|A further article on the fruit fly.|
ScienceDaily (June 14, 2012) — Loyola researchers are taking advantage of a quirk in the evolution of fruit fly genes to help develop new weapons against cancer.
A newly discovered fruit fly gene is a simplified counterpart of two complex human genes that play important roles in the development of cancer and some birth defects. As this fruit fly gene evolved, it split in two. This split has made it easier to study, and the resulting insights could prove useful in developing new cancer drugs.
"Evolution has given us a gift," said Andrew K. Dingwall, PhD, senior author of a paper that describes how his team identified and analyzed the split gene. Their findings are published in the June issue of the journal Development.
When normal cells develop, they differentiate into particular types, such as bone cells or muscle cells, and reproduce in an orderly manner. The process is governed by genes and hormones that work in concert. Two of these genes are known as MLL2 and MLL3. Cancer cells, by contrast, undergo uncontrolled division and reproduction.
Since 2010, a growing number of cancers have been linked to mutations in the MLL2 and MLL3 genes. These cancers include non-Hodgkin's lymphoma, colorectal cancer, kidney cancer, bladder cancer and a brain tumor called medulloblastoma. There also is evidence that MLL2 and MLL3 mutations are involved in breast and prostate cancers.
The MLL2 and MLL3 genes are similar to one another. Each has more than 15,000 building blocks called base pairs -- more than 10 times the number found in a typical gene. Because these genes are so large and complex, they are difficult to study.
In the fruit fly, the counterpart gene to MLL2 and MLL3 split into two genes named TRR and CMI. Each carried information critical for normal gene regulation, and they wound up on different chromosomes. The parsing of the MLL2/MLL3 genetic information into smaller genes in the fruit fly made study of the gene functions much easier; it allowed the researchers unprecedented opportunities to explore the role the human genes play in the development of cancers.
"This fruit fly gene gives us unique insight into the massive human MLL2 and MLL3 genes that are almost impossible to study because they are so large," Dingwall said.
Dingwall's team studied the function of the fruit fly gene by inducing various mutations and then observing the effects on the flies. This will lead to better understanding of what goes wrong when mutations in MLL2 and MLL3 genes trigger the uncontrolled reproduction of cancer cells in humans. This in turn could help researchers develop drugs that would redirect cancer cells to differentiate into normal cells, Dingwall said.
The study was funded through a grant from the National Science Foundation, with additional support from the National Institutes of Health.
Dr. Dingwall is an associate professor in the Oncology Institute and Department of Pathology at Loyola University Chicago Stritch School of Medicine. Co-authors are Claudia Zraly, PhD (joint first author and senior co-author); Chhavi Chauhan (joint first author); Megan Parilla; and Manuel Diaz, MD.
|A fruit fly found in a glass of white wine. This time it was not a call out but in the local pub last night. |
Fruit flies have very quick generation times. This is something that has become very important in human laboratories. Genetic research can be easily carried out when generation times are so rapid. The research teams are making very important discoveries about human evolution with the aid of this small fly.
This is an article on Science Daily about the fruit fly and some of the current research.
Study of Fruit Fly Chromosomes Improves Understanding of Evolution and Fertility
ScienceDaily (Aug. 10, 2012) — The propagation of every animal on the planet is the result of sexual activity between males and females of a given species. But how did things get this way? Why two sexes instead of one? Why are sperm necessary for reproduction and how did they evolve?
These as-yet-unresolved issues fascinate Timothy Karr, a developmental geneticist and evolutionary biologist at Arizona State University's Biodesign Institute. To probe them, he uses a common fruit fly, Drosophila melanogaster -- an organism that has provided science with an enormous treasure-trove of genetic information.
"My research focuses on the evolution of sex and in gamete function," Karr says. "I focus primarily on the sperm side of the sexual equation. I'm interested in how they originated and how they are maintained in populations."
Karr's current study, in collaboration with researchers at the University of Chicago, recently appeared in the journal BMC Biology. The study reexamines an earlier paper that analyzed the sex chromosomes of fruit flies during spermatogenesis -- the process that produces mature sperm from germ cells.
