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P Beers

Publications and source records attributed to P Beers.

8 recordsLinked to original sources
PubMed1999

Note: evaluation of selective media for the enumeration of Bifidobacterium sp. in milk.

Pure cultures of three species of bifidobacteria (Bifidobacterium longum, Bif. adolescentis and Bif. bifidum), Lactobacillus acidophilus and a mixed culture of Lact. delbrueckii subsp. bulgaricus and Streptococcus salivarius subsp. thermophilus were each enumerated on two differential media and six selective media for the enumeration of bifidobacteria. The appearance of the colonies on the differential media was as expected but when mixed cultures were present, it proved extremely difficult to distinguish one species from another. Of the selective media, AMC, RMS, NPNL and BL-OG performed well in that they gave good recoveries of bifidobacteria and were inhibitory to the growth of Lact. delbrueckii subsp. bulgaricus, Strep. salivarius subsp. thermophilus and Lact. acidophilus. However, of these four media, AMC was most convenient as it is based on a commercially available medium, whereas the others must be made up from individual constituents. The AMC agar is thus a good choice for the routine enumeration of bifidobacteria from mixed cultures.

Animals↗
PubMed1982

Hormonal variations during sleep in men with erectile dysfunction and normal controls.

Five physically healthy young males suffering from erectile impotence and five normal controls of similar age are the subjects of this preliminary report. All were studied in the sleep laboratory during 3 to 5 nights with the last two devoted to sequential hormonal sampling by means of an indwelling venous catheter. Electroencephalogram, eye movements, and penile tumescence were monitored continually through the night. Plasma LH, FSH, and testosterone were measured every 20 minutes by radioimmunoassay. There were no differences between the patients with erectile impotence and normal controls in all sleep parameters investigated, including mean tumescent time, time in simultaneous REM and tumescence, and number of full and partial tumescent episodes. Marked fluctuations in plasma LH, FSH, and testosterone were observed during sleep without differences noted between the two groups. Mean plasma LH, but not FSH or testosterone, was significantly lower in the impotent men. There were no significant differences in mean plasma gonadotrophins and testosterone between tumescent episodes and nontumescent periods in either group. A significant relation was found in normals, but not in the men with erectile dysfunction, between the occurrence of REM sleep and abrupt elevations in testosterone. Testosterone levels during REM sleep with tumescence were also consistently higher than during the condition of non-REM without tumescence in the normal, but not in the impotent, group.

Adult↗
PubMed1980

Leukocyte migration enhancement as an indicator of immunologic enhancement. I. Pregnancy.

Leukocyte migration studies with amniotic fluid (AF) were performed in 47 pregnant women and 24 control patients. Previous reports about the enhancing effect of AF on leukocyte migration during pregnancy were confirmed (p less than 0.003). No enhancing effect was observed with first-trimester leukocytes. Maximal enhancement occurred during the second trimester (p less than 0.0001). It decreased during the third trimester (p less than 0.01) and lost significance in the postpartum period (p less than 0.072). Fifteen pregnant and control patients were investigated with autologous plasma. Leukocyte migration enhancement (LME) was significant with pregnancy plasma (PL) (p less than 0.03). Again LME was the largest during the second trimester (p less than 0.006). It is concluded that an immunologically active factor is present in AF and PL which in term induces the enhancing activity of a predetermined effector cell subgroup. This process is absent in conjunction with male leukocytes and is lacking in the majority of patients with toxemia of pregnancy.

Amniotic Fluid↗
PubMed1980

Leukocyte migration enhancement as an indicator of immunologic enhancement. III. Common denominators of pregnancy and malignancy.

Leukocyte migration enhancement (LME), a common denominator of pregnancy and malignancy, was investigated in order to determine the immunologic factors and processes involved in this in vitro assay. Reproducibility of results was confirmed by parallel investigations of single patients in an independent laboratory. Preliminary evidence also suggests that the phenomenon of LME is observable not only with the leukocyte migration assay, as performed in the present study, but also with the "indirect" migration inhibitory factor (MIF) assay. Highly significant correlation between results obtained with plasma (PL) and amniotic fluid (AF) was observed (p less than 0.00089). No significant correlation between LME and IgG concentrations as well as complement (C3) concentrations in AF and PL could be detected. C3 concentrations correlated significantly to gravity (p less than 0.007) and parity (p less than 0.003). No immune complexes were detected in either AF or PL samples. An unspecific protein effect as the cause of LME was ruled out in showing no significant correlation between LME and protein concentrations of AF and PL. A highly significant correlation between antigen concentration in PL and migration area was demonstrated (p less than 0.00001). It is suggested that leukocyte migration inhibition (LMI) represents a state of antigen excess, while LME represents antibody excess. Through selective removal of the IgG immunoglobulins LME could be converted into LMI, indicating an IgG subfraction as the responsible immunoglobulin in the phenomenon of LME.

Amniotic Fluid↗
PubMed1980

Leukocyte migration enhancement as an indicator of immunologic enhancement. II. Malignancy.

Leukocyte migration studies were performed on 19 cancer patients and 24 control subjects. Amniotic fluid (AF) as well as autologous plasma (PL) were investigated. No difference in the migration pattern between patients and control subjects was observed with AF, but cancer patients showed significant leukocyte migration enhancement (LME) with PL when compared to control subjects (p less than 0.04). Among 18 cancer patients with persistent disease only three did not show significant LME. All three represented specifically immunodepressed states. None of the untreated group of cancer patients failed to show LME with autologous PL. It is concluded that, as in pregnancy, an immunologic active factor is present in PL of cancer patients which induces a specific subpopulation of leukocytes and thereby LME. The possible mechanism of activation is briefly discussed. Through the detection of LME leukocyte migration may become of importance for the early detection of malignancy and monitoring of treatment success.

Adenocarcinoma↗
PubMedDate not supplied

Pituitary-gonadal function during sleep in men with erectile impotence and normal controls.

Studies of pituitary-gonadal function in men with erectile disorders have provided conflicting findings. This study compares blood LH and testosterone during sleep in 17 physically healthy men with erectile impotence and 12 matched normal controls, and relates hormonal variations to stages of sleep and penile tumescence. Subjects, aged 23-36 were studied in a sleep laboratory for 3-6 nights with the last two nights devoted to sequential blood sampling every 20 minutes. Five men had never been able to achieve intercourse (primary impotent group) and 12 suffered from a life-long history of intermittent erectile failures (secondary-impotent group). There were no significant differences in sleep duration and REM time among the impotent groups and normal controls. Primary-impotent men showed half as many full tumescent episodes as secondary-impotent men and controls, and spent significantly less time above 80% of full tumescence. The secondary-impotent group did not differ in nocturnal penile tumescent measures from controls. There was a pattern of irregularly occurring fluctuations in plasma LH and testosterone with no differences among groups in frequency and amount of peak hormonal increases. Normal subjects had significantly higher mean testosterone concentrations during REM sleep than during other sleep stages, and during full tumescence than during partial and nontumescent periods. A direct causal relation between REM-related activity and circulating testosterone was not supported by the observation that the hormonal levels during REM sleep and during full tumescence did not differ statistically from the levels measured during adjacent time periods. As with normal subjects, the secondary-impotent group exhibited higher testosterone levels during REM sleep and full tumescence; by contrast, the primary-impotent group did not show significant hormonal differences across stages of sleep and tumescent/ nontumescent periods. These data are discussed with respect to the possible existence of subgroups of impotent men without known organic pathology than may be characterized by psychophysiologic and endocrine differences during sleep.

Adult↗