In many cases super avana 160 mg sale impotence what does it mean, people are reporting the presence of anthrax that turns out to be a false alarm super avana 160 mg for sale erectile dysfunction drugs dosage. The director will need to prioritize the cases that come in to determine which leads may best point to the person who is distrib- uting the anthrax order super avana 160 mg visa erectile dysfunction effects on women. It is also imperative that medication for treating anthrax is available to hospitals and medical treatment centers that may need it for anyone infected. The communication plan is to keep in con- tact with the other federal agencies as well as state and local ofcials. It is important for the director to reassure the public that the issue is being inves- tigated and that medication for contending with anthrax is being disbursed to medical centers. Stage 3 of the Disaster Two letters that have a more refned grade of anthrax are mailed to U. The director should see if the sample of anthrax sent to the senators has the same characteristics as the earlier samples. Postal Service to deter- mine if there is any method or equipment that can be used to detect biotoxins in the U. The director must give the public regular updates on the investigation and serve to reassure the public that the government is conducting a full investigation on the matter. Key Issues Raised from the Case Study Tere were a few shortcomings evidenced in this case study. The absence of con- trols at the laboratory where the weapons-grade anthrax was taken from has to be Case Studies: Other Terrorist Events ◾ 169 a primary question for governmental ofcials. How did someone remove the bio- toxin from the laboratory without detection, and what controls should have been in place to prevent this action from occurring? The case study scenario also shows how vul- nerable a critical infrastructure was to a biotoxin attack. Postal Service, the perpetrator essentially used a public mode of delivery to launch an unconventional weapon attack across a large segment of the country. Administrators need to ensure not only that proper controls are in place, but also that they are being followed. With dangerous items that can be weaponized, inventory control is vital in order to protect the research facilities and personnel, but also to protect the public at large. Postal Service from an attack such as a biotoxin, since it is difcult to detect (unlike radiation or certain types of chemicals). Terefore, it is prudent to have on hand medical resources to contend with such an event since there is a possibility for individuals to be infected if a biotoxin of that nature is present. A number of people died from anthrax infections and more than 20 people were infected by the select agent. Additionally, there were a number of times where detection of anthrax led to shutdowns of diferent government buildings (i. The threat of anthrax infection was enough to stop all business at these government facilities until the locations were sanitized. September 11, 2001 Stage 1 of the Disaster You are a federal administrator for an agency that is responsible for respond- ing to a terrorist attack. The administrator needs to make sure that all aircraft currently in the air are accounted for. If a plane is not responsive, this information needs to be relayed to military bases where fghter planes are located, and the executives in the federal government need to be noti- fed immediately that a potential situation exists where terrorists may have hijacked more than one aircraft. The administrator needs to estab- lish communication links to the aircraft currently fying. In addition, the administrator needs to confrm and verify that he or she has authority to take action in case terrorists have taken over a fight. If current status cannot be verifed or confrmed, the admin- istrator should verify the authority he or she has to contend with such a situation. If the authority is given to contend with the situation, then fght- ers should be sent to intercept any aircraft that cannot be contacted. Until the situation is resolved, all fights should be kept on the ground until fur- ther notice. Stage 2 of the Disaster Two F-15s are scrambled to intercept Flight 11, but this plane has already hit the World Trade Center. The F-15s are sent into a holding pattern around New York when Flight 11 cannot be located. The diferent agencies of the federal govern- ment should be contacted as well as the Department of Defense to request an intercept of Flights 175 and 77 by fghters that are currently on standby over New York. The administrator will need the proper authority to take action on the fights that are suspected of being hijacked. Since there are at least two known fights that are suspected of having the crew killed, there will need to be fghters to intercept this aircraft immediately. People are stumbling out of both World Trade Center buildings and in some cases are jumping out of windows due to the fres that are raging out of control. The administrator should keep attempting to contact any aircraft that are still in the air and have the crews be alert for a possible hijacking. The White House should be notifed about the actions that have transpired and notifed that Flight 93 appears to be under terrorist control. The administrator should make every efort to fnd out what aircraft can land at the nearest location to get as many planes out of the sky as possible. Tis will allow the administrator to focus on only aircraft that could have been potentially taken over by terrorists as a threat. The aircraft that do not respond can then have fghter jets intercept them to either force them to land or shoot them down. You have a number of people that are trapped in rubble and the debris (National Institute of Standards and Technology, 2005). At this point the administrator should have a very clear count on how many aircraft are still in the air that could be a potential threat. International fights should be escorted in via fghter jets since there 172 ◾ Case Studies in Disaster Response and Emergency Management may or may not be enough time to verify if the aircraft are under control of the crews and most of the international fights head toward big cities with major landmarks. The federal agencies that are impacted by air travel should be briefed on the situation. The administrator should also brief the public on the events as they have unfolded and assure the public that an investigation is underway to prevent occurrences of this nature from hap- pening in the future. Key Issues Raised from the Case Study In part, poor controls of student visas granted to international students allowed for several of the terrorist students to stay in the United States past the deadline of their visa expiration dates. Whether or not active tracking of those individuals by the government would have averted this particular crisis will always be debatable. What is not debatable is that a small number of individuals were able to take over four diferent airlines using an assortment of weapons (e. The failure to detect the makeshift weapons was a clear defect in airport security screening, which gave the individuals on board a commercial aircraft the means to take con- trol of four airliners. Aircraft being used by terrorists as a terror weapon was a new concept to public ofcials.
