Page 313 - parasitology for medical and clinical laboratoryprofessionals

GLOSSARY 293

Golgi complex Termed the “export complex” with unique Heartworms A heartworm is a parasitic roundworm (Diro-
proteins that seem specialized for information flow to and from filaria immitis) infecting dogs, but other canids particularly
ER (endoplasmic reticulum) and the Golgi complex. and rarely humans may be infected. The disease is spread from
Gomori stain The stain provides for a permanent stained smear host to host through the bites of mosquitoes.
that enhances detection and identification of cysts and trophozo- Helminthiases Condition of being infected by flatworms
ites where a permanent record of the protozoa is required. (platyhelminthes).
Graft rejection Immunologic destruction of transplanted Helminthology Study of parasitic and other worms.
organs or tissues that is based on both cellular and humoral Helminths A wormlike animal belonging to the phyla Platy-
(antibody-mediated) reactions. helminthes (flatworms).
Graft vs. host reaction The T-lymphocytes of the donor’s Hemaphroditic An animal or plant that possesses both male
tissues or bone marrow may recognize the recipient’s body tis- female reproductive organs.
sues as non-self and when this occurs, the transplanted bone Hematuria Presence of blood in the urine.
marrow cells attack the transplant recipient’s body. Hemiptera Several insects of the order Hemiptera pos-
Gram negative bacteria Stain that differentiates between sessing biting or sucking mouthparts and two pairs of wings.
two broad groups of bacteria. The Gram-positive organisms Hemipterans include the leafhoppers, treehoppers, cicadas,
retain the crystal violet portion of the stain while the Gram- aphids, scales, and true bugs.
negative organisms retain the red-colored counter stain com- Hemoflagellates A flagellated protozoan that inhabits the
prised of safranin. blood; most important hemoflagellates are the genera Trypano-
Granular Granular material is described as a conglomeration soma (malaria) and Leishmania.
of discrete solid, macroscopic particles giving an inconsistency Hemorrhage Literally means “bursting forth” as in the act of
to the homogeneity of the material. bleeding copious amounts.
Granulocytes White cells that arise from a myeloid stem cell, Hemorrhagic pancreatitis Pancreas inflamed to such an
and include neutrophilic segmented or polymorphonuclear extent that bleeding occurs, possibly resulting in massive,
cells, eosiniphils and basophils; neutrophilic WBC’s may en- difficult-to-control bleeding.
gulf bacterial organisms and destroy them by lytic processes; Hepatitis B Liver infection caused by the hepatitis B virus
eosinophils play a major role in the killing of parasites, particu- (HBV) that may become chronic and lead to liver failure, can-
larly for enteric nematodes as their granules contain a unique, cer, and cirrhosis.
toxic basic protein and a cationic protein. Hepatomegaly Enlargement of the liver.
Granulomatous lesions A group of inherited diseases Herbivore Grazing animals that predominantly eat grass and
where certain cells of the immune system have difficulty form- other vegetation.
ing the reactive oxygen compounds through oxidative or Hippocratic Oath Oath exacted of the students of Hip-
“respiratory burst” activity required to kill certain ingested pocrates for student physicians; historically one of the oldest
pathogens. documents outlining expectations of a professional. The oath
Gravid proglottids Gravid proglottids from tapeworms en- basically requires treatment of the sick to the best of one’s abil-
compass egg capsules and when they break free they pass out ity, preservation of patient privacy, and teaching of medicine to
in the feces and then release the egg capsules. the next generation. The oath has been modified several times
Ground itch An itching sensation caused by the penetrating from the original document.
and burrowing into the skin of larvae of hookworms Ancylos- Hirudinea Class of parasitic or predatory annelid (seg-
toma duodenale or Necator americanus. mented) worms with 34 annelids or rings around them; the
Guillain-Barre syndrome Neurological disease following common name is leech and the organism uses terminal suckers
acute infection with Campylobacter jejuni, cytomegalovirus for both attachment to its prey and for locomotion.
or Epstein-Barr virus that is rare; ascending paralysis of the Hookworm larvae The means of infectivity for hookworms
motor functions and progresses to the respiratory muscles; is through the larvae found in the soil that are able to penetrate
some residual damage may remain after disease is resolved. the skin; hookworm eggs are not infective.
Guinea worm Refers to the filarial form of Dracunculus Host Organism from which nutrients are obtained for the
medinensis. parasite, and is part of the parasite’s life cycle.
Gundi Small, stocky rodents that live in rocky deserts across Human granulocytic ehrlichiosis (HGE) Rare infec-
northern Africa as important reservoirs of leishmania. tious disease caused by a genus of bacteria that belongs to the
Ehrlichia family. The bacterium is carried and transmitted by
H certain ticks, namely the deer tick (Ixodes dammini) and the
American dog tick (Dermacentor variabilis).
Habitat Geographic location where organisms may dwell. Human hydatid disease The larval stage of the dog tape-
Hard tick The hard ticks are those that transmit the most worm Echinococcus granulosus is responsible for hydatid dis-
pathogens; these ticks have a hard shield or scutum on the ease in humans; acquired from animals through ingestion of
back and mouth parts that project from the head. The families tapeworm eggs excreted in the feces of infected dogs.
of Ixodidae, Amblyomma, Bophilus, and Dermacentor, and Human Immuno-deficiency Virus (HIV) A retrovirus
several other less important vectors are all hard ticks. that can cause acquired immunodeficiency syndrome (AIDS).