Hormone: Definition and Its Type

Definition:

Hormone is a chemical substance secreted directly in to the body fluid by a cell or a group of cells or glands which exerts physiological controlling function on other cells or organ of the body.

Chemistry of hormone:

Chemically hormones are three types –

1. Steroid hormone:

a. Adrenal cortex hormone e.g. cortisol, Aldosterone.

b. Hormone of ovaries e.g. Estrogen, Progesterone.

c. Hormone of testes e.g. Testosterone.

2. Derivatives of amino acid tyrosine:

a. Thyroid gland hormone e.g. Thyroxin (T₄), Tri-iodothyronin (T₃).

b. Adrenal medullary hormone e.g. Adrenalin, nor adrenalin, dopamine

3. Protein or polypeptide hormones:

a. Posterior pituitary hormone / small polypeptide hormone. e.g. ADH (number of amino acid is 8), Oxytocin.

b. Large polypeptide hormone (number of amino acid is >10); e.g. Insulin, Glucagon, Parathormone.

c. Most hypothalamic hormone

d. Hormones of anterior pituitary – LH, GH etc.

Diabetes Mellitus: Definition and Classification

In this post I am gonna discuss about Diabetes mellitus.

Diabetes Mellitus:

It is a chronic metabolic disorder characterized by a high blood glucose concentration (hyperglycemia) and disturbances of carbohydrate, fat and protein metabolism caused by deficiency of insulin in the body or resistance to the action of insulin.

• DM affects about 5-8% of population
• In DM fasting plasma glucose > 7.0mmol/L
• DM is confirmed by GTT

Symptoms:

3P

• Polyphagia
• Polydypsia
• Polyuria

Treatment:

3D

• Discipline
• Diet
• Drugs

Complication of uncontrolled DM:

I. Micro vascular:

§  Retinopathy

§  Nephropathy

§  Neuropathy

§  Cataract

II. Macro vascular: Atherosclerosis following dyslipidemia leading to IHD and CVA

When the renal threshold for glucose reabsorption is exceeded, glucose come into urine (glycosuria), causes osmotic diuresis ( polyuria), which in turn result in dehydration, thirst and increased dinking tendency ( polydypsia) 

Types of Diabetes Mellitus:

1. IDDM (Type -1) Insulin dependent diabetes mellitus: It is severe form of diabetes mellitus, it occurs in juvenile period i.e. child & younger. Here, circulating insulin is virtually absent because β cell are damaged & β cell failed to secrete enzyme.

Criteria:

• Autoimmune type is commoner than idiopathic type
• Age <30yrs
• Abrupt onset
• Not obese when they first develop symptom
• Polyuria, polydipsia, polyphagia
• Due to absolute deficiency of insulin resulting form autoimmune destruction of beta cell
• Treatment – diet control and insulin
• Without insulin the treatment of such patient will die ultimately with diabetic ketoacidosis
• Diabetic ketoacidosis only occur in type I

2. NIDDM (Type-2) or maturity onset DM: It is milder form of diabetes, it occurs in adult. Here circulating insulin level is present but insufficient to reduce blood sugar level.

Criteria:

• Have genetic predisposition – about 90-95% sufferer have family history
• Age > 40
• Gradual onset
• Usually obese
• Usually asymptomatic
• Due to both by insulin resistance and impaired insulin secretion
• Treatment:

o    Initially diet control alone

o    Diet control + oral hypoglycemic drug

o    1/3^rd patient require insulin

§  Ketoacidosis is usually absent

3.  Type – 3 mellitus:

i. Drugs –

§  Corticosteroids

§  Thiazide diuretics

§  Phenytoin

ii. Some non pancreatic disease –

§  Acromegaly

§  Cushing’s syndrome

§  Pheocromocytoma

§  Hyperthyroidism

4. Type 4 DM:

• It is known as gestational diabetes (GDM)

GDM is defined as any abnormality in glucose level for the 1^st time during pregnancy

HIV : New Hope to Cure!

The discoverer of HIV (Human Immunodeficiency Virus) Nobel Winner Françoise Barré-Sinoussi  is hopeful to find a way to cure AIDS very soon.

More than 30 million of people died of AIDS since HIV was discovered in 1980. Till now there is no effective remedy for this virus.

Professor Francoise Barre Sinoussi said to BBC "We are so hopeful to discover the vaccine for HIV cause we have a lot of evidences in our hand.

Scientists was hapless a few days ago with discovery of HIV vaccine. But recent intervention of two HIV patients keeps the hope alive to discover the HIV vaccine.

European scientists are saying that an HIV patient is cured by Bone transplantation. Another 50 years old HIV  patient is said to be cured by Gene therapy without any other drugs. And these two incidence keep the hope alive.

Here to mention that, French virologist Professor Francoise Barre Sinoussi had been keep trying to discover the remedy to HIV after she discoverd HIV in 1980.

She won Nobel Prize with her colleague Luke Montegnier in 2008 for discovery of HIV.