The left hand panel shows the thickened leaflets order 160mg super avana mastercard impotence kidney, but the precise mechanism is unclear discount super avana online master card where to buy erectile dysfunction pump. The image on the left shows the two atrioventricular valves from above during systole buy discount super avana online erectile dysfunction causes pdf, while the one on the right shows the mitral valve from below. The Mitral Valve in Congenitally Corrected Transposition of the Great Arteries Although the major atrioventricular valve pathology involves the morphologic tricuspid valve, abnormalities of the mitral valve are encountered fairly frequently (41). It is important to recognize these abnormalities, as they can have a profound effect on outcome when a double switch or atrial switch and Rastelli pathway is chosen. There may be mitral valve leaflet dysplasia, multiple papillary muscles, an associated cleft, or a straddling mitral valve (Fig. Three-dimensional echocardiography provides superior evaluation of the morphologic mitral valve. The cleft, shortened chordae, and multiple papillary muscles are readily identified. In some cases the valve is competent at presentation, however when an anatomical repair is performed, the mitral valve is unable to accommodate the associated systemic pressure. Unlike the normal mitral valve which can cope with left ventricular dilation in the setting of normal left ventricular function many of these valves cannot due to the pathologic abnormalities mentioned above. Straddling of the Mitral Valve This is an important lesion to identify and invariably occurs in hearts with an abnormal ventriculoarterial connection, in particular ventriculoarterial discordance or double outlet right ventricle with an anterior aorta. The aortic or anterior leaflet is always involved with chordal apparatus from that leaflet having variable attachments within the right ventricle. In some instances they insert into the crest of the interventricular septum while in others they insert into a papillary muscle on the proximal or distal interventricular septum (Fig. Of note there is invariably an associated cleft in the mital valve with an eccentric orifice, pointing more toward the ventricular septal defect. The mitral valve is usually competent due to the chordal support, however recognition is important, because if the chordae are inadvertantly cut during repair, the valve will become regurgitant. Although two- dimensional echocardiography has superior temporal resolution making identification of fine chordal structures more accurate, inferior spatial resolution can impede precise location of the abnormal chordae. As the mitral valve and its straddling chords insert in an anterior location, they are readily identified in a full volume data set obtained from the parasternal long-axis view. Precise location of the straddling mitral valve at its site of insertion is important, as this dictates whether a biventricular or single ventricle operative pathway is followed (42). Hemodynamic Assessment of the Mitral Valve In the current era echocardiography provides most of the hemodynamic information that is necessary to make a clinical decsion with regard to intervention and its timing. This impacts on mean gradient evaluation, which is also dependent on cardiac output. Despite this, it is an invaluable measurement in pediatric patients, whereas pressure half-time is difficult to interpret due to the higher heart rates of children compared to adults (43). It is also possible to obtain an estimation of mitral valve area by planimetry from three-dimensional echocardiography (Fig. As well, tricuspid or pulmonary regurgitation jets can be used to assess right ventricular and pulmonary artery pressure, which is often increased due to left atrial hypertension. The two lower images show the mitral chords inserting into a papillary muscle, however the precise location is unclear. The upper right hand image is similar to the upper left one, but with slight angulation to show the anterior muscular ventricular septal defect with the chordae from the mitral valve (arrows) inserting into it. B: This is from the same case as (A) and shows the anterior muscular ventricular septal defect, as well as a second smaller perimembranous defect (arrows). The image on the left is with partial cropping of the heart, while the one on the right views the ventricular septal defect from in front from the right ventricle. The precise location of the papillary muscle which the mitral valve is attached to in the right ventricle is seen. The lower right hand image shows the component of the mitral valve which inserts into the right ventricle (black arrow). The lower right hand image is the reconstructed three- dimensional view which shows the straddling component of the mitral valve as well. The lower trace shows the right ventricular pressure from tricuspid valve regurgitation. The lower right hand panel shows the true mitral valve orifice (arrow) as seen from the left atrium with three- dimensional echocardiography. Assessment of Mitral Valve Regurgitation Vena Contracta Size We have already discussed the role of three-dimensional echocardiography in the evaluation of both the site and severity of mitral valve regurgitation. Certainly, this technique provides superior data with regard to the site of regurgitation, and can be incorporated into surgical decision making. The advantage is that the valve can be