Non-communicable disease
Encyclopedia
A non-communicable disease, or NCD, is a medical condition or disease
Disease
A disease is an abnormal condition affecting the body of an organism. It is often construed to be a medical condition associated with specific symptoms and signs. It may be caused by external factors, such as infectious disease, or it may be caused by internal dysfunctions, such as autoimmune...

 which is non-infectious. NCDs are diseases of long duration and generally slow progression. They include heart disease
Heart disease
Heart disease, cardiac disease or cardiopathy is an umbrella term for a variety of diseases affecting the heart. , it is the leading cause of death in the United States, England, Canada and Wales, accounting for 25.4% of the total deaths in the United States.-Types:-Coronary heart disease:Coronary...

, stroke
Stroke
A stroke, previously known medically as a cerebrovascular accident , is the rapidly developing loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischemia caused by blockage , or a hemorrhage...

, cancer
Cancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...

, asthma
Asthma
Asthma is the common chronic inflammatory disease of the airways characterized by variable and recurring symptoms, reversible airflow obstruction, and bronchospasm. Symptoms include wheezing, coughing, chest tightness, and shortness of breath...

, diabetes
Diabetes mellitus
Diabetes mellitus, often simply referred to as diabetes, is a group of metabolic diseases in which a person has high blood sugar, either because the body does not produce enough insulin, or because cells do not respond to the insulin that is produced...

, chronic kidney disease, osteoporosis
Osteoporosis
Osteoporosis is a disease of bones that leads to an increased risk of fracture. In osteoporosis the bone mineral density is reduced, bone microarchitecture is deteriorating, and the amount and variety of proteins in bone is altered...

, Alzheimer's disease
Alzheimer's disease
Alzheimer's disease also known in medical literature as Alzheimer disease is the most common form of dementia. There is no cure for the disease, which worsens as it progresses, and eventually leads to death...

, cataract
Cataract
A cataract is a clouding that develops in the crystalline lens of the eye or in its envelope, varying in degree from slight to complete opacity and obstructing the passage of light...

s, and more. While often referred to as "chronic diseases", NCDs are distinguished by their non-infectious cause. In contrast, some chronic diseases such as HIV/AIDS, while also lasting medical conditions, are caused by transmissible infection
Infection
An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...

s. They are similar in that they also require chronic care management
Chronic care management
Chronic care management encompasses the oversight and education activities conducted by health care professionals to help patients with chronic diseases and health conditions such as diabetes, high blood pressure, lupus, multiple sclerosis and sleep apnea learn to understand their condition and...

.

The World Health Organization
World Health Organization
The World Health Organization is a specialized agency of the United Nations that acts as a coordinating authority on international public health. Established on 7 April 1948, with headquarters in Geneva, Switzerland, the agency inherited the mandate and resources of its predecessor, the Health...

 (WHO) reports NCDs to be by far the leading cause of mortality
Death
Death is the permanent termination of the biological functions that sustain a living organism. Phenomena which commonly bring about death include old age, predation, malnutrition, disease, and accidents or trauma resulting in terminal injury....

 in the world, representing over 60% of all deaths. Out of the 35 million people who died from NCDs in 2005, half were under age 70 and half were women. Of the 57 million global deaths in 2008, 36 million were due to NCDs . That is approximately 63% of total deaths worldwide. Risk factor
Risk factor
In epidemiology, a risk factor is a variable associated with an increased risk of disease or infection. Sometimes, determinant is also used, being a variable associated with either increased or decreased risk.-Correlation vs causation:...

s such as a person's background, lifestyle and environment are known to increase the likelihood of certain NCDs. Every year, at least 5 million people die because of tobacco use and about 2.8 million die from being overweight. High cholesterol accounts for roughly 2.6 million deaths and 7.5 million die because of high blood pressure. By 2030, deaths due to chronic NCDs are expected to increase to 52 million per year while deaths caused by infectious diseases, maternal and perinatal conditions and nutritional deficiencies are expected to decline by 7 million per year during the same period.