While the previous paper, by Lyudmila M Mikhaylova and Dmitry I Nurminsky, argued against the silencing of sex-linked genes on the X chromosome in Drosophila during meiosis -- a process referred to as Meiotic Sex Chromosome Inactivation (MSCI) -- the reanalysis presented by Karr suggests MSCI is indeed occurring.
The work sheds new light on the evolution of sperm structure and function, through an analysis of Drosophila genes and gene products. As Karr explains, the research has important implications for humans as well: "The more direct, biomedical aspect is that when we learn about the function of a gene that encodes a protein in Drosophila sperm, we can immediately see if there's a relationship between these genes and their functions and known problems with fertility in humans."
Perhaps no other model organism has yielded more insights into human genetics than the tiny fruit fly Drosophila melanogaster. In 1906, Thomas Hunt Morgan of Columbia University began work on D. melanogaster, (one of over 1500 species contained in the Drosophila genus) capitalizing on the species' ease of breeding, rapid generation time and ability to readily produce genetic mutants for study. Morgan's efforts with Drosophila led to the identification of chromosomes as the vector of inheritance for genes, and earned him the 1933 Nobel Prize in Medicine.
Drosophila are yellow-brown in color, have reddish eyes and transverse black rings across their abdomen. Females are about 2.5 millimeters long, while males are slightly smaller and may be easily identified by their darker color.
Most importantly, the similarity in the genetic systems of fruit flies and other eukaryotic organisms including humans makes these model organisms extremely useful analogues for the study of common genetic processes including transcription and translation.
Roughly 75 percent of known human disease genes have recognizable correlates in the fruit fly genome and 50 percent of fly protein sequences have mammalian homologs. (The complete genome of D. melanogaster was completed in 2000.)
Chromosomes: genetic storehouses
Humans have 23 pairs of chromosomes, or 46 chromosomes in all. Of these, 44 are known as autosomes and consist of matched pairs of chromosomes, known as homologous chromosomes. Each homologous chromosome contains the same set of genes in the same locations along the chromosome, though they may appear in differing alleles, which can affect the passing of genetic traits.
The current study however, focuses not on the autosomes but on the remaining pair of chromosomes, known as sex chromosomes. Females contain two X chromosomes, which are homologous, as in the case of the autosomes. By contrast, males are identified as having one X chromosome and one (much smaller) Y chromosome.
While drosophila only have a total of 4 chromosomes, they too display sexual dimorphism, with females carrying the double X chromosomes and males carrying XY. The two X chromosomes in female fruit flies, as in mammals, make them a homozygous sex as compared with the XY condition in males, known as heterozygous.
"There are certain aspects to the composition of these sex chromosomes that have intrigued evolutionary biologists for a long time," Karr notes. One such issue involves an apparent reduction in the number or the level of expression of sex-linked genes on the X chromosome during spermatogenesis. It is believed that this reduction or silencing of genes on the X chromosome may have profound implications for the evolution of sex chromosomes.
During meiotic development of a sperm cell, nature attempts to compensate for the fact that females have two X chromosomes and therefore enjoy a numbers advantage in terms of genes, compared with males. To overcome the bias for female X-linked genes, the X chromosome undergoes inactivation during meiotic sexual differentiation of male gametes, resulting in an underrepresentation of sex-specific genes on the X chromosome. Some of these genes, which may be beneficial to males, are moved from the X chromosome, to the autosomes, where they may be expressed.
The relocation of male-biased genes to the autosomes may be due to a selective advantage favoring genes that move off the X chromosome and therefore avoid X-inactivation during meiosis. Such theories remain controversial however, as statistical analyses are used to evaluate gene frequencies and expression levels, making the proper categorization of genes particularly challenging. "The data we create and generate to support our ideas and hypotheses are messy, there's noise in them," Karr says. "Such noise is inherent in the history of evolution."
