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S Bang

Publications and source records attributed to S Bang.

At least 19 recordsLinked to original sources
PubMed2025

HLA-E and NKG2A Mediate Resistance to BCG Immunotherapy in Non-Muscle-Invasive Bladder Cancer.

Bacillus Calmette-Guérin (BCG) is the first-line therapy for high-grade non-muscle-invasive bladder cancer (NMIBC), yet many patients experience recurrence due to immune evasion. We identify HLA-E and NKG2A as mediators of adaptive resistance involving chronic activation of NK and T cells in BCG-unresponsive tumors. Prolonged IFN-γ exposure enhances HLA-E and PD-L1 expression on recurrent tumors, accompanied by the accumulation of NKG2A+ NK and CD8 T cells. HLA-Ehigh tumor cells preferentially cluster near CXCL12-rich stromal regions with dense effector cell presence, underscoring a spatially segregated tumor architecture. Although cytotoxic lymphocytes retain effector potential, their activity is restrained by HLA-E/NKG2A and PD-L1/PD-1 pathways located in their immediate neighborhood within the bladder tumor microenvironment. These data reveal a spatially organized immune escape program that limits anti-tumor immunity. Our findings support dually targeting NKG2A and PD-L1 checkpoint blockade as a rational, bladder-sparing strategy for patients with BCG-unresponsive NMIBC.

BCG-unresponsive↗
PubMed1992

Implicit and explicit memory in young, old, and demented adults.

Previous study of scopolamine and memory (Grober et al., 1989) showed that young adults given moderate or high doses of scopolamine maintained maximum cued recall in spite of a dose-dependent decrement in free recall when memory was assessed by cued selective reminding (CSR), a procedure which circumvents inattention and induces semantic processing. Intact recall by CSR indicates either that scopolamine impairs memory indirectly through effects on attention and information processing or that it impairs explicit memory but not implicit memory. In the present study which was done to determine if CSR reflects explicit or implicit memory, a free association test was used to estimate implicit memory after CSR was administered; explicit memory was estimated with a final trial of cued recall. Data from young, nondemented, and demented adults indicate that CSR reflects explicit memory supporting the interpretation of the previous study that scopolamine does not produce direct impairment of explicit memory.

Adolescent↗
PubMed1992

Effects of the prostaglandin E2 analogue enprostil on the carbon tetrachloride-induced necrosis of liver cells in mice.

Female mice, eight weeks old, were injected with carbon tetrachloride (CCl4) (10 mg subcutaneously). Groups of mice (n = 10-30) were then injected with enprostil (E) 2, 20 or 50 micrograms/kg body weight (bw) intraperitoneally 15 min and two h after, or E 100 micrograms/kg bw two h after the CCl4 injection. The mice were killed after 24, 48 or 72 h. Plasma activity concentrations of alanine aminotransferase (ALAT) were determined in blood specimens from the iliac veins. The extent of liver cell necrosis in histological sections was recorded on a 100 mm Visual Analogue Scale (VAS) and measured using the electronic Mini Mop method. In the group given the highest single dose of E (100 micrograms/kg) a significant lowering of the CCl4-induced liver cell necrosis was found after 24 h. No significant differences were found after 48 and 72 h. In the other groups injected with lower doses of E after CCl4, no significant differences were found compared to groups injected with CCl4 alone.

Alanine Transaminase↗
PubMed1991

Validation of a semiquantitative food frequency questionnaire developed in Denmark.

In 1989, a self-administered food frequency questionnaire, including 92 food items and 40 portion-size photographs, was validated against two times seven days of weighed diet records. A total of 144 subjects, aged 40-64 years, from the general population in Copenhagen were included. Correlations between mean calorie-adjusted intakes from the two-week diet records and the food-frequency questionnaire ranged from 0.27 for vitamin A to 0.71 for calcium. In general, higher correlation coefficients were observed for men than for women. On average, about 70% of subjects were classified in the same (+/- 1) quintile in the food frequency questionnaire and the diet records. Of those subjects belonging to the lowest quintile, estimated from the diet records, 42% fell in the same quintile and 68% into the lowest two quintiles in the food frequency questionnaire. Findings were similar for the upper tail of the distribution. Gross misclassification, observed in the highest and lowest quintile, was found for 4% and 7% of the subjects, respectively. It is concluded that this food frequency questionnaire is a useful instrument for categorizing individuals according to their intake of nutrients and energy.

