catalase positive organisms

 

Owl’s eye appearance

 

Puedomonas mnemonic and illustration

Here's an illustration on pseudomonas for the desi students studying microbiology! 

STORY OF PSUEDOMONAS :

Here is you're friend , Psuedomonas

I am pink in colour __ gram negative

I have a long red hair __ flagella

I don't have an additional jacket __ non capsulated

I live on oxygen mask __ obligate aerobe

I play Holi everyday with red , green brown and blue _ pyorubicin , pyoverdin , pyomelanin, pyocyanin.Pigments produced by psuedomonas

My Diet chart __ biochemical reactions and culture media

Biochemical diet _

• Oxidase ka Bartha __ oxidase test positive

• Hugh leifson soup __ hugh leifson media __ glucose oxidation

• Cata cola __ catalase reaction positive

Culture diet _

• Nutrient shake _ In nutrient broth forms surface pellicle ( obligate aerobe)

• Nutrient cake __ nutrient agar _with green / blue colonies , sweet odor

• Red currant cake __ blood agar __ beta hemolysis

• Yellow McConkey sauce __ McConkey agar __ yellow colonies ( doesn't belong to enterobactericea )

• Cetrimide karela fry __ selective medium for psuedomonas __ cetrimide agar 

-Shreya HA

COVID - OMICRON

Hello friends!

This post is about omicron variant of COVID.

Why do we have to know about any new variants?

✓ more infectious than previous one?

✓ if it's more virulent?

✓ any diagnostic difficulties?

✓ treatment failure?

✓ does previous vaccine work for it?

Basically this OMICRON has more than 30 different mutations on surface of S1 or S2 spike protein with lineage number B.1.1.529 variant of concern (voc).

Preliminary data shows that it is highly infectious but the data is limited. We need to wait for further studies.

Most of the vaccines are targeting 'S' spike protein so antibodies are produced against 'S' spike. Risk of vaccine failure due to 'S' spike mutation is still a point of concern but data is limited now.

Diagnostics- most of the other targets (including N and RdRp genes) remain unaffected. These RTPCR tests detect atleast 2 different SARS-CoV-2 targets, which serves as a backup in case mutation arises. Current PCR tests can detect this variant. 'S' gene target failure can occur if not detected.

Severity of disease - more in immunocompromised and extremes of age groups.

Effectiveness of vaccines - Antibodies decrease severity and death .

Reinfection is higher with omicron.

Treatment - steroids and IL-6 receptor blockers are still effective.

So, be cautious but don't panic! 

That's all!

Dr.Madhuri 

Job's syndrome

Job's syndrome is also known as hyper- IgE syndrome.

It has autosomal dominant inheritance ( STAT3 gene).

Here is the mnemonic to remember its key features :

A - Abscesses of face and lungs by staphylococcus aureus ( pneumatocele)

B - Bone fragility

C - Coarse facies

D - Dermatological features like eczema.

E - Eosinophilia, increased Ig E.

Trick to remember important points: 

"Steve Jobs is a dominant person, interested in business STATs"

That's all!

Dr. Madhuri.

Babeosis mnemonic

This is how I remember babeosis is associated with Maltese cross appearance.

You know you love me, xoxo, gossip girl!

-IkaN 

Lyme's disease - a review

 Hi!

Lyme's disease/ Lyme borreliosis

A patient with a typical history of frequent visits to the woods with bull's eye rash, neurologic features, cardiac abnormalities, and musculoskeletal features.

Ampicillin-rash in infectious mononucleosis

 Hi!

Penicillins such as amoxicillin and ampicillin are currently not recommended in patients with infectious mononucleosis with bacterial secondaries (streptococcal tonsillo-pharyngitis). Why?

Histoplasmosis mnemonic

Histoplasmosis mnemonic

Bubonic plague mnemonic

Bubonic plague mnemonic 

COVID-19 Vaccine Development

The worldwide magnitude of the COVID-19 pandemic is ineffable; it is unsurprisingly compared to the Spanish flu pandemic, which ravaged the world during the First World War (adding fuel to the fire!). One of the pandemic's various positive impacts has been the unprecedented research collaboration and data sharing across the world. Such singular efforts made it possible to cut down the usual time to achieve an approved vaccine from 10⁺ years to less than a year.

