Amoebas - Shapeshifters of the microworld

Amoebas are free living eukaryotic organisms capable of changing their shape in order for it to move and feed. This is done by extending cellular projections called pseudopodia (see image). When the amoeba moves it uses these projections as a form of conveyor belt stretching towards the desired way of movement and the cell then fills the pseudopod with its insides called the endoplasm creating a sort of rolling movement as seen in the video below. When feeding, the organism will surround the food with its cell membrane and absorb it into its cell body where it is digested. A big part of the endoplasm is made up of these ingested particles as well as cellular organelles such as mitochondria and the nucleus containing the DNA.

Christmas spirit

To create a Christmas atmosphere through the microscope’, three small amounts of chemicals were dissolved in some tap water. These include aluminum nitrate, ammonium dichromate and copper sulphate.

Put a few drops of this solution on a microscope slide and let the water evaporate slowly. With a little patience, beautiful images can be seen through the microscope, using crossed polarizers and a lambda plate.

The mix of chemicals creates the most bizarre crystal shapes, some of which were captured on the sensitive plate using photo-stacking.

Merry Christmas!

© www.willemsmicroscope.com

Toxic Taxus baccata

Taxus baccata has deep dark green needles all year round. It is an evergreen tree that is also often used as a hedge. In winter, Taxus bears red fruits that are much loved by birds, but very poisonous to ungulates.

Taxus baccata is usually a sturdy shrub that, if given space, can grow into a tree. Growth is slow but eventually the tree can reach a height of about 15 to 20 meters with a width of 12 to 15 meters. The species is widely used for hedges and also for topiary. Bulbs, cones, columns and even animal shapes are available. Taxus can tolerate very strong pruning, even down to the perennial wood.

Bdelloid rotifers - An entire class of animals with no males

We have previously looked at the microscopic animals called Rotifers in general, but today we are going to take a closer look at a specific class of rotifers called Bdelloidea with quite a unique way of living. Bdelloid rotifers are extremely common all over the world where they can be found in different freshwater habitats like ponds, streams, moss, and garden birdbaths where they can be found in enormous amounts from time to time. These animals are incredibly tiny with a size of only 150 - 700 microns when fully stretched. Like other rotifers they feed on microalgae, bacteria, and single celled organisms. So far they sound just like other rotifers, however they are very different in a few ways.

Boost your resistance

At the time of the Corona crisis, many people resort to remedies to increase resistance to disease, such as vitamin C and Multi vitamin tablets. These, in this case foam tablets, contain many other substances besides the vitamins. Although the subject ‘vitamin C’ has been used many times in microscopy, it is still fun to view the crystals of these substances under the polarization microscope.

So, no sooner said than done, the tablets are now up for grabs at home anyhow. Dissolve a tablet in water, filter the solution, heat a few droplets of the solution on an object glass over a spirit burner in order to saturate it by evaporation. Let it crystallize patiently, put a cover glass on it and move it under the microscope.

The male Pine Cone

A Pine Cone is a scaly trimmed woody cone fruit of a coniferous tree. There are more than 100 types of coniferous trees. These produce both male and female cone fruits. The male pinecone is the smallest, contains pollen and only lives for a few weeks. The female pinecone is larger and contains (if fertilized) seeds.

Nematodes - The most common animal on earth

Around 80% of all animals on the planet are microscopic worms called nematodes, more commonly known as Roundworms. In fact, if you go outside and take a teaspoon of soil you will have caught about 50 of them. However, these tiny organisms are not just present in the soil, but can also be found in aquatic habitats, in moss, on trees and rocks, and almost all other places on the entire planet, from deep oceans, to high mountains.

Čechite, a rare vanadate from the Ulldemolins mines (Catalonia)

Čechite is a very rare lead and iron hydroxylvanadate, with the formula PbFe²⁺(VO₄)(OH), which has been found in very few localities worldwide. The first world location in which it was determined was in the Vrančice mines, in the Czech Republic, in the early 1980s. It has subsequently been found in Italy and the United States. It has no industrial interest, despite the fact that vanadium is a strategic element, since this mineral occurs in small quantities. 

