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R Martin

Publications and source records attributed to R Martin.

At least 685 records · Page 38Linked to original sources
PubMed1978

Effects of 8-methoxypsoralen plus 365 nm UVA light on Candida albicans cells. An electron microscopic study.

Candida (C) albicans cells were exposed to 8-Methoxypsoralen (8-MOP) concentrations of 1.0 microgram/ml and 10.0 microgram/ml medium and irradiated with 365 nm light. The amount of energy emitted was 4.8 J/cm2. Two divergent types of cell damage occured concerning yeast cell cytoplasm and cell wall. Two hours after exposure cytoplasmic changes involving mitochondria, which showed irregularities in shape, blurred appearance or loss of mitochondrial cristae and outer membrane were seen. The number of vacuoles was increased. The cytoplasm showed large electron transparent areas, the cytoplasmic membrane disappeared in some areas completely. Nucleus and nuclear envelope usually remained intact in early stages. 24h after exposure conspicuous cell wall alterations were observed in addition to cytoplasmic changes. Newly produced cell wall material formed ball-like protrusions or was adherent sickle-shaped to the cell wall. The investigations strongly suggest that the results found after 8-MOP-UVA treatment of C. albicans cells can not be interpreted in the sense of a general cytotoxic effect. Apparently it takes the form of a combination of events involving regressive and progressive alterations.

Candida albicans↗
PubMed1978

Amebic peritonitis following rupture of an amebic liver abscess. Successful treatment of two patients.

We present two successfully treated cases of amebic peritonitis. Acute peritonitis secondary to intra-abdominal rupture of an amebic liver abscess is an infrequent but serious complication of invasive amebiasis. Its diagnosis should be considered in anyone with a suspected liver abscess, jaundice, or diarrhea in whom peritonitis develops. This diagnosis should be further suggested in the United States if the patient is a male and is of Mexican origin in areas where this racial group constitutes the majority of cases of amebic disease. Use of radioisotope liver scans and the demonstration of serum precipitins to Endamoeba histolytica may provide rapid evidence of invasive disease, although surgical intervention is often necessary to make a specific diagnosis. Emetine hydrochloride alone or followed by metronidazole combined with surgical drainage is the current treatment for amebic peritonitis.

Adult↗
PubMed1978

Pituitary somatotrophs contain [Met]enkephalin-like immunoreactivity.

Serial sections from epoxy resin-embedded rat anterior pituitaries were sequentially immunostained for endorphin, [Met]enkephalin, and growth hormone, respectively. We found that [Met]enkephalin immunoreactivity was confined to the growth hormone producing cells. Corticotropin/endorphin cells in the anterior pituitary from both normal and adrenalectomized rats did not contain any [Met]enkephalin immunoreactivity. When anterior pituitary cells were maintained in monolayer culture for 10 days, [Met]enkephalin immunoreactivity was still located in the growth hormone-producing cells although the staining was weaker than in the somatotrophs in pituitary tissue fixed immediately after death of the animals. This suggested that somatotrophs synthesize [Met]enkephalin. However, this cannot be proved conclusively until biosynthesis experiments have been performed. The following conclusions were drawn from these findings. (i) Anterior pituitary [Met]enkephalin is not an extraction artifact derived from beta-endorphin with which it shares the NH2-terminal pentapeptide sequence. (ii) In the anterior pituitary, beta-endorphin is not the precursor to [Met]enkephalin. [Met]Enkephalin in somatotrophs may be of brain origin and in the somatotrophs may be bound to intracellllar receptors as has been shown for luteotropin releasing hormone in gonadotropic cells.

Adrenalectomy↗
PubMed1978

Carbon substrate utilization studies of some cultures of Alcaligenes denitrificans, Alcaligenes faecalis, and Alcaligenes odorans isolated from clinical specimens.

One hundred and sixty-two cultures of Alcaligenes species (A. denitrificans, A. faecalis, and A. odorans) of clinical origin were characterized by routine diagnostic and carbon substrate utilization techniques. The microorganisms were tested for their ability to utilize a total of 188 substrates. Substrate utilization was assayed by (i) growth stimulation and (ii) substrate alkalinization. The A. denitrificans and A. odorans cultures had unique substrate utilization profiles for each species. The A. faecalis isolates were redefined by colonial morphology into two biotypes: (i) biotype I, morphologically and biochemically similar to the A. denitrificans cultures and (ii) biotype II, morphologically similar to the A. odorans cultures.

Alcaligenes↗
PubMed1978

Granules and Golgi vesicles with differential reactivity to ACTH antiserum in the corticotroph of the rat anterior pituitary.

Slices of unembedded rat anterior pituitaries, fixed with a periodate-lysine-paraformaldehyde (PLP) fixative, were incubated with guinea pig antiserum to ACTH and stained with a peroxidase-conjugated IgG fraction of anti-guinea pig gamma-globulin serum from rabbits. The fine structure of the stained cells was identical to that of the ACTH-secreting cell, as described by Siperstein and coworkers. Immunoreactive granules were mainly located at the periphery of the cell. Numerous granules of the inner cytoplasm and also the Golgi complex were nonreactive to the antiserum. The differential labeling for granules and Golgi apparatus peptide.