In addition to the steady stream of insights into chromosome evolution, Drosophila are being used as a genetic model for a variety of human diseases including Alzheimer's, neurodegenerative disorders, Parkinson's, Huntington's, as well as extending knowledge of the underlying mechanisms involved in aging, oxidative stress, immunity, diabetes, and cancer.
Recourse Pest Control
0800 206 1905
|I attended a call today for moles in a back garden of a domestic premise.|
The owner was concerned about holes appearing in her lawn. She had previously had moles and one was caught via a duffus tunnel trap.
This time however the holes are not from moles. I carefully checked round each hole with the dibber stick but there were no tunnels. The holes had been made by another animal.
The 2 most likely animals to cause such little holes are squirrels or jays (a corvid species). Both animals store nuts and acorns for winter. If you look in the pictures you can see an oak overhanging the garden and acorns around the lawn.
We offer squirrel control but the owner was happy enough knowing she would'nt be getting mole hills. Because only an inspection was carried out no charge was made to the customer. Our call outs are free of charge until work is carried out.
Recourse Pest Control provides pest control to Liverpool, Wirral, Ellesmere Port, Chester and Runcorn.
0800 206 190
|Here are a couple of pictures I took today of rodent chew marks on lagging.|
Rodents teeth grow throughout their lives. They grow from the base of the mouth up. Chewing ensures the teeth are kept at a length that is useful for the rodent. It also keeps the teeth razor sharp as soft dentine is on the inside of the tooth and hard enamel on the outside. The teeth come together in such a way a sharp chisel like edge is maintained.
Rodents can cause massive damage in roof spaces. The most expensive often comes when electrical cabling is chewed.
For rodent control in Wirral, Birkenhead, Ellesmere Port, Chester and Runcorn phone Recourse Pest Control.
0800 206 1905
|This is an article about bedbug control from BASF's website. There is some really interesting information in it.|
Learning from US Bed Bug Control Experience
Dense urban populations, major movements of people and increasing restrictions on residual insecticides have contributed to a major resurgence in North American bed bug problems in recent years. Add to this an alarming level of resistance to key insecticides and it not difficult to see why a good 75% of US pest controllers rated bed bugs as their single most difficult-to-control pest in the benchmark 2010 National Pest Management Association (NPMA) study with the University of Kentucky.
That this has risen from less than 60% in an almost identical survey conducted in 2008 underlines the scale of the recent increase in the US bed bug challenge. As does the growing extent to which infestations are being reported in every conceivable location Click to view (Figure 1).
“The recognition that bed bug infestations can extend well beyond bedrooms is vital for pest controllers everywhere,” stresses BASF Pest Control Solutions’ insect management specialist, Roland Twydell. “It highlights the fact that the pest can be carried over great distances on luggage, clothing and second-hand furniture, amongst other methods. And it underlines the importance of extending inspections and, if necessary, treatments to other parts of premises found to be infested and, indeed, to locations not normally associated with the pest.
“Thankfully, US public concerns over the use of pesticides to treat bed bugs appear to have declined markedly as problems with the pest have grown. In 2008, for instance, pest control companies reported just under 60% of their customers were ‘not very’ or ‘not at all’ concerned about applying insecticides to control bed bugs. By last year’s survey this had grown to comfortably over 90%.”
This is just as well since insecticide sprays and dusts remain overwhelmingly central to successful bed bug treatment. What is more, over 80% of US pest controllers now use insecticides on beds and three quarters spot treat mattresses as well as box springs – a marked turn-around from the past reluctance of most people to have beds treated.
While synthetic pyrethroids continue to be widely employed in US bed bug control, growing resistance problems have led to a significant shift in active ingredient use over the past two years.
Despite research showing zero mortality to 10 times the label rate of deltamethrin in 14 of 16 bed bug populations from eight different states, a product based on this active remained the most widely used insecticide in 2008. By 2010, however, this had been comprehensively displaced by Phantom®(chlorfenapyr) proven to be highly effective against resistant as well as susceptible populations Click to view (Figure 2).
