Staphylococcus Aureus Infection In Humans Essay Example For College

Classification and Morphology

The genus Staphylococcus has various species, which are mainly divided depending on their ability to cause clotting of the blood plasma. This process is referred to as the coagulase reaction. Staphylococcus aureus is coagulase-positive, implying they cause clotting. The organisms are mainly found in the axillae and nasal cavities of humans existing as commensals. A quarter of humans and animals are estimated to host the pathogen in these parts of the bodies (Tong, Davis, Eichenberger, Holland, & Fowler, 2015). The aureus species is the most pathogenic in the particular genus.

Staphylococcus aureus is a gram-positive bacterium. Its shape is a coccus which usually is clustered together in a grape-like form. Each bacterium has a diameter of approximately one micrometer. At times, the cocci can also be found in chains or pairs. Their ability to grow in clumps is an identification test following culture in the laboratory. This formed the basis of their index identification by Sir Alexander Ogston, a surgeon. After culturing a pus sample from an abscess of the knee joint, he described that they looked like bunches of grapes.

Due to the potential of the bacteria to cause infections in both the community and the hospital, typing the samples is necessary during investigations of related disease outbreaks. The typing processes employed should be easily replicable and also show ease of use and interpretation.

The previous method of typing was phage-typing. The marker that the test is founded on is not easily reproducible and requires maintenance of large amounts of phages, limiting the typing to few specialized laboratories. This heralded the use of molecular typing methods that mainly analyze restriction fragment length polymorphisms. The best method currently employed is the field gel electrophoresis (Tong et al., 2015). The bacterial DNA is spliced into large fragments by restriction enzymes.

Pathogenesis

In humans, the skin acts as the initial barrier against bacterial infections. Keratin, produced by keratinocytes, is at the foundation of this protective function. The occurrence of trauma renders the individual susceptible as pathogens gain entry to the underlying tissues (Kobayashi, Malachowa, & DeLeo, 2015). Another protection mechanism is the involvement of polymorphonuclear neutrophils (PMNs). They form the primary cellular defense against bacterial infection. This role is carried out through phagocytosis. It can be followed by the destruction of the pathogen using reactive oxygen species and other degradative enzymes.

The pathogenesis of Staphylococcus aureus is dependent on its ability to subvert these protective mechanisms. The bacteria produce immune evasion molecules, cause lysis of PMNs, coagulase enzymes, and cytotoxins. The pathogen releases N-formyl peptides. These peptides are chemotactic and attract PMNs. However, the staphylococcal pathogen has developed chemotactic inhibitory proteins that prevent the accumulation of neutrophils within affected regions. Some of the leukocytes reach the site of infection. They encounter cytolytic toxins that destroy them, effectively limiting the response of the immune system.

The bacteria also produce protein A. This molecule binds to the Fc region of the immunoglobulin G, hence preventing opsonization of the pathogens. This implies that they cannot be targeted for destruction, ensuring their survival. Another anti-phagocytic molecule is clumping factor A which binds to fibrinogen in the blood and deposits it on the bacterial surface (Kobayashi, Malachowa, & DeLeo, 2015).

The pathogens have evolved to formulate mechanisms that prevent destruction by reactive oxygen species produced by leukocytes. The enzymes reductase, catalase, alkyl hydroperoxide, and superoxide dismutase protect them from this risk. Staphyloxanthin, the staphylococcal pigment, has antioxidant properties, further augmenting the role of these enzymes. Due to the ability of the bacteria to cause cytolysis of the PMNs, the cytotoxic molecules are released from these inflammatory cells into the tissues.

This results in the destruction of the surrounding tissues, hence the characteristic feature of the staphylococcal organisms to cause the formation of abscesses. These leukocytic factors include alpha-hemolysin, leucocidin, and gamma-hemolysin. Alpha-hemolysin is closely linked with the development of Staphylococcal skin infections.

