Collagen Defects

Collagen Defects

Meningitis

Most common cause of neonatal meningitis is:

G - GBS - number 1 cause

E - Ecoli - number 2 cause

L - Listeria - number 3 cause

If the child is 3-2 years age and not vaccinated - H. Influenza

If the child is 3 months - 2 years old - and vaccinated - Strep Pneumonae is the most common cause

More on Meningitis and USMLE Step 1 High Yield info - check out www.tutia.com.  You can find study partners as well.  

Pseudomonas

gram negative bacilli, oxidase +

blue-green

black necrotic centre, erythematous margin

ecthyma gangrenosum

Patient might have:

-hot tub folliculitis, eye problems

Burn patients - cellulitis and do not take raw vegetables or flowers to the burn unit or near burn patients.  

Please visit www.tutia.com.  You can find more tips on this website.  It is a social network site for medical students and doctors.  

Semester 1
The Developing Human: Clinically Oriented Embryology With STUDENT CONSULT Online Access
Atlas of Anatomy (Thieme Anatomy)
Atlas of Human Anatomy: with Student Consult Access (Netter Basic Science)
diFiore's Atlas of Histology with Functional Correlations (Point (Lippincott Williams & Wilkins))
Color Atlas of Histology
Users' Guides to the Medical Literature: A Manual for Evidence-Based Clinical Practice, Second Edition (Jama & Archives Journals)

Semester 2
Lippincott's Illustrated Reviews: Biochemistry (Lippincott's Illustrated Reviews Series)
Marks' Basic Medical Biochemistry: A Clinical Approach (Point (Lippincott Williams & Wilkins))
Medical Epidemiology (LANGE Basic Science)
Thompson & Thompson Genetics in Medicine: With STUDENT CONSULT Online Access
Textbook of Medical Physiology: With STUDENT CONSULT Online Access (Guyton Physiology)
Physiology: with STUDENT CONSULT Online Access (Costanzo Physiology)
Clinical Ethics: A Practical Approach to Ethical Decisions in Clinical Medicine, Seventh Edition (LANGE Clinical Science)

Semester 3
Kaplan and Sadock's Synopsis of Psychiatry: Behavioral Sciences/Clinical Psychiatry
Basic Immunology Updated Edition: Functions and Disorders of the Immune System With STUDENT CONSULT Online Access
Problem-Based Microbiology
Clinical Neuroanatomy
Neuroanatomy: An Atlas of Structures, Sections, and Systems (Neuroanatomy: An Atlas of Strutures, Sections, and Systems ()

Semester 4
Robbins & Cotran Pathologic Basis of Disease: With STUDENT CONSULT Online Access (Robbins Pathology)
Robbins Basic Pathology, Eighth EditionRobbins Basic Pathology, Eighth Edition
Lippincott's Illustrated Reviews: Pharmacology, 4th Edition (Lippincott's Illustrated Reviews Series)
Bates' Guide to Physical Examination and History Taking, 10th Edition
Medical Terminology: A Short Course










Semester 5








Kochar's Clinical Medicine for Students
First Aid for the USMLE Step 1 2011 (First Aid USMLE)

Search Amazon.com for stescopeLisle 52500 Mechanic's Stethoscope

Herniation of Nucleus Pulposus

Herniation of Nucleus Pulposus

Most common direction of herniation is posteriolateral

Attacking multiple choice questions

USMLE is based on multiple choice questions.  There are about 322 multiple choice questions.    So knowing how to approach them is one of the key to successfully passing USMLE Step 1.  These tips will help you while practicing review questions as well. 

·         Read the question carefully and form a mental picture.  

·         Remember the key words

·         Understand the question

·         Come up with an answer before looking at the answer choices.    Many of us make the mistake of scanning the answers first.  This will lead you into a pit. 

·         Analyze and compare the answer choice against your answer.  Mentally recall the question and link back to the question. 

·         Mark the best answer.  Always mark the best answer.  There could be more than once choice but pick the BEST answer. 