Causes and risk factors

Risk factor
Risk factor
In epidemiology, a risk factor is a variable associated with an increased risk of disease or infection. Sometimes, determinant is also used, being a variable associated with either increased or decreased risk.-Correlation vs causation:...

s such as a person's background, lifestyle and environment are known to increase the likelihood of certain non-communicable diseases. They include age, sex, genetics
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....

, exposure to air pollution
Air pollution
Air pollution is the introduction of chemicals, particulate matter, or biological materials that cause harm or discomfort to humans or other living organisms, or cause damage to the natural environment or built environment, into the atmosphere....

, and behaviours such as smoking
Smoking
Smoking is a practice in which a substance, most commonly tobacco or cannabis, is burned and the smoke is tasted or inhaled. This is primarily practised as a route of administration for recreational drug use, as combustion releases the active substances in drugs such as nicotine and makes them...

, unhealthy diet
Healthy diet
A healthy diet is one that helps maintain or improve general health. It is important for lowering many chronic health risks, such as obesity, heart disease, diabetes, hypertension and cancer. A healthy diet involves consuming appropriate amounts of all essential nutrients and an adequate amount of...

 and physical inactivity
Sedentary lifestyle
Sedentary lifestyle is a medical term used to denote a type of lifestyle with no or irregular physical activity. A person who lives a sedentary lifestyle may colloquially be known as a couch potato. It is commonly found in both the developed and developing world...

 which can lead to hypertension
Hypertension
Hypertension or high blood pressure is a cardiac chronic medical condition in which the systemic arterial blood pressure is elevated. What that means is that the heart is having to work harder than it should to pump the blood around the body. Blood pressure involves two measurements, systolic and...

 and obesity
Obesity
Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health, leading to reduced life expectancy and/or increased health problems...

, in turn leading to increased risk of many NCDs. Most NCDs are considered preventable because they are caused by modifiable risk factors.

The WHO's World Health Report 2002
World Health Report
The World Health Report is a series of reports produced regularly by the World Health Organization . First published in 1995, the World Health Report is WHO's leading publication...

 identified five important risk factors for non-communicable disease in the top ten leading risks to health. These are raised blood pressure, raised cholesterol
Cholesterol
Cholesterol is a complex isoprenoid. Specifically, it is a waxy steroid of fat that is produced in the liver or intestines. It is used to produce hormones and cell membranes and is transported in the blood plasma of all mammals. It is an essential structural component of mammalian cell membranes...

, tobacco use, alcohol consumption, and overweight. Other factors associated with higher risk of NCDs include a person's economic and social conditions, also known as the "social determinants of health
Social determinants of health
Social determinants of health are the economic and social conditions under which people live which determine their health. They are "societal risk conditions", rather than individual risk factors that either increase or decrease the risk for a disease, for example for cardiovascular disease and...

."

It has been estimated that if the primary risk factors were eliminated, 80% of the cases of heart disease, stroke and type 2 diabetes and 40% of cancers could be prevented. Interventions targeting the main risk factors could have a significant impact on reducing the burden of disease worldwide. Efforts focused on better diet and increased physical activity have been shown to control the prevalence of NCDs.

Environmental diseases

NCDs include many environmental disease
Environmental disease
In epidemiology, environmental disease is disease caused by environmental factors that are not transmitted genetically or by infection. Apart from the true monogenic genetic disorders, environmental diseases may determine the development of disease in those genetically predisposed to a particular...

s, covering a broad category of avoidable and unavoidable human health
Health
Health is the level of functional or metabolic efficiency of a living being. In humans, it is the general condition of a person's mind, body and spirit, usually meaning to be free from illness, injury or pain...

 conditions caused by external factors, such as sunlight, food, pollution, and lifestyle choices. The diseases of affluence
Diseases of affluence
Diseases of affluence is a term sometimes given to selected diseases and other health conditions which are commonly thought to be a result of increasing wealth in a society...

 are non-infectious diseases with environmental causes. Examples include:
  • Many types of cardiovascular disease
    Cardiovascular disease
    Heart disease or cardiovascular disease are the class of diseases that involve the heart or blood vessels . While the term technically refers to any disease that affects the cardiovascular system , it is usually used to refer to those related to atherosclerosis...

