies to Target a Killer

      Latremouille, Rachel; Department of Health Sciences (2016-03)
      Anaplastic thyroid carcinoma (ATC) is an aggressive cancer, with those diagnosed typically living only sixth months. This cancer normally effects the elderly, with an estimated 67% of patients being 70 years of age or older. One of the reasons ATC is such a deadly disease is the lack of effective treatment options. While chemotherapy and radiation are effective treatments for many cancers, they usually have little efficacy for ATC patients. However, our lab has discovered that cytokeratin-8 (CK8), a protein that plays a structural role in normal cells, has a novel and unanticipated role in promoting growth of ATC cells. Knock- down of CK8 in fast-growing ATC results in in a near-complete abrogation of cell growth, and an increase in apoptosis, in which the cell programs itself to die. Since ATC is normally resistant to radiation therapy, and one of the mechanisms of action for radiation in treating cancer is inducing DNA damage and subsequently apoptosis, we hypothesize there may be the potential for increased effectiveness between these two observations. To this end, we are investigating whether knocking down CK8 in ATC cell lines will increase radiation sensitivity, and will present the results at the conference.
    • Evaluating the Effects of Plant Oils on Feral Hog Behavior and Populations at Cowden Plantation, Jackson, SC.

      West, Valerie; Hunter, Austin; Minter, Bradford; Department of Biological Sciences (2016-03)
      Our research was conducted on Cowden Plantation, located along the Savannah River in Jackson, SC. In a previous study, it was hypothesized that feral hogs were being repelled by imitation catnip oil scent. This led to the question of whether that effect could be replicated and if other mint oils would have a similar effect. The primary purpose of this study was to observe the effects of a variety of mint oil extracts on the behaviors of the feral hog populations at ten locations on the Plantation. Feral hogs (Sus scrofa) were observed, via camera trapping, responding to the following oil extracts: Imitation Catnip Oil, Peppermint Oil, Eucalyptus Oil, Spearmint Oil, and Pure Catnip Oil. Cuddeback (IR and Black Flash) trail cameras were placed in open and forested habitats to monitor the species appearance and reaction using video clips. Scents were rotated every two weeks at each location, and all sites included two control weeks. A newly saturated scent tab was placed at each location in front of the cameras at the beginning of every week, and image cards were exchanged on those occasions. In summary, each camera went through a fourteen-week rotation with a different scent rotated every other week. Population densities were measured based on the number of images captured with scents compared to images captured without scents. Animal behavior was monitored through video and categorized into four different scent reaction groups: Smelled, Repelled, Rubbed Against, and Tasted. The most feral hog activity and behavioral responses occurred around the mint oils in both habitat areas. Most activity was captured when the ambient temperatures were warmer, and the oils were more aromatic. Funding Source: Center for Undergraduate Research and Scholarship and Department of Biological Sciences
    • Exploring the Function of Hob1 in the Non-Homologous End Joining Repair Pathway in Schizosaccharomyces Pombe

      Ozturk, Sarah; Department of Biological Sciences (2016-03)
      Mutations in DNA induce many diseases, including cancer. The human protein, Bin1, has anticancer properties and interacts with proteins involved in maintaining DNA stability and integrity. Work completed at the AU Cancer Center has shown that the Bin1 protein is specifically involved in the inhibition of the non-homologous end-joining pathway (NHEJ), a pathway that repairs DNA breaks. However, NHEJ is mutagenic because the DNA break is restored but some nucleotides are removed. To complement this work, we are investigating the role of Hob1, the homolog of Bin1, in fission yeast, in NHEJ. If Hob1 functions in a similar manner to Bin1, then removal of Hob1 from yeast should increase the cells’ ability to repair breaks in the DNA. We are testing this hypothesis using a genetic yeast transformation protocol that measures how efficient the yeast are at converting a linear piece of DNA into a repaired circular piece of DNA. Our data from two independent experiments show that removal of Hob1 has increased the rate of NHEJ. This result supports the hypothesis that Hob1 and Bin1 have a similar role in the repair process of DNA breaks.
    • Fish Assemblages in Brunsen Creek on St. Catherines Island, GA

      Sapp, Mikael; Ong, Claudia; McKittrick, Jacob; Moak, Jason; Department of Biological Sciences (2016-03)
      St. Catherines Island, in Liberty County, is one of Georgia’s uninhabited barrier islands. Due to its location approximately seven miles from the mainland and thirty miles from the Savannah River, the surrounding estuary has seen negligible anthropogenic impacts throughout its history. Specifically, Brunsen Creek, on its southern end, is considered to contain a pristine marine ecosystem. This study was initiated to provide baseline data for the surrounding Georgia estuarine ecosystems, many of which have had human impacts. Ichthyofaunal data was collected monthly within Brunsen Creek via trawling from September 2014 through August 2015, and will continue for the immediate future. Fishes collected show consistent relationships in natural migration and reproduction that have also been noted in other studies. Temporal trends in the appearance of fishes in Brunsen Creek samples, and their increasing lengths, reflect a well-established natural pattern along Georgia’s coast. Tracking these trends will provide a baseline of expected life history events for several species and a reference for further research within southeastern estuaries. Funding Source: Center for Undergraduate Research and Scholarship, Department of Biological Sciences and Museum of National History
    • HPA Activation: A Comparison between Shelter and Companion Dogs

