Imagine this. A young teenager, 17, years old, who is fully developed. Now imagine this, the same teenager has a fully developed extra set of limbs and a pelvis. That extra set of pair is attached with chest artery. But, how can this happen?

While it is extremely rare, and has a chance of less than one case occurring per 100,000 births. Such things do happen. This is called parasitic twin.

What Is A Parasitic Twin?

It is an extremely rare type of cojoined twin where a baby is born with an underdeveloped twin attached to its body. This condition is also known as vestigial twins. The condition is very closely related to conjoined twins, where babies are connected at birth and share organs. However, the main difference is that in conjoined twins, there are two developed babies, whereas in parasitic twins, only one is fully developed, other one is underdeveloped and non functional.

In such a case, the twin who is developed is medically known as the autositic or the dominant twin. The dominant twin is healthy in most aspect but may have extra tissue, organs, or limbs from the parasitic twin.

The parasitic twin may be attached with the dominant twin through several places. The common joints are at the head, torso, chest, pelvis, buttocks, or back. In these cases, the parasitic twin is not alive and they die either in the womb or during the childbirth.

Doctors Remove Parasitic Twin

Now, let's go back to the case we referred to, where a young teenager had an extra pair of limbs attached to chest. The teenager who has not been named is from Uttar Pradesh's Unnao neighbourhood, and was treated in AIIMS, Delhi. The team of doctors successfully removed the extra set of limbs from his body.

Dr Asuri Krishna, who led the team of specialist who surgically removed the extra limbs told the BBC that only 40 to 50 cases of parasitic twins have been documented in world medical literature, and in those cases, the surgery had been attempted on children. The doctor said that without much medical literature to guide them, the team of doctors depended on "intuition, skill and knowledge".

The doctor shared that the child had two fully formed legs, buttocks and external genitalia, which weighed around 15kg "protruding from his abdomen".

How Was The Surgery Performed?

The doctor shared that first they identified how interconnected the parasitic and host twins were. The doctors took scans and found that parasitic twin was attached to the teen's breastbone. The blood was being supplied from a vessel in his chest. However, "there wasn't much connection with other main organs like the liver or kidneys," said Dr Krishna. The team also found a large cyst in the teen's abdomen.

Then the surgery was performed in two stages. In the first stage, the parasitic twin was removed. Then the cystic mass was extracted from the surrounded area. The entire surgery was completed in two and a half hours and the team of doctors included radiologists, anaesthetists, and plastic surgeons.

The biggest challenge was when the teen's blood pressure dropped as 30 to 40% of his blood flowed to the parasitic twin, however, the doctors were prepared for it and they stabilized him.

Adolescents who use cannabis could face a significantly higher risk of developing psychotic (doubled), bipolar (doubled), depressive and anxiety disorders, a study shows.

Researchers from Kaiser Permanente, the Public Health Institute's Getting it Right from the Start, the University of California, San Francisco and the University of Southern California, who studied 463,396 adolescents ages 13 to 17 through age 26, found that children between these ages were extremely prone to developing mental illnesses.

Lynn Silver, MD, program director of the Getting it Right from the Start, a program of the Public Health Institute, and study co-author noted: "As cannabis becomes more potent and aggressively marketed, this study indicates that adolescent cannabis use is associated with double the risk of incident psychotic and bipolar disorders, two of the most serious mental health conditions.

"The evidence increasingly points to the need for an urgent public health response - one that reduces product potency, prioritizes prevention, limits youth exposure and marketing and treats adolescent cannabis use as a serious health issue, not a benign behavior."

"Even after accounting for prior mental health conditions and other substance use, adolescents who reported cannabis use had a substantially higher risk of developing psychiatric disorders - particularly psychotic and bipolar disorders.

"This study adds to the growing body of evidence that cannabis use during adolescence could have potentially detrimental, long-term health effects. It's imperative that parents and their children have accurate, trusted, and evidence-based information about the risks of adolescent cannabis use," Kelly Young-Wolff, Ph.D., lead author of the study and senior research scientist at the Kaiser Permanente Division of Research, added.

