Safety and efficacy of nivolumab and standard chemotherapy drug combination in patients with advanced non-small-cell lung cancer: a four arms phase Ib study.

BACKGROUND: The human IgG4 monoclonal antibody nivolumab targets programmed cell death-1 (PD-1) and promotes antitumor response by blocking the interaction of PD-1 with its ligands. This single-center phase Ib study investigated the tolerability, safety, and pharmacokinetics of nivolumab combined with standard chemotherapy in patients with advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Patients who had stage IIIB without indication for definitive radiotherapy, stage IV, or recurrent NSCLC were eligible. Regimens were nivolumab 10 mg/kg + gemcitabine/cisplatin (arm A), pemetrexed/cisplatin (arm B), paclitaxel/carboplatin/bevacizumab (arm C), or docetaxel (arm D). Regimens A, B, and D were repeated every 3 weeks for up to four cycles and regimen C was repeated for up to six cycles; nivolumab alone (arm A), with pemetrexed (arm B), bevacizumab (arm C), or docetaxel (arm D) was continued every 3 weeks as maintenance therapy until disease progression or unacceptable toxicity. Dose-limiting toxicity (DLT) was evaluated during the first treatment cycle. RESULTS: As of March 2014, six patients were enrolled in each arm. The combination of nivolumab 10 mg/kg and chemotherapy was well tolerated. DLT was observed in only one patient in arm A (alanine aminotransferase increased). Select adverse events (those with a potential immunologic cause) of any grade were observed in six, four, six, and five patients in arms A, B, C, and D, respectively. Three, three, six, and one patient achieved partial response while median progression-free survival was 6.28, 9.63 months, not reached, and 3.15 months in arms A, B, C, and D, respectively. CONCLUSIONS: Combination of nivolumab 10 mg/kg and chemotherapy showed an acceptable toxicity profile and encouraging antitumor activity in patients with advanced NSCLC. CLINICAL TRIALS NUMBER: Japanese Pharmaceutical Information Center Clinical Trials Information (JapicCTI)-132071.

Peroxiredoxin 6 delivery attenuates TNF-alpha-and glutamate-induced retinal ganglion cell death by limiting ROS levels and maintaining Ca2+ homeostasis.

Higher expression of reactive oxygen species (ROS) is implicated in neurological disorders. A major event in glaucoma, the death of retinal ganglion cells (RGCs), has been associated with elevated levels of glutamate and TNF-alpha in the RGCs' local microenvironment. Herein we show that the transduction of Peroxiredoxin 6 (PRDX6) attenuates TNF-alpha- and glutamate-induced RGC death, by limiting ROS and maintaining Ca2+ homeostasis. Immunohistochemical staining of rat retina disclosed the presence of PRDX6 in RGCs, and Western and real-time PCR analysis revealed an abundance of PRDX6 protein and mRNA. RGCs treated with glutamate and/or TNF-alpha displayed elevated levels of ROS and reduced expression of PRDX6, and underwent apoptosis. A supply of PRDX6 protected RGCs from glutamate and TNF-alpha induced cytotoxicity by reducing ROS level and NF-kappaB activation, and limiting increased intracellular Ca2+ influx. Results provide a rationale for use of PRDX6 for blocking ROS-mediated pathophysiology in glaucoma and other neuronal disorders.

DNA binding domains and nuclear localization signal of LEDGF: contribution of two helix-turn-helix (HTH)-like domains and a stretch of 58 amino acids of the N-terminal to the trans-activation potential of LEDGF.

Lens epithelium derived growth factor (LEDGF), a nuclear protein, plays a role in regulating the transcription of stress-associated genes such as heat shock proteins by binding to consensus core DNA sequences nAGGn or nGAAn or their repeats, and in doing so helps to provide cyto-protection. However, additional information is required to identify the specific structural features of LEDGF involved in gene transcription. Here we have investigated the functional domains activating and repressing DNA-binding modules, by using a DNA binding assay and trans-activation experiments performed by analyzing proteins prepared from deletion constructs. The results disclosed the DNA-binding domain of N-terminal LEDGF mapped between amino acid residues 5 and 62, a 58 amino acid residue stretch PWWP domain which binds to stress response elements (STRE; A/TGGGGA/T). C-terminal LEDGF contains activation domains, an extensive loop-region (aa 418-530) with two helix-turn-helix (HTH)-like domains, and binds to a heat shock element (HSE; nGAAn). A trans-activation assay using Hsp27 promoter revealed that both HTH domains contribute in a cooperative manner to the trans-activation potential of LEDGF. Interestingly, removal of N-terminal LEDGF (aa 1-187) significantly enhances the gene activation potential of C-terminal LEDGF (aa 199-530); thus the N-terminal domain (aa 5-62), exhibits auto-transcriptional repression activity. It appears that this domain is involved in stabilizing the LEDGF-DNA binding complex. Collectively, our results demonstrate that LEDGF contains three DNA-binding domains, which regulate gene expression depending on cellular microenvironment and thus modify the physiology of cells to maintain cellular homeostasis.