     (CVD)
  • Chronic obstructive pulmonary disease
    Chronic obstructive pulmonary disease
    Chronic obstructive pulmonary disease , also known as chronic obstructive lung disease , chronic obstructive airway disease , chronic airflow limitation and chronic obstructive respiratory disease , is the co-occurrence of chronic bronchitis and emphysema, a pair of commonly co-existing diseases...

     (COPD) caused by smoking tobacco
  • Diabetes mellitus type 2
    Diabetes mellitus type 2
    Diabetes mellitus type 2formerly non-insulin-dependent diabetes mellitus or adult-onset diabetesis a metabolic disorder that is characterized by high blood glucose in the context of insulin resistance and relative insulin deficiency. Diabetes is often initially managed by increasing exercise and...

  • Lower back pain caused by too little exercise
  • Malnutrition
    Malnutrition
    Malnutrition is the condition that results from taking an unbalanced diet in which certain nutrients are lacking, in excess , or in the wrong proportions....

     caused by too little food, or eating the wrong kinds of food (e.g. scurvy
    Scurvy
    Scurvy is a disease resulting from a deficiency of vitamin C, which is required for the synthesis of collagen in humans. The chemical name for vitamin C, ascorbic acid, is derived from the Latin name of scurvy, scorbutus, which also provides the adjective scorbutic...

     from lack of Vitamin C
    Vitamin C
    Vitamin C or L-ascorbic acid or L-ascorbate is an essential nutrient for humans and certain other animal species. In living organisms ascorbate acts as an antioxidant by protecting the body against oxidative stress...

    )
  • Skin cancer
    Skin cancer
    Skin neoplasms are skin growths with differing causes and varying degrees of malignancy. The three most common malignant skin cancers are basal cell cancer, squamous cell cancer, and melanoma, each of which is named after the type of skin cell from which it arises...

     caused by radiation from the sun

Inherited diseases

Genetic disorders are caused by errors in genetic information that produce diseases in the affected people. These errors may include:
  • A change in the chromosome numbers, such as Down syndrome
    Down syndrome
    Down syndrome, or Down's syndrome, trisomy 21, is a chromosomal condition caused by the presence of all or part of an extra 21st chromosome. It is named after John Langdon Down, the British physician who described the syndrome in 1866. The condition was clinically described earlier in the 19th...

  • A defect in a single gene caused by mutation
  • A rearrangement of genetic information


Cystic fibrosis
Cystic fibrosis
Cystic fibrosis is a recessive genetic disease affecting most critically the lungs, and also the pancreas, liver, and intestine...

 is an example of an inherited disease that is caused by a mutation
Mutation
In molecular biology and genetics, mutations are changes in a genomic sequence: the DNA sequence of a cell's genome or the DNA or RNA sequence of a virus. They can be defined as sudden and spontaneous changes in the cell. Mutations are caused by radiation, viruses, transposons and mutagenic...

 on a gene. The faulty gene impairs the normal movement of sodium chloride
Sodium chloride
Sodium chloride, also known as salt, common salt, table salt or halite, is an inorganic compound with the formula NaCl. Sodium chloride is the salt most responsible for the salinity of the ocean and of the extracellular fluid of many multicellular organisms...

 in and out of cells, which causes the mucus-secreting organs to produce abnormally thick mucus. The gene is recessive, meaning that a person must have two copies of the faulty gene for them to develop the disease. Cystic fibrosis affects the respiratory, digestive and reproductive systems, as well as the sweat glands. The mucus secreted is very thick and blocks passageways in the lungs and digestive tracts. This mucus causes problems with breathing and with the digestion and absorption of nutrients.

NCDs and global health

Historically, many NCDs were associated with economic development and so-called "diseases of the rich
Diseases of affluence
Diseases of affluence is a term sometimes given to selected diseases and other health conditions which are commonly thought to be a result of increasing wealth in a society...