Adult↗
PubMed1991

Effect of the prostaglandin E1 analogue misoprostol on the carbon tetrachloride-induced injury of rat liver cells in culture.

Previous investigators have reported a protective effect of some prostaglandins and of the prostaglandin E2 analogue enprostil on carbon tetrachloride (CCl4)-induced injury of liver cells. In the present study liver cells were isolated from the rat liver by collagenase perfusion and suspended in F-10 medium, containing 20% foetal bovine serum, 1% gentamicin, and 1% glutamine. In the first study cells were cultured in T-flasks with 3 ml suspension of 6 x 10(6) cells/ml, and in the second study (extended dose response) cells were cultured in tissue culture wells with 0.5 ml cell suspension. Misoprostol was added to groups of cultures 15 min before CCl4, 2 microliters/ml, and the number of living cells was counted 45 min after the first addition. The number of living cells was compared with those of other groups with CCl4 only and control groups. In the first experiment misoprostol was given in doses of 200, 400, and 800 ng/ml medium and in the second experiment in 0.1, 1, 10, 100, and 1000 ng/ml medium. CCl4 is an agent well known to be toxic to liver cells, and in cultures to which only CCl4 was added, the number of living cells was significantly reduced compared with controls. When 0.1 ng misoprostol was added before CCl4, no significant difference in the number of living cells was shown compared with cultures with CCl4 only. On the other hand, misoprostol given in doses from 1 ng to 1000 ng before CCl4 resulted in a higher number of living cells, indicating a protective effect.

Animals↗
PubMed1991

[The evolution of carboxyhemoglobin during long-term closed-circuit anesthesia].

In 40 patients who underwent protracted orthodontic operations, the accumulation of carboxyhemoglobin (COHb) in the blood was studied. Mechanical ventilation during anesthesia was carried out in a closed system (group I, n = 20). Patients in a control group received mechanical ventilation with a constant fresh gas flow of 6 l/min (group II, n = 20). During closed-system ventilation, a constant rise of COHb was observed. Smokers had much higher COHb values than nonsmokers at the beginning of and during anesthesia. The relative increase of COHb in a defined time period was of the same magnitude for smokers and nonsmokers. Critical values for carbon monoxide (CO) intoxication were not measured. The mean rise was 0.05 g/100 ml COHb over 6 h. Two female patients had COHb rises of 0.29 g/100 ml and 0.18 g/100 ml over the same period. During ventilation with a high flow of fresh gas, the COHb level decreased in all patients. In nonsmokers, the value approached the physiological range of 0.4% to 0.8% COHb. A marked fall of COHb could also be observed in smokers; however, normal physiological values were not reached. Patients with low COHb tolerance (anemia, severe coronary heart disease, peripheral vascular disease) or with increased endogenous CO production (pregnancy, newborns, hemolytic disease, porphyria cutanea) should not undergo protracted ventilation in a closed circle system.

Adult↗
PubMed1990

Topographical distribution of fluoride in iliac bone of a fluoride-treated osteoporotic patient.

The electron microprobe was used to display the topographical distribution pattern of fluoride (F) at the microscopical level in the iliac bone of an osteoporotic patient treated with fluoride. Composite x-ray image of F K alpha emission revealed a high concentration of fluoride in the periosteal and endosteal bone layers, in the cancellous bone, and in certain osteons, which corresponded to the bone formed during the period of fluoride treatment. Fluoride was also concentrated around the Haversian canals in the vicinity of the capillary blood vessels by a diffusion process. Morphometric analysis showed that more cancellous bone than cortical bone is formed.