Pemphigus Vulgaris vs Bullous Pemphigoid

Pemphigus vulgaris
- desmosonal - autoantibodies
- painful blisters
- common places - oropharynx and skin

Bullous Pemphigoid
- hemidesmosomal - autoantibodies
- rare on oral mucosa
- blistering with pruritus
- can be drug induced

Maternally Inherited Mitochondrial Diseases

1) Leber's optic neuropathy
2) Pearson Marrow-Pancreas syndrom
3) Male infertility

How to study for USMLE Step 1

Getting a 99 on USMLE is possible.  The harder you work at it, it will reward you in big way.   People before us have done it and people after us are going to do it as well.  So here is the chance for you to shine.  You have sacrificed so much to come to this phase of life.   Give your best for this.  If you fail, you will suffer.  The score will hunt you for the rest of your medical career.  So here is your chance to give your very best for YOU!

Before you start studying for step 1, answer these questions.  Take few hours and think clearly.  I find that doing yoga helps me relax and set goals.  Take a seat at a clean desk.  Get a note pad and a pen.  Start answering these questions and be honest. 

• What is my goal at the end of this year?
• What is my goal at the end of next year?
• Who am I studying for?
• Do I want to make the best doctor and why?  
• What score do I want on USMLE Step 1?  
• How would I feel when I have achieved this?
• Are there anything preventing me from getting this score?  
• Do you have all the resources?  
• Make a schedule and write down daily routines. 
• Do I have a study buddy?  If not, how am I going to make sure that I am target?
• Am I giving my very best?

Make sure you write down your answers and look at them daily.  Writing the answers is the best way to get to your goal.  Don`t cheat yourself by orally answering them.   

Here is what you need to have it in your memory before the exam:

·         Kaplan books, videos, qbank

·         USMLE world

·        Kaplan Q book

·        First AID book and questions

·         High Yield Neuroanatomy

·         High Yield Pathology

·         High Yield Histology

·         Goljan Pathology – do the questions as well. 

Here is a simple study guide to follow.  Follow these steps and achieve your 99 on your USMLE step1.  I am average student but following a process helped me stay on target. 

2 weeks – Physiology

2 weeks – Anatomy (embryo as well)

2 weeks – Biochemistry

2 weeks – Pharmacology

2 weeks – Pathology

2 weeks – Microbiology, Behavioural sciences, Genetics

As you study along, do qbank, USMLE world, and any other question bank that you can find.  Take notes as you along.  There is nothing like your own notes.  Don`t take notes the first time you read something.  Take notes of things you can`t remember and review it again and again. 

Last 3 weeks do as stimulated questions (in blocks).  Mock the exam day.  Review the materials that you are having hard time remembering. 

Days before exam try to relax and mock the exam day.  Make snacks to keep you energized. 

2-3 days before the exam, review the First Aid and nothing else.  Tell yourself you can do this.  Do stimulated questions. 

Day before exam – have fun and relax.  Maybe watch your favourite movie.  Do some yoga or exercise. 

The morning of the day before the exam - Eat a healthy breakfast and relax your mind.  Picture yourself getting 99 and walking out of that exam room excited and satisfied. 

In the center – Just take deep breaths and tell yourself, you can do it. 

Do the first two block simultaneously.  Taking break after the first block is not recommended.  Take a break before you start the third block.  Stretch and eat a snack and drink lots of water.  Write something on the marker board to encourage you.  Do the next two blocks and take a break.  Don`t eat something heavy because it will make you sleepy.  Make sure you are energized.  Keep your mind stimulated by writing down positive things about you on the marker board.  Do the next two blocks and take break.  Do the last block and you are done!!!

Congratulate yourself and walk confidently out of that exam room. 