“Only approved for controlling the pest in 2006, chlorfenapyr in the form of Phantom® has rapidly become the first choice US bed bug insecticide for its non-repellent, non-irritating and virtually odourless nature as well as its resistance-beating mode of action,” points out Roland. “Although not yet registered in the UK, the new active is being increasingly employed this side of the Atlantic over the past year, following the approval of the first European formulation, Mythic® in both Germany and France.
“Top quality products like Fendona® (alpha cypermethrin) – preferred in the UK for the superior activity and extended residuality of the suspension concentrate formulation, is widely considered to be one of the best alternative partners.”
Equally important in the fight against bed bugs, US controllers recognise, is the application of sprays as precisely and thoroughly as possible within infested areas, their combination with other physical controls and, above all, the maintenance of sufficient treatment pressure over time.
In apartments, for instance, detailed survey work has highlighted a wide range of common bed bug hiding spots, more than a quarter of which are beyond the bed itself Click to view (Figure 3).
“Spraying clearly has to target all these areas if beds are not to be rapidly re-infested from other harbourages in the immediate vicinity,” Roland Twydell notes. “Which, in most cases, will necessitate substantial movement, if not dismantling, of furnishings.
“The sheer scale of inspection and treatment work required means many initial US bed bug treatments are currently taking five hours or more, with an average of between two and three treatments needed to get an infestation under control.
“Both the amount of time per treatment and number of treatments required increase markedly with the degree of clutter in the environment. Indeed, over half of pest controllers reckon it takes more than three treatments for effective control where the environment is cluttered. This compares with less than 10% in uncluttered surroundings.” Click to view (Figure 4).
US professionals insist that success also depends on removal of visible bugs ahead of spraying by thorough vacuuming, together with sufficient co-operation from customers and tenants in removing, laundering and, if necessary, disposing of infested mattresses, bedding and other soft furnishings.
Many are further finding it better to work in teams, or at least have assistance available to help dismantle beds and move furniture to enable jobs to be undertaken thoroughly enough within the time available.
Under these circumstances, Roland Twydell finds it hardly surprisingly that, rather than relying on their standard pest control terms, the majority of US companies now employ separate contracts for bed bug treatment.
“As well as accounting for the fact that treatments generally take far longer than other pests and tend to require substantial amounts of insecticide – often more than 3.8 litres for a typical apartment – specific bed bug contracts are valuable in setting out clear customer responsibilities and protecting operators against the growing threat of litigation,” he says.
|A narrow escape for me in Chester Zoo!!! |
I'll have to order a new coat....
Recourse Pest Control does not
provide control for dinosaurs
A mouse nest I found today in a roof space in Otterspool, Liverpool. The owner had reported noises in the roof above her bed. No droppings or other evidence were found in the house itself.
On inspection of the roof space a few scattered droppings were found.
Approaching the area above the customers bed I could here a faint squeak. On inspection of the area a mouse nest was found in the insulation.
5 baby mice were found and removed. The nest was replaced with rodenticide bait for the return of the mother mouse. A follow up will be carried out next week.
For mouse control in Liverpool, Wirral, Chester, Ellesmere Port and Runcorn phone Recourse Pest Control.
0800 206 1905
|Starlings often can cause a nuisance in places they roost. A large colony of birds can produce a vast amount of droppings in one night causing damage to buildings and structures.|
In this call today the bird had not been roosting. Individuals have been getting trapped over the course of a few years. 9 starling bodies were found in this roof space. The bodies were initially found when a contracter entered the roof space to fit new insulation.
Each bird had a different state of decomposition indicating different times of death. The birds were removed and the roof space disinfected.
No obvious entry points were found. Its likely the birds have entered under the eaves when looking for insects in the gutters. Proofing of the house can be carried out using mesh to block the gaps under the eaves.
Phone Recourse Pest Control for dead animal removal and bird proofing.
0800 206 1905
|The myths about bedbugs as discussed in Scientific American;|
Myth 1: Bedbugs can fly
Bedbugs lack wings, and therefore cannot fly. That is unless you put a blow dryer behind them, says Stephen Kells, a bedbug researcher at the University of Minnesota. Then they'll fly about 1.2 meters. On their own, bedbugs crawl about a meter a minute, he says.
