Differential regulation of vitamin D receptors in clonal populations of a chronic myelogenous leukemia cell line

RWLeu4 is a chronic myelogenous leukemia cell line that is sensitive to the antiproliferative and differentiation-inducing actions of 1alpha,25(OH)2-vitamin D3 (VD3). The JMRD3 cell line is a VD3-resistant variant of RWLeu4 that was selected by continuous passage of RWLeu4 in the presence of VD3. The isolation of a spontaneous VD3-resistant variant suggests that phenotypically different cells exist within the RWLeu4 cell population. Therefore, single-cell clones of RWLeu4 cells were isolated and characterized. Four clonal cell populations that fall into three groups differing in response to the antiproliferative and differentiation-inducing actions of VD3 were examined. Surprisingly, the extent of response of the clones to VD3 does not show a correlation with the basal level of the vitamin D receptor (VDR). RWLeu4-3 and RWLeu4-4 are the clones most sensitive to the antiproliferative actions of VD3 (ED50 approximately equal to 1 nM); however, RWLeu4-3 expresses basal levels of VDRs similar to those found in the parental cells and the RWLeu4-2 clone, while in RWLeu4-4, VD3 binding and VDR protein are below the limits of detection. Furthermore, RWLeu4-10 expresses the highest basal level of VDR protein but is relatively resistant to the antiproliferative actions of VD3 (ED50 > or = 30 nM). Like JMRD3, RWLeu4-10 is still capable of differentiating in response to VD3, as judged by the induction of biochemical processes and cell-surface antigen expression. Although VD3 treatment increases VDR protein levels and DNA-binding activity in all clones, altered DNA-protein complexes are detected in RWLeu4-4. Our results suggest that sensitivity to the antiproliferative and differentiation-inducing actions of VD3 is not dependent solely upon the level of VDR expressed, but may also require posttranslational modification of the VDR or complex interactions with other nuclear transcription factors.

Osmium-187 Enrichment in Some Plumes: Evidence for Core-Mantle Interaction?

Calculations with data for asteroidal cores indicate that Earth's outer core may have a rhenium/osmium ratio at least 20 percent greater than that of the chondritic upper mantle, potentially leading to an outer core with an osmium-187/osmium-188 ratio at least 8 percent greater than that of chondrites. Because of the much greater abundance of osmium in the outer core relative to the mantle, even a small addition of metal to a plume ascending from the D" layer would transfer the enriched isotopic signature to the mixture. Sources of certain plume-derived systems seem to have osmium-187/osmium-l88 ratios 5 to 20 percent greater than that for chondrites, consistent with the ascent of a plume from the core-mantle boundary.

Diet, body mass index, and colonic epithelial cell proliferation in a healthy population

Using 63 healthy subjects, we conducted an observational study to assess associations between colonic epithelial cell proliferation and dietary intake of selected nutrients. Study subjects exhibited no personal or family history of colon carcinoma, familial polyposis coli, sporadic adenomas, or chronic inflammatory bowel diseases. In this study population, a negative association between the tritiated thymidine-labeling index and dietary intake of calcium (p < 0.003) was found after the effects of age, sex, body mass index (kg/m2), dietary fat, and total energy were controlled in a linear regression model. The association for calcium indicated that a daily calcium intake of 1,200 mg was associated with a predicted thymidine-labeling index of 6%. In the same model, a positive association with the thymidine-labeling index was found for body mass index (p < 0.002) and was suggested for female gender (p < 0.09). No association was found between the thymidine-labeling index and intake of fat, protein, carbohydrate, retinol, ascorbic acid, phosphorus, or iron. Repeat measures of diet in this investigation were used to estimate a subject's daily intake of selected nutrients.

Functional block for 1 alpha,25-dihydroxyvitamin D3-mediated gene regulation in human B lymphocytes