". However, today an estimated 80% of the four main types of NCDs - cardiovascular diseases, cancers, chronic respiratory diseases and diabetes - occur in low- and middle-income countries. The prevention and control of NCDs is becoming increasingly important on the global health
Global health
Global health is the health of populations in a global context and transcends the perspectives and concerns of individual nations. Health problems that transcend national borders or have a global political and economic impact, are often emphasized...

 agenda.

NCDs and the United Nations

The World Health Organization
World Health Organization
The World Health Organization is a specialized agency of the United Nations that acts as a coordinating authority on international public health. Established on 7 April 1948, with headquarters in Geneva, Switzerland, the agency inherited the mandate and resources of its predecessor, the Health...

 is the specialized agency of the United Nations
United Nations
The United Nations is an international organization whose stated aims are facilitating cooperation in international law, international security, economic development, social progress, human rights, and achievement of world peace...

 (UN) that acts as coordinating authority on international public health
Public health
Public health is "the science and art of preventing disease, prolonging life and promoting health through the organized efforts and informed choices of society, organizations, public and private, communities and individuals" . It is concerned with threats to health based on population health...

 issues, including NCDs. In May 2008, the 193 Member States of the WHO approved a six-year plan to address non-communicable diseases, especially the rapidly increasing burden in low- and middle-income countries. The plan calls for raising the priority given to NCDs in international development
International development
International development or global development is a concept that lacks a universally accepted definition, but it is most used in a holistic and multi-disciplinary context of human development — the development of greater quality of life for humans...

 work.

During the 64th session of the United Nations General Assembly
United Nations General Assembly
For two articles dealing with membership in the General Assembly, see:* General Assembly members* General Assembly observersThe United Nations General Assembly is one of the five principal organs of the United Nations and the only one in which all member nations have equal representation...

 in 2010, a resolution was passed to call for a high-level meeting of the General Assembly on the prevention and treatment NCDs with the participation of heads of state and government. The resolution also encouraged UN Member States to address the issue of non-communicable diseases at the 2010 Review Summit for the Millennium Development Goals
Millennium Development Goals
The Millennium Development Goals are eight international development goals that all 193 United Nations member states and at least 23 international organizations have agreed to achieve by the year 2015...

.

In September 2011, the UN is hosting its first General Assembly Special Summit on the issue of NCDs. Noting that NCDs are the cause of some 35 million deaths each year, the international community is being increasingly called to take important measures for the prevention and control of non-communicable diseases, and mitigate their impacts on the world population especially on women, who are usually the primary caregivers.

Global Non-communicable Disease Network

In order to better coordinate efforts around the globe, in 2009 the WHO announced the launch of the Global Non-communicable Disease Network (NCDnet). NCDnet will consist of leading health organizations and experts from around the world in order to fight against diseases such as cancer, cardiovascular disease, and diabetes. Ala Alwan, assistant director-general for Non-communicable Diseases and Mental Health at the WHO, said: "integrating the prevention of non-communicable diseases and injuries into the national and global development agendas is not only achievable but also a priority for developing countries."

NCD Alliance

The NCD Alliance is a global partnership founded in May 2009 by four international federations representing cardiovascular disease
Cardiovascular disease
Heart disease or cardiovascular disease are the class of diseases that involve the heart or blood vessels . While the term technically refers to any disease that affects the cardiovascular system , it is usually used to refer to those related to atherosclerosis...

, diabetes, cancer
Cancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...

, and chronic respiratory disease
Respiratory disease
Respiratory disease is a medical term that encompasses pathological conditions affecting the organs and tissues that make gas exchange possible in higher organisms, and includes conditions of the upper respiratory tract, trachea, bronchi, bronchioles, alveoli, pleura and pleural cavity, and the...

. The NCD Alliance brings together roughly 900 national member associations to fight non-communicable disease. Long term aims of the Alliance include:
  1. NCD/disease national plans for all
  2. A tobacco free world
  3. Improved lifestyles
  4. Strengthened health system
    Health system
    A health system can be defined as the structured and interrelated set of all actors and institutions contributing to health improvement. The health system boundaries could then be referred to the concept of health action, which is "any set of activities whose primary intent is to improve or...

    s
  5. Global access to affordable and good quality medicines and technologies
  6. Human rights
    Human rights
    Human rights are "commonly understood as inalienable fundamental rights to which a person is inherently entitled simply because she or he is a human being." Human rights are thus conceived as universal and egalitarian . These rights may exist as natural rights or as legal rights, in both national...

     for people with NCDs.