Aged↗
PubMed1989

Liver cell necrosis and regeneration following injections of carbon tetrachloride. Effects of the thyrotropin-releasing hormone and somatostatin.

Mice were given 10 micrograms somatostatin or 25 micrograms TRH intraperitoneally 10 min before s.c. injection of 2 or 20 mg CCl4. The extent of liver cell necrosis and nuclear size were measured by the electronic Mini Mop method and the extent of necrosis and nuclear pleomorphism were estimated by a visual linear analogue scale of 100 mm, and compared to plasma concentrations of ASAT and ALAT. Pre-treatment with TRH or somatostatin resulted in significant reduction in the extent of necrosis 24 h after CCl4-injections (25%), with a lowering of ASAT from 13209 +/- 2955 U/l to 5144 +/- 924 after TRH and to 6186 +/- 966 after somatostatin, and of ALAT from 14343 +/- 3209 to 7718 +/- 1727 and 6494 +/- 1253 U/l, respectively. After 3 days the necroses were reduced from 16.5 +/- 1.7% by the Minimop method to 1.4 +/- 0.5% (90%) in mice given CCl4 alone, and from 12.3 +/- 1.7% to 3.8 +/- 1.2% in mice pretreated with TRH, and from 12.3 +/- 1.8% to 3.8 +/- 1.7% (70%) in mice pretreated with somatostatin. The plasma concentrations of ASAT and ALAT were reduced correspondingly. After 5 days no necroses were seen, and the plasma ASAT and ALAT were normal. After 6 months of weekly injections of TRH or somatostatin before 20 mg CCl4 the liver cell nuclear size (10.5 and 9.7 0.3 mu 2) was similar to that after CCl4 alone (9.7 0.3 mu 2), and twice that of controls (4.6-5.4 0.1 mu 2). Liver cell necrosis was not seen. The plasma concentrations of ASAT (131 8.6-162 11.3) and ALAT (98 8-104 9 Iu/l) were similarly 2-3 times those in controls. TRH and somatostatin thus reduced liver cell injury and delayed regeneration after single injections of CCl4. After 6 months of weekly injections no effects were observed.

Animals↗
PubMed1988

Screening for dementia by memory testing.

Enhanced cued recall provides a simple and clinically useful memory test for identifying dementia in the elderly. Because this test induces semantic processing and coordinates encoding and retrieval for maximum recall, genuine memory deficits due to impairment of specific memory processes can be distinguished from apparent memory deficits due to use of inefficient strategies or impairment of other cognitive processes. Since genuine memory deficits in the elderly are usually associated with dementia, their identification is highly predictive of clinical dementia. The present study validates the use of enhanced cued recall as a screening test for dementia in 70 aged subjects. All but one person with a pure amnesia were correctly classified. Enhanced cued recall correctly classified 97% of the 120 subjects in this and the previous study. Enhanced cued recall shows learning not revealed by free recall, providing more accurate measurement of memory, and distinguishes demented from nondemented elderly more accurately than either free recall or recognition.

Aged↗
PubMed1988

Prostaglandins and CCl4-induced liver cell mortality. The effect of the prostaglandin analogue enprostil.

Prostaglandins have been reported to reduce the carbon tetrachloride (CCl4)-induced liver cell injury in rats. The object of the present experiments was to examine the effect of the prostaglandin E2 analogue enprostil on the survival of isolated liver cells exposed to CCl4. Liver parenchymal cells were isolated from rat livers by collagenase perfusion and released into a 'suspension' buffer. Aliquots of the cell suspension were incubated with 1 micrograms or 0.5 microgram CCl4, and to parallel test suspensions 20 ng enprostil was added 5-10 min before CCl4. Incubation was performed on ice, at room temperature, and at 37 degrees C. The average percentage of dead cells after CCl4 treatment was significantly reduced by pretreatment with enprostil at room temperature (1 microgram CCl4: 69 +/- 21% and 44 +/- 13%, respectively) and after 10 min of incubation at 37 degrees C (1 microgram Cl4: 56 +/- 25% and 37 +/- 27%; 0.5 microgram CCl4: 51 +/- 33% and 29 +/- 18%, respectively). When the liver cell mortality approximated 100% after long-term incubation at 37 degrees C, no protective effect of enprostil was observed.