seen as a whole, and commissural and central regurgitant jets pinpointed (see Fig. This is understandable as two-dimensional color techniques presume that the jets are circular in shape. Of interest, for the tricuspid valve, although there is a good correlation between vena contracta width by two- dimensional echocardiography and vena contracta area by three-dimensional echocardiography, only the latter has been shown to be predictive of outcome using multivariate analysis (48). Despite this, it is still not widely utilized and clinical utility needs to be established in large adult series where it can be related to outcome and volumetric measurements of regurgitation. Left Atrial and Left Ventricular Size These are good indicators of the severity of regurgitation and indeed left ventricular end-systolic dimension is considered when determining optimal timing for surgical intervention in those with primary mitral valve disease (49). This is not the case in patients with associated left to right shunt lesions such as a ventricular septal defect or patent arterial duct, which affect not only chamber size but also flow dynamics through the mitral valve. The main lesion that might be confused with primary mitral valve regurgitation in the young population is regurgitation associated with anomalous left coronary artery, which results in subendocardial ischemia and papillary muscle dysfunction. The image on the left shows the sclerotic anterior papillary muscle, indicated by the black arrow. Pulmonary Venous Doppler Pattern Systolic flow reversal can be seen in cases with significant regurgitation, however it is important that more than one pulmonary vein is sampled, as a jet may be directed into one particular pulmonary vein (50) (Fig. Limitations to this approach relate to the presence of diastolic dysfunction with raised left atrial pressure and blunted systolic forward flow. Continuous Doppler Regurgitant Jet Profile The more severe the regurgitation, the denser the continuous wave Doppler profile (see Fig. This is of limited value, however, given that increased gain settings can enhance a Doppler signal. Mitral E Velocity Dominance A dominant pulsed Doppler E profile is seen in those with severe mitral valve regurgitation. Once again this will be affected by those cases with associated diastolic dysfunction (Fig. These are techniques that are widely utilized in adult populations and indeed play an important role in decision making (51).
This can result in high levels of protein expression by allowing protein synthesis to continue for long periods of up to 24 h (Martin et al order 160 mg super avana with amex erectile dysfunction vitamin. Structural genomics promises to increase greatly our knowledge of the types of protein fold that polypeptides may adopt order super avana 160mg amex erectile dysfunction at age 25. Efforts will still be required to analyse biologically interesting buy super avana now otc erectile dysfunction pills that work, but structurally difﬁcult, proteins. Engineering la nts 1 Key concepts Plants are attractive targets for genetic modiﬁcation, given their commercial importance Genes can be inserted into a variety of dicotyledonous plants by modifying the Ti plasmid from Agrobacterium tumefaciens. The manipulation of genes in higher eukaryotes offers the opportunity to alter gene expression within a whole organism. For example, the altering of the protein composition of plants to make them more nutritious or able to grow in difﬁcult circumstances or to impart them with properties to make them more desirable to shoppers has potentially enormous Analysis of Genes and Genomes Richard J. One of the major differences between plant and animal cells is that plants retain a high degree of plasticity. That is, an isolated plant cell under appropriate culturing conditions can have the capability of regenerating an entire new plant. This ability has proved vital for the production of engineered plants since individual cells, either as cell cultures or other forms, can be manipulated and then used to reform an intact plant. How- ever, a bacterial plasmid, the tumour inducing (Ti) plasmid of the soil microorganism Agrobacterium tumefaciens, has been used extensively to intro- duce genes into plant cells. A wound on the stem of the plant allows the bacteria to invade and cause a cancerous proliferation of the stem tissue. A plasmid carried within the bacterium is responsible for its ability to cause crown gall disease (Zaenen et al. This tumour inducing (Ti) plasmid is large (∼200 kbp) and carries a number of genes that are required for the infection process (Figure 11. Other soil bacteria are unable to metabolize opines, and thus these molecules serve to promote the growth of more Agrobacterium cells, and may provide a selective advantage to Agrobacterium over competition from other microorganisms present in the soil. Crown galls formed by the invasion of Agrobacterium tumefaciens into wounds on the stem of a potato plant. Additionally, the crown gall produces opines – modiﬁed amino acids, like nopaline shown below – which can be used by Agrobacterium as a source of metabolites Cytokinin Auxin synthesis Opine synthesis synthesis Left Right border N border Ti plasmid ~200 kbp Virulence genes Opine utilisation Agrobacterium ori Figure 11. The recombination takes place through a homologous region present in both of the plasmids (Matzke and Chilton, 1981). The transformation of plants using