This species usually appears as small tabular to equidimensional crystals, with a black color and a resinous to submetallic luster. The best crystals known until recently were those of the Czech Republic.

A curious caterpillar in the moss

In The Netherlands there are many working groups that regularly make an inventory of the mosses present in nature. For this purpose, the natural landscape is divided into square sections of 1 x 1 km that are characterized by nationally determined coordinates. In such a section it is observed which kinds of mosses occur in it. Many mosses can be identified on the spot. Here, people often use a magnifying glass. Sometimes the determination has to be done at home with the help of a microscope. The results of such an inventory are centrally placed in the "NDFF Verspreidingsatlas" (distribution atlas): www.verspreidingsatlas.nl. This is a database that has been made possible by various nature organizations, with the aim of following the development of the mosses flora under the influence of the environment in the Netherlands.

Synura - The golden algae

When we hear the word algae many of us associate that with the color green. And some algae like desmids, are in fact green. But there are a lot of different kinds of algae, and far from all of them are green. Some are red or red and green like haematococcus, some are blue-green like spirulina, while others are yellowish, brown, or even golden.

A common pest

Rosebay willowherb or Fireweed - Chamerion angustifolium - is a very striking and widespread plant species. During flowering it is easy to recognize. The upright plants have a cluster-shaped inflorescence at the top that tapers to a point. The color of the flowers is purple or purple-red. The separate flowers in the cluster are somewhat symmetrical on both sides because the top two petals are somewhat smaller than the bottom two. The scattered leaves are narrow and lanceolate and closely resemble the leaves of Willows.

Motic Path Case - Granulomatous disease of peritoneum

GRANULOMATOUS DISEASE OF PERITONEUM MIMICKING CLINICALLY A PERITONEAL CARCINOMATOSIS.

A 52 year-old woman, with a background of surgery by pelvic endometriosis two years before, was submitted for showing symptoms of abdominal distension with pseudo obstructive episodes and malaise. Apart from endometriosis, there was no a history of chronic inflammatory diseases or other interesting pathological events. At the physical exam, ascites is discovered coinciding with radiological study by abdominal scan (SC), which reveals multiple and heterogeneous nodules at the peritoneal surface. The clinical diagnosis was of peritoneal carcinomatosis. A laparoscopic study was realized in which no other abdominal abnormalities were perceived apart from the irregular peritoneal thickening, suggesting tumour process. Two biopsies of different nodules were made.  During histological exam, no neoformative tissue was found. On the contrary, the global alteration consisted of multiple isolated or confluent epithelioid granulomas in a fibrotic background. Basically they were made of histiocyte aggregates and less often multinucleated giant cells. Neither central necrosis nor characteristically morphological signs concerning to specific inflammatory disorders were seen. Specific stains such as Ziehl-Neelsen, Periodic Acid Schiff, Giemsa or Methenamine Silver did no visualized pathogen germs. In addition, in order to rule out tuberculosis, a PCR for BK bacilli was also negative. After the fact that specific aetiologies were discarded, the patient is being treated by anti-inflammatories and she is having a slow but good response.

Delimited by a narrow layer of fibrous tissue with mature lymphocytes.

Neither central caseous necrosis nor other specific histological characteristics are seen. 

Arcella vulgaris has caught Synura

This testate amoeba lives in the mud and vegetation in standing water and also in the bottom, between algae and other plants. Arcella Vulgaris is a testate Amoeba with loose pseudopodia protruding from the pseudochitine shell. Testate amoebae are amoebae with an umbrella-shaped hard cover. The cover is for protection and is excreted by the animal itself. They nourish on diatoms, unicellular algae, animal protozoa such as flagellates and ciliates.