Elements necessary for the steroid hormone 1 alpha,25-dihydroxyvitamin D3 (1 alpha,25-(OH)2D3) to induce a biological response include the presence of specific intracellular receptors (vitamin D3 receptors (VDR)) and modulation of gene expression via hormone-activated receptor binding to regulatory regions of target genes. These parameters were examined in normal and Epstein-Barr virus-immortalized human B cells and compared with 1 alpha,25-(OH)2D3-responsive cells of the T and monocytic lineages. Although resting tonsillar B cells did not express VDR mRNA, activation of these cells with interleukin-4 induced VDR in the absence of exogenously supplemented 1 alpha,25-(OH)2D3. As indicators of hormone-mediated gene regulation we analyzed modulation of CD23, a common B cell/monocyte surface antigen, and 24-hydroxylase. 1 alpha,25-(OH)2D3 inhibited CD23 expression in U937 cells, yet failed to modulate CD23 expression in B cells. Furthermore, 1 alpha,25-(OH)2D3 induced 24-hydroxylase mRNA expression and metabolic activity in both U937 cells and lectin-activated T cells, yet failed to induce 24-hydroxylase mRNA or its metabolic activity in B cells. These findings suggest that although human B lymphocytes can express VDR mRNA and protein, they exhibit a functional block for vitamin D-dependent gene regulation.

Unilateral parathyroidectomy: the value of the localizing scan

Surgery for correction of primary hyperparathyroidism utilizing a standard bilateral neck exploration has a success rate of approximately 90 to 95%. With the inception of pre-operative localization studies that were 90% accurate in localizing the diseased gland, the concept arose that a unilateral exploration could be as successful as a bilateral exploration. Bilateral exploration of the neck for hyperparathyroidism exposes the patient to a greater potential of morbidity for hypoparathyroidism and recurrent laryngeal nerve injury. It is our feeling based on personal experience that unilateral parathyroidectomy in selective cases can be as successful as the bilateral operation and be more cost effective, saving over $1,100 (U.S.) per case.

Severity of illness classification for infection control departments: a study in nosocomial pneumonia

BACKGROUND

A subjective severity of illness classification was evaluated in a study of nosocomial pneumonia. This is a 5-category system based on the determination of the control of underlying illness and the risk of death during current hospital admission.

METHODS

A case-control study was performed with 128 cases of nosocomial pneumonia and 252 control patients. An additional 60 case and 90 control patients were used to compare this classification with APACHE II scoring in intensive care unit patients.

RESULTS

In univariate analysis, the severity illness classification was significantly associated with nosocomial pneumonia risk (p < 0.01). APACHE II adequately predicted mortality rate but was not statistically significantly associated with nosocomial pneumonia risk among intensive care unit patients. In logistic regression analysis, the severity of illness classification, surgery, age, nasogastric tube placement, and histamine blockers each showed significant independent association with nosocomial pneumonia.

CONCLUSIONS

The role of the severity of illness classification for risk stratification in nosocomial pneumonia is valid. Its roles in the evaluation of surgical wound infection, nosocomial bacteremia, and quality of care remain to be determined in subsequent studies.

Rhenium-Osmium Isotope Constraints on the Age of Iron Meteorites

Rhenium and osmium concentrations and the osmium isotopic compositions of iron meteorites were determined by negative thermal ionization mass spectrometry. Data for the IIA iron meteorites define an isochron with an uncertainty of approximately +/-31 million years for meteorites approximately 4500 million years old. Although an absolute rheniumosmium closure age for this iron group cannot be as precisely constrained because of uncertainty in the decay constant of (187)Re, an age of 4460 million years ago is the minimum permitted by combined uncertainties. These age constraints imply that the parent body of the IIAB magmatic irons melted and subsequently cooled within 100 million years after the formation of the oldest portions of chondrites. Other iron meteorites plot above the IIA isocbron, indicating that the planetary bodies represented by these iron groups may have cooled significantly later than the parent body of the IIA irons.

Distribution of skeletal metastases in prostatic and lung cancer. Mechanisms of skeletal metastases

The distribution of skeletal metastases in prostatic and lung cancer was examined to test the hypothesis that prostatic carcinoma spreads by a unique hematogenous route. Abnormal technetium-99m methylene diphosphonate bone scans were retrospectively reviewed in 71 patients with prostatic carcinoma and 41 patients with lung cancer comparing patterns of osseous involvement. Differences in the distribution of lesions were not significant. It is concluded that prostatic carcinoma does not metastasize to specific skeletal sites by a singular hematogenous pathway.