To put things into perspective, it took 60 years from the time of the first polio outbreak to developing its vaccine; in the case of Ebola, it took 15 years. Vaccine candidates for SARS-CoV-1 and MERS did not receive the necessary impetus to advance into fruition. However, with SARS-CoV-2, the situation is very different. Global initiatives such as ACTIV (Accelerating COVID-19 Therapeutic Interventions and Vaccines), a public-private partnership comprising of bigwigs like CDC, FDA, EMA (European Medicines Agency), and numerous leading biopharmaceutical enterprises. Another project on a similar scale is Operation Warp Speed, which has invited comparison to the infamous Manhattan Project.

What is an "ideal" COVID-19 vaccine? There are three criteria from the immunological perspective: 1) It induces a robust humoral immune response that produces long-lasting neutralizing antibodies against SARS-CoV-2 antigens, 2) It generates a strong cell-mediated immunity that includes the production of memory T cells, 3) It should be free of any serious local or systemic adverse effects. Considering the logistics of vaccinating the entire world, there are three more criteria: 1) It should be easy to administer, preferably in one or two doses, 2) It should be easy to produce on a large-scale, 3) Its storage should be uncomplicated, ideally possible at room temperature.

 Source: Front. Pharmacol., 19 June 2020 | https://doi.org/10.3389/fphar.2020.00937

Let us discuss the vaccines that are currently in development. We all have heard about a few of them in the news and social media, namely, Pfizer, Moderna, Covaxin, Astra Zeneca, and so on. There are, impressively, 125⁺ SARS-CoV-2 vaccines in development globally. Broadly, there are six platforms currently being utilized for vaccine development –

1.   DNA

2.   mRNA (examples – Moderna, Pfizer)

3.   Protein (Subunit vaccines)

4.   Viral vector – replicating/non-replicating (examples - Oxford/Astra Zeneca, Johnson & Johnson)

5.   Live attenuated virus

6.   Inactivated virus

Almost all of the above models have targeted the spike glycoprotein, which is present on the surface of SARS-CoV-2, to interfere with the viral entry into a cell.

This article is an oversimplified summary of the vaccine development process. I haven't covered the vaccine platforms, molecular targets, and vaccine candidates in detail. With the advent of vaccine administration, whether it's Pfizer's or any other, there will be a massive surge in vaccine-related information. There will be challenges at every step, from distribution to underdeveloped areas of the world to alleviate the concerns of the skeptical anti-vaxxers. Let us hope that these vaccines start the end of the pandemic.

-Vinayak

TORCH syndrome + mnemonic

 TORCH syndrome is caused by congenital infection by a group of infectious agents. 

Respiratory fluoroquinolones

Why are moxifloxacin, gemifloxacin, and levofloxacin also known as respiratory fluoroquinolones?

Shingles vaccine

What do we know about the Shingrix Vaccine?

This vaccine is recommended for patients over the age of 50 years. It is a live attenuated vaccine. It is a

recombinant vaccine containing the glycoprotein E named RZV or Shingrix. Two doses are

required 2-6 months apart and can be safely given with influenza (flu) vaccine. History of chickenpox or varicella zoster doesn’t determine whether to give the vaccine or not because antibodies gained through the infection wanes with time.

Internship diaries: Perception of nipple discharge

A 60-year-old female complained of clear discharge from her right breast for one week. 

On examination, the right breast nipple was painful and there was clear fluid around the nipple. Expressing the breast produced no discharge. Incidentally, she mentioned a rash that was hurting on her right shoulder. The rash was a distinctive cluster of fluid-filled blisters with inflamed underlying skin, suggestive of shingles. 

Topics to read before PG entrance exams!

Hello Awesomites!

The aim is to help the students who want to give upcoming NEET PG Exam and are clueless about how to plan and prepare ?
I know my friend struggling day in and out for life in Covid wards. Exams doesn't matter now.
When they will have time in hand I want to help them out with plan beforehand. They are already brilliant enough to have been through all the challenges. :)

I know you can't predict what is important for this or next exams. Atleast with time in hand you can glance through some topics that contribute 70% of any exam. I am sharing the list 1st year subject I made during my preparation.