Nettles - The healthy stingers

The plant urtica dioica, more commonly known as the stinging nettle, is a plant many of us are unpleasantly familiar with. The quite fitting name ‘nettle’ comes from the anglo-saxon word ‘noedl’ which means ‘needle’ and the latin ‘urtica’ means ‘to burn’. The plant is found worldwide but was originally native to Europe. At its tallest, the nettle grows to around two meters and are equipped with medium sized leaves. Despite many myths both the stem and the leaves are able to sting you as both are covered in the tiny needle-like structures called trichomes or spicules responsible for the burning sensation you get after contact with the plant.

Viburnum's annoying ‘hair’

The Viburnum rhytidophyllum or Leatherleaf plant is native to central China and is especially decorative along the roads, even in the shade. The plant is a shrub 3 to 4 m high. The leaves are lance-shaped, 15-20 cm, pendulous, leathery with relief, dark green on top, light green and hairy. ‘Hairy’; that is, occupied with stellate (star-shaped) nonglandular trichomes. Trichomes can have many functions like defence against harmful insects, humidity regulation and even a sensory function. 

Lengenbach, rare minerals in Switzerland

In the Swiss region of Valais (Wallis) a mine known as Lengenbach is “exploited”. From this small quarry, with a few more than 10 meters of mine face, minerals are not extracted for industry, but for research.

The exploitation works, which began in the s. XIX, are carried out in Triassic dolomites, rich in sulfosalts of Pb, Tl, Ag, and Cu, very rare worldwide, along with numerous other interesting and aesthetic mineral species. Of some of these sulfosalts a single specimen is known. It is the type locality (TL) of 46 different mineral species, making it the fifth most prolific locality in the world (TL: indicates that a mine is the first place in the world where a certain mineral species has been described).

Cutaneous Histiocytoma dog

Histiocytoma

A cutaneous histiocytoma is a benign skin tumor. It consists of an accumulation of a large amount of histiocytes in the skin. Histiocytes are cells that are involved in the immune system. We usually see histiocytomas in young dogs up to the age of 3 years.

In a short time there is a skin tumor ranging from a few millimeters to a few centimeters. Usually they are at the head, lips, ears, neck, legs and chest. They are not painful and do not cause itching, unless there is an inflammation. If they start to itch because of the inflammation, it means that the body is cleaning them up. Regularly this swelling looks fiery and choppy.

Some of the smallest crustaceans in the world

Crustaceans are a huge group of animals living all over the world. There are more than 67.000 known species which dramatically vary in size from around 0.1 mm to almost 4 m. Most are aquatic animals, like crabs and shrimp but some are terrestrial like the woodlouse. All crustaceans have a tough exterior called an exoskeleton used to support and protect their body. This armor is mainly made up of long polymers called chitin combined with calcium carbonate to make it hard. Here we will look at a few of the smallest crustaceans you might encounter in a water sample. The first one we take a closer look at is a copepod.

It is covered in symbiotic algae. The copepod is surrounded by 

younger individuals at different stages of development.

Flatworm digestive tract

The digestive tract of the flatworm, as shown here of a representative of the Dugesia genus, is not very complicated. 

This type of flatworm lives in fresh water. Flatworms absorb their food by mouth in the middle part of their lower body. A small tube shoots from the center of their body at the food and sucks it into the Pharynx. The fresh food is sent to and through the 'intestine', also known as the gastrovascular cavity. There the food is digested. It is spread on all parts of the worm, where the nutrients are needed for growth.

Mastocytoma dog

A mast cell tumor* (mastocytoma) is a potentially very malignant tumor of mast cells in the skin. This tumor is the most common skin tumor in dogs. It mainly occurs in the skin but not only there. A mast cell tumor can look very different. The tumor can be in the skin or under the skin. The presentation is usually like a solitary solid (sometimes soft) bump with a diameter of a few mm to as much as 10 cm. The overlaying skin is often alopecia (bald spot), erythematous (abnormal red), sometimes eroded or ulcerated (open wound). One should not squeeze the tumor; histamine granules* can be released (degranulate) This can cause an anaphylactic reaction, which means that the animal can get into shock. As mentioned, the tumor can be red in color, contain extra pigment or have the normal color of the skin.