Economics of NCDs

Previously, chronic NCDs were considered a problem limited mostly to high income countries, while infectious diseases seemed to affect low income countries. The burden of disease attributed to NCDs has been estimated at 85% in industrialized nations, 70% in middle income nations, and nearly 50% in countries with the lowest national incomes. In 2008, chronic NCDs accounted for more than 60% (over 35 million) of the 57 million deaths worldwide. Given the global population distribution, almost 80% of deaths due to chronic NCDs worldwide now occur in low and middle income countries, while only 20% occur in higher income countries.

National economies are reportedly suffering significant losses because of premature deaths or inability to work resulting from heart disease, stroke and diabetes. For instance, China is expected to lose roughly $558 billion in national income between 2005 and 2015 due to early deaths. In 2005, heart disease, stroke and diabetes caused an estimated loss in international dollars of national income of 9 billion in India and 3 billion in Brazil.

Absenteeism and presenteeism

The burden of chronic NCDs including mental health
Mental health
Mental health describes either a level of cognitive or emotional well-being or an absence of a mental disorder. From perspectives of the discipline of positive psychology or holism mental health may include an individual's ability to enjoy life and procure a balance between life activities and...

 conditions is felt in workplaces around the world, notably due to elevated levels of absenteeism
Absenteeism
Absenteeism is a habitual pattern of absence from a duty or obligation. Traditionally, absenteeism has been viewed as an indicator of poor individual performance, as well as a breach of an implicit contract between employee and employer; it was seen as a management problem, and framed in economic...

, or absence from work because of illness, and presenteeism
Presenteeism
Presenteeism is the act of attending work while sick. A topic that is at times considered its opposite, absenteeism, has historically received extensive attention in the management sciences, but presenteeism has only recently found a place in the research literature...

, or productivity lost from staff coming to work and performing below normal standards due to poor health
Health
Health is the level of functional or metabolic efficiency of a living being. In humans, it is the general condition of a person's mind, body and spirit, usually meaning to be free from illness, injury or pain...

. For example, the United Kingdom experienced a loss of about 175 million days in 2006 to absence from illness among a working population of 37.7 million people. The estimated cost of absences due to illness was over 20 billion pounds in the same year. The cost due to presenteeism is likely even larger, although methods of analyzing the economic impacts of presenteeism are still being developed. Methods for analyzing the distinct workplace impacts of NCDs versus other types of health conditions are also still being developed.

Cancer

The vast majority of cancer risk factors are environmental or lifestyle-related, thus cancer is largely a preventable NCD. Greater than 30% of cancer is preventable via avoiding risk factors including: tobacco
Tobacco
Tobacco is an agricultural product processed from the leaves of plants in the genus Nicotiana. It can be consumed, used as a pesticide and, in the form of nicotine tartrate, used in some medicines...

, being overweight
Overweight
Overweight is generally defined as having more body fat than is optimally healthy. Being overweight is a common condition, especially where food supplies are plentiful and lifestyles are sedentary...

 or obesity
Obesity
Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health, leading to reduced life expectancy and/or increased health problems...

, low fruit and vegetable intake, physical inactivity, alcohol
Alcohol
In chemistry, an alcohol is an organic compound in which the hydroxy functional group is bound to a carbon atom. In particular, this carbon center should be saturated, having single bonds to three other atoms....

, sexually transmitted infections, and air pollution
Air pollution
Air pollution is the introduction of chemicals, particulate matter, or biological materials that cause harm or discomfort to humans or other living organisms, or cause damage to the natural environment or built environment, into the atmosphere....

.

Cardiovascular disease

The first studies on cardiovascular health were performed in 1949 by Jerry Morris using occupational health data and were published in 1958. The causes, prevention, and/or treatment of all forms of cardiovascular disease remain active fields of biomedical research
Biomedical research
Biomedical research , in general simply known as medical research, is the basic research, applied research, or translational research conducted to aid and support the body of knowledge in the field of medicine...

