I am a full professor at King's College, a small liberal arts college in Wilkes-Barre, Pennsylvania. I teach several courses including foundational Biology courses, Genetics, Physiology, Parasitology, and Bioinformatics. My forte is creating new laboratory exercises. I have an undergraduate research program that addresses wide topics from the Genetics of Dyslexia, the Effects of Wastewater Drugs on Amphibian Physiology, the Rat Tapeworm System, and the Genetics and Chemical Defense of Tribolium Beetles.
Tribolium beetles provide an excellent and easily manipulated model system for the study of genet... more Tribolium beetles provide an excellent and easily manipulated model system for the study of genetics. However, despite significant increases in the availability of molecular markers for the study of genetics in recent years, a significant genetic linkage map for these beetles remains undeveloped. We present the first molecular genetic linkage map for Tribolium confusum using random amplified polymorphic DNA markers. The linkage map contains 137 loci mapped on to eight linkage groups totaling 968.5 cM.
The interaction of the rat tapeworm,Hymenolepis diminuta, with its intermediate beetle host,Tribo... more The interaction of the rat tapeworm,Hymenolepis diminuta, with its intermediate beetle host,Tribolium confusum, is a well-studied model system. However, there is so much variation in the methods and designs of the studies that it is difficult to draw comparisons. This study simultaneously compared several aspects of the infection protocol including beetle age, sex, density and mating status; parasite egg condition, infection environment humidity and the times for the three steps of infection: starvation, feeding and post-feeding development. Although statistically limited by low prevalence and intensity levels, we were able to detect the relative effects of the variables. The effects of these variables on prevalence (percent infection) and intensity (mean number of cysticercoids) do not necessarily correlate with each other. Egg condition, reduced starvation times, higher beetle density and longer development times reduced prevalence. However, differences in intensity were only detected with older beetles. When coupled with survivorship data, our study found that our current infection protocol is optimal for infection success. However, the results suggest extending the study to other intermediate hosts and the inclusion of additional variables.
The interaction of the rat tapeworm,Hymenolepis diminuta, with its intermediate beetle host,Tribo... more The interaction of the rat tapeworm,Hymenolepis diminuta, with its intermediate beetle host,Tribolium confusum, is a well-studied model system. However, there is so much variation in the methods and designs of the studies that it is difficult to draw comparisons. This study simultaneously compared several aspects of the infection protocol including beetle age, sex, density and mating status; parasite egg condition, infection environment humidity and the times for the three steps of infection: starvation, feeding and post-feeding development. Although statistically limited by low prevalence and intensity levels, we were able to detect the relative effects of the variables. The effects of these variables on prevalence (percent infection) and intensity (mean number of cysticercoids) do not necessarily correlate with each other. Egg condition, reduced starvation times, higher beetle density and longer development times reduced prevalence. However, differences in intensity were only dete...
This study aims to assess the association of two single nucleotide polymorphisms (SNPs), G34A and... more This study aims to assess the association of two single nucleotide polymorphisms (SNPs), G34A and C376T, in the ABCG2 gene with the risk of developing CRC. To the best of our knowledge, this is the first study that determined the role of genetic variations in the ABCG2 gene with the risk of CRC in Saudi Arabia. The gDNA was extracted from the blood of 58 CRC patients and 48 healthy subjects. The DNA sequencing was used to determine the distribution of genotypes. The results showed that CRC patients carried a heterozygous (GA) genotype for SNP G34A had a low risk of developing CRC (odds ratio=0.015, 95% CI [0.00–0.12]; risk ratio=0.35, 95% CI [0.25–0.12], P <0.0001). On the other hand, patients that carried a heterozygous (CT) genotype for SNP C376T had a high risk of developing CRC (odds ratio=13.83, 95% CI [4.31–44.38]; risk ratio=4.88, 95% CI [1.95–12.24], P <0.0001). In conclusion, the results indicated that a heterozygous (GA) genotype in SNP G34A may decrease the risk of ...
Many species of insects are known to produce and secrete benzoquinone derivatives. These compound... more Many species of insects are known to produce and secrete benzoquinone derivatives. These compounds are usually defined as &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;defense chemicals.&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; However, in many cases, it has not been determined what the chemicals are meant to defend against. Tribolium beetles produce up to three benzoquinones, but their specific function is not known. In this experiment, one of the derivatives, methyl-1,4-benzoquinone (MBQ) was tested for its effectiveness for one of its purported functions as an antimicrobial. Methyl-1,4-benzoquinone was added in three concentrations (0.3, 30, and 150 microg/ml) to the liquid media of three species of Bacillus bacteria and eight species from four genera of yeasts, and the effect on their growth was monitored. The presence of MBQ altered growth in all species. The bacteria responded more negatively than the yeasts. All bacteria species showed reduced growth at all levels of MBQ. Yeasts were more tolerant to the presence of the chemical, and two species, Saccharomyces microellipsoides and Pichia burtonii, actually showed increased growth at the lowest level of MBQ.