As with all bumps on the skin, it is never possible to determine on the outside whether there is a tumor and what kind of tumor it is. Therefore, further investigation must also be carried out in the event of a suspicion of a mast cell tumor. This can be done by means of a FNAB (Fine Needle Aspiration Biopsy) or by means of a tissue biopsy. Cells are taken from the bump and these cells are assessed under the microscope (by a cytologist) as in this case. A FNAB gives a correct diagnosis in a large number of cases, but in all cases a tissue biopsy gives a correct and sometimes more extensive diagnosis.

Aeolosoma

Aeolosoma are very small annelid freshwater worms found all over the world. Even though these worms have been known for almost 200 years we do not know much about them. In fact, we know so little that there is still uncertainty on how to spell its name. Some will spell it aeolosoma, while others spell it aelosoma. 

Another mystery yet to be solved is which class of worm it is. Some place it in the same class as earthworms, the oligochaetes. Others place them in the polychaetes with bristle worms, and still others think they belong to their own separate class on the taxonomic tree of life. However it seems like the majority describes them as polychaetes.

Video showing aeolosoma at different magnifications with different microscopy techniques. 

Notice the almost complete clone in the back end of the worm

Wood - a fascinating material

 INTRODUCTION

Wood is a wonderful material. It embodies the beauty and the odor of forests, the ecology of a natural building material and the microscopic aesthetics of a complex 3-dimensional anatomical structure.

The secondary cell wall of plants, constructed of parallel cellulose fibers embedded in an amorphous matrix is impregnated with lignin and minerals as a stabilizing factor for altitude records, e.g. the “Tall Tree”, 112 Meter height, a Sequoia tree from the California National Park. Shrubs and herbs use this principle to a lesser extent.

About tree dimensions. Look for the human. (Source)

For the increasing lack of sand and therefore of concrete as a construction material architects today tend to wood as an alternative. Asian engineers are famous for their buildings made with the help of a bamboo scaffold.

Hong Kong building with bamboo scaffold. (Source)

In Europe, architects are increasingly working with natural materials to follow the ecological demands of their customers. They reinvent proven technology with wood as a basis. From a wooden house to a wooden skyscraper: a big step.

The concept for Germany’s first high-rise building in Germany made of wood. (Source)

WOOD MICROSCOPIC VIEWS

All attributes of wood can be derived from a microscopic analysis. The odor of a Christmas tree (resin channels!), the characteristics of furniture wood, the mechanical stability of timber. A tree trunk with its 3-dimensional structure needs 3 cutting planes to be fully understood: a cross section, a tangential cut, a radial cut.

• THE CROSS SECTION

The cross section is most easy to understand: 

How can I ensure a clean microscope?

INTRODUCTION

A microscope is a powerful scientific instrument. Science education in teaching institutes and universities is deeply depending on this instrument. Organizationally and financially justified, the students/users share the common instruments of a classroom.

Besides the well-known procedures to maintain the performance, in Corona times additional care is needed to avoid spreading the virus. Time to update our care recommendations.

IMPORTANT MICROSCOPE CONTACT AREAS

(1) Objectives

(2) Eyepieces

(3) Condenser

(4) Collector cover glass

(5) Glass slide including the cover slip

In the case the microscope is combined with a camera attached, you may find dirt.

(6) On the lenses of the camera adapter (C-mount)

(7) On the protection glass (IR filter) of the camera sensor

Attention: All inner surfaces of the optical elements are strictly taboo! Do not disassemble any part of your microscope for cleaning purposes. You only have access to the outer surfaces of these components. Disassembly will significantly affect the performance of your instrument and will void the terms of warranty. If you notice a malfunction in mechanics or electrics, please contact your nearest Motic supplier.

Just a beautiful preparation

Here we see the images of a beautiful preparation made by Mike Smith. The cross section trough the ovary of Buddleia globosa shows many details. Note that the ovary (and later the seed capsule) is covered in tangled hairs (stellate-tomentose) and how the base of the style is also hairy. The second fluorescence image shows this in detail.