      Alexander, Khadijah; McLarnon, Sean; White, Adam; Department of Biological Sciences (2016-03)
      Cortisol is considered to be a significant indicator of hypothalamic-pituitary-adrenal (HPA) axis activation in dogs. HPA activation is one of the most commonly used measures of stress in animal research. Saliva was used in this study as a noninvasive measure of cortisol. When dogs are entered into shelters they are exposed to many stressors that may influence their immune system and temperament, and can affect their prospects of adoption. Better understanding of stress-induced physiological changes in dogs bridges gaps in knowledge needed to improved welfare of these animals. Saliva swabs were used to collect saliva samples from 2 groups of dogs; county shelter dogs and companion dogs, to determine if there was a difference in cortisol levels between the two groups. The samples were analyzed using a cortisol immunoassay kit and a plate reader. We predict that there is a difference between the groups and that the salivary cortisol levels of the shelter dogs are higher than in the dogs kept as pets. Funding Source: Center for Undergraduate Research and Scholarship
    • Influence of Climate on Mosquito Abundance

      Haibach, Nicole; Department of Biological Sciences (2016-03)
      During this project one of the most common outdoors pest was observed, the mosquito. They are important to pay attention to due to their ability to transmit diseases and the irritation they are for humans. This project studied the effect of climate factors on mosquito abundance, which will help to predict when mosquitoes will be the most prevalent. Mosquitoes were collected using CDC gravid traps and light traps, which focused on different parts of the female mosquito life cycle. Mosquitoes were collected at 20 different locations in Richmond County, GA between February 2014 and December 2015. This study compared the impacts of different climate factors, such as precipitation amount, humidity, wind speed, and average temperature on the abundance and periodicity of two different species of mosquitoes, Culex quinquefasciatas and Culex salinarius. We found that temperature was positively correlated with the abundance of these species. Additionally, abundance of these species decreased significantly both above and below certain high and low temperature thresholds. This data will help to better predict when mosquitoes will be the most prevalent, which could help control the mosquito population better. Funding Source: Phinizy Center for Water Sciences
    • Integration of the Study of Molecular Evolution for Better Understanding of the Human Body

      Judy, Adam; Judy, Adam; Sanyal, Nilabhra M.; Sanyal, Nilabhra M.; Department of Biological Sciences; Department of Biological Sciences (2016-03201)
      Evolution by Natural Selection, proposed by Darwin and Wallace in the nineteenth century was mostly based on the paleontological evidences of animals and the study of the species. The rapid progress in molecular genetics and genomics from the mid-20th century helped us to better understand the molecular basis behind evolution and the link leading to the development of the advanced body mechanisms in humans. DNA is comprised of four bases across all the living species, within prokaryotes and eukaryotes as well as all other extinct species. But one small deviation at the molecular level in copying and translating the sequence can cause dramatic changes to a species over multiple generations, leading to speciation on a large scale. Humans differ by 1.2% genes with their closest ape ancestors, chimpanzees and bonobos. An advanced brain and higher level brain function was a major evolutionary advancement distinguishing Homo sapiens from its relatives. Evidence has also suggested that different illnesses, diseases, and other defects and benefits are linked to the differences in DNA among humans. Integration of the recent discoveries of how the gene sharing affects human bodies with traditional lecture will allow us to better understand the physiology thereby offering improved personalized health care. Funding Source: Department of Biological Sciences
    • Integration of the Study of Molecular Evolution for Better Understanding of the Human Body

      Judy, Adam; Sanyal, Nilabhra M. (2016-03)
      Evolution by Natural Selection, proposed by Darwin and Wallace in the nineteenth century was mostly based on the paleontological evidences of animals and the study of the species. The rapid progress in molecular genetics and genomics from the mid-20th century helped us to better understand the molecular basis behind evolution and the link leading to the development of the advanced body mechanisms in humans. DNA is comprised of four bases across all the living species, within prokaryotes and eukaryotes, as well as all other extinct species. But one small deviation at the molecular level in copying and translating the sequence can cause dramatic changes to a species over multiple generations, leading to speciation on a large scale. Humans differ from their closest ape ancestors, chimpanzees and bonobos, by 1.2% genes. An advanced brain and higher level brain function was a major evolutionary advancement distinguishing Homo sapiens from its relatives. Evidence has also suggested that different illnesses, diseases, defects and benefits are linked to the differences in DNA among humans. Integration of recent discoveries on how gene sharing affects human bodies with traditional lecture, will allow us to better understand the physiology, thereby offering improved personalized health care.
    • Investigating the Effects of DNA Damaging Agents on Survival in Hob1 Knockout Strains of Schizosaccharomyces Pombe