To determine the effect that the presence of some beetles have on the species of bacteria found i... more To determine the effect that the presence of some beetles have on the species of bacteria found in their flour. Bacteria were isolated from flour that either did not contain beetles, contained Tribolium beetles in different environments, or contained either Stegobium paniceum or Lasioderma serricorne. These bacteria were tentatively identified by both the gas chromatography-fatty acid methyl esters (GC-FAME) method and partial sequencing of the 16S rRNA gene. All samples contained Bacillus species including the controls, but the non-Tribolium beetles and a Tribolium beetle line known to have low benzoquinones also contained Enterococcus and Enterobacter species. Additionally an unidentified bacteria isolate in the Enterobacteriaceae was also found in the L. serricorne sample. Our results also suggest incongruent identifications when using the GC-FAME method vs sequencing. Certain species of bacteria can be introduced by the presence of insect pests, but the diversity of species is far less in stocks of Tribolium beetles. Stored product pests can alter the bacterial community. Isolated species from this study show a strong genetic relationship to each other, suggesting an isolated evolving system. A unique bacteria was also isolated. GC and sequencing methods of identification are compared.
Many species of insects are known to produce and secrete benzoquinone derivatives. These compound... more Many species of insects are known to produce and secrete benzoquinone derivatives. These compounds are usually defined as &amp;amp;amp;amp;amp;amp;quot;defense chemicals.&amp;amp;amp;amp;amp;amp;quot; However, in many cases, it has not been determined what the chemicals are meant to defend against. Tribolium beetles produce up to three benzoquinones, but their specific function is not known. In this experiment, one of the derivatives, methyl-1,4-benzoquinone (MBQ) was tested for its effectiveness for one of its purported functions as an antimicrobial. Methyl-1,4-benzoquinone was added in three concentrations (0.3, 30, and 150 microg/ml) to the liquid media of three species of Bacillus bacteria and eight species from four genera of yeasts, and the effect on their growth was monitored. The presence of MBQ altered growth in all species. The bacteria responded more negatively than the yeasts. All bacteria species showed reduced growth at all levels of MBQ. Yeasts were more tolerant to the presence of the chemical, and two species, Saccharomyces microellipsoides and Pichia burtonii, actually showed increased growth at the lowest level of MBQ.
Tribolium beetles provide an excellent and easily manipulated model system for the study of genet... more Tribolium beetles provide an excellent and easily manipulated model system for the study of genetics. However, despite significant increases in the availability of molecular markers for the study of genetics in recent years, a significant genetic linkage map for these beetles remains undeveloped. We present the first molecular genetic linkage map for Tribolium confusum using random amplified polymorphic DNA markers. The linkage map contains 137 loci mapped on to eight linkage groups totaling 968.5 cM.
The interaction of the rat tapeworm,Hymenolepis diminuta, with its intermediate beetle host,Tribo... more The interaction of the rat tapeworm,Hymenolepis diminuta, with its intermediate beetle host,Tribolium confusum, is a well-studied model system. However, there is so much variation in the methods and designs of the studies that it is difficult to draw comparisons. This study simultaneously compared several aspects of the infection protocol including beetle age, sex, density and mating status; parasite egg condition, infection environment humidity and the times for the three steps of infection: starvation, feeding and post-feeding development. Although statistically limited by low prevalence and intensity levels, we were able to detect the relative effects of the variables. The effects of these variables on prevalence (percent infection) and intensity (mean number of cysticercoids) do not necessarily correlate with each other. Egg condition, reduced starvation times, higher beetle density and longer development times reduced prevalence. However, differences in intensity were only detected with older beetles. When coupled with survivorship data, our study found that our current infection protocol is optimal for infection success. However, the results suggest extending the study to other intermediate hosts and the inclusion of additional variables.
The interaction of the rat tapeworm,Hymenolepis diminuta, with its intermediate beetle host,Tribo... more The interaction of the rat tapeworm,Hymenolepis diminuta, with its intermediate beetle host,Tribolium confusum, is a well-studied model system. However, there is so much variation in the methods and designs of the studies that it is difficult to draw comparisons. This study simultaneously compared several aspects of the infection protocol including beetle age, sex, density and mating status; parasite egg condition, infection environment humidity and the times for the three steps of infection: starvation, feeding and post-feeding development. Although statistically limited by low prevalence and intensity levels, we were able to detect the relative effects of the variables. The effects of these variables on prevalence (percent infection) and intensity (mean number of cysticercoids) do not necessarily correlate with each other. Egg condition, reduced starvation times, higher beetle density and longer development times reduced prevalence. However, differences in intensity were only dete...
