Monday, October 12, 2015

Schwannoma

Standard Schwannoma,
Standard schwannoma
Antoni A and B areas



Extravasated RBCs




A cystic schwannoma


Sunday, October 11, 2015

On being nice all the time

Is being considerate, jovial and empathetic, i.e. being the 'nice guy' a requisite for, let's say, being happy? Acceptable? Successful?
Lets examine. Am I nice to everybody? I don't think so. I am not nice to most of the populace of this planet. I am not nice to most of the bacteria I meet every day. In fact, I hardly notice while my gastric juices savour them, or my mucociliary immunoglobulins feast upon them.
Unicellular creatures aside, am I being nice to eukaryotes? Coelenterates and porifers, maybe? When was the last time I said hello to a sponge, or a jellyfish?
Lets ascend up the phylogenetic tree. I don't give a flying damn about most annelids and arthropods. In fact, I despise them. They remind me the stateless form I have passed through my ontogeny. Since arthropods are the ruling species of the planet, my aversion towards them might cost me few high and mighty positions in the near future. But verily, even a threat of obscurity can not bring me to have a cup of coffee with a cockroach. They are simply too much for my taste.
What about the phylum that I belong to? I am not too fond of osseous fishes, except when they are served steamed. As remarkable as their adaptations are, those are the very reasons I positively despise amphibians. Who can stand a tongue that is attached to the front of the mouth? Yuck.
Reptiles, I am not sure. I tried speaking to a few in my room, but they don't seem to be sociable beings; their responses are tardy, and often morse coded in the form of 'ticks'. Birds are a little better in this regard; but have you ever seen a bird eat ? Hardly poetic, disemboweling a worm, you reckon.
Finally I arrive at my own class of suckers. Mammals. Those of the class who are worth befriending are overrated snobs, who will sleep most of the day and hunt in packs. The particular sub class of 'primates' that I belong to, is full of scurrying little creatures, noisy, bitching all the time, who will run at the first hint of threat (or throw excreta around, if its a particular kind of chimp). I don't really find their affiliation of any benefit at all.
The only surviving species in my genus (which is, by the way, responsible for the demise for all the others) is split into so many races that I find it hard to even keep track. I am often advised to keep everybody of this species in good humor, or at least talking terms. But one might ask, you feel,  what is so special about my own species?
I reframe the question. What is so special about my species that I have to be nice to them? Or, to put things in a different perspective,  what is so special about me that my being nice to anybody even matters?
Not a dissimilar argument can be put in the same vein. Why do I have to smile for a picture taken of me? I don't feel a need to project myself in any particular state of well being, even if only temporarily. In fact, most of the time I feel hungry, bitter, beaten and miserly. Have I become so blaise so that I have delegated the job of being myself to my 'selfie'?
I fail to see why, when I feel so (which is most of the time), I cant be my arrogant and stubborn self who is self deluded enough to accept that 'being happy' is not the final goal of life. I doubt if there is any 'goal','aim' or 'objective' at all to our existence. That we have to wear a smile and offer a chair to everybody around has been hard nailed into our combined psyche only because it is the most successful evolutionary strategy in our present environment. A millennium from now, and things might, you know ... deteriorate ... into the next ice age, and we are back to square one again: me hungry, me eat you, excuse me please.

Monday, October 5, 2015

The poor little non fermenter

Of all things .. a bacterium which does not ferment anything at all, but needs oxygen all the time

and is green too... 
can live eating only citric acid for indefinite periods (Simmond's citrate medium)

and does not ferment any sugar at all (Triple Sugar Iron medium)
Psedomonas aeruginosa is one of the wonders of evolution. The wikipedia page is quite interesting.

Sunday, October 4, 2015

'Pyogenic granuloma'

Granulation tissue type hemangioma, erstwhile 'pyogenic granuloma'; no pus, however.
 The stalk is the key
Also, capillary sized vessels with a central 'feeding' arteriole (hard to decipher in this pic). Notably, plasma cells.

Appendix of the upper entero - respiratory tract

Where else would you find squamous epithelium directly overlying lymphoid follicles?



Splitting hairs

The bulb of a follicle
Parts of a follicle (intradermal part only)
If you are missing the granular layer, note that it continues only upto a little below the acrotrichium (the intra-epidermal part of the follicle).  To quote Lever
"In the middle portion of the hair follicle, the so-called isthmus, which extends upward from the attachment of the arrector pili muscle (so-called bulge region) to the entrance of the sebaceous duct, the outer root sheath is no longer covered by the inner root sheath, which by then has keratinized and disintegrated. The outer root sheath therefore undergoes keratinization. This type of keratinization, referred to as trichilemmal keratinization (141), produces large, homogeneous keratinized cells without the formation of keratohyaline granules. Trichilemmal keratinization is found also in catagen and telogen hairs and in trichilemmal cysts and trichilemmal tumors."

Bankura

 Jaipur forest - Bankura and Banalata resort