Acid Phosphatase↗
PubMed1978

[Pulse cytophotometrical investigations about the resistance of DNA against acid hydrolysis influenced by ageing and cortisol (author's transl)].

The resistance of nuclear chromatin against acid hydrolysis with hydrochloric acid was studied in cell nuclei of different organs from young and old rats and after application of cortisol. Suspensions of cell nuclei from liver, spleen, kidney, heart muscle and mucosa from small intestine were stained with ethidium bromide without and after hydrolysis. The relative fluorescence intensity (FI) of every pair was measured by flow through cytophotometry. Always the FI of the diploid peaks of the hydrolysed samples was diminished. The resistance against hydrolysis was greater in old animals than in young. After application of cortisol in vivo in all organs, except in the liver, the resistance against hydrolysis was increased. Only the nuclei of liver from old animals showed a diminution of resistance after cortisol. It is assumed, that the greater resistance in age is due to the diminished functional ability of the nuclear chromatin. In the most organs, the inhibitory activity of cortisol to the cell metabolism is known, only in the liver cell it stimulates the synthesis of RNA and protein. This is in agreement with our findings.

Aging↗
PubMed1978

[Multiple "granulomas" of unknown origin; a clinical case].

A case of multiple mandibular periapical radiolucencies (granuloma) with unknown etiology is presented. A connection with herpes zoster, which formerly had occurred in the same area could not be found. Several theories are discussed, however none of them seem to fit the case inspite of thorough examination.

Dental Pulp↗
PubMed1978

Ultrastructural investigations of the formation of Candida albicans germ tubes and septa.

Germ tubes, blastospores and pseudomycelia of Candida albicans were studied under the electron microscope. Both germ tube and blastospore formation begin with comparable changes in the cell wall of the mother cell. The major part of the germ tube wall consists of the fourth of the five layers forming the C. albicans cell wall. Germ tubes are precursors of mycelia which can ramify. Septa and septal pores can be demonstrated in later phases. Pseudomycelia can be clearly discerned by means of transmission electron microscopy.

Candida albicans↗
PubMed1978

Effects of 8-methoxypsoralen plus 365 nm UVA light on Candida albicans cells. An electron microscopic study.

Candida (C.) albicans cells were exposed to 8-Methoxypsoralen (8-MOP) concentrations of 1.0 microgram/ml and 10.0 micrograms/ml medium and irradiated with 365 nm light. The amount of energy emitted was 4.8 J/cm2. Two divergent types of cell damage occured concerning yeast cell cytoplasm and cell wall. Two hours after exposure cytoplasmic changes involving mitochondria, which showed irregularities in shape, blurred appearance or loss of mitochondrial cristae and outer membrane were seen. The number of vacuoles was increased. The cytoplasm showed large electron transparent areas, the cytoplasmic membrane disappeared in some areas completely. Nucleus and nuclear envelope usually remained intact in early stages. 24 h after exposure conspicuous cell wall alterations were observed in addition to cytoplasmic changes. Newly produced cell wall material formed ball-like protrusions or was adherent sickle-shaped to the cell wall. The investigations strongly suggest that the results found after 8-MOP-UVA treatment of C. albicans cells can not be interpreted in the sense of a general cytotoxic effect. Apparently it takes the form of a combination of events involving regressive and progressive alterations.

Candida albicans↗
PubMed1977

Effect of vicarious punishment on stuttering frequency.

This investigation explored the effect of vicarious response-contingent stimulation on the frequency of stuttering. Twenty adult stutterers spoke for 20 minutes, then observed a speaker on a videotape for 10 minutes, and then spoke for an additional 20 minutes. In one condition the speaker on the videotape was a severe stutterer who experienced a dramatic reduction in stuttering under a contingent time-out procedure. In a second condition, the videotape speaker was a severe stutterer who received no experimental manipulations. In the third condition, the videotape speaker was a normal talker who received no experimental manipulations. All subjects participated in all three conditions. Twenty of the stutterers experienced a significant decrease in stuttering as a result of watching the videotape model who received contingent time-out. The subjects did not exhibit significant changes in stuttering after watching the severe stutterer who received no treatment or the normal talker.

Adult↗
PubMed1977

125I therapy.

Explore the source record for details and available documents.

Female↗
PubMed1977

[RNA metabolism and ageing (author's transl)].

The labelling behaviour of RNA fractions in rat liver after application of 32P-orthophosphate and 14C-orotate in vivo in young (3-5 months) and old animals (20 months) was presented. Whereas the tracer incorporation in old animals 60 minutes after 32P-application seems to be decreased we observed increased specific activities of nuclear RNA 30 and 60 minutes after application of 14C-orotate i.p. - Measuring of RNA synthesis in isolated cell nuclei after in vivo stimulation by cortisol (2 mg/100 g body weight) showed a stronger and longer continued stimulation in young animals as in old both in the Mn++ system and in the Mg++ system. When we compared the young with the old controls the rate of synthesis was increased in the old controls. The results support observations on changed regulations of the transcription of genetic informations in the age.

Age Factors↗