Brought home from a trip to the Medina of Tunis

This tick appeared during unpacking travel luggage at home. The tick was neatly stored in a small bottle filled with alcohol and sent to the National Institute for Public Health and the Environment in the Netherlands, to have it identified. It is the Rhipicephalus sanguineus or Brown dog tick.

This species lives in countries with a warm climate in every continent and therefore also in countries around the Mediterranean Sea. Especially in Spain, France and Italy, people are regularly bitten by this brown animal.

Dogtooth Calcite

Calcite (CaCO3) is a mineral found in many different crystal forms. Dogtooth Calcite are calcite crystals that grow in a certain crystal form. This shape is long, pointed and resembles a dog's canines. This crystal shape comes in a wide variety of sizes, and of course the small ones are more common than the big ones. The growth of very large crystals, also called Dogtooth Spars, takes an extremely long time in undisturbed, calcite-rich water. Dogtooth Calcite crystals are quite common. Normally they are quite small, say a few millimeters.

In the photos we are introduced to the fluorescent properties of this mineral. Long pass fluorescence filter blocks were used for the exposure of the mineral sample: DAPI 375 nm excitation wavelength (UV) and MB 480 nm excitation wavelength (blue light).

Image stacking - for increased depth of field

A microscope is not only useful when investigating microscopic specimens. To see the fine details of insects and other larger specimens, a microscope is also extremely handy. However, the depth of field (DOF) is very shallow and only a small portion of the specimen can be in focus at each time. This is not due to bad objectives or microscope, but due to the high magnification. But this problem can easily be overcome by the use of an image processing method called focus stacking.

Illustration of the shallow depth of field.
The focus plane is at the top of the right eye and mouth

Right through a moss animals colony

Bryozoans, commonly known as moss animals, are a group of primitive animals that almost always live in colonies. There are about 5000 species, which occur in both fresh and salt water, at sites that are characteristic for them, such as ponds, lakes, ditches, streams and rivers, as well as water cellars of water companies. The colonies they form resemble plants. They are flat mats or branch-shaped colonies that are very variable in shape, and can grow to about 30 cm high. They need a hard substrate such as aquatic plants, reed stems, sticks, stones, cans, old boots and the like. Stones and especially wood seem more popular than glass and metal. They cling to any surface that provides a grip.

Here we see a cross section of a Plumatella colony that has formed around the stem of an aquatic plant. The colony is compact and zooids contact each other with their lateral walls. The large number and irregular arrangement of zooids means that almost every part of the animal is present in one place or another in the cross section.

Haematococcus pluvialis - The red colored green alga

Haematococcus pluvialis is a single celled green freshwater alga found all over the world. Each cell is encased in a transparent capsule and varies in size from 10-50 microns depending on its life cycle stage, but most are around 20 microns. H. pluvialis can be found in two major stages, active and inactive. In the active stage the algae are motile and move with two long whip-like projections called flagella. In the inactive stage the cells become non-motile encased cysts which are able to tolerate periods without water and huge temperature fluctuations. One of the protective strategies the algae use during the non-motile stage is the production of a molecule called astaxanthin.

Typical for dicotyle plants

On the photos we see a cross section of the root of the Ranunculus. The specific arrangement of primary tissues shown here, is typical of dicotyle plants.

Plasmacytoma dog

In the preparation shown here a biopsy taken from the skin of a seven-year-old Golden Retriever, many plasma cells can be seen. We also see anisocytosis and anisokaryosis. The coarse chromatin in the nucleus indicates that something may be wrong. Plasma cells are part of the immune system and are usually found in lymphatic tissue and mucosal surfaces. Plasma cells are immunoglobulin-producing cells that originate from B lymphocytes and are characterized in particular by a large amount of cytoplasm, an eccentrically located nucleus and a perinuclear optically empty court.

About blood

Blood forms the transport system of the body. It flows continuously to supply oxygen and nutrients to tissue and to remove waste products. It also plays an important role in the defense against pathogens in the body and ensures a constant body temperature. Blood is an important transport medium for hormones. So blood literally means life!