The bacteria have superantigens, toxic shock syndrome toxin (TSST), and enterotoxins. Superantigens cause widespread stimulation of the immune system without the involvement of formal recognition of antigens. Large amounts of cytokines are released, causing the symptoms and signs of toxic shock syndrome. The final pathogenic factor is an exfoliative toxin. It shows proteolytic activity, causing blistering and loss of the epidermis.

Symptoms of Infection

The main entry of the organism is broken skin. It leads to the formation of abscesses that are pus-filled lesions.

The abscesses can be classified into pustules, furuncles, and carbuncles in order of increasing size.

The organism causes impetigo, which is found mainly in young children. It is a superficial, blister condition that primarily affects the face and limbs.

Cellulitis. The pathogen is responsible for the widespread inflammation of the dermis and underlying connective tissue.

Accidental and post-operative wound infections.

The organism may be disseminated through the body via the blood, causing the following conditions septic arthritis, endocarditis (mainly in intravenous drug users), osteomyelitis, meningitis, and septicemia. The conditions instigated by its toxins include toxic shock syndrome, scalded skin syndrome, and staphylococcal food poisoning (Center for Disease Control and Prevention, 2018).

Laboratory Identification and Diagnosis

Clinical specimens are grown on blood agar. The examples include pus swabs, sputum, blood, feces, and nasal swabs. Following culture, the bacteria produce opaque, raised, round colonies that are at least a millimeter in diameter (“Lab 15,” 2019). They are beta-hemolytic and have creamy gold colonies. They are sensitive to novobiocin. On Gram staining, they are positive and found in clusters. They are able to grow on mannitol salt agar and are coagulase positive. They are also favorable for clumping factor and protein A. In the laboratory, they are also assessed for sensitivities to the various antibiotics used in the treatment of staphylococcal infections.

Treatment and Antibiotic Resistance

Initially, the pathogens were susceptible to penicillin, especially methicillin. Penicillins act by inhibiting cell wall synthesis. They work on peptidoglycans; hence, gram-positive bacteria are sensitive to their action causing lysis of the bacterial organism.

For staphylococcal skin infections, management involves incision and drainage for superficial infections. Antibiotics are employed in severe disease, which fails to respond to the previous intervention.

Over time, the organism has gained adaptations to subvert the actions of penicillin. This resistance can be easily transmitted to other bacteria through plasmids, thus limiting the effectiveness of these drugs. Alternative drugs for treatment include trimethoprim-sulfamethoxazole, doxycycline, vancomycin, and clindamycin (Tong et al., 2015). Methicillin-resistant Staphylococcus aureus is treated mainly using vancomycin or linezolid. Vancomycin-resistant strains are treated using a combination of quinupristin-dalfopristin or linezolid.

Due to the ability of the pathogen to rapidly develop resistance against antibiotics, other therapies such as vaccination have been broached to manage the infections. However, human trials have been unsuccessful so far.

Infection can be prevented through handwashing and proper cleansing of both surgical and other traumatic wounds. The use of indwelling catheters should also be done in an aseptic manner. Antimicrobials should be used sparingly and appropriately to prevent the development of resistance.

References

Center for Disease Control and Prevention. (2018). Staphylococcal (Staph) Food Poisoning. Web.

Kobayashi, S., Malachowa, N., & DeLeo, F. (2015). Pathogenesis of Staphylococcus aureus abscesses. The American Journal of Pathology, 185(6), 1518-1527. Web.

Lab 15: Isolation and Identification of Staphylococci. (2019). Web.

Tong, S., Davis, J., Eichenberger, E., Holland, T., & Fowler, V. (2015). Staphylococcus aureus Infections: Epidemiology, pathophysiology, clinical manifestations, and management. Clinical Microbiology Reviews, 28(3), 603-661. Web.