The observational US-focused study also found that cannabis use was more common among adolescents enrolled in Medicaid and those living in more socioeconomically deprived neighborhoods.

How Does Cannabis Usage In Teens Affect Overall Health?

Strong links have also been found between adolescent cannabis use and mental health issues, including increased risk of depression, anxiety, and, in some cases, schizophrenia or other psychotic disorders.

Additionally, smoking cannabis can lead to breathing problems similar to tobacco, such as chronic bronchitis. It can also cause an increased heart rate, and some studies suggest a higher risk of heart attacks.

Early initiation, especially before age 16, increases the risk of developing Cannabis Use Disorder (addiction). High-potency products can lead to rapid onset of withdrawal symptoms, mood changes, and even physical complications like Cannabis Hyperemesis Syndrome (severe nausea/vomiting)

Why Should Early Cannabis Usage Be Discouraged?

Compared to teens who don't use cannabis, those who do are more likely to drop out of high school or not finish a college degree. Using cannabis can cause several immediate and long-term problems for teens:

• Difficulty Thinking
• Memory Issues
• Poor Coordination
• Attention Problems
• School and Social Troubles
• Cannabis use can also lead to more serious issues that affect a teen's overall life.
• Increased Mental Health Risks

Driving under the influence of cannabis is illegal and unsafe, as it severely slows reaction time. Cannabis reduces coordination and concentration, impacting all the skills necessary for responsible and safe driving.

Around 30 percent of cannabis users are also known to develop an addiction (cannabis use disorder). Failing to quit or choosing the drug over family activities are signs. This risk is higher for frequent teen users.

Scientists have created a three-dimensional "heart-on-a-chip" (HOC) model that beats on its own, uses calcium to initiate muscular activity and responds predictably to common drugs in hopes that it will help fight against cardiovascular diseases and heart failure.

This engineered heart is the first to incorporate a dual-sensing platform that provides real-time tracking of activity throughout the heart tissue down to the cellular level, helping scientists measure cellular function, which is critical for preventing heart failure in patients with CVDs.

First author Ali Mousavi, a biomedical engineer at the University of Montreal: "The ability to observe the tissue's response to different compounds in real time represents a major advantage for preclinical development and translational research."

To create their heart-on-chip (HOC) models, researchers collected heart muscle and connective tissue cells from rats. They placed the cells in a gel rich in proteins and nutrients to help them grow, then put them onto tiny, flexible silicon chips.

To measure how the tissue worked, they used two types of sensors. First, they attached the engineered heart tissue between two small elastic pillars. Each time the tissue beat, the pillars bent slightly, and this bending showed how strong the heartbeat was.

Then they placed tiny, soft gel-based sensors inside the tissue. These very small droplets—about 50 micrometers wide—changed shape as the cells contracted. This allowed the researchers to measure mechanical stress at the level of individual cells.

Talking about this development, senior author Houman Savoji, a mechanical and biomedical engineer at the University of Montreal said: "This breakthrough brings us even closer to true precision health by giving us the ability to identify the most effective medication for each person before treatment is even administered."

The Rising Heart Attack Crisis

During a heart attack, a lack of blood flow causes the cells and tissue in the heart muscle to die, leading to irreversible damage that can result in serious complications like arrhythmias, heart failure, cardiogenic shock, or cardiac arrest.

It is one of the leading causes of death in the country. Four Indians experience a heart attack every minute, with one in four dying of the cause. Experts have also noticed a rising trend of nearly 50 percent of heart attack patients being under the age of 40, with half of all heart attacks in Indian men occurring under 50.

Coronary Artery Disease: The Silent KillerCoronary artery disease (CAD) is one of the most common illnesses that can cause a heart attack in people. It develops over years and has no clear signs and symptoms apart from a heart attack.

The illness begins due to a buildup of fats, cholesterol and other substances known as plaque in and on the artery walls.

Over time, this can cause narrowing or blockage of the coronary arteries and block the supply of oxygen-rich blood to the heart which can lead to chest pain (angina), shortness of breath and ultimately, heart attacks.