1.ANATOMY

• Embryology 

1. Pharyngeal arches
2. Neural crest derivatives
3. Oogenesis and spermatogenesis
4. Notochord and remnants 
5. Extraembryonic mesoderm
6. Diaphragm 
7. Cardiovascular system ( Abnormal subclavian artery)
8. Urogenital system 

• Histology 

1. Cerebellum
2. Osteoblasts
3. Urinary bladder epithelium
4. Cell junctions
5. Collagen types
6. cartilage
7. Tonsil,Lymph nodes, spleen,thymus
8. Stomach glands
9. Skin with sebaceous glands
10. Connective tissue types
11. Retina 
12. Salivary gland

• NEUROLOGY

1. Fornix 
2. Corpus callosum
3. Cranial nerves and its lesion
4. Brainstem syndromes (lateral medullary )
5. Foramen of skull
6. Facial nerve and trigeminal nerve
7. blood brain barrier
8. Functional area and functional columns
9. Parasympathetic ganglion 
10. Phrenic nerve and vagus

• GROSS

1.  Compartments of lower limb with nerve and blood supply
2. Blood supply of thyroid,oesophagus,ureter,Anal canal 
3. Waldeyer ring
4. External carotid artery
5. Circle of willis
6. Muscle of eye
7. Brachial plexus (Sensory and motor supply of upper limb)
8. Perineum
9. Cruciate ligaments
10. Vocal cords
11. Mediastinum
12. IVC tributaries
13. Cavernous sinus and superior orbital fissure 
14. Splanchanic plexus

2. BIOCHEMISTRY

• Inborn error of metabolism (Types,Enzyme deficient,hallmark feature,Investigation of choice and treatment)
• Rate limiting step 
• Carbohydrate metabolism (Glycolysis,Glycogen storage disease,Glucogenesis,glycogenolysis,PFK-1)
• Lipid metabolism ( Hyperlipoproteinemia and hypolipoproteinemia)
• Vitamin (Coenzyme)
• Electron transport chain inhibitor
• Heme metabolism and Porphyria
• Ketone body formation 
• Urea cycle disorder
• Competitive, non competitive and allosteric inhibitors
• Mitochondrial disorders 
• Amino acid disorder
• Lead poisoning
• Translation process 

3.PHYSIOLOGY

• Receptors
• Neurotransmitter and functions
• Second messenger
• Reflexes
• Baroreceptors and chemorecptors
• JVP 
• ECG And EEG
• Spirometry
• RAAS 
• Counter current exchanger and multiplier
• Factors affecting compliance of lung 
• Action potential
• Smooth muscle and cardiac muscle
• Channels and types 
• GIT hormones 
• Tracts and lesions(brown sequerd syndrome)
• LH,FSH,GH and insulin glucagon

 Following are the list of 2nd year topics.

1.FORENSIC MEDICINE

• Ballistics (Bullet ranges)
• Identification (female male, blood sample)
• Recent amendments in acts (POCSO act, MTP Act)
• Application of IPC,CrPC sections
• Postmortem changes
• Dentition And Xray of wrist elbow and pelvis to determine age
• Injuries -fracture of skull, RTA, Bruise
• Toxicology- Plant based image, Preservation of viscera, Snakes,Arsenic, OP poisoning,Mercury,cadmium,Cardiac poison
• Consent
• Grievous hurt and murder vs culpable homicide
• Seminal stains
• Dowry death and Rape
• Battered baby syndrome
• Plant Toxicology (castor,abrus,strychnine,Dhatura,Aconite,Oleander,Calotropis,Opium,Cannabis)

2. PATHOLOGY-

• Breast cancer, Lung cancer and Ovarian and testicular cancer
• CD markers
• Hemolytic anemia
• Vasculitis
• Endocarditis And MI
• Types of hypersensitivity reaction
• Platelet and coagulation disorder(ITP,TTP,hemophilias,vWD)
• Stains And vacutainers
• Transfusion reaction 
• Graft rejction
• Crohns vs Ulcerative colitis
• Necrosis, apoptosis and its variant
• Mode of inheritance
• Leukemia and lymphoma prognostic markers
• Renal histology and gross
• Liver histology and gross
• CNS tumors 