Acid-catalyzed rearrangement of aryl-substituted homobenzoquinone epoxides.

The BF3-catalyzed reactions of diphenyl-substituted and endo-monophenyl-substituted homobenzoquinone epoxides proceeded through a regioselective oxirane ring opening followed by participation of a pi-aryl transannular cyclization to give the tricyclic diketo alcohols. The conformationally semirigid ethano-bridged diphenyl-substituted homologues also provided similar diketo alcohols and the subsequent ring-expanded cycloheptenedione (via a subsequent 1,2-acyl migration associated with cyclopropane ring opening), depending on the methyl-substitution pattern of the quinone frame. However, the exo-monophenyl-substituted and the rigid biphenyl-2,2'-diyl-substituted homobenzoquinone epoxides essentially remained unchanged.

Impaired homeostasis and phenotypic abnormalities in Prdx6-/-mice lens epithelial cells by reactive oxygen species: increased expression and activation of TGFbeta.

PRDX6, a member of the peroxiredoxins (PRDXs) family, is a key player in the removal of reactive oxygen species (ROS). Using targeted inactivation of the Prdx6 gene, we present evidence that the corresponding protein offsets the deleterious effects of ROS on lens epithelial cells (LECs) and regulates gene expression by limiting its levels. PRDX6-depleted LECs displayed phenotypic alterations and elevated alpha-smooth muscle actin and betaig-h3 expression (markers for cataractogenesis), indistinguishable from transforming growth factor beta (TGFbeta)-induced changes. Biochemical assays disclosed enhanced levels of ROS, as well as high expression and activation of TGFbeta1 in Prdx6-/- LECs. A CAT assay revealed transcriptional repression of lens epithelium-derived growth factor (LEDGF), HSP27, and alphaB-crystallin promoter activities in these cells. A gel mobility shift assay demonstrated the attenuation of LEDGF binding to heat shock or stress response elements present in these genes. A supply of PRDX6 toPrdx6-/- LECs reversed these changes. Based on the above data, we propose a rheostat role for PRDX6 in regulating gene expression by controlling the ROS level to maintain cellular homeostasis.

Axial length, myopia, and the severity of lens opacity at the time of cataract surgery.

OBJECTIVE: To investigate the relationship between axial length, myopia of the eye, and the severity of lens opacity at the time of cataract surgery. METHODS: We retrospectively reviewed a consecutive series of 198 eyes of patients aged older than 50 years at Fukui University Hospital (Fukui, Japan) from June 2004 to December 2005. Patient age at the time of surgery, axial length, spherical equivalent, and the subtypes and severity of cataract (as classified according to the modification of the Lens Opacities Classification System, version III) were recorded. RESULTS: Axial length was significantly associated with age at the time of cataract surgery (P<.001). Regarding the severity of nuclear cataract, a significant correlation was seen between a higher score of nuclear cataract and longer axial length (P<.001). The relationship between the severity of nuclear cataract and spherical equivalent at the time of surgery showed a significant association between grading nuclear color and nuclear opalescence 4-6 and higher myopia (P<.001). CONCLUSION: An increase in axial length or myopia of the eye was associated with a lower mean age at the time of surgery and higher grade of nuclear cataract.

Development of prelymphoma cells committed to thymic lymphomas during radiation-induced thymic lymphomagenesis in B10 mice.