About half of the human blood is plasma. Blood plasma mainly consists of fluid and proteins. The other half of this blood consists of blood cells, namely: red blood cells, white blood cells and platelets. For example, the red blood cells transport oxygen and carbon dioxide through the body. The white blood cells make harmful substances and pathogens recognizable and harmless. Platelets provide crusting to a wound.

Rotifers - Some of the smallest animals on earth

Rotifers are some of the smallest animals on the planet. Most measure under 500 microns, but their size can range from only 50 microns to around 2 mm (2000 microns). They are some of the most common microscopic animals, living all over the world in all kind of environments, like freshwater, saltwater, in moss on trees and in the soil underneath your feet. Rotifers are made up of roughly 1000 cells, some of which are specialized to form organ systems. Despite their incredibly small size they have eyes, a small brain and nervous system, and a dedicated digestive system just like us.

A find on the beach

The shells or shields on the back of the various species of cuttlefish Sepia spec. consist of brittle lime (sometimes also referred to as Sea Foam) and are softer on one side than on the other. There is gas between the layers of lime, so that they float and often wash up on the beach.

Cuttlefish are good swimmers who can cover large distances. Sometimes animals wash ashore on the coast, but more often loose back shields. They have good buoyancy and can wash up on the beach at a great distance from the place where the animal died.

Lumbriculus variegatus - The blackworm

Lumbriculus variegatus, more commonly known as a blackworm, is an oligochaete worm found in many freshwater habitats across Europe and North America. It is technically not microscopic, but very small and to see the details and internal anatomy, we have to use a microscope.

Blackworms are only about a millimeter in thickness, but they are able to reach a length of up to 10 centimeters. Blackworms eat things like microorganisms and decaying plant material. To digest its food, the worm has a dedicated digestive tract running down the center of the body. This is like a miniature version of the human digestive tract and works in basically the same way by squeezing ingested food through the tube with rhythmical massaging movements called peristalsis (see video further down).
Another clearly visible structure in the worm is its circulatory system. The animal lacks a true heart, but instead pumps blood through the blood vessels with several pairs of muscularized vessels able to contract and work as a heart.

Myriophyllum beautiful but a nuisance

Myriophyllum or Red stem is a water plant that prefers to take root on the transition from land to water. The stems can grow up to 2 meters long and protrude a few decimetres above the water. Red stem grows particularly well in shallow, warm and nutrient-rich waters. The plant usually roots in shallow riparian zones, but free-floating stems without roots can also survive in nutrient-rich deep water. Red stem is originally from South America.

Myriophyllum was imported for trade in pond and aquarium plants. The plants come into nature because people throw away excess plants in public waters, after which they can spread further.

A better image for your stereo microscope

In compound microscopes, an illumination parallel to the optical axis is the standard. A lot of hardware is implemented to ensure this axial illumination: Center-adjustable Field and Aperture diaphragm, centerable light rings for Phase contrast and Darkfield for transmitted light, center-adjustable objectives and/or centerable rotatable stages in Polarization microscopes. With all these microscopes we are working on 2-dimensional samples.

In stereo microscopy, a 3D image from a 3-dimensional sample is our ambition. Different viewing angles for both eyes create different images on the retina of the left and the right eye. Our brain is going to process both images. This concept is best comprehensible in the Greenough construction of a traditional stereo microscope: two complete separate beam paths from objective to the eyes, mounted in a relative angle of 11°-16°. But even in the modern, more flexible CMO (Central Main Objective) concept a different viewing angle is realized.

Greenough type                       CMO (Galilean) type 

Desmids - Beautiful single celled algae

There are many different types of algae, differing in both size, shape, color, habitat and more. Some types are multicellular and very large like seaweed, some are microscopic and colonial like Eudorina, while others consist of only a single cell. Some of these are called desmids (desmidiales).

Desmids are highly symmetrical unicellular green algae which can take on many different shapes depending on the specific species. The desmids also vary in size between species, the smallest being only a couple of microns and the largest reaching a size of several hundreds of microns and are visible with the naked eye. Desmids are most commonly found in freshwater where several thousand species can be found.