3.PHARMACOLOGY

• Antimicrobial Drug of choice and mechanism of action 
• Classification - aminoglycoside , MRSA And drugs for cystic fibrosis
• Hypolipidemic Agents 
• Asthma ( New drugs and guidelines)
• Arthritis (RA and gout)
• General pharmacology ( Pharmacokinetics,clinical trial,Pharmacodynamics)
• Concentration dependent kinetics and time dependent kinetics and post antibiotic effect
• Anti TB drugs
• Anti viral and anti HIV (anti hep B and C)
• Anti fungal
• CVS- MI ,HF, angina managment
• Endocrine- DM,Osteoporosis,SERM,SERD,Gnrh agonist
• GIT-Constipation (opioid induced,IBS related) ,Diarrhea,peptic ulcer
• CNS-Anti epileptic, Sedative,lithium toxicity,neurodegenerative disorder, side effect 
• ANS- Emergency medicines,anaphylaxis, receptors ,poisoning 
• Chemotherapy-Anticancer,monoclonal antibody,small molecules,kinase inhibitors
• Prostaglandins 
• Insulin 

4.MICROBIOLOGY-

• Sterilisation and disinfection (Indicator)
• Immunology (Antibody,complement deficiency,Primary immunodeficiency)
• Latest outbreaks (Zika,Congohemorrhagic fever,Ebola,Corona)
• Sexually transmitted infections
• Vectors
• Parasitology -Eggs
• Congenital infections-Toxoplasmosis,congenital syphillis,rubella,herpes,varicella
• HPV infection,HHV-8
• Bioterrorism
• Larva migrans,larva currens (cutaneous and visceral)
• CD4 counts and Opportunistic infection
•  HIV and TB
• Food poisoning
• Atypical bacteria treatment and infection 
• Dimorphic fungi
• Actinomycosis,Botryomycosis and eumycetoma
• Meningitis
• Exanthematous disease
• Neisseria,diphtheria,Listeria,bacillus anthrax,legionella,campylobacter jejuni
• Bacterial virulence factors,growth factors
• Rickettsial disease, spirochetes(weils ds) 
• Drug resistance mechanism

Following is the list of 3rd year topics.

1.COMMUNITY MEDICINE-

• Surveillance programs
• Sensitivity, specificity,PPV and NPV (Screening of disease)
• Types of studies 
• Odds ratio and relative risk ratio
• Bias
• Sampling 
• Biostatistics- central tendency  (Box and whisker plot )
•  Level of prevention 
• Vaccine and types (Toxoid and live attenuated)
• Demography and family planning
• Biomedical waste
• Health programmes ( RNTCP, HIV)
• Communication
• Nutrition and related programmes
• Disaster
• Null hypothesis,P value and alpha value
• Confidence limit 

2.OPHTHALMOLOGY-

•  Refractive errors (Astigmatism)
• Surgery and post op complication(Glaucoma,cataract,squint)
• Conjuctivitis
• Corneal ulcer (Bacterial,fungal and herpetic) (Stains)
• ROP and systemic retinopathy (Hypertensive and diabetic retinopathy)
• Retinitis pigmentosa and syndromes
• Retinal detachment and cause
• Retinoblastoma
•  Strabismus
• Optic neuritis
• Visual field defect 
• Blow out fracture and trauma to eye
• Glaucoma and drugs(Contraindication and indication)
• Managment of ptosis
• Light reflex and accomodation reflex and pupil
• 3,4,6 Cranial nerve
•  OCT ,Fluorescein angiograhy,tonometers,charts,
• Sudden loss of vision and gradual loss of vision differentials

3. ENT-

• Appearance of tympanic membrane in various disease
• Surgery (Tonsillectomy,Adenoidectomy,Mastoidectomy)
• Paranasal sinus
• CSF rhinorrhea
• Laryngeal disease (Papilloma,vocal cord paralysis, laryngeal muscles action, laryngeal cancers)
• Tracheostomy
• Abscess 
• Nasopharyngeal carcinoma
• Juvenile angiofibroma
• Test of hearing and vertigo
• Otosclerosis
• Cochlear implants
• Oral cavity cancers 
• cervical Lymph node  and neck dissections

 Following is the list of Final year topics.