Intrathymic (i.t.) as well as i.p. injection of thymus cells from B10.Thy-1.1 mice manifesting overt thymic lymphomas, 4 months after split-dose irradiation, into B10.Thy-1.2 recipient mice resulted in the development of donor-type T-cell lymphomas, indicating that they contained "autonomous" lymphoma cells. In contrast, injection of thymus cells from apparently nonleukemic mice 1 month after split-dose irradiation resulted in the development of donor-type tumors only when they were injected i.t., suggesting that thymus cells from these mice contained "preneoplastic" cells that will eventually develop into thymic lymphomas under the influence of thymic microenvironment. These "thymus-dependent" preneoplastic cells were termed "thymic prelymphoma cells." With the use of i.t. injection assay, it was shown that these thymic prelymphoma cells were detected in 26.1% (6 of 23) of the test donor thymuses when examined at 14 days and in more than 63% (15 of 24 and 14 of 22) when examined at 21 and 31 days after irradiation. To examine the possibility that thymic prelymphoma cells might appear first in the bone marrow before they become detectable within the thymuses of the split-dose-irradiated mice, bone marrow cells from B10.Thy-1.1 donors recovered at 8, 14, 21, and 33 days after split-dose irradiation were also injected i.t. into B10.Thy-1.2-recipient mice. The results indicated that none of these recipients developed donor-type T-cell lymphomas, suggesting that bone marrow is not the first site of the appearance of thymic prelymphoma cells.

Reconfirmation of indirect induction of radiogenic lymphomas using thymectomized, irradiated B10 mice grafted with neonatal thymuses from Thy 1 congenic donors.

An experiment was conducted to reexamine earlier observations that lymphomas could develop from lymphocytes present in nonirradiated thymuses grafted into thymectomized, fractionally (170 R, 4 doses) irradiated mice by using B10. Thy 1 congenic donor-host combinations. The results indicated that: (a) 37 of 91 thymectomized, fractionally irradiated B10. Thy 1.2 mice which were grafted s.c. with 7-day-old thymuses from B10. Thy 1.1 donor mice had developed frank lymphomas between 90 and 270 days after thymus grafting; (b) 28 of 37 lymphomas developed in this group were typed individually with respect to Thy 1 alloantigens by the cytotoxicity assay using monoclonal anti-Thy 1.1 (T-11-D7) and anti-Thy 1.2 (F7D5) antibodies plus complement. It was shown that 21 thymic lymphomas (75%) had originated from lymphocytes of the nonirradiated thymus grafts and 5 tumors (17.9%) from cells of the irradiated hosts; 2 thymic lymphomas (7.1%) manifested no Thy 1 antigens; (c) lymphoma cells originated from both nonirradiated thymus grafts and irradiated hosts possessed chromosome abnormalities, which were mainly numerical changes of some chromosomes or polyploidizations.

Transactivation of involucrin, a marker of differentiation in keratinocytes, by lens epithelium-derived growth factor (LEDGF).

Human involucrin (hINV), first appears in the cytosol of keratinocytes and ultimately cross-linked to membrane proteins via transglutaminase and forms a protective barrier as an insoluble envelope beneath the plasma membrane. Although the function and evolution of involucrin is known, the regulation of its gene expression is not well understood. An analysis of the hINV gene sequence, upstream of the transcription start site (-534 to +1 nt) revealed the presence of potential sites for binding of lens epithelium-derived growth factor (LEDGF); stress response element (STRE; A/TGGGGA/T) and heat shock element (HSE; nGAAn). We reported earlier that LEDGF activates stress-associated genes by binding to these elements and elevates cellular resistance to various stresses. Here, gel-shift and super-shift assays confirm the binding of LEDGF to the DNA fragments containing HSEs and STREs that are present in the involucrin gene promoter. Furthermore, hINV promoter linked to CAT reporter gene, cotransfected in human corneal simian virus 40-transformed keratinocytes (HCK), was transactivated by LEDGF significantly. In contrast, the activity of hINV promoter bearing mutations at the WT1 (containing HSE and STRE), WT2 (containing STRE) and WT3 (containing STRE) binding sites was diminished. In addition, in HCK cell over-expressing LEDGF, the levels of hINV mRNA and hINV protein are increased by four to five-fold. LEDGF is inducible to oxidants. Cells treated with 12-O-tetradecanoyl-phorbol-13-acetate (TPA), known to stimulate production of H(2)O(2), showed higher levels of LEDGF mRNA. Furthermore, our immunohistochemical studies revealed that hINV protein is found in the cytoplasm of HCK cells over-expressing LEDGF, but not detectable in the normal HCK cells or HCK cells transfected with vector. This regulation appears to be physiologically important, as over-expression of HCK with LEDGF increases the expression of the endogenous hINV gene and may provide new insight to understand the molecular mechanism of transcriptional regulation of this gene. LEDGF may play an important role in establishing an important barrier in corneal keratinocytes by maintaining epidermal turn-over rate, and protecting HCKs against stress.