modiﬁed Agrobacterium Ti plasmids, like the transformation of E. Most vectors used today contain a selectable marker gene between the left and right border repeats for transformant identiﬁcation. This is commonly the kanamycin-resistance gene (see Chapter 3), but may also be a gene required for resistance to other antibiotics or herbicides. For example, the csr1-1 gene from Arabidopsis, encoding a form of the enzyme acetolactate synthase, renders plants resistant to sulphonylurea herbicides such as chlorsulphuron (Haughn et al. As we will discuss later, however, the introduction of resistance genes into plants has caused widespread concern about their dissemination into the environment. Plant transformation using Agrobacterium is most commonly performed using leaf tissue (Horsch et al. Small discs are taken from the leaf, using a paper punch, and incubated with the recombinant Agrobacterium. The infected leaf disc is transferred to a medium containing high levels of cytokinins to induce shoot formation prior to incubation with a mixture of the antibiotics kanamycin and ampicillin – to both select for the transformed plant cells and kill the bacteria. Agrobacterium has proved to be an incredibly useful tool for the insertion of genes into plants (Hooykaas, 1989), but its scope is limited to plants that can be infected by the bacteria. Monocotyledonous plants, such as wheat, barley, rice and maize, are attractive targets for genetic manipulation, but are generally resistant to Agrobacterium infection. Agrobacterium mediated transformation of rice can occur at high frequency if acteosyringone, a phenolic compound produced by wounded dicotyledonous plant tissues, is included in the transformation reactions (Hiei et al. Another difﬁculty with Agrobacterium mediated transformation is the requirement to regenerate intact plants from cell cultures. The ease with which this can be achieved is species dependent and can form a major stumbling block to the generation of transgenic plants. The promoters from the Agrobacterium opine synthesis genes have been widely used to generate high levels of transgene expression that is inducible by wounding (An, Costa and Ha, 1990). Additionally, a number of promoters have been used to direct the expression of genes in particular tissues. For example, the promoters from several seed storage proteins can be used to target gene expression in the seeds only (Schubert et al. Other factors, in addition to promoter strength, also play a role in dictating the levels to which transgenes can be expressed. The expression of the transgene will generally occur to higher levels if 5 untranslated sequences and an intron are included within the transgene, and a polyadenylation site is located at its 3 -end. Much of this appears to be a result of the location into which the transgene has integrated. The non-homologous recombination that is required to insert a foreign gene into the plant genome means that the foreign gene is inserted randomly. Additionally, the random nature of the integration event often results in multiple copies of the transgene being inserted into the plant genome – either in the form of tandem repeats at a single locus, or scattered throughout the genome of the plant. Rather than increasing the levels at which the foreign gene is expressed, this can lead to silencing of the transgene so that it is not expressed at all (Plasterk and Ketting, 2000). The multiple repeats were expressed very poorly, but if the Cre recombinase was also expressed in the cell (to recombine the loxP sites and eliminate all but one of the gene sequences) then the transgene was highly expressed. Attempts have been made to develop a system for targeted transgene insertion into plants through the introduction of elements of a homologous recombination system, e. In plants, this can be achieved by treating tissue with pectinase and cellulase enzymes to, respectively, break up cell aggregates and digest away the cell wall. Protoplasts will synthesize a new cell wall within 10 days, after which they are capable of undergoing cell division and, under appropriate conditions, the regeneration of new plants. Particle acceleration may be achieved using gun-powder, electrical discharges or pressurized gas. We have seen previously how bac- terial viruses have been exploited to introduce genes into bacteria (Chapter 3). The genome is packaged into coat proteins, which, as for bacteriophage λ, introduces restraints on the size of recombinant genomes that can be produced that retain the ability to be infective (Figure 11. With the removal of two non-essential viral genes, the maximum insert size is still less than 1 kbp. Each image is at 300 000 × magni- ﬁcation, and is reproduced from the following web site: http://www. This led to the speculation that geminiviruses could serve as relatively stable transient gene expression vectors – which is particularly important since they infect many crop plants (Stanley, 1993). Geminiviruses, however, tend to undergo high levels of gene rearrangement and deletion during their infective cycle, which is highly undesirable for a cloning vector. This allows for the insertion of multiple foreign genes into the chloroplast that can be expressed from the same polycistronic transcript. The chloroplast is highly polyploid – each chloroplast may contain multiple copies of the genome – and photosynthetic cells may contain many thousands of chloroplasts.
O. Lester. Lincoln College.