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Competitive, uncompetitive and non competitive enzyme inhibitors

(A) Enzyme–substrate complex;  (B) a competitive inhibitor binds at the active site and thus prevents the substrate from binding;  (C) an uncompetitive inhibitor binds only to the enzyme–substrate complex;  (D) a noncompetitive inhibitor does not prevent the substrate from binding.

Visceral and parietal layer of serous pericardium

Pericardium The pericardium is a fibroserous sac surrounding the heart and the roots of the great vessels. It consists of two components,  1) the fibrous pericardium and  2) the serous pericardium. The fibrous pericardium is a tough connective tissue outer layer that defines the boundaries of the middle mediastinum.  The serous pericardium is thin and consists of two parts: 1) The parietal layer lines the inner surface of the fibrous. 2) The visceral layer adheres to the heart and forms its outer covering. The parietal and visceral layers of serous pericardium are continuous at the roots of the great vessels. The narrow space created between the two layers of serous pericardium, containing a small amount of fluid, is the pericardial cavity. This is pictured in the diagram above as a fist in a filled balloon. This potential space allows for the relatively uninhibited movement of the heart. Fibrous pericardium The fibrous pericardium is a cone-shape

Diaxozide - mechanism of action

The diagram shows a beta cell of the islet of pancreas and will explain how local factors regulate secretion of insulin from it. Glucose enters the cell via the GLUT-2 transporter. Inside the cell there is metabolism with the generation of ATP. This causes the ATP-sensitive K+ channel to close, as shown in A. Closure of this channel leads to cell membrane depolarization. This in turn allows calcium ions to enter the cell via another calcium channel, shown in B. Increased intracellular calcium activates calcium dependent phospholipid protein kinase. This leads to exocytosis of insulin granules. Diaxozide acts by opening the K+ channel. This leads to loss of K+ and causing membrane hyperpolarization. This prevents Ca2+ from entering, protein kinases are not activated and thus there is no exocytosis of insulin granules... 

Prognostic scores in alcoholic hepatitis

1. Maddrey (modified) Discriminant Function score of greater or equal to 32 indicates a high risk (30-50%) risk of mortality at 30 days. The risk is even higher is there are signs of hepatic encephalopathy. Scores should be repeated at day 7. 2. MELD stands for Model for End stage Liver Disease. It is used to estimate 90 days mortality. Poor prognosis if score is greater than 18. Score should be repeated at day 7.

Effect of weather on COPD

Exacerbations of COPD are more commonly seen during the winter season (nearly 1.6 times more frequently). The main cause of these exacerbations is infection with the respiratory virus, rhinovirus. Frequent exacerbations have been shown to lead to a faster decline in the lung function, poorer quality of life and increased mortality. A recent study showed that COPD exacerbations in colder periods of the year take longer to recover from and are more likely to involve cough or coryzal symptoms. The exacerbations in the cold seasons also have a greater impact on daily activity, with patients spending more time indoors and being more likely to be hospitalized with respiratory viral infection.