The characterization of the monoclonal antibody Th-10a, specific for a nuclear protein appearing in the S phase of the cell cycle in normal thymocytes and its unregulated expression in lymphoma cell lines.

A monoclonal antibody (Th-10a) specific for the nuclear protein appearing in the S phase of the cell cycle in normal mouse thymocytes was derived by immunizing Wistar rats with a murine thymic lymphoma (TIGN), and its isotype was rat IgG2a and had kappa light chain. Immunohistochemical staining of frozen sections of B10.Thy1.1 newborn thymus and embryonic intestine revealed that this monoclonal antibody reacted strongly with the nuclear proteins of subcortical thymocytes and the basal layer of the mucosa, where many cells were dividing, but not with that of the thymic medullary area. To evaluate the expression of the nuclear proteins during the cell cycle in detail, the results of an immunofluorescence analysis of the thymocytes from hydroxyurea-treated B10 mice using Th-10a monoclonal antibody were compared with those of DNA synthesis of these cells with the use of the FITC-conjugated anti-BrdUrd monoclonal antibody. The results indicated that the nuclear protein detected by Th-10a monoclonal antibody was highly expressed in the S phase of normal thymocytes, while the cells in G1, G2 and M phases exhibited a low level of the expression. Moreover, the variations in expression of the nuclear proteins in the thymocytes at different times after hydroxyurea treatment were observed to correspond with the frequency of DNA synthesizing cells. In contrast, the high level and unregulated expression of the nuclear protein detected by Th-10a monoclonal antibody was observed throughout the cell cycle of the mouse lymphoma cell lines examined. Since Th-10a monoclonal antibody does not react with the nuclear proteins derived from human, hamster or rat proliferating cells, this antibody may recognize a murine specific epitope of the nuclear protein. To further characterize the nuclear proteins, we extracted them from normal thymocytes or thymic lymphomas, and analysed them by immunoblotting or immunoprecipitation followed by SDS-polyacrylamide gel electrophoresis. The nuclear protein(s) detected by Th-10a monoclonal antibody was mostly 95 kDa and also 83 kDa polypeptide. The results also indicated that the 95 kDa nuclear protein was phosphorylated in vivo.

LEDGF: survival of embryonic chick retinal photoreceptor cells.

PURPOSE: Lens epithelium-derived growth factor (LEDGF) is a novel adhesive, survival, and growth factor for lens epithelial cells, keratinocytes, fibroblasts, and cos7 cells. In the presence of LEDGF, these cells acquire resistance to environmental stresses, and in the absence of LEDGF they die. The effects of LEDGF on survival of embryonic chick retinal photoreceptor cells under serum starvation and heat stress were studied. METHODS: The expression pattern of LEDGF in embryonic chick retinal photoreceptor cells was investigated with protein blot analysis and immunohistochemistry using antibodies (Abs) to LEDGF. Retinal cells were cultured in serum-free medium for up to 6 days in the presence of varying amounts of LEDGF at 37 degrees or 41 degrees C. The photoreceptor cells were immunostained with Abs to arrestin and counted to evaluate the photoreceptor cell viability. Heat shock proteins in the cultured cells were quantified by protein blot analysis with Ab probes and semiquantitative reverse transcription-polymerase chain reaction analysis. RESULTS: LEDGF was found predominantly in the nucleus of neuroretinal cells, including photoreceptor cells. In the presence of LEDGF, photoreceptor cells manifested increased resistance to serum starvation and thermal stress and survived for a longer period. The levels of heat shock protein 90 were elevated in those cells. Most retinal cells died in the absence of LEDGF. CONCLUSIONS: LEDGF enhanced survival of retinal photoreceptor cells under serum starvation and heat stress. Thus, LEDGF has a potency to enhance survival of neuronal cell types against environmental stresses, and it may be applicable as a therapeutic agent for those cells.

3-FG as substrate for investigating flux through the polyol pathway in dog lens by 19F-NMR spectroscopy.