, with hundreds of scientific studies being published on a weekly basis. A trend has emerged, particularly in the early 2000s, in which numerous studies have revealed a link between fast food and an increase in heart disease. These studies include those conducted by the Ryan Mackey Memorial Research Institute, Harvard University and the Sydney Center for Cardiovascular Health. Many major fast food chains, particularly McDonald's, have protested the methods used in these studies and have responded with healthier menu options.

A fairly recent emphasis is on the link between low-grade inflammation
Inflammation
Inflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process...

 that hallmarks atherosclerosis and its possible interventions. C-reactive protein
C-reactive protein
C-reactive protein is a protein found in the blood, the levels of which rise in response to inflammation...

 (CRP) is an common inflammatory marker that has been found to be present in increased levels in patients at risk for cardiovascular disease. Also osteoprotegerin
Osteoprotegerin
Osteoprotegerin , also known as osteoclastogenesis inhibitory factor , or tumor necrosis factor receptor superfamily member 11B , is a protein that in humans is encoded by the TNFRSF11B gene...

 which involved with regulation of a key inflammatory transcription factor called NF-κB has been found to be a risk factor of cardiovascular disease and mortality.

Diabetes

Diabetes mellitus is an NCD which is largely preventable and manageable but difficult to cure. Management concentrates on keeping blood sugar levels as close to normal ("euglycemia") as possible without presenting undue patient
Patient
A patient is any recipient of healthcare services. The patient is most often ill or injured and in need of treatment by a physician, advanced practice registered nurse, veterinarian, or other health care provider....

 danger. This can usually be with close dietary management, exercise, and use of appropriate medications (insulin only in the case of type 1 diabetes mellitus. Oral medications may be used in the case of type 2 diabetes, as well as insulin).

Patient education, understanding, and participation is vital since the complications of diabetes are far less common and less severe in people who have well-managed blood sugar levels.
Wider health problems may accelerate the deleterious effects of diabetes. These include smoking
Tobacco smoking
Tobacco smoking is the practice where tobacco is burned and the resulting smoke is inhaled. The practice may have begun as early as 5000–3000 BCE. Tobacco was introduced to Eurasia in the late 16th century where it followed common trade routes...

, elevated cholesterol
Hypercholesterolemia
Hypercholesterolemia is the presence of high levels of cholesterol in the blood. It is not a disease but a metabolic derangement that can be caused by many diseases, notably cardiovascular disease...

 levels, obesity
Obesity
Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health, leading to reduced life expectancy and/or increased health problems...

, high blood pressure
Hypertension
Hypertension or high blood pressure is a cardiac chronic medical condition in which the systemic arterial blood pressure is elevated. What that means is that the heart is having to work harder than it should to pump the blood around the body. Blood pressure involves two measurements, systolic and...

, and lack of regular exercise.

Chronic kidney disease

Although chronic kidney disease (CKD) is not currently identified as one of WHO's main targets for global NCD control, there is compelling evidence that CKD is not only common, harmful and treatable but also a major contributing factor to the incidence and outcomes of at least three of the diseases targeted by WHO (diabetes, hypertension and CVD).
CKD strongly predisposes to hypertension and CVD; diabetes, hypertension and CVD are all major causes of CKD; and major risk factors for diabetes, hypertension and CVD (such as obesity and smoking) also cause or exacerbate CKD. In addition, among people with diabetes, hypertension, or CVD, the subset who also have CKD are at highest risk of adverse outcomes and high health care costs. Thus, CKD, diabetes and cardiovascular disease are closely associated conditions that often coexist; share common risk factors and treatments; and would benefit from a coordinated global approach to prevention and control.

See also

  • Chronic disease
  • Non-infectious disease
  • Global health
    Global health
    Global health is the health of populations in a global context and transcends the perspectives and concerns of individual nations. Health problems that transcend national borders or have a global political and economic impact, are often emphasized...

  • The INCTR Challenge Fund project of the International Network for Cancer Treatment and Research

External links

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