Rhenium-Osmium and Samarium-Neodymium Isotopic Systematics of the Stillwater Complex

Isotopic data for the Stillwater Complex, Montana, which formed about 2700 Ma (million years ago), were obtained to evaluate the role of magma mixing in the formation of strategic platinum-group element (PGE) ore deposits. Neodymium and osmium isotopic data indicate that the intrusion formed from at least two geochemically distinct magmas. Ultramafic affinity (U-type) magmas had initial epsilon(Nd) of -0.8 to -3.2 and a chondritic initial (187)Os/(186)Os ratio of approximately 0.88, whereas anorthositic affinity (A-type) magmas had epsilon(Nd) of -0.7 to +1.7 and an initial (187)Os/(186)Os ratio of approximately -1.13. These data suggest that U-type magmas were derived from a lithospheric mantle source containing recycled crustal materials whereas A-type magmas originated either by crustal contamination of basaltic magmas or by partial melting of basalt in the lower crust. The Nd and Os isotopic data also suggest that Os, and probably the other PGEs in ore horizons such as the J-M Reef, was derived from A-type magmas. The Nd and Os isotopic heterogeneity observed in rocks below the J-M Reef also suggests that A-type magmas were injected into the Stillwater U-type magma chamber at several stages during the development of the Ultramafic series.

Rhenium-Osmium Isotope Systematics of Carbonaceous Chondrites

Rhenium and osmium concentrations and Os isotopic compositions of eight carbonaceous chondrites, one LL3 ordinary chondrite, and two iron meteorites were determined by resonance ionization mass spectrometry. Iron meteorite (187)Re/(186)Os and (l87)Os/(l86)Os ratios plot on the previously determined iron meteorite isochron, but most chondrite data plot 1 to 2 percent above this meteorite isochron. This suggests either that irons have significantly younger Re-Os closure ages than chondrites or that chondrites were formed from precursor materials with different chemical histories from the precursors of irons. Some samples of Semarkona (LL3) and Murray (C2M) meteorites plot 4 to 6 percent above the iron meteorite isochron, well above the field delineated by other chondrites. Murray may have lost Re by aqueous leaching during its preterrestrial history. Semarkona could have experienced a similar loss of Re, but only slight aqueous alteration is evident in the meteorite. Therefore, the isotopic composition of Semarkona could reflect assembly of isotopically heterogeneous components subsequent to 4.55 billion years ago or Os isotopic heterogeneities in the primordial solar nebula.

Abbreviated scheme for presumptive identification of Staphylococcus saprophyticus from urine cultures

A simplified scheme for the presumptive identification of Staphylococcus saprophyticus was investigated. Clinical isolates of Micrococcaceae were tested in microtiter plates containing phenol red-novobiocin-turanose broth and phenol red-arabinose broth. Standard saline suspensions of test organisms served as inoculum. Identifying features were growth within 18 to 24 h in novobiocin-turanose broth, indicating resistance to 1.6 micrograms of novobiocin per ml and fermentation of turanose. With this method, all clinical isolates of S. saprophyticus tested were correctly identified.

2,8-dihydroxyadenine urolithiasis: review of the literature and report of a case in the United States

Urolithiasis resulting from inherited metabolic derangement is rare. Only 13 cases of 2,8-dihydroxyadenine stones resulting from a deficiency of the enzyme adenine phosphoribosyl transferase have been reported since 1974. Of these cases 9 have been in children with the homozygous trait. To date, 3 homozygous and 1 heterozygous adults with urolithiasis have been reported. This disease has not been associated with any other clinical or biochemical abnormalities. Treatment includes low purine diet and allopurinol. We herein report a case of complete adenine phosphoribosyl transferase deficiency associated with 2,8-dihydroxyadenine urolithiasis in the United States, bringing the total to 14 in the literature.

Long-term growth of human B cells and their use in a microassay for B-cell growth factor

Normal human B lymphocytes, prepared from peripheral venous blood, have been stimulated with intact anti-IgM (mu chain specific) bound to an insoluble matrix. The activation event, in a subfraction of human B cells, was associated with subsequent receptivity to the mitogenic effects of exogenously added B-cell growth factor. The ability of the cell population to specifically absorb the B-cell growth factor was dependent upon the time of stimulation with the anti-IgM. Continuous replenishment of the growth factor resulted in the ability to maintain long-term growth-factor-dependent human B-cell populations. These cultured B lymphocytes were shown to specifically absorb the B-cell growth factor, suggesting the presence of membrane receptors for it. The cultured B lymphocytes were routinely maintained in logarithmic-phase growth, in the presence of growth factor, with a population doubling time of 36 hr. These cultured B cells have been utilized in a microassay for the assessment of B-cell growth factor activity that is accurate, sensitive, and precise.