Joe Biden’s Public Speaking Skills Critique

Delivery of Information

The candidates participating in the presidential debates presented some informative speeches. In this paper, the speaking skills of Joe Biden will be analyzed and critiqued in compliance with such aspects as delivery, organization, and confidence. As for the quality of information delivery, the speaker showed competence in articulated issues. His answers to the questions were concise, to the point, and well-developed. Since the goal of the participation in the debates is to inform and persuade the voters by providing them with clear perspectives about future policies, Biden succeeded in the accuracy of message delivery. His utterances were easily perceived and grounded on reliable data. The speaker addressed the audience several times, thus personalizing the communicated issues as ones relevant for every citizen of the USA.

Organization

The speech was well-organized, and the topics under discussion were well-developed. When answering questions, Biden accurately addressed the necessary points to provide comprehensive responses. His utterances were clearly structured, and their parts were often introduced in strict order. Thus, using such words as, firstly, secondly, and similar ones indicating the organization of the message, the speaker managed to be understood by his interlocutors and the audience.

Confidence

Throughout his speech, Biden was calm and confident, although showed his awareness of the issues needed to be improved in the American policies, as well as demonstrated his concern with education, taxes, combat troops, and other critical issues. However, when confronted by Kamala Harris on the previous praising comments Biden made about people initiating segregation, the speaker failed to provide constructive reaction. He did not show composure but instead tried to justify his earlier statements without clearly responding to the questions asked.

Implications for Performance Improvement

Overall, as an experienced speaker, Biden showed a high level of competence in public speaking. However, such a type of performance as debates presents an opportunity not only to deliver the prepared information but also improvise when responding to unpredicted requests. Therefore, it is essential to remain calm and exude confidence driven by the goal of speech which, in this case, is persuasion of the voters to support the candidate in the elections.

Are Women Less Privileged In Society Than Men?

Gender relations that are observed in the western world have transformed significantly during recent decades. Certain political, economic, and social changes, as well as historical events, have caused critical alterations in gender roles while making male domination less typical of the society in developed countries. While women remain to be less privileged in some aspects of today’s society than men, in general, their social position seems to have improved over the past years.

Decades ago, the unprivileged position of women was determined by particular ideological and religious views that were accepted in society regarding females’ roles. As a result, in most cases, women were deprived of opportunities to participate in social activities, and they were expected to focus on duties mainly related to households. Gender inequality and the associated social stratification were typical of past societies (McGinn and Oh 85). Nowadays, the situation has changed significantly leading to transforming women’s roles and their impact on the social order.

Modern women and men have equal legal rights regarding their education, employment, and participation in social life. Currently, women can receive any education they want and occupy well-paid job positions (McGinn and Oh 84). This is mainly because gender discrimination in education and employment is currently illegal in most developed countries. As a result, the contribution of men and women to modern society is comparable, and women face less obstacles in their academic and professional careers.

These days, women seem to live in a context different from the past times, and they have access not only to education and employment but also to political power. The number of female politicians and influential social figures increases each year, illustrating the development of women’s role in society. The domination and authority of males cannot be viewed as the key feature of western society in a contemporary context (McGinn and Oh 86). Therefore, the overall role of women in political, economic, and social spheres of developed countries is strong, as they have the right to choose what responsibilities to take without reference to their gender.

Nevertheless, while positive trends in these areas show that the role of women has changed significantly over the past decades, there are still many gaps that affect women’s position in society. First of all, while employment discrimination is illegal in developed countries, there are still many cases where women are denied opportunities based on their gender. This phenomenon is called the glass ceiling, and it means that there is a certain limit to what a woman can achieve in her career. According to McGinn and Oh, women still face difficulties when trying to earn promotions to positions that entail significant decision-making and leadership capacities (86). Men, on the contrary, experience no gender-related obstacles and can move up the corporate ladder much more quickly.

Additionally, despite anti-discriminatory regulations, there is still a significant gender wage gap in many companies. A study by O’Reilly et al. showed that the gender pay gap in the United States was around 16% in 2013 (306). This means that for every $1 earned by a man, his female counterpart in the same position would earn 0.84 cents. The pay gap has a negative effect on women’s financial independence and shows that in contemporary workplaces, women still have an underprivileged position.