 1.OBSTETRIC AND GYNECOLOGY-

• Pre-eclampsia (Definitions)
• HELLP
• PPH (prophylaxis and treatment)
• Perineal tear (Types and managment)
• Diabetes and anomalies scan 
• Shoulder dystocia maneuvers
• Molar pregnancy (High risk and low risk for GTN)
• Ectopic (Diagnosis, Investigation and managment)
• Abortions 
• Recurrent pregnancy loss (Investigations and causes)
• Cervical incompetence
• MTP
• Diagnosis and physiological changes of pregnancy 
•  Abruptio vs placenta previa vs Vasa previa
• Heart disease
• MgSO4 and drug
• Fetal monitoring -NST,BPP,doppler
• Twins and complications
• Labor-stages,partogram
• Placenta types and associated pathology
• Rh incompatibility
• Amenorrhea (primary and secondary)
• Mullerian anomalies (Class)
• Asherman, AIS,Gonadectomy indication
• Puberty and precocious puberty
• Menopause (Hormone replacement therapy guidelines) 
• Postmenopausal bleeding and premature ovarian failure (Levels of FSH)
• Semen analysis (Evaluation and IUI and TESE)
• PCOS -Diagnosis,drugs
• Endometriosis
• Cervical,vulval,ovarian,endometrial cancer,Fibroid
• Krukenberg
• PID
• Prolapse 
• Emergency contaceptives
• IUD
• Absolute contraindications in whole subject
• Female sterilisation  

2.PEDIATRICS-

• Developmental milestones
• Neonatal reflexes
• Neonatal resuscitation
• Jaudice,sepsis,Hyaline membrane disease
• Congenital infections-TORCH
• Vaccines(IAP and NIS)
• Diarrhea,pneumonia,dehydration managment
• Pediatric epilepsy
• Febrile seizure (Risk factors,recurrent risk,prohylaxis)
• Severe acute malnutrition
• Rickets
• meningitis
• Neuro-Cerebral palsy and neurocutaneous syndrome
• Pediatric vasculitis-HSP and Kawasaki Disease
•  Nephrotic syndrome
• Congenital heart disease( VSD,TOF,TGA and ductus dependent CHD)
• Trisomies
• Hypoxic Ischemic encephalopathy VS Periventricular leukomalacia
• Fluid managment including shock managment in children
• Childhood pneumonia, Epiglottitis, Acute laryngotracheobronchitis
• Microcephaly and macrocephaly 
• Hydrocephalus and Neural tube defect  
• Fetal alcohol syndrome,warfarin syndrome

3. ANESTHESIA-

• IV anesthetic agents (Propofol)
• Day care surgery (Drug of choice)
• Venous air embolism
• Local anesthetic (Remember concentration also)
• Vaporisers color 
• Inhalational agents 
• Monitoring (Capnography)
• Color coding of cylinder
• Circuits
• Mallampati and ASA grading
• Premedication duration of stoppage and continuation
• Muscle relaxant
• Airway devices
• Endotracheal tube (formula)
• Epidural vs spinal anesthesia (Level of blocks)
• Modes of ventilation

 4.DERMATOLOGY-

•  Pigmentation Diseases 

1. Hyperpigmentation
2. Nevus (Nevus of ota/mongolian spot/CMN/AMN)
3. Melasma
4. Acanthosis nigricans
5. Becker nevus
6. Hypopigmentation -PKDL/Pityriasis versicolor/alba/Hansens
7. Depigmentation-Vitiligo/Contact leukoderma

• Signs (Auspitz,nikolsky,bulla spread sign)
• Histopathology of psoriasis and lichen planus
• Mast cell disorder-Urticaria pigmentosa image
• Papulosquamous disease - Psoriasis ,lichen planus
• Treatment of Psoriasis
• STD (Syphillis,chancroid,donovanosis,Herpes genitalis,syndromic approach)
• Microbiology of STD organism( Dark ground,school of fish,Tzanck smear,Donovan body,Gonococcus)
• Drug Reaction -Fixed drug eruption, erythema multiforme,SJS/TEN
•  Blistering disease 

1. Pemphigus(clinical treatment)
2. Bullos pemphigoid
3. dermatitis herpetiformis
4. Histopathology of blister level and Direct immunofluorescence image

• Infections

1. Fungal (Tinea /pityriasis versicolor)
2. Hansens 
3. TB
4. Viral (HPV/HHV/Molluscum contagiosum)

• Hair disease-Alopecia images,DLE,trichotillomania
• Acne,Rosacea
• cutaneous markers of internal malignancy

