Search PubMed⌕ Search

Biomedical subjects

L Kass

Publications and source records attributed to L Kass.

At least 55 records · Page 3Linked to original sources
PubMed1988

Cytochemistry and immunocytochemistry in bone marrow examination: contemporary techniques for the diagnosis of acute leukemia and myelodysplastic syndromes. A combined approach.

Although the cytologic type of acute leukemia can often be suspected on the basis of conventional panoptically stained specimens, it is important to document as precisely as possible the type of leukemia before the institution of specific treatment. At the present time, this documentation can usually be achieved with cytochemical stains that demonstrate enzymes and/or metabolites of diagnostic value. Additional immunocytochemical stains can often identify cells of ambiguous origin on the basis of cell-specific properties such as antigens. Immunophenotyping has proven to be of considerable value in the diagnosis and classification of ALL. At present, the practicality of surface antigen phenotyping in ANLL remains to be documented. The identification of hybrid leukemia is clearly facilitated with immunologic markers. Present criteria for the diagnosis of myelodysplastic syndrome do not include immunophenotyping. By use of a combination of morphologic criteria, traditional cytochemical stains, and immunocytochemical techniques, it is possible to establish the cell of origin in the large majority of cases of acute leukemia. Those rare cases in which the usual patterns of reactivity do not occur provide additional stimuli to develop new cytochemical and immunologic methods that will help to establish the origin of the leukemic blast.

Bone Marrow↗
PubMed1987

Investigations on urinary bladder reinnervation. Historical perspective and review.

Although nerve crossover surgery to bypass a spinal cord lesion and recentralize the decentralized bladder was first conceptualized in 1907, surprisingly few studies concerning this goal have been reported since. In addition to direct implantation of nerves into the detrusor, the studies reviewed have investigated the crossover of mixed roots (with and without nerve grafts), dorsal roots, ventral roots, pelvic, obturator and hypogastric nerves both in animal models, in human cadavers, and in human patients. Restoration of the micturition reflex through the use of nonsacral nerves has been achieved in cats. In addition, we have shown that the axons of a suprasacral mixed root (L7) when anastomosed to a sacral mixed root (S1) via a nerve graft can regenerate and recentralize the unilaterally decentralized bladder in the cat. The return of the micturition reflex after reconstruction of severed pelvic nerves has been documented, while the results of obstruction or hypogastric crossover have given diminished returns of bladder function. The direct implantation of nerves into the detrusor has not resulted in restoration of function. In addition, return of useful bladder function in humans after nerve crossover surgery has not been predictable. In part, present inability to achieve restoration of urinary bladder function may be a consequence of the complexity of micturition reflex organization and the inability to use techniques in humans that have given success in animals. Although, some of the technical aspects of nerve crossover surgery to bypass a spinal cord injury and restore functional micturition in those with neurogenic bladder dysfunction have been elucidated, further work is required to develop techniques that will enhance appropriate axonal regeneration to achieve reinnervation and return of useful function. Indeed, restoration of function may be limited by current microsurgical methodologies. Studies directed at understanding the neuropathophysiology of nerve injury and nerve surgery may be more fruitful in identifying factors than can be manipulated to achieve consistent return of useful function. In general, however, the results of the animal and human studies surveyed may be viewed with cautious optimism.

Animals↗
PubMed1987

Nerve crossover techniques for urinary bladder reinnervation: animal and human cadaver studies.

Interruption of spinal pathways integrating central and peripheral bladder control mechanisms will result in neurogenic bladder dysfunction. If central pathways could be restored to the decentralized bladder through a microneural reconstructive technique a return of useful function might be achieved. This anatomical study describes the nerve crossover techniques used in human cadaver dissections for connecting intercostal nerves to sacral roots intraspinally. The techniques were modified from and compared to similar procedures used in an animal model where adjacent extradural roots were connected through a nerve graft. We have shown previously that the unilaterally decentralized bladder of the cat can be recentralized after a nerve crossover procedure. If additional laboratory studies can document return of useful bladder function we anticipate that selected patients may benefit from similar nerve crossover techniques to bypass a spinal cord lesion to recentralize the bladder.

Animals↗
PubMed1987

Identification of neutrophils with an oxazine dye.

Used in an alkaline-buffered solution on fixed smears of bone marrow or peripheral blood, the oxazine dye CI basic blue 141 preferentially stained neutrophil granules a bright crimson red. In neutrophils, these granules were numerous, whereas in bands, only a few granules were seen. In other types of blood or bone marrow cells, crimson red granules of the type described were not found to an appreciable degree. Used as a tinctorial stain, this dye may be useful in the study of disorders of neutrophil function and neutrophil physiologic characteristics, as well as in the identification of neutrophils and their distinction from other types of cells.