PURPOSE: To investigate flux through the polyol pathway in the dog lens by 19F-nuclear magnetic resonance (19F-NMR) spectroscopy, using 3-fluoro-3-deoxy-D-glucose (3-FG) as a substrate. METHODS: 3-FG metabolism was monitored by 19F-NMR analysis. Dog lenses were incubated in Dulbecco's modified Eagle's medium containing 10 mM 3-FG. Enzymatic reductase and dehydrogenase activities were spectrophotometrically determined, whereas the analyses of 3-FG metabolites were conducted by 19F-NMR analysis. Aldose reductase (AR) was immunohistochemically localized in dog lens with antibodies raised against dog kidney AR. RESULTS: 19F-NMR spectra indicate that incubation of purified dog lenses AR with 3-FG results in the formation of 3-fluoro-3-deoxy-D-sorbitol (3-FS) and that incubation of dog liver sorbitol dehydrogenase (SDH) with 3-FS results in the formation of 3-fluoro-3-deoxy-D-fructose (3-FF). This confirms that 3-FG is metabolized to 3-FF by the polyol pathway enzymes. The affinity (Km) of AR for 3-FG is approximately 20-fold better than that for D-glucose, whereas the Km of SDH for 3-FS was fourfold less than for D-sorbitol. 3-FG in cultured dog lenses is metabolized primarily to 3-FS; however, small amounts of 3-FF and 3-fluoro-3-deoxy-D-gluconic acid (3-FGA) are also formed. 3-FS formation was reduced by the AR inhibitor AL 1576, and 3-FF formation was eliminated by the SDH inhibitor CP-166,572. In dog lens epithelial cells cultured with 3-FG, only 3-FS is formed. Similarly, only 3-FS is formed when lens capsule containing primarily epithelial lens contaminated with superficial epithelial cells was incubated in 3-FG. Similar incubation of the remaining cortex resulted primarily in the formation of 3-FS and 3-FGA. This enzymatic distribution was confirmed by spectrophotometric activity analysis and the immunohistochemical localization of AR. CONCLUSIONS: The data confirm that flux through the polyol pathway primarily results in sorbitol accumulation. The absence of fructose and gluconic acid from cultured lens epithelium suggests that the epithelial cells primarily contain AR, whereas differentiated fiber cells also contain SDH and glucose dehydrogenase.

Multiple pre-neoplastic events and clonal selection of radiation induced mouse thymic lymphomas shown by TCR gene rearrangements.

After split-dose irradiation, pre-lymphoma cells develop from a tumor-specific surface antigen TL-2+ thymocyte subpopulation. To analyze the clonality of pre-lymphoma cells, various numbers of TL-2+ thymocytes from a single irradiated mouse were intra-thymically injected to Thyl congenic recipient mice. The incidence of donor type thymic lymphoma(s) was subsequently examined in a group of recipient mice. We chose several lymphomas derived from a single donor mouse and analyzed the TCR gene rearrangements and V(D)J junctional diversity as genetic markers of clonality. These results indicate multiple initial neoplastic events and clonal selection into lymphoma.

Retinal vessel changes in galactose-fed dogs.

BACKGROUND: Retinal lesions similar to those in human early-stage diabetic retinopathy have been reported to occur in dogs fed galactose for long periods. Investigations of retinal changes, however, have been limited to studies of the intact retinal vasculature isolated by trypsin digestion. OBJECTIVE: To document the onset and progression of retinal lesions in galactose-fed dogs by the common clinical techniques of fundus color photography and fluorescein angiography. METHODS: Fourteen 6-month-old male beagles made aphakic in 1 eye were divided into a control group (4 dogs), receiving a diet containing 30% cellulose, and a galactosemic group (10 dogs), receiving a diet containing 30% galactose. The progression of retinal changes in these dogs was periodically monitored by color fundus photography and fluorescein angiography. RESULTS: Dogs fed a 30% galactose diet for 28 to 41 months were observed by fluorescein angiography and color fundus photography to develop, in order of frequency, microaneurysms, retinal hemorrhages, intraretinal microvascular abnormalities, retinal nonperfused areas, and varicose and serpiginous veins. These findings are similar to the early clinical retinal changes observed in humans with diabetes. CONCLUSION: These results confirm that galactosemic dogs are an appropriate and suitable animal model for investigating human diabetic retinopathy.

Effects of prostaglandin D2, lipoxins and leukotrienes on sleep and brain temperature of rats.