This study aims to assess the association of two single nucleotide polymorphisms (SNPs), G34A and... more This study aims to assess the association of two single nucleotide polymorphisms (SNPs), G34A and C376T, in the ABCG2 gene with the risk of developing CRC. To the best of our knowledge, this is the first study that determined the role of genetic variations in the ABCG2 gene with the risk of CRC in Saudi Arabia. The gDNA was extracted from the blood of 58 CRC patients and 48 healthy subjects. The DNA sequencing was used to determine the distribution of genotypes. The results showed that CRC patients carried a heterozygous (GA) genotype for SNP G34A had a low risk of developing CRC (odds ratio=0.015, 95% CI [0.00–0.12]; risk ratio=0.35, 95% CI [0.25–0.12], P <0.0001). On the other hand, patients that carried a heterozygous (CT) genotype for SNP C376T had a high risk of developing CRC (odds ratio=13.83, 95% CI [4.31–44.38]; risk ratio=4.88, 95% CI [1.95–12.24], P <0.0001). In conclusion, the results indicated that a heterozygous (GA) genotype in SNP G34A may decrease the risk of ...
Many species of insects are known to produce and secrete benzoquinone derivatives. These compound... more Many species of insects are known to produce and secrete benzoquinone derivatives. These compounds are usually defined as &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;defense chemicals.&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; However, in many cases, it has not been determined what the chemicals are meant to defend against. Tribolium beetles produce up to three benzoquinones, but their specific function is not known. In this experiment, one of the derivatives, methyl-1,4-benzoquinone (MBQ) was tested for its effectiveness for one of its purported functions as an antimicrobial. Methyl-1,4-benzoquinone was added in three concentrations (0.3, 30, and 150 microg/ml) to the liquid media of three species of Bacillus bacteria and eight species from four genera of yeasts, and the effect on their growth was monitored. The presence of MBQ altered growth in all species. The bacteria responded more negatively than the yeasts. All bacteria species showed reduced growth at all levels of MBQ. Yeasts were more tolerant to the presence of the chemical, and two species, Saccharomyces microellipsoides and Pichia burtonii, actually showed increased growth at the lowest level of MBQ.
To determine the effect that the presence of some beetles have on the species of bacteria found i... more To determine the effect that the presence of some beetles have on the species of bacteria found in their flour. Bacteria were isolated from flour that either did not contain beetles, contained Tribolium beetles in different environments, or contained either Stegobium paniceum or Lasioderma serricorne. These bacteria were tentatively identified by both the gas chromatography-fatty acid methyl esters (GC-FAME) method and partial sequencing of the 16S rRNA gene. All samples contained Bacillus species including the controls, but the non-Tribolium beetles and a Tribolium beetle line known to have low benzoquinones also contained Enterococcus and Enterobacter species. Additionally an unidentified bacteria isolate in the Enterobacteriaceae was also found in the L. serricorne sample. Our results also suggest incongruent identifications when using the GC-FAME method vs sequencing. Certain species of bacteria can be introduced by the presence of insect pests, but the diversity of species is far less in stocks of Tribolium beetles. Stored product pests can alter the bacterial community. Isolated species from this study show a strong genetic relationship to each other, suggesting an isolated evolving system. A unique bacteria was also isolated. GC and sequencing methods of identification are compared.
Many species of insects are known to produce and secrete benzoquinone derivatives. These compound... more Many species of insects are known to produce and secrete benzoquinone derivatives. These compounds are usually defined as &amp;amp;amp;amp;amp;amp;quot;defense chemicals.&amp;amp;amp;amp;amp;amp;quot; However, in many cases, it has not been determined what the chemicals are meant to defend against. Tribolium beetles produce up to three benzoquinones, but their specific function is not known. In this experiment, one of the derivatives, methyl-1,4-benzoquinone (MBQ) was tested for its effectiveness for one of its purported functions as an antimicrobial. Methyl-1,4-benzoquinone was added in three concentrations (0.3, 30, and 150 microg/ml) to the liquid media of three species of Bacillus bacteria and eight species from four genera of yeasts, and the effect on their growth was monitored. The presence of MBQ altered growth in all species. The bacteria responded more negatively than the yeasts. All bacteria species showed reduced growth at all levels of MBQ. Yeasts were more tolerant to the presence of the chemical, and two species, Saccharomyces microellipsoides and Pichia burtonii, actually showed increased growth at the lowest level of MBQ.
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