Absorption↗
PubMed1987

C. I. acid red 52: a new stain for cells of granulocytic origin.

Using the xanthene dye C.I. acid red 52 (C.I. 45100) as a single agent stain applied to coverslip preparations of blood and bone marrow, primary and secondary granules in cells of neutrophilic origin stained brilliant pink. In eosinophils, granules stained dark red. In leukemic myeloblasts that also stained with Sudan black B and demonstrated myeloperoxidase and specific esterase activity, a few bright red staining granules were visualized with acid red 52. In some leukemic promyelocytes, Auer rods stained bright red. In leukemic lymphoblasts, no red granules were seen. Of a wide variety of dyes tested so far, acid red 52 is the most sensitive stain for primary and secondary granules of granulocytes in blood and bone marrow.

Bone Marrow↗
PubMed1986

Urinary bladder reinnervation.

The ability of mixed spinal nerve roots to regenerate and reinnervate the urinary bladder was examined in young adult female cats. Using microsurgical technique, a unilateral extradural spinal nerve root anastomosis of a lumbar (L7) to a sacral root (S1) either with or without a nerve graft was performed. Remaining ipsilateral sacral roots were transected. The contralateral normal sacral roots remained intact and allowed the animals adequate urination during the period necessary for axonal regeneration. At the time of restudy seven months later, stimulation of the anastomosed nerve root proximal to the anastomosis (isolated from the spinal cord) elicited a bladder contraction. Significant lumbar axonal regeneration was substantiated by compound action potentials recorded across the anastomosis. In addition, redirection of axons from a lumbar to a sacral distribution was demonstrated. The contralateral normal sacral roots provided control cystometric and electrophysiological data against which responses from the previously anastomosed nerve roots were compared. In conclusion, significant bladder reinnervation can occur after an anastomosis of a lumbar and sacral root with or without a nerve graft. This technique, or variations thereof, may have a clinical role in selected patients with neurogenic bladder dysfunction to reinnervate the bladder and restore central control.

Animals↗
PubMed1986

Synacril black AN. A new stain for normal and abnormal human megakaryocytes.

After methanol fixation and ribonuclease digestion, normal and abnormal human megakaryocytes displayed intense red-purple coloration of the cytoplasm and dark brown nuclei when stained with the cationic textile dye Synacril black AN. In other marrow cells, cytoplasm stained cream color or pale blue in the case of eosinophils. In eosinophils, granules stained pink. As a complement to more complex immunologic technics, staining of megakaryocytes with Synacril black AN may represent a rapid screening method for identification of these cells.

Bone Marrow↗
PubMed1986

Identification of normal and leukemic granulocytic cells with merocyanine 540.

After fixation in a modified Bouin's solution, the acid dye merocyanine 540 stained granules in granulocytic cells intensely. In immature granulocytes, such as promyelocytes and myelocytes, granules stained pink to violet. In some leukemic myeloblasts, promyelocytes and monocytes, granules also stained deep pink to violet. In more mature granulocytes, such as metamyelocytes, bands, and neutrophils, granules stained bright red to orange. In eosinophils and basophils, granules stained deep red. Granules of the type described were not visualized in normal plasma cells, lymphocytes, monocytes, or megakaryocytes. In normoblasts, cytoplasm stained diffusely red. Cytoplasmic staining in erythroblasts became darker as the cell matured, probably reflecting hemoglobin content. Used as a single agent stain, merocyanine 540 may be useful in distinguishing normal and leukemic granulocytic cells from other types of blood cells.

Bone Marrow↗
PubMed1985

Lycramine brilliant blue JL: a new stain for human megakaryocytes.

Using the acrylic textile dye Lycramine brilliant blue JL, mature and immature megakaryocytes from human bone marrow specimens stained metachromatically bright lavender. This coloration was not observed in other types of bone marrow cells. After digestion with either diastase or ribonuclease, subsequent staining of marrow specimens did not reveal a significant diminution of the intensity of staining of megakaryocytes. However, after incubation with hyaluronidase followed by staining with Lycramine brilliant blue JL, staining of megakaryocyte cytoplasm was either imperceptible or very pale blue. Accordingly, at least one of the substances responsible for the staining reaction is acid mucopolysaccharide in the cytoplasm of megakaryocytes. With further experience and comparison with established immunologic and cytochemical techniques, staining of megakaryocytes with Lycramine brilliant blue JL may be a useful addition to the cytochemistry of blood and bone marrow cells.

Acrylates↗
PubMed1985

Identification of human megakaryocytes with rhodanile blue.

Using the oxazine dye rhodanile blue, large typical megakaryocytes and small megakaryocytes (micromegakaryocytes) from the bone marrows of normal persons, and from patients with a variety of preleukemic disorders, acute lymphoblastic and nonlymphoblastic leukemia, chronic granulocytic leukemia, and idiopathic thrombocytopenic purpura as an example of nonmalignant but abnormal megakaryocytopoiesis, showed intense pink staining of the cytoplasm. This pink metachromasia was not obliterated by prior digestion with either diastase or ribonuclease, but was markedly diminished or obliterated by preincubation with hyaluronidase, suggesting that the stain may detect a high content of acid mucopolysaccharides in megakaryocytes. Since the stain is simple, direct, and reproducible, it may represent a useful addition to the cytochemistry of megakaryocytes and complement the more complex immunologic techniques available currently.

