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J Kucera

Publications and source records attributed to J Kucera.

At least 217 records · Page 12Linked to original sources

Histochemical study of an unusual cat intrafusal muscle fiber.

A cat tenuissimus muscle spindle that contained two long chain intrafusal fibers in its distal pole is described. One of the fibers (lc1) had a histochemical profile (ATPase, NADH-TR, ChE reactions) of the kind which is characteristic for long chain fibers. The other fiber (lc2) consisted of two separate segments. The inner lc2 segment included the sensory equatorial region and was histochemically normal. The outer lc2 segment carried a motor plate, and did not stain for NADH-TR in the same way as the inner lc2 segment and the lc1 fiber. It is suggested that the unusual enzyme staining properties of the outer lc2 segment stemmed from its lack of sensory innervation, a situation which may have permitted the full expression of influences mediated by its motor nerve supply.

Adenosine Triphosphatases↗

The occurrence of "mixed" nuclear bag intrafusal fibers in the cat muscle spindle.

A total of 147 muscle spindles was studied histochemically in serial transverse sections of 42 cat tenuissimus muscle specimens. Nuclear bag1, nuclear bag2 and nuclear chain intrafusal muscle fibers were distinguished by the differential staining resulting from the reactions for myosin adenosine 5'-triphosphatase and nicotinamide adenine dinucleotide tetrazolium reductase. The majority of intrafusal fibers were of the same histochemical type at both fiber poles. However, seven muscle spindles contained one nuclear bag fiber each that presented as a bag1 in one pole and as a bag2 in the other pole. These "mixed" nuclear bag fibers were found in spindles that also contained at least one bag1 and one bag2 fiber of equivalent histochemical presentation in both fiber poles. The "mixed" bag fibers displayed differences of apparent fiber diameter and relative polar length between the two fiber poles. The motor innervation pattern, as revealed by staining for cholinesterase, was also dissimilar between the two poles of "mixed" bag fibers. The study indicates that the spindle equatorial region may in some instances serve as a boundary between two morphologically and histochemically different poles of the same intrafusal fiber.

Acetylcholinesterase↗

Blood parasites of birds in Central Europe. 1. Survey of literature. The incidence in domestic birds and general remarks to the incidence in wild birds.

This paper constitutes an introduction to the forthcoming series of publications summing up the present store of knowledge on the incidence and ecology of avian haematozoa in Central Europe. The paper contains bibliography dealing with the incidence of these parasites in the region studied. The problem of the incidence of blood parasites in domestic birds is discussed in detail. The incidence of blood parasites in wild birds is only briefly outlined as it is to be treated in detail in forthcoming papers.

Animal Population Groups↗

Blood parasites of birds in Central Europe. 3. Plasmodium and Haemoproteus.

The present paper is the third in the series on blood parasites of birds in Central Europe. It is devoted to the genera Plasmodium and Haemoproteus. Plasmodium has been found in 11.3% of birds belonging to 54 species, most abundant being in Galliformes and Columbiformes. On the other hand, this parasite seems to be absent in Anseriformes, Falconiformes, Hirundinidae and Sturnidae in Central Europe. Haemoproteus has been encountered in the studied region in 11.8% of birds belonging to 85 species. It is most abundant in Falconiformes, Strigiformes, Hirundinidae, Emberizidae, Fringillidae, Muscicapidae, Paridae and Turdidae, but it has not been encountered in Anseriformes. The paper also discusses the dependence of the incidence of these parasites on migratory ability of their hosts and on the nest ecology of birds. Moreover, an ecological outline is given of the representatives of the genera Plasmodium and Haemoproteus in birds in Central Europe, mainly on the basis of the ecological model of avian malaria after Beaudoin et al. (1971).

Animals↗

[Drugs and foods].

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Drug-Related Side Effects and Adverse Reactions↗

Histochemical study of long nuclear chain fibers in the cat muscle spindle.

Cat intrafusal muscle fibers were examined histochemically in serial transverse sections of tenuissimus muscle spindles. The "myofibrillar" adenosine triphosphatase staining reaction was used to recognize the nuclear bag and the nuclear chain fibers in 309 spindle poles. Poles of 40 nuclear chain fibers extended for 1,000 micrometer or more beyond the termination of the spindle capsule. These long chain fibers stained less intensely for nicotinamide adenine dinucleotide tetrazolium reductase (NADH-TR) than the typical chain fibers of shorter polar length. In sections stained for cholinesterases (ChE), the extracapsular regions of most long chain fibers displayed one or two short, dense "plate"-type ChE deposits, which may represent the terminals of skeleto-fusimotor axons. In addition, about one-third of the long chain fibers displayed one or more thinner and smaller areas of ChE activity, possibly corresponding to the endings of fusimotor axons. The overall ChE staining pattern of the typical chain fibers was unlike that of the long chains. However, some of the shorter nuclear chain fibers resembled long chain fibers with the NADH-TR reaction, even though their ChE "plates" were located intracapsularly. It is concluded that nuclear chain fibers in the cat spindle form a class of intrafusal fibers with heterogeneous histochemical properties, and that the long chain fibers represent one fiber subtype.

Adenosine Triphosphatases↗

Myofibrillar ATPase activity of intrafusal fibers in chronically de-afferented rat muscle spindles.

Dorsal root ganglia L4, L5 were removed to accomplish long-term (1 year) de-afferentation of the rat soleus muscle. Muscle spindles in the muscles deprived of sensory innervation were morphologically and histochemically abnormal. The spindle periaxial fluid space was greatly diminished with a thicker capsular investment. De-afferented intrafusal muscle fibers lacked either "nuclear bags" "nuclear chains" at their midlengths. The intracapsular myofibrillar ATPase staining pattern of de-afferented nuclear bag fibers resembled that which the bag fibers normally display in their extracapsular regions. These abnormalities are discussed with respect to the regulatory functions of spindle sensory and motor nerves.

Adenosine Triphosphatases↗

Motor innervation of the cat muscle spindle studied by the cholinesterase technique.

Muscle spindles were traced in serial transverse sections of cat tenuissimus muscles. "Myofibrillar" adenosine triphosphatase staining reaction was used to identify nuclear bag1, nuclear bag2 and nuclear chain intrafusal muscle fibers. Typical chain fibers and long chain fibers were distinguished, the latter extending for more than 1,000 micron beyong the termination of the spindle capsule. Simple "rim" and more elaborate "plate" deposits were demonstrated histochemically along the poles of the typical chain fibers in staining for cholinesterases. They were considered to correspond, respectively, to the trail and plate motor nerve terminals. Most long chain fibers and the majority of nuclear bag fibers had their motor innervation limitd to "plate"-type endings. In addition, faint diffuse cholinesterase staining occurred along the spindle capsule and the surface of some intrafusal fibers. These histochemical observations are discussed with regard to the current concepts concerning the morphological and functional organization of the motor innervation of the cat muscle spindle.

Animals↗