Animals↗
PubMed1985

Distribution of fluoride in calcified cartilage of a fluoride-treated osteoporotic patient.

Subchondral bone and calcified cartilage from a femoral head of a 74-year-old osteoporotic woman treated for 30 months with sodium fluoride were analyzed. The fluoride content of the calcified tissues was determined by a specific ion electrode, and the topographic distribution pattern of fluoride was determined with an electron microprobe. The fluoride content in calcified cartilage (0.39% of ash) was higher than in neighboring subchondral bone (0.28% of ash). Line scan and X-ray images indicated a high concentration of fluoride in the outer layer of calcified cartilage lining the uncalcified cartilage, as well as in the inner layer of the subcortical endosteal bone. This study shows that calcified cartilage is an important site of fluoride deposition, and suggests that the accumulation of fluoride is related to the calcification process.

Aged↗
PubMed1982

Calcium phosphate metabolism and bone disease in patients with homozygous thalassemia.

Calcium and phosphate metabolism were studied in 22 patients with homozygous thalassemia. The overall results showed no significant difference for serum calcium, phosphorus, alkaline phosphatase, immunoreactive parathyroid hormone, or 25-hydroxyvitamin D between thalassemic and control children. However, during the winter, serum 25-hydroxycholecalciferol levels were very significantly decreased in thalassemic children. A study of the hands showed thin metacarpal cortices related to increased resorption. Histomorphometric study of four iliac bone biopsies showed normal osteoclastic resorption and decreased bone formation. Prussian blue staining and x-ray electron microprobe analysis showed iron deposits inside the bone. Whether this finding is critical in the pathogenesis of the bone disease in unknown.

Adolescent↗
PubMed1977

[Prolactin].

Explore the source record for details and available documents.

Female↗
PubMed1977

Inhibition of prolactin secretion and synthesis by dopamine, noradrenaline and pilocarpine in cultured rat pituitary tumour cells.

Clonal strains of rat pituitary tumour cells (GH3-cells) synthesize and secrete prolactin into a chemically defined culture medium. Short time treatment (0.5-2 hrs) of cell cultures with noradrenaline (10(-3) M) and dopamine (10(-3 M) reduced the spontaneous secretion of prolactin by 50% and 30%, respectively, while pilocarpine (10(-3) M) had no effect. Long-term treatment (20 hrs) with noradrenaline (10(-3)M) or with pilocarpine (10(-3) M) inhibited prolactin synthesis by 45% and 65% of control cultures, respectively. Neither compounds affected cell growth. The inhibitory effect of noradrenaline, but not that of pilocarpine, was completely reversed 4 hrs after cessation of treatment. Adrenaline, dopamine and acetylcholine in concentrations up to 10(-3) M did not change prolactin synthesis. In contrast thyroliberin treatment (2 X 10(-8)M) caused a 45% increase in prolactin secretion, and resulted in a 40% increase in hormone synthesis after treatment for 20 hrs. It is concluded that both noradrenaline and dopamine are able to inhibit prolactin section. Prolactin synthesis could be inhibited by noradrenaline and pilocarpine. How, only the effect of noradrenaline is easily reversible on cessation of treatment.

Animals↗
PubMed1977

Minor elements in bone mineral and their effects on its solubility.

Mineral substance deposited in bone tissue when either strontium or fluoride are present, is both qualitatively and quantitatively different from that deposited in their absence. The presence of these ions causes not only heteroíonic substitutions in the crystalline lattice of the apatite phase, but also important modifications of the percentage of crystalline mineral, of crystal size and perfection, and of quantity of mineral per unit volume. These modifications affect the in vitro and in vivo demineralization of bone tissue.

Animals↗