UMN lesion & LMN lesion

Upper Motor Neuron lesion - everything is increased in intensity (that is how i remember it)
- hyperreflexia
- increased muscle tone
- babinski sign
- spastic paresis
- disuse atrophy of muscles

Lower Motor Neuron - intensity is decreased
- areflexia
- decreased muscle tone
- atrophy of muscle
- loss of voluntary movements
- flaccid paralysis

Horner Syndrome

P - Ptosis - drooping of eyelids
A - anhidrosis - lack of sweat in face
M - miosis - pupillary constriction

Horner syndrome - occurs when there is lesion to the descending hypothalamic fibers - innervating preganglionic symp. neurons in T1 to T4

Here is some facts on TSH, FSH, LH

I hope your studying for step 1 is going well.  Do study the First Aid.  The First Aid Q & A is an excellent source of questions to do while studying. 

First Aid for the USMLE Step 1 2011 (First Aid USMLE)

First Aid Q&A for the USMLE Step 1, Second Edition (First Aid USMLE)

I recommend making a realistic schedule and sticking to it.  You know yourself better so time yourself.  Have fun studying.  If you need a good Physiology book, I recommend:

Physiology: with STUDENT CONSULT Online Access (Costanzo Physiology).  Excellent book! 

Here is some facts on TSH, FSH, LH

• Glycoproteins ( with sugar moieties covalently linked to asparagines)
• Each is made up of an alpha and beta subunits (not covalently linked)
• Alpha subunits of TSH, FSH, LH are identical (synthesized from the same mRNA)
• Pairing of alpha and beta – in the ER and continues in the Golgi
• HCG – structurally similar to TSH, FSH and LH. 
• Glycoprotein with same alpha chain. 

Pituitary Gland

• 2 fused glands (anterior and posterior)
• Extends down from the brain – connected by thin stalk

Anterior Pituitary Gland (adenohypophysis)

• Epithelial origin – embryonic tissue that formed the roof of the mouth
• 6 hormones – all controlled by hypothalamus
• Prolactin, TSH, ACTH, GH, FSH, LH
• A.p. hormones control growth, metabolism, and reproduction
• Prolactin – milk production
• GH (somatotropin)
• Metabolism of many tissues
• Activates hormone production by liver
• FSH, LH – gonadotrophins (ovaries and testes)
• TSH (thyrotropin) – controls hormone synthesis + secretion in the thyroid gland
• ACTH (corticotrophin) – acts on adrenal cortex à cortisol

Amine Hormones

·         Derived either from tryptophan (melatonin), tyrosine (all other amine hormones – catecholamine + thyroid hormones)

o   Catecholamine à have 1 tyrosine molecule

o   Thyroid hormones – 2 tyrosine molecules + iodine atoms (thyroid hormones behave more like steroid hormones)

Cellular Mechanism of Action of Steroid Hormones

·         Destination – to the nucleus.  Activates transcriptional factor à binds to DNA and either activating or inhibiting one or more genes. 

·         Activation of genes à create new mRNA à new protein (genomic effect on the target cells)

·         Exception: Estrogen and aldosterone à have cell membrane receptors linked to signal transduction pathways (like peptide hormones).  These receptors enable those hormones to initiate rapid non-genomic responses in addition to their slower genomic effect. 

Neural Reflexes

Neural Reflexes:

1.       Efferent division that controls the effector

a.       Somatic motor neurons control sk. Muscle

b.      Autonomic neurons control smooth and cardiac muscle, glands, and adipose tissue

2.       Integrating region within the central nervous system

a.       Spinal reflexes don’t require input from the brain

b.      Cranial reflexes are integrated within the brain

3.       Time at which the reflex develops

a.       Innate (inborn) reflexes are genetically determined

b.      Learned reflexes are acquitted through experience

4.       The number of neurons in the reflex loop

a.       Monosynaptic reflexes have only two neurons: sensory – afferent and one efferent.  Only somatic motor reflexes can be monosynaptic

b.      Polysynaptic reflexes – one or more interneurons between the afferent and the efferent neurons.  All autonomic reflexes are polysynaptic because they have three neurons: one afferent and two efferent. 