Another factor that influences women’s career success is their gender role. Although it has become much less restrictive due to feminism and anti-discriminatory legislation, women are still expected to take care of children most of the time, regardless of whether or not their partner actively participates in raising children. Research shows that 15 years after the family has the first child, women earn on average 32% less than their male partners (Angelov et al. 545). This means that women’s career development is often interrupted by pregnancy, maternal leave, and other similar circumstances (Graf et al.). Men have more freedom to focus on their career even if they are married and have children, and thus, they are in a more advantageous position compared to women.

In addition to the difficulties in employment discussed above, women are also at a higher risk of experiencing sexual harassment in the workplace. According to Quick and McFayden, the most prominent form of sexual harassment is when it is perpetrated by men against women, and in some workplaces, the risk for women is three to five times higher (287). Hence, women are much more likely than men to become victims of sexual harassment in the workplace and experience its damaging effects. Sexual harassment may cause women to quit their job or lose promotion opportunities, thus contributing to the burden of employment issues faced by women.

However, the high risk of sexual harassment of women is not limited to workplaces. In general, women experience sexual harassment and sexual assault at a higher rate than men. The difference is particularly high in developing countries, most of which still have a strong patriarchal order of society. In these settings, sexual violence against women is normalized, and most women face it at some point in their lives. In developed nations, the figures are still high, showing that women are at a disadvantage when it comes to sexual crimes.

A recent survey of college students found that 41.1% of women faced some form of sexual harassment since age 14, and 11% of those experienced rape (Jordan et al. 195). Sexual harassment and assault have an adverse impact on the victims’ emotional and psychological state and often lead to mental health issues, such as depression (Jordan et al. 192-193). The higher incidence of sexual assault victimization among women shows that they are less privileged than men in this area.

Finally, one of the most significant issue in women’s rights today is intimate partner violence (IPV). Most people already know that women become victims of domestic violence more often than men. Data from national studies indicate that there are significant differences in the prevalence of intimate partner violence among women and men. For instance, Brieding et al. found that severe physical violence by an intimate partner was reported by 24.3% of women, compared to 13.8% of men (15). While both figures are relatively high, it is evident that women become the victims of intimate partner violence more often than men, and thus, men are typically more privileged in this regard, too.

All in all, it is possible to conclude that the position of women in society has improved over the last decades. There are certain changes in cultural and social norms that have influenced women’s responsibilities and the idea of gender equality in general. As a result, contemporary women have more legal rights and opportunities to realize their potential and develop a successful career. Nevertheless, there are still some gaps that impact women’s social position, such as the gender pay gap, sexual and physical violence, and the glass ceiling. These problems are faced by women much more often than by men, and thus women remain less privileged despite all social and legal developments.

Work Cited

Angelov, Nikolay, et al. “Parenthood and the Gender Gap in Pay.” Journal of Labor Economics, vol. 34, no. 3, 2016, pp. 545-579.

Breiding, Matthew Joseph, et al. Intimate Partner Violence in the United States–2010. Centers for Disease Control and Prevention, 2014.

Jordan, Carol E., et al. ” An Exploration of Sexual Victimization and Academic Performance Among College Women.” Trauma, Violence, & Abuse, vol. 15, no. 3, 2014, pp. 191-200.

O’Reilly, Jacqueline, et al. ” Equal Pay as a Moving Target: International Perspectives on Forty-Years of Addressing the Gender Pay Gap.” Cambridge Journal of Economics, vol. 39, no. 2, 2015, pp. 299-317.

McGinn, Kathleen L., and Eunsil Oh. “Gender, Social Class, and Women’s Employment.” Current Opinion in Psychology, vol. 18, 2017, pp. 84-88.

Quick, James Campbell, and M. McFadyen. “Sexual Harassment: Have We Made Any Progress?” Journal of Occupational Health Psychology, vol. 22, no. 3, 2017, pp. 286-298.