Nosocomial Pseudomonas aeruginosa urinary tract infections

Two separate outbreaks of Pseudomonas aeruginosa urinary tract infections (UTIs) were associated with cystoscopy or transurethral prostate resection. The first outbreak was identified after routine bacteremia surveillance demonstrated four cases of P aeruginosa septicemia in a three-month period. A six-month retrospective review of the microbiology records identified 14 cases of P aeruginosa UTI associated with urologic surgery instrumentation. The outbreak terminated after the implementation of two major control measures: (1) replacement of hexachlorophene solution with an iodophor solution for preparing patients and cleaning instruments before disinfection, and (2) weekly gas sterilization of cystoscopy instruments. The second outbreak, consisting of 11 cases of P aeruginosa UTI after transurethral resection of the prostate gland, occurred in a 187-bed community hospital. All available patient isolates were serotype 011, and culture of a rubber adaptor attached to the resectoscope also yielded growth of that serotype. The outbreak promptly terminated when the rubber adaptor was sterilized between cases.

Supressor monocytes in patients with systemic lupus erythematosus. Evidence of suppressor activity associated with a cell-free soluble product of monocytes

Abnormal SLE mononuclear cell responses to PHA can be corrected by removal of adherent mononuclear cells. The present study demonstrates that cell-free supernatants from allogeneic adherent cell cultures inhibit lymphocyte response and that addition of indomethacin to cultures partly blocks the inhibitory effect of the resulting supernatant. Supernatants from SLE monocyte cultures suppressed allogeneic normal T cell responses by 36% (response in supernatant 33,515 +/- 3814 cpm, media control 51,947 +/- 3173 cpm) but normal monocyte culture supernatants did not suppress (48,384 +/- 4172 vs. 47,477 +/- 3221 cpm). Early (less than 24 hr) addition of indomethacin to monocyte cultures prevented elaboration of inhibitory material. In normals, indomethacin-treated supernatants were strikingly stimulatory (response 178% +/- 24 of control), whereas similarly treated supernatants of SLE monocyte cultures were not stimulatory (response 103% +/- 8 of control). The data indicate that a soluble inhibitor of lymphocyte blastogenesis is produced by SLE monocytes.

Volatile Elements in Apollo 16 Samples: Possible Evidence for Outgassing of the Moon

Several Apollo 16 breccias, including one containing goethite, are strikingly enriched in volatile elements such as bromine, cadmium, germanium, antimony, thallium, and zinc. Similar but smaller enrichments are found in all highland soils. It appears that volcanic processes took place in the lunar highlands, involving the release of volatiles including water. The lunar thallium/uranium ratio is 2 x 10-(4) of the cosmic ratio, which suggests that the moon's original water content could not have exceeded the equivalent of a layer 22 meters deep. The cataclastic anorthosites at the Apollo 16 site may represent deep ejecta from the Nectaris basin.

Moon: Possible Nature of the Body That Produced the Imbrian Basin, from the Composition of Apollo 14 Samples

Soils from the Apollo 14 site contain nearly three times as much meteoritic material as soils from the Apollo 11, Apollo 12, and Luna 16 sites. Part of this material consists of the ubiquitous micrometeorite component, of primitive (carbonaceous-chondrite-like) composition. The remainder, seen most conspicuously in coarse glass and norite fragments, has a decidedly fractionated composition, with volatile elements less than one-tenth as abundant as siderophiles. This material seems to be debris of the Cyprus-sized planetesimal that produced the Imbrian basin. Compositionally this planetesimal has no exact counterpart among known meteorite classes, though group IVA irons come close. It also resembles the initial composition of the earth as postulated by the two-component model. Apparently the Imbrian planetesimal was an Earth satellite swept up by the moon during tidal recession or capture, or an asteroid deflected by Mars into terrestrial space.

Glazed Lunar Rocks: Origin by Impact

The glassy coating of lunar rock 12017 is enriched in 15 trace elements relative to the crystalline interior. It apparently consists chiefly of shock-melted rock, somewhat richer in rare earth elements and alkali metals than rock 12017 itself. The glass has been contaminated by about 0.5 percent carbonaceous-chondrite-like material or, alternatively, by a mixture of 0.06 to 0.3 percent fractionated meteoritic material and approximately 10 to 15 percent local soil. The glazing seems to represent molten material splashed from a nearby meteorite impact and not in situ melting by a sudden increase in solar luminosity.