5.RADIOLOGY-

• Emergency radiology-RTA,splenic injury,FAST,Perforation
• Radiological anatomy especially applied aspect
• CNS tumor
• Bone tumor
• BIRADS
• TIRADS
• Radiation physics and acute radiation syndrome
• Radiotherapy basics
• Contrast in various studies
• USG and doppler
• Doppler waveforms

6.ORTHOPEDICS-

• Knee joint (Everything)
• Shoulder dislocation
• Bone (Oncology+radiological picture)
• Pediatric Hip(Rdaiology +managment)
• Infections(TB,Osteomyelitis)
• CTEV
• AVN
• Tennis elbow and dequeverian
• Eponyms and test
• Blood supply of femur
• Pseudoarthrosis
• Genu varum/valgus,cubitus varus/valgus
• malunion 
• Instruments

7.SURGERY-

• Glasgow coma scale (Changes)
• Burn
• Cannula color coding 
• Triage
• Trauma
• Incisions,suture,foleys,NG tube,Knots,Scores
• Latest updates in breast cancer,thyroid and hepatobiliary cancers,Pancreatic cancer,stomach,colorectal cancer
• Bed sores staging 
•  Renal stones managment
• Gall stone managment and surgical complication
• Bariatric surgery
• Acute pancreatitis managment 
• Upper GI and lower GI bleed management and causes
• Aortic aneurysm
• Meckel diverticulum
• Wound classification
• Cancer-(Breast,rectum,stomach,oesophagus,HCC,prostate,thyroid)
• Cancer follow up duration 
• Carcinoid and GIST and gastrinoma

 8.MEDICINE-

•  ECG visuals
• Cardiac emergencies-Arrest,Unstable angina,MI,Arrhythmia,Dissection
• Respiratory emergency-Pulmonary embolism,pneumothorax,Asthma 
• Stroke
• Meningitis (Bacterial,viral,aseptic)
• Approach to patient in Coma
• Seizure
• Electrolyte imbalance
• ABG
• Hypertension and its emergency and management
• Murmurs and valvular lesions
• Pericardial d/o
• hepatitis(Viral,autoimmune)
• Non alcoholic and alcoholic liver disease
• Glomerular disease
• UTI
• CKD
• DM (management of different complications)
• Neurodegenerative d/o ,neuropathy,myopathy
• Septic shock guidelines
• GBS
• Poisoning 
• New asthma guidelines
• RTA and Inherited channelopathies
• MEN syndrome
• SIADH, DI,Pheochromocytoma
• AIDS defining illness
• Connective tissue disorder
• Infective endocarditis and rheumatic heart disease
• Prakinson and alzheimers
• IBS,UC ,Crohns
• Cardiomyopathy
• Jones and dukes criteria
• dyslipidemia management 

10.PSYCHIATRY-

• General psychiatry (terms and its meaning )
• MMSE
• Psychotic disorders

1. Schizophrenia
2. Delusional d/o- Named syndromes (Capgras,Fregoli,Othello,Ekbom)

• Mood disorder (Treatment is very important)

1. Mania
2. Depression
3. Bipolar

• Neurotic disorder 

1. Anxiety disorder
2. OCD related disorder
3. Dissociative disorder
4. Trauma and stress related disorder
5. Somatoform disorder

• Substance abuse and deaddiction
• Organic mental disorder(dementia)
• Sleep disorder
• Eating disorder
• Sexual disorder
• Personality types and disorder
• Drugs (SSRI and its sideeffect)
• Psychotherapy types and choice
• Defence mechanism  

You can edit this according to you. 

Hope it will help.

-Upasana Y.

Zika virus mnemonic

Clinical vignette: Meningitis due to Listeria monocytogenes

Hello

Listeria monocytogenes is the 3rd most common organism that causes bacterial meningitis.
Cephalosporins do not cover this gram - positive bacteria under its spectrum. More aptly saying, the cephs do not kill this bacteria. So, especially in high-risk patients such as neonates, elderly, and the immunocompromised, cephalosporins are given in combination with ampicillin, and never alone.

Ceftriaxone is avoided for use in neonates due to its decreased biliary metabolism and sludging.
The choice of ceph in neonates and other high-risk groups in the case of meningitis is cefotaxime.

That's all
- Jaskunwar Singh

COVID-19: Trained immunity from BCG vaccine

Would BCG vaccination really help in immunizing up against SARS-CoV-2?