Prostaglandin (PG) D2 and four lipoxygenase-derived eicosanoids [lipoxins (LX) A4 and B4, and leukotrienes (LT) C4 and D4] were examined for their effects on sleep and brain temperature in freely-behaving rats. In the first series of experiments, PGD2 was infused into the third ventricle at four different locations between 23:00 and 05:00. In a location apposed to the medial preoptic area (MPO), PGD2 at doses 1, 10 and 100 pmol/min, increased the slow wave sleep (SWS) by 23% (p < or = 0.01), 35% (p < or = 0.05) and 44% (p < or = 0.01), respectively, during the infusion period. In the second series of experiments, LXs and LTs were infused at the location apposed to MPO. Significant increases in SWS were detected with LXA4 at 100 pmol/min (14%, p < or = 0.05), LXB4 at 100 pmol/min (20%, p < or = 0.05), and LTD at 10 pmol/min (17%, p < or = 0.05). An increase in paradoxical sleep (PS) was produced by PGD2 at 1 and 10 pmol/min infusion (p < or = 0.05), but not by any of the lipoxygenase-derived eicosanoids examined. PGD2 also elevated the mean brain temperature during infusion by 0.2 degrees C and 0.9 degrees C at infusion doses 10 and 100 pmol/min, respectively. But PGD2 infusion at 1 pmol/min did not elevate the brain temperature. LXs (excluding LXB4 at 100 pmol/min) and LTs did not alter the brain temperature significantly at the tested doses. We conclude that PGD2 is the most effective sleep promoter among the eicosanoids examined so far.

Quantitative monitoring of circulating Epstein-Barr virus DNA for predicting the development of posttransplantation lymphoproliferative disease.

Epstein-Barr virus (EBV)-DNA was quantitatively measured to assess posttransplantation virus reactivation by real-time polymerase chain reaction (PCR). In the first retrospective analysis of a 7-year-old boy with lymphoproliferative disease (LPD) after an unrelated cord blood transplantation, serum EBV-DNA progressively increased to 4 x 10(5) copies/mL. EBV load was then prospectively monitored in peripheral blood from posttransplantation patients. The second case was an 8 year-old boy with aplastic anemia who received a CD34+ cell transplantation. This patient died of LPD with the progression of pulmonary nodules. EBV-DNA increased to 4 x 10(4) copies/mL after the control of cytomegalovirus reactivation. On the other hand, EBV-DNA was undetectable (<200 copies/mL) in the series of all 58 samples from 10 patients who did not develop LPD after hematopoietic stem cell transplantation. Sequential monitoring of circulating EBV-DNA by quantitative PCR may be a useful indicator for predicting the development of posttransplantation LPD.

Intravenous administration of inorganic selenium compounds, inhibitors of prostaglandin D synthase, inhibits sleep in freely moving rats.

Prostaglandin (PG) D2 has been postulated to be an endogenous sleep-promoting factor. Biosynthesis of PGD2 is catalyzed by PGD synthase (prostaglandin-H2 D-isomerase, EC 5.3.99.2), the activity of which is inhibited by inorganic selenium compounds such as SeCl4 and Na2SeO3. We recently examined the effect of intracerebroventricular administration of these selenium compounds on sleep in rats, and demonstrated time- and dose-dependent sleep inhibition. To establish whether this effect of selenium is also produced when the compound is administered systemically, we devised a procedure for intravenous catheterization and examined the effect of these selenocompounds on sleep-wake activity in freely moving rats (n = 35). Each test compound was administered into the inferior vena cava continuously between 11.00 and 17.00 h on the experimental day. SeCl4 time- and dose-dependently inhibited sleep at infusion rates of 5, 7.5, 10 and 20 nmol/microliters per min. During the SeCl4 infusion at 20 nmol/microliters per min, slow-wave sleep and paradoxical sleep were reduced to 63% and 50% of their respective baseline values. Na2SeO3 exhibited a similar sleep inhibition, though Na2SO3 was ineffective. Infusion of SeCl4 at 10 nmol/microliters per min or below produced no consistent changes in the mean brain temperature, or food and water intake during the infusion period. During the nocturnal period subsequent to SeCl4 infusion, sleep was increased by a rebound phenomenon, while a decrease in brain temperature and inhibition of food and water intake dose-dependently occurred. We conclude that systemic administration of these PGD synthase inhibitors has a sleep-reducing potency.

