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Topic Review
Tuskegee Syphilis Experiment
The Tuskegee Study of Untreated Syphilis in the African American Male was a clinical study conducted between 1932 and 1972 by the United States Public Health Service. The purpose of this study was to observe the natural history of untreated syphilis; the African-American men in the study were only told they were receiving free health care from the Federal government of the United States. The Public Health Service started the study in 1932 in collaboration with Tuskegee University (then the Tuskegee Institute), a historically black college in Alabama. Investigators enrolled in the study a total of 600 impoverished, African-American sharecroppers from Macon County, Alabama. Of these men, 399 had latent syphilis, with a control group of 201 men who were not infected. As an incentive for participation in the study, the men were promised free medical care, but were deceived by the PHS, who disguised placebos, ineffective methods, and diagnostic procedures as treatment. The men who had syphilis were never informed of their diagnosis, despite the risk of infecting others, and the fact that the disease could lead to blindness, deafness, mental illness, heart disease, bone deterioration, collapse of the central nervous system, and death.. According to the Centers for Disease Control and Prevention, the men were told that they were being treated for "bad blood,” a colloquialism that described various conditions such as syphilis, anemia and fatigue. "Bad blood"—specifically the collection of illnesses the term included—was a leading cause of death within the southern African-American community. The men were initially told that the study was only going to last six months, but it was extended to 40 years. After funding for treatment was lost, the study was continued without informing the men that they would never be treated. None of the infected men were treated with penicillin despite the fact that by 1947, the antibiotic had become the standard treatment for syphilis. Study clinicians could have chosen to treat all syphilitic subjects and close the study, or split off a control group for testing with penicillin. Instead, they continued the study without treating any participants; they withheld treatment and information about it from the subjects. In addition, scientists prevented participants from accessing syphilis treatment programs available to other residents in the area. The study continued, under numerous Public Health Service supervisors, until 1972, when a leak to the press resulted in its termination on November 16 of that year. The victims of the study, all African-American, included numerous men who died of syphilis, 40 wives who contracted the disease and 19 children born with congenital syphilis. The 40-year Tuskegee Study of Untreated Syphilis in the African American Male study was a major violation of ethical standards. Researchers knowingly failed to treat participants appropriately after penicillin was proven to be an effective treatment for syphilis and became widely available. Moreover, participants remained ignorant of the study clinicians’ true purpose, which was to observe the natural course of untreated syphilis. The revelation in 1972 of study failures by a whistleblower, Peter Buxtun, led to major changes in U.S. law and regulation concerning the protection of participants in clinical studies. Now studies require informed consent, communication of diagnosis and accurate reporting of test results. The Tuskegee Syphilis Study, cited as "arguably the most infamous biomedical research study in U.S. history," led to the 1979 Belmont Report and to the establishment of the Office for Human Research Protections (OHRP). It also led to federal laws and regulations requiring institutional review boards for the protection of human subjects in studies involving them. The OHRP manages this responsibility within the United States Department of Health and Human Services (HHS). On May 16, 1997, President Bill Clinton formally apologized on behalf of the United States to victims of the study.
  • 1.8K
  • 07 Nov 2022
Topic Review
Ceramic Materials for Biomedical Applications
The word “biomaterial” refers to a substance or a mix of materials of synthetic or natural origin interacting with biological systems. The main purpose of biomaterials is to support the healing or replacement of an organ in a human body that has been altered by a disease or an accidental event and to successfully restore function and sometimes aesthetic features without endangering human life. Biomaterials can be classified according to their chemical nature as metallic, polymeric, ceramic, and composite, and can also be biologically derived. The term “ceramic” (from the Greek word κεραμικό: “keramikò,” which means “burnt stuff”), a word that is also found in ancient texts, indicates any heat-treated material derived from clayey raw materials through a process called firing. Generally speaking, ceramics are inorganic materials consisting of metallic and non-metallic components chemically bonded together by means of ionic or prevalently ionic bonds with a variable degree of covalent character. 
  • 1.8K
  • 07 Apr 2023
Topic Review
1,2,4-Triazoles
Compounds containing the 1,2,4-triazole ring in their structure are characterised by multidirectional biological activity.
  • 1.8K
  • 23 Aug 2021
Topic Review
Polyurethanes in Biomedicine
Due to their mechanical properties, ranging from flexible to hard materials, polyurethanes (PUs) have been widely used in many industrial and biomedical applications. PU characteristics, along with their biocompatibility, make them successful biomaterials in short and medium time applications.  The most important biomedical applications of PUs include antibacterial surfaces and catheters, blood oxygenators, dialysis devices, stents, cardiac valves, vascular prostheses, bioadhesives/surgical dressings/pressure sensitive adhesives, drug delivery systems, tissue engineering scaffolds and electrospinning, nerve generation, pacemaker lead insulation and coatings for breast implants. The diversity of polyurethane properties due to the ease of bulk and surface modification plays a vital role in their applications. 