      Hashmi, Natasha; Department of Biological Sciences (2016-03)
      An important aspect of cancer research investigates why one tumor is resistant to chemotherapy while another tumor is sensitive to chemotherapy. The gene BIN1 when expressed renders chemoresistant cancer cells sensitive to DNA damaging agents in mammals. To better understand the extent of the chemosensitivity when BIN1 is expressed we are going to utilize the fission yeast, Schizosaccharomyces pombe. S. pombe has a functional homolog of BIN1 called HOB1 (Homolog Of Bin1). We have exposed both wild type and hob1Δ yeast strains to a wild variety of DNA damaging agents at various concentrations and accessed their survival rates. By comparing the sensitivities of wild type yeast to yeast lacking a function Hob1 protein we can have a better understanding of the role mammalian Bin1 protein plays in rendering cancer cells chemosensitive.
    • Investigating the Role of Hob1 in Translesion Synthesis in Schizosaccharomyces Pombe

      Walton, Breana R.; Department of Biological Sciences (2016-03)
      DNA replication is essential for an organism’s survival since the organism will die if the DNA is not replicated. The damage that DNA incurs may impede the progression of the replication process. The translesion synthesis (TLS) pathway bypasses damage, allowing replication to continue. Research conducted by our collaborator at the Augusta University Cancer Center indicates that the protein Rev1 physically interacts with Bin1, a protein involved in cancer progression in mammalian cells. We hypothesize that the two genes operate in the same pathway in yeast as they do in mammalian cells, and we intend to test this genetically. We conducted a mutation assay looking for an epistatic relationship between the two genes REV1 and HOB1, the homolog of Bin1 in Schizosaccharomyces pombe. These data suggest that Hob1 functions with Rev1 to allow for TLS, relieving stress caused by DNA damage during replication. Funding Source: Center for Undergraduate Research & Scholarship, Department of Biological Sciences
    • Led Type and Composite Photoinitiator Effects on Toothbrush Wear Resistance

      Chyan, David; Mettenberg, Donald; Department of Oral Rehabilitation (2016-03)
      Purpose: This research studied the effects of matching or mismatching dental light curing unit output color (blue or blue/vio- let, aka “multi-wave”) with the known photoinitiator content of dental restorative composites using toothbrush wear resistance. Methods: Combinations of lights and composites tested were a blue-only LED used to photocure a camphorquinone-only lay- ered composite, or a multi-wave LED used to activate composite containing Camphorquinone and Lucirin TPO photoinitiators. A ten-second exposure was provided to composite specimens utilizing all combinations of light curing units. Cured specimens were placed in a toothbrush-testing machine, simulating durations of 0, 4, 8, and 12 months of brushing. Surface profiles of composite surfaces were performed prior to as well as during tooth brushing. The average vertical loss of each specimen was measured within a 2.5-mm wide location. Regression analysis determined composite wear rates. Results: Using the blue-only LED on the Camphorquinone-containing composite resulted in a significantly lower wear rate than when using the multi-wave light on the same material. The opposite effect was found when using the blue-only LED on the Camphorquinone/TPO composite. SIGNIFICANCE: Optimal wear resistance of dental restorative composite surfaces is obtained by matching of LED spectral output with composite photoinitiator spectral needs. Funding Source: Frederick Rueggerberg
    • Macroinvertebrates and Water Quality in Oxbow Lakes along the Savannah River

      Wolff, Liam; Department of Biological Sciences (2016-03)
      Oxbow lakes are the remains of original channels that were cut off from the main river. Being more stagnant than the river, these lakes often differ in many physical, chemical, and biological parameters from the adjacent river. The goal was to compare four Savannah River oxbow lakes – Conyers, Miller, Possum Eddy, and Whirligig – to determine similarities and differences between oxbows with and without existing surface connections during non-flood flows. The comparison focused on water quality parameters and macroinvertebrate abundance and diversity. It is hypothesized that oxbow lakes with an existing surface water connection to the river have greater macroinvertebrate abundance and diversity than disconnected oxbows. Macroinvertebrates were sampled from sediment and other substrates using a petit ponar dredge and d-ring dip-nets, sorted according to EPA protocols, and identified to order or family. The resulting data showed that the most common organism at all sites were insects in the family Chironomidae, followed closely by members of the orders Cladocera, Anostraca, and Hemiptera. Among lakes, Conyer’s Lake (disconnected lake) was dominated by Bivalvia organisms, and Miller Lake (connected lake) was dominated by Hemiptera organisms whereas Chironomidae was the most common macroinvertebrate found in Possum Eddy (disconnected