Correlation between erythrocyte aldose reductase level and human diabetic retinopathy.

AIM: To examine the relation between aldose reductase (AR) and the development and progression of diabetic retinopathy by comparing the erythrocyte AR levels with the prevalence of diabetic retinopathy in NIDDM patients. METHODS: A clinic based cross sectional study was used. 611 NIDDM patients and 73 controls were enrolled. Erythrocyte AR levels were determined by ELISA. These AR levels were then correlated with patient age, duration of diabetes, and HbA(1c) levels. AR levels were also correlated with the prevalence of diabetic retinopathy in the entire NIDDM patient group and in three subgroups formed by separating the NIDDM patients by their duration of diabetes. The prevalence of diabetic retinopathy significantly increased with increased erythrocyte AR levels in patients with duration of diabetes of less than 10 years. A similar, but non-significant correlation between the prevalence of retinopathy and increased erythrocyte AR levels was observed in patients with diabetes duration of 10-20 and >/=20 years. RESULTS: The prevalence of diabetic retinopathy increased with increased erythrocyte AR levels in NIDDM patients with a duration of diabetes of less than 10 years. CONCLUSION: It was suggested that the inhibition of AR in patients with early NIDDM might be beneficial in reducing the development of diabetic retinopathy.

Bone marrow-thymus interactions during thymic lymphomagenesis induced by fractionated radiation exposure in B10 mice: analysis using bone marrow transplantation between Thy 1 congenic mice.

Bone marrow transplantation (BMT) experiments were conducted using B10.Thy 1 congenic mice to explore the nature of bone marrow-thymus interactions during thymic lymphomagenesis induced by fractionated whole-body X-irradiation (FX). BMT from normal Thy 1 congenic donors into FX-treated recipients one day after FX-treatment resulted in the suppression of tumor development; the suppression being exponentially proportional to the increasing number of bone marrow cells injected. The suppression of tumor development by BMT was shown to be due to prevention of the appearance of prelymphoma cells. BMT from FX-treated donors, which are deficient in pre T cells, into lethally (9 Gy) irradiated Thy 1 congenic recipients resulted in the development of high incidence of thymic lymphomas most of which (approximately 76%) were host-derived, whereas no lymphomas were recovered from the recipients of normal bone marrow. These results suggest that intrathymic T cell precursors which initially repopulate the depleted thymus are prone to undergo preneoplastic changes in the absence of recruitment of more primitive T cell precursors (pre T cells) from the bone marrow but they undergo normal differentiation when large number of pre T cells are available. It was concluded that primary cause of the FX-induced thymic lymphomagenesis was a shortage in supply of pre T cells from the bone marrow to the depleted thymus, which caused differentiation arrest of the progeny of regenerating intrathymic T cell precursors, followed by development of prelymphoma cells that eventually evolve into autonomous lymphoma cells within the thymus.

Characterization of thymic prelymphoma cells that develop during radiation-induced lymphomagenesis in B10 mice.

An intrathymic (i.t.) injection assay on B10.Thy-1 congenic mice was used to demonstrate that thymic prelymphoma cells developed first within mouse thymus 4 to 8 days after split-dose irradiation and were present in more than 63% of the test donor mice thymuses examined 21 and 31 days after irradiation. For the characterization of these thymic prelymphoma cells, thymocytes from B10.Thy-1.1 mice sampled 1 mo after irradiation were stained with J11d mAb and mAb against TL-2 (thymus-leukemia) antigen which is not expressed on normal thymocytes of the B10.Thy 1.2 and B10.Thy 1.1 strains but does appear on thymocytes of split-dose irradiated mice. These cells were sorted into subpopulations, samples of which were injected into recipient thymuses to determine which subpopulations contained thymic prelymphoma cells. Results showed that the prelymphoma cells were located in the J11d+TL-2+ cells. These prelymphoma cells were further characterized phenotypically as to their expression of the CD4 and CD8 antigens, which demonstrated that the thymic prelymphoma cells were present in the CD4-CD8- and CD4-CD8+ thymocyte subpopulations mainly and in the CD4+CD8+ subpopulation. The experiments on i.t. injection of a graded quantity of TL-2+ thymocytes from individual mice suggest that not all TL-2+ cells undergo neoplastic initiation and that prelymphoma cells may develop infrequently from one or more TL-2+ cells by genetic or epigenetic changes.