Endocrine: Steroid Hormones - some facts for Step 1

·         Derived from Cholesterol

·         They all have similar structures

·         Only made in few organs for example

o   Adrenal cortex

o   Gonads produce sex hormones

Steroid Hormone Synthesis and Release

·         Cells that secrete steroid hormones have abundant SER

·         SER – location of steroid synthesis

·         Lipophilic and therefore easily diffuse across the cell membrane

·         Synthesized as needed EXCEPT for thyroid hormones

Transport in the blood & half life of steroid hormones

·         Lipophilic – not soluble in plasma

·         Most steroid hormones are bound to protein carrier molecules

o   Some have specific carriers – corticosteroid binding globulin

o   Others simply bind to general plasma protein – ie: albumin

o   Exception – adrenal androgens – no carrier proteins      

·         Half life of steroids are much longer than that of peptide hormones

·         There is always and equilibrium between bound hormones and unbound hormones.  So the ratio between the two in the plasma is constant.  Carriers release the hormone and they then simply diffuse across the cell.

·         Unbound (free) hormones are available to tissues

·         Free form creates the negative feedback à regulated!

3 hormones that increase blood glucose level are:

- Epinephrine
- Glucagon
- Cortisol

USMLE Step 1 - Endocrine: peptide hormones

Hello all fellow students,  

I will be posting some study material for USMLE Step 1 that I am preparing for myself.  I find them helpful.  I am starting with Endocrine: peptide hormones.  I hope you will find them helpful.  If you want any specific topics to be posted, please let me know.  I will see if I have notes for them.   

Hormones

Three types of classification

1)      Control – is it controlled by brain or not

2)      Receptors

a.       Tyrosine Kinase linked

b.      Intracellular receptors

c.       Others

3)      Chemical composition

a.       Peptide/protein

b.      Steroid – derived from cholesterol

c.       Amine hormones – derived from

                                                               i.      Tyrosine or

                                                             ii.      Tryptophan

Properties Peptide Hormones

1)      Made in advance

2)      Stored in secretory vesicles

3)      Released by exocytosis

4)      Transport in blood by dissolved in plasma

5)      Short half life

6)      Activation of second messenger systems

7)      Modification of existing proteins + induction of new protein sysnthesis

8)      Examples: insulin, parathyroid

9)      Water soluble

10)   No carrier protein is need for transport EXCEPT:  IGF (lipid soluble – need a protein carrier)

Peptide Hormone Synthesis, Storage, and Release

1)      mRNA binds to ribosome and links amino acids into a peptide chain èpreprohormone (which is directed to RER by a signalling sequence).

2)      Prohormone is produced in RER by è an enzyme cleaving the signalling sequence.

3)      Prohormone passes from RER to Golgi

4)      Secretory vesicle è enzymes + prohormone bud off Golgi

a.       In the secretory vesicle prohormone is cleaved è active peptide + peptide fragments

5)      Secretory vesicles releases the fragments into the ECF by excocytosis (Calcium dependent)

6)      Hormone is in circulation; heading for the target organ. 

·         Secretory vesicles containing peptides are stored in the cytoplasm of the endocrine cell until the cell receives a signal for secretion. 

Post Translational Modification of Prohormones

1)      Examples:

a.       Prohormone – TRH (thyrotropin releasing hormone) contains multiple copies of the hormone

b.      Pro-opiomelanocortin:  prohormone splits into 3 active peptides + 1 inactive fragment.

c.       Proinsulin = insulin + c peptide (clinical correlate:  measuring the levels of the C peptide in the blood of diabetics to monitor how much insulin the pancreas is producing). 

Cellular Mechanism of action of peptide hormones

Peptide hormones are:

1)      Lipophobic

2)      Unable to enter target cell

3)      Binds to surface receptor complex – initiates the cellular response by means of signal transduction system

4)      Response of cells t peptide hormones is rapid because of the second messenger system

5)      Changes triggered by peptide hormones include opening or closing membrane channels and modulating metabolic enzymes or transport proteins

6)      Some peptide hormones also have long lasting effects when the second messenger systems activate gene synthesis producing new proteins.