Bone Marrow Examination↗
PubMed1984

Efferent neurotransmission of circadian rhythms in Limulus lateral eye. I. Octopamine-induced increases in retinal sensitivity.

Octopamine increases the sensitivity of the Limulus lateral eye in situ when injected beneath the cornea during the day. The effect of octopamine is dose-dependent with a threshold concentration of about 0.1 microM injected at 1 microliter/min for 15 min. Injection of 40 microM octopamine increases lateral eye sensitivity to approximately 70% of the nighttime level normally caused by the efferent output of a circadian clock. Injections of octopamine analogues and other candidate neurotransmitters indicate that the postsynaptic receptor mediating the increase of retinal sensitivity is relatively specific for the structure of octopamine. The postsynaptic receptor is tentatively classified as a type 2B octopamine receptor (Evans, P. D. (1981) J. Physiol. (Lond.) 318: 99-122). Clozapine suppresses the effects of both exogenous octopamine and the endogenous efferent neurotransmitter. Together with the results from Barlow et al. (Barlow, R. B., Jr., S. J. Bolanowski, Jr., and M. L. Brachman (1977) Science 197: 86-89) and Battelle et al. (Batelle, B. -A., J. A. Evans, and S. C. Chamberlain (1982) Science 216: 1250-1252) our study leads to the following conclusion: retinal efferents, driven by a circadian clock in Limulus brain, release octopamine that increases visual sensitivity.

Animals↗
PubMed1983

Presynaptic uptake blockade hypothesis for LSD action at the lateral inhibitory synapse in Limulus.

We investigated the action of LSD at the putative indoleaminergic lateral inhibitory synapse in the lateral eye of Limulus polyphemus. We recorded extracellular and intracellular voltage responses from eccentric cells while producing inhibition either by light or by antidromic stimulation of the optic nerve in the presence of LSD, serotonin (5-HT), chlorimipramine, or a bathing medium whose high Mg++ and low Ca++ concentrations partially or completely blocked synaptic transmission. We found (a) light-evoked and antidromically stimulated lateral inhibition is enhanced during superfusion of low (1-5 microM) concentrations of LSD and suppressed by higher (5-20 microM) concentrations; (b) these actions of LSD are markedly reduced by bathing the retina in a medium high in Mg++ and low in Ca++; (c) very low concentrations of chlorimipramine, a putative uptake blocker of serotonin, appear to mimic actions of LSD both on eccentric cell firing rate and on lateral inhibition; (d) superfused 5-HT depresses lateral inhibition at all superthreshold concentrations (0.1-25 microM). These results suggest that LSD's action may require an intact inhibitory transmitter release and postsynaptic response mechanism, whereas serotonin exerts a direct postsynaptic effect. We propose that LSD blocks presynaptic uptake of transmitter at the lateral inhibitory synapse. The concentration dependence of LSD's action can be accounted for as follows: low concentrations partially restrict transmitter reuptake, thereby prolonging the lifetime of the transmitter in the synaptic cleft and thus increasing the magnitude and duration of postsynaptic inhibition. Higher concentrations cause more presynaptic uptake sites to be blocked; this causes accumulation of transmitter in the synaptic cleft, which causes a functional blockade of the synapse because of postsynaptic desensitization. As an alternative, we propose a hypothesis based on LSD action at presynaptic autoreceptors. Similar hypotheses can account for many aspects of LSD's action in mammalian brain.

Animals↗
PubMed1981

Staining of granulocytic cells by Chlorazol black E.

Using the trisazo dye Chlorazol black E, granules in neutrophilic granulocytes stained pale orange, gray and black. In promyelocytes, granules were mainly orange, whereas in myelocytes and metamyelocytes, mixtures of orange and black granules were seen. In neutrophils, a few orange granules were seen, and most of the granules stained gray and black. In eosinophils and basophils, granules stained orange. In monocytes, a few black and gray staining granules were seen. In lymphocytes, as well as other marrow cells like erythroblasts and megakaryocytes, granules were not visualized. Chlorazol black E may be a useful addition to the cytochemistry of blood cells, particularly in distinguishing cells of granulocytic origin from other cell types.

Azo Compounds↗
PubMed1980

Niagara sky blue 6B--a new stain for granulocytic cells.

Using an acidified solution of Niagara sky blue 6B, granules in mature granulocytic cells from peripheral blood and bone marrow stained bright blue to blue-green. Granules in immature granulocytes like myelocytes and promyelocytes stained purple. In leukemic myeloblasts and leukemic monocytes, granular-appearing structures stained purple. In leukemic lymphoblasts, purple granular structures were not visualized. As such, Niagara sky blue 6B can be used to identify granulocytic cells at all maturational stages.

Azo Compounds↗