Let's dig in. 

BCG is a live-attenuated strain derived from an isolate of Mycobacterium bovis used widely across the world as a vaccine for tuberculosis (TB). But that's not all, BCG vaccination is a potential goldmine against so many diseases.

COVID-19: Coronavirus and hemoglobin

Hello Awesomites!

Please refer to the diagrams for better understanding.

Why do we have abnormal hemoglobin-related biochemical indices in COVID-19 patients?
Reports demonstrate that the hemoglobin and neutrophil counts decrease in most patients with SARS-CoV-2 infection, and values of serum ferritin, erythrocyte sedimentation rate, C-reactive protein, albumin, and lactate dehydrogenase increase significantly.

What makes hemoglobin an attractive molecule for the coronavirus?
Porphyrins!

Porphyrins in the human body are mostly iron porphyrins i.e heme. And a lot of heme is not free, but bound to hemoglobin. Viruses require porphyrins to survive. Therefore, the novel coronavirus targets hemoglobin, attacks heme, and hunts porphyrins.

Structure of SARS-CoV-2

Image by Upasana Yadav

The possible mechanism is that orf1ab bound to the alpha chain and attacks the beta chain, causing conformational changes in the alpha and beta chains; ORF3 attacks the beta chain and exposes heme. ORF10 then quickly attaches to the beta chain and directly impacts the iron atoms on the heme of the beta chain. The heme is dissociated into porphyrin, and orf1ab finally captures porphyrin. Orf1ab plays a vital role throughout the attack. Attack of oxidized hemoglobin by viral proteins leads to less and less hemoglobin that can carry oxygen. The invasion of viral proteins on deoxidized hemoglobin will cause less and less hemoglobin that can carry carbon dioxide.

This study found that ORF8 and surface glycoprotein had a function to combine with porphyrin to form a complex, while orf1ab, ORF10, ORF3a coordinately attack the heme on the 1-beta chain of hemoglobin to dissociate the iron to form the porphyrin. This mechanism of the virus inhibited the normal metabolic pathway of heme, and made people show symptoms of the disease.

What causes the high infectivity of the novel coronavirus?
Medical workers have detected the novel coronavirus from urine, saliva, feces, and blood. The virus can also live in body fluids. In such media, porphyrin is a prevalent substance. At the beginning of life, virus molecules with porphyrins directly move into the original membrane structure by porphyrin permeability. This study showed that the E2 glycoprotein and Envelope protein of the novel coronavirus could bind well to porphyrins. Therefore, the coronavirus may also directly penetrate the human cell membrane through porphyrin. (Means If the virus can bind with porphyrins, it can enter these secretory cells without ACE2 receptors by using the membrane permeability)

What is the importance of knowing the above information?
The drugs based on this mechanism: Chloroquine and Favipiravir.

The primary function of the Envelope protein is to help the virus enter host cells. The primary role of Favipiravir is to prevent the virus from entering host cells and catching free porphyrins. Favipiravir's ability to improve respiratory distress is lower. Favipiravir can only prevent the binding of Envelope protein and porphyrin.

Chloroquine could prevent orf1ab, ORF3a, and ORF10 from attacking the heme to form the porphyrin and inhibit the binding of ORF8 and surface glycoproteins to porphyrins to a certain extent, effectively relieve the symptoms of respiratory distress.

The infectivity of the nCoV pneumonia was not completely prevented by the drugs, because the binding of E2 glycoprotein and porphyrin was not inhibited.

Note for Diabetic patients
Diabetic patients and older people have higher glycated hemoglobin. Glycated hemoglobin was reduced by the attack, which made patients' blood sugar unstable. Since the porphyrin complexes of the virus produced in the human body inhibited the heme anabolic pathway.
Written by Upasana Yadav
(Courtesy:-Thank you Ikan for all the help) 

References:
1. Wenzhong, liu; hualan, Li (2020): COVID-19: Attacks the 1-Beta Chain of Hemoglobin and Captures the Porphyrin to Inhibit Human Heme Metabolism. ChemRxiv. Preprint. https://doi.org/10.26434/chemrxiv.11938173.v5
Link to the article: https://chemrxiv.org/articles/COVID-19_Disease_ORF8_and_Surface_Glycoprotein_Inhibit_Heme_Metabolism_by_Binding_to_Porphyrin/11938173