READ MORE: How This Chinese Medicine Can Improve Blood Flow In Angina Patients

Typically, those above the age of 45, having a biological family member with heart disease, lack of sleep, smoking, consuming saturated fats along with other autoimmune diseases such as lupus and rheumatoid arthritis, can increase the risk of developing CAD.

Nearly one in 10 Indian adults suffer from CAD and about two million people die from the disease annually. Apart from this, about 18 to 20 million American adults aged 20 and older are also affected about the disease.

How Much You Should Exercise To Prevent CAD?

Moreover, regular exercise can also reduce the risk of Type 2 diabetes, high blood pressure, dementia and Alzheimer’s as well as several types of cancer. It can also help improve sleep, cognition, including memory, attention and processing speed.

Dr Hayes recommends opting for a cardiac evaluation such as an electrocardiogram, or EKG; a stress test; a cardiac MRI or CT scan to generate images of your heart if you notice changes in your ability to exercise or cannot perform consistent levels of exercise.

Long-term exposure to tiny air pollution particles can significantly increase your risk of developing Alzheimer's disease-caused dementia.

Researchers from Emory University, US have found that constant exposure to PM2.5 can affect the brain more directly than scientists have assumed.

They noted: "Alzheimer's disease is the most common form of dementia and a growing public health challenge, especially in aging populations. Our findings suggest that PM2.5 exposure was associated with increased Alzheimer's disease risk, primarily through direct rather than comorbidity-mediated pathways."

The scientists also discovered that those who had suffered a stroke were at a slightly higher risk of developing Alzheimer's disease, suggesting that strokes may make the brain more vulnerable to air pollution.

"The observed effect modification by stroke may reflect an underlying biological vulnerability in cerebrovascular pathways. Stroke-related neurovascular damage can compromise the blood–brain barrier, facilitating the translocation of PM2.5 particles or their associated inflammatory mediators into the brain."

The observational study was released in PLOS Magazine.

When Does The Risk Increase?

A new IIT Delhi study suggests the air quality may be worse than what conventional surface monitoring stations capture.

During a post-winter-haze day in March 2021, the researchers measured the vertical distribution of fine particulate matter at 20-metre intervals from the surface up to 100 meters through drones.

At 100 meters, PM2.5 concentrations were around 160 micrograms per cubic meter which is about 60 percent higher than surface readings on the same days. They also found that humidity levels were also higher by 70 percent, which promoted the concentration of ammonium nitrate and chloride.

Additionally, the study found that PM2.5 levels increased sharply near the top of this shallow layer, leading to higher concentrations at around 100 metres.

Based on these observations, the researchers concluded that residents in 28–30-storey buildings may face higher exposure to pollutants and inorganic material than indicated by ground-based monitors.

They also noted that drone-mounted low-cost sensors are a much more effective tool for studying the lower atmospheric boundary layer to improve air quality monitoring, model evaluation and mitigation strategies in cities such as Delhi.

What Is Alzheimer’s Disease?Alzheimer's disease is one of the most common forms of dementia and mostly affects adults over the age of 65.

About 8.8 million Indians aged 60 and above are estimated to be living with Alzheimer's disease. Over seven million people in the US 65 and older live with the condition and over 100,00 die from it annually.

Alzheimer's disease is believed to be caused by the development of toxic amyloid and beta proteins in the brain, which can accumulate in the brain and damage cells responsible for memory.

Amyloid protein molecules stick together in brain cells, forming clumps called plaques. At the same time, tau proteins twist together in fiber-like strands called tangles. The plaques and tangles block the brain's neurons from sending electrical and chemical signals back and forth.

Over time, this disruption causes permanent damage in the brain that leads to Alzheimer's disease and dementia, causing patients to lose their ability to speak, care for themselves or even respond to the world around them.

While there is no clear cause of Alzheimer's disease, experts believe it can develop due to genetic mutations and lifestyle choices, such as physical inactivity, unhealthy diet and social isolation.

Early symptoms of Alzheimer's disease include forgetting recent events or conversations. Over time, Alzheimer's disease leads to serious memory loss and affects a person's ability to do everyday tasks.

There is no cure for this progressive brain disorder and in advanced stages, loss of brain function can cause dehydration, poor nutrition or infection. These complications can result in death.