Myth 2: Bedbugs reproduce quickly
Compared with other insects, bedbugs are slow to reproduce: Each adult female produces about one egg per day; a common housefly lays 500 eggs over three to four days. Each bedbug egg takes 10 days to hatch and another five to six weeks for the offspring to develop into an adult.
Myth 3: Bedbugs can typically live a year without a meal
Scientists debate this point, but evidence suggests that at normal room temperature, about 23 degrees Celsius, bedbugs can only survive two to three months without a blood meal. But because they are cold-blooded, their metabolism will slow down in chillier climates, and the insects may live up to a year without feeding.
Myth 4: Bedbugs bite only at night
Although bedbugs are generally nocturnal, they're like humans—if they're hungry, they'll get up and get something to eat. "If you go away to visit a friend for a week and you come back and sit down on the couch, even though it's daytime the bedbugs will come looking for you," Schal says. Keeping a light on, then, unfortunately does not keep these tiny vampires away.
Myth 5: Bedbugs live exclusively in mattresses
"'Bedbug' is such a misnomer," Kells says. "They should also be called pet bugs and suitcase bugs and train bugs and movie theater bugs." Bedbugs spread away from beds into living areas and can be seen on any surface, he says, including chairs, railings and ceilings.
Myth 6: Bedbugs prefer unsanitary, urban conditions
"Bedbugs are terribly nondiscriminatory," Schal says. Bedbugs can be found anywhere from ritzy high-rises to homeless shelters. The prevalence of the bugs in low-income housing is therefore not a result of the insect's preference, but of dense populations and the lack of money to pay for proper elimination strategies. "Any location is vulnerable," Kells says. "But some people are going to have a harder time getting control of them because it is such an expensive treatment."
Myth 7: Bedbugs travel on our bodies
Bedbugs do not like heat, Kells says. They therefore do not stick in hair or on skin, like lice or ticks, and prefer not to remain in our clothes close to our bodily heat. Bedbugs are more likely to travel on backpacks, luggage, shoes and other items farther removed from our bodies.
Myth 8: Bedbugs transmit disease
Bedbug bites can lead to anxiety, sleeplessness and even secondary infections, but there have been no reported cases of bedbugs transmitting disease to humans. They do, however, harbor human pathogens: At least 27 viruses, bacteria, protozoa and more have been found in bedbugs, although these microbes do not reproduce or multiply within the insects. Canadian researchers announced (pdf) in the June issue of Emerging Infectious Diseases that bedbugs isolated from three individuals in a Vancouver hospital carried methicillin-resistant Staphylococcus aureus, aka MRSA. Still, there have been no reported cases that the bugs actually transmit human disease.
Myth 9: We should bring back DDT
When the controversial pesticide DDT was banned in 1972, most bed bugs were already resistant to it, Schal says, and today's populations are even more widely resistant thanks to the use of a new class of pesticides. Pyrethroids, the main class of pesticides used against bedbugs today, targets sodium channels in bedbug cells, just like DDT. Consequently, as bedbugs develop resistance to pyrethroids, they also become cross-resistant to DDT.
Myth 10: You can spray bedbugs away
Thanks to pesticide resistance, those cans of spray at your local hardware store simply will not do, Schal says, adding: "Relying strictly on chemicals is generally not a good solution." The most effective solutions are fumigation and heat treatments, but these can cost a cool $2,000 to $3,000 apiece for a single-family home. Scientists are diligently pursuing other strategies, including freezing and bait similar to that used for cockroaches. In the October 2010 issue of the Journal of Economic Entomology Schal and colleagues at the U.S. Department of Agriculture published a technique that employs inexpensive infrared and vibration sensors to track bedbug movement, which could be applied to the development of automated traps that detect the pests.
|Bedbug hiding place diagram.|
This diagram shows places that bedbugs will hide around your bedroom. All areas must be treated to control the infestation. Any areas missed can cause insects to survive and reinfest your house.