  • 1.8K
  • 28 Oct 2020
Topic Review
Chitosan-Nanoparticles for Oral Insulin Delivery
Diabetes mellitus is a chronic endocrine disease, affecting more than 400 million people around the world. Patients with poorly controlled blood glucose levels are liable to suffer from life-threatening complications, such as cardiovascular, neuropathy, retinopathy and even premature death. Today, subcutaneous parenteral is still the most common route for insulin therapy. Oral insulin administration is favourable and convenient to the patients. In contrast to injection route, oral insulin delivery mimics the physiological pathway of endogenous insulin secretion. However, oral insulin has poor bioavailability (less than 2%) due to the harsh physiological environment through the gastrointestinal tract (GIT). Over the last few decades, many attempts have been made to achieve an effective oral insulin formulation with high bioavailability using insulin encapsulation into nanoparticles as advanced technology. Various natural polymers have been employed to fabricate nanoparticles as a delivery vehicle for insulin oral administration. Chitosan, a natural polymer, is extensively studied due to the attractive properties, such as biodegradability, biocompatibility, bioactivity, nontoxicity and polycationic nature. Numerous studies were conducted to evaluate chitosan and chitosan derivatives-based nanoparticles capabilities for oral insulin delivery. This review highlights strategies that have been applied in the recent five years to fabricate chitosan/chitosan derivatives-based nanoparticles for oral insulin delivery. A summary of the barriers hurdle insulin absorption rendering its low bioavailability such as physical, chemical and enzymatic barriers are highlighted with an emphasis on the most common methods of chitosan nanoparticles preparation. Nanocarriers are able to improve the absorption of insulin through GIT, deliver insulin to the blood circulation and lower blood glucose levels. In spite of some drawbacks encountered in this technology, chitosan and chitosan derivatives-based nanoparticles are greatly promising entities for oral insulin delivery.
  • 1.8K
  • 02 Nov 2020
Topic Review
Fruit by-Products
Fruit by-Products deals with the bioactive compounds present in the by-products generated by the fruit processing industry with large amounts. These bioactive compounds are mainly dietary fibres, phenolic compounds, proteins and lipids. They have significant chemical, physical and biological properties which make fruits by-products a good source for new supplements in food products having important effect on intestinal function. 
  • 1.8K
  • 03 Dec 2020
Topic Review
Glass Ionomer Cement
The glass ionomer cement (GIC) is a translucent, water-based cement invented in 1972 by Wilson and Kent.
  • 1.8K
  • 30 Nov 2021
Topic Review
Body Image Disturbance
Body image disturbance (BID) is a common symptom in patients with eating disorders. The onset is mainly attributed to patients with anorexia nervosa who persistently tend to subjectively discern themselves as average or overweight despite adequate, clinical grounds for a classification of being severely underweight. The symptom is an altered perception of one's body and a severe state of bodily dissatisfaction characterizing the body image disturbance. It is included among the diagnostic criteria for anorexia nervosa in DSM-5 (criterion C). The disturbance is associated with significant bodily dissatisfaction and is a source of severe distress, often persisting even after seeking treatment for an eating disorder, and is regarded difficult to treat. Thus, effective body image interventions could improve the prognosis in patients with ED, as experts have suggested. Unfortunately, there is no hard evidence that current treatments for body image disturbance effectively reduce eating disorders' symptoms. Furthermore, pharmacotherapy is ineffective in reducing body misperception and it has been used to focus on correlated psychopathology (e.g., mood or anxiety disorders). However, to date, research and clinicians are developing new therapies as virtual reality experiences, mirror exposure or multisensory integration body techniques, which have shown some extent of efficacy.
  • 1.8K
  • 22 Nov 2022
Topic Review
Antibiotic Resistance
Antibiotics are defined as natural or synthetic chemicals inhibiting both the growth and survival of microorganisms. These compounds have been used as essential therapeutics for nearly a century. With the human population growth increasingly, antibiotics become preventive agents in the agricultural and animal industry. The multi-faceted global use and misuse of antibiotics led to the evolution of bacteria into antibiotic resistant species. Advantageous mutations cause antibiotic tolerance, which is transmitted to offspring (vertical evolution) or to another bacteria via conjugation, transduction, or transformation mode (horizontal evolution), that are then are then passed down to progeny (vertical evolution). Antibiotic resistance progressively increased mortality from multidrug-resistant bacterial infections, threatening public health. Probiotics, essential oils, vaccines, and antibodies to antibiotic resistant bacteria emerge as primary or adjunct preventive measures or therapies against multidrug-resistant bacterial infections. Bacteriophages and predatory bacteria, as well as utilization of bacterial communication quorum sensing considered as new ecosystem-influenced methods to tackle multidrug-resistant bacteria. Mechanisms of dissemination and the development of antibiotic resistance genes vary in the context of nutrition and related clinical, agricultural, veterinary, and environmental settings, this need to be accounted in selections of preventive and therapeutic countermeasures. 
  • 1.8K
  • 05 Feb 2022
Topic Review
Neonatal Early-Onset Sepsis
Neonatal early-onset sepsis (EOS) is defined as an invasive infection that occurs in the first 72 h of life. The incidence of EOS varies from 0.5–2 per 1000 live births in developed countries, up to 9.8 per 1000 live births in low resource settings, generating a high mortality rate, especially in extremely low birth weight neonates. Clinical signs are nonspecific, leading to a late diagnosis and high mortality. Currently, there are several markers used for sepsis evaluation, such as hematological indices, acute phase reactants, cytokines, which by themselves do not show acceptable sensitivity and specificity for the diagnosis of EOS in neonates. Newer and more selective markers have surfaced recently, such as presepsin and endocan, but they are currently only in the experimental research stages.
  • 1.8K
  • 28 Sep 2021
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