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Immunohistochemical measurement of endothelial cell apoptosis and proliferation in formalin-fixed, paraffin-embedded human cancer tissue.

There is a need for simple, reproducible methodology for measurement of endothelial cell (EC) apoptosis and proliferation in formalin-fixed, paraffin-embedded (FFPE) human tissue obtained in clinical trials of potential anti-angiogenic agents. Therefore, we developed colorimetric, dual-label immunohistochemical techniques for use on FFPE tissue, based on the use of single-stranded (ss) DNA and Ki-67 as markers of EC apoptosis and proliferation, respectively. Digital image analysis was used to obtain the total tumour microvessel density (MVD), from which the EC apoptosis index (AI) and proliferation index (PI) were derived manually as the number of positive ECs per vessel. Immunohistochemical measurement of EC apoptosis and proliferation was validated on human colorectal cancer liver metastases from a randomized, placebo-controlled trial of the selective cyclooxygenase-2 inhibitor rofecoxib. Proliferating and apoptotic ECs clustered in discrete areas of the tumour vasculature. ECAI (median [inter-quartile range, IQR] 0.0018 [0.0003-0.0064]) and ECPI (median [IQR] 0.0043 [0.002-0.014]) values were low and highly variable in tumours from both placebo- and rofecoxib-treated patients. Our novel dual-label immunohistochemical methods will be generally applicable in FFPE human cancer tissue and should prove invaluable for measuring the anti-angiogenic activity of experimental therapies in clinical trials. The low absolute level of and variability in EC apoptosis and proliferation detectable in human colorectal cancer liver metastases indicates that similar intervention studies using these end-points will need to ensure adequate size in order to be able to detect anti-angiogenic activity by immunohistochemical methods.

Apoptosis↗

Influence of different types of effectors on the kinetic parameters of suicide inactivation of catalase by hydrogen peroxide.

The effects of cyanide and azide ions (class A), sodium-n-dodecyl sulphate (SDS) and 2-mercaptoethanol (class B), 3-aminotriazole (class C) and NADPH (class D) on the initial activity (ai), inactivation rate constant (ki) and the partition ratio (r) of bovine liver catalase reaction with its suicide substrate, hydrogen peroxide, were studied in 50 mM sodium phosphate buffer, pH 7.0 at 27 degrees C. The above kinetic parameters were determined by processing the progress curve data. In class A, which contains fast and reversible inhibitors of catalase, a proportional decrease in ai and ki was observed by inhibitors, so that the r remained constant. In class B, which contains slow and irreversible inactivators, a decrease in ai and constancy of ki and r were observed when catalase was incubated in the presence of such inactivators for a determined time. In class C, containing effector which can combine with intermediate compound I, ai was relatively unchanged but an increase in ki and a decrease in r were observed. In class D, containing effector which reduces compound I to ferricatalase, ai was not affected significantly but some decrease in ki was detected which was linked with an increase in r. These results demonstrate that different classes of effectors affect the determined kinetic parameters of catalase in various ways. Thus, determination of such parameters by simple kinetic experiments can be carried out for classification of the agents which have an effect on the kinetics of catalase.

Animals↗

A randomized trial of adoptive immunotherapy with tumor-infiltrating lymphocytes and interleukin-2 versus standard therapy in the postoperative treatment of resected nonsmall cell lung carcinoma.

BACKGROUND: A previous pilot study from our group suggested that: (1) adoptive immunotherapy (A1) with tumor-infiltrating lymphocytes (TIL) and recombinant interleukin-2 (rIL-2) may be applied with safety to more than 80% of the patients who had surgery for Stage III nonsmall cell lung carcinoma (NSCLC); and (2) AI could be useful in patients with locally advanced disease. The present randomized study was planned to assess the efficacy of AI in the postoperative treatment of Stage II, IIIa, or IIIb NSCLC: METHODS: TIL were expanded in vitro from tissue samples obtained from the surgically removed specimens of 131 patients. Eighteen cultures yielded no growth of TIL. The remaining 113 patients were stratified according to disease stage and randomized to receive AI or standard chemoradiotherapy. TIL were infused intravenously 6 to 8 weeks after surgery, rIL-2 was administered subcutaneously at escalating doses for 2 weeks, and then at reduced doses for 2 weeks and then for 2 to 3 months. RESULTS: Three-year survival was significantly better (P < 0.05) for patients who underwent AI than for controls. AI was of no benefit to patients with Stage II NSCLC, potentially useful to patients with Stage IIIa NSCLC (P = 0.06), and significantly advantageous to patients with Stage IIIb (T4) NSCLC (P < 0.01). For patients with Stage III NSCLC, local relapse (but not distant relapse) was significantly reduced following AI (P < 0.05). CONCLUSIONS: AI should be considered when designing future adjuvant therapy protocols for the treatment of NSCLC:

Antineoplastic Agents↗

Effects of trehalose and sucrose, osmolality of the freezing medium, and cooling rate on viability and intactness of bull sperm after freezing and thawing.

The influence of the presence of trehalose or sucrose, the osmolality of the freezing medium, and the cooling rate on success of cryopreservation of bull sperm were investigated. Bull semen was frozen at four different cooling rates varying from 40 to 300 degrees C/min in standard Tris-egg yolk medium and in hypertonic or isotonic media containing 0.2 M trehalose or sucrose. Sperm motility, H33258 exclusion, and acrosome morphology were evaluated. In the hypertonic media the motility was almost completely inhibited, but could partly be restored by returning to isotonic conditions. Medium composition and cooling rate had significant effects, with a strong interaction of medium x cooling rate. The optimal cooling rate was found to be between 76 and 140 degrees C/min. At the highest cooling rate, both the presence of the sugars and the high osmolality of the hypertonic media conferred significant protection against fast-cooling damage, sucrose being significantly better than trehalose. At all other cooling rates the medium differences were less pronounced, but the isotonic sugar media were generally superior to standard medium as to preservation of acrosome intactness and H33258 exclusion. This indicates that the isotonic sugar media could enable some improvement of cryopreservation of bull semen over the currently used Tris-egg yolk medium. Further improvement of sperm survival at the AI station should be possible by implementation of controlled rate freezing, using a cooling rate in the optimal range between 76 and 140 degrees C/min.

Animals↗

Hypoglycaemic effect of the lyophilised aqueous extract of Ajuga iva in normal and streptozotocin diabetic rats.

The purpose of this study was to examine the hypoglycaemic effect of the lyophilised aqueous extract of the whole plant of Ajuga iva (L.) Schreber (Labiatae) in normal and streptozotocin-induced diabetic rats. Single and repeated oral administration of the extract of Ajuga iva L (AI) at a dose of 10 mg/kg produced a slight and significant decrease in plasma glucose levels in normal rats 6 h after administration and after 3 weeks of treatment. AI reduced plasma glucose levels of streptozotocin diabetic rats from 337+/-9.3 to 102.2+/-17.7 mg/dl after 6 h of oral administration (P<0.001). Repeated oral administration of AI to streptozotocin diabetic rats significantly decreased the plasma glucose levels after 1 week of treatment (112+/-14.4 mg/dl at 1 week vs 337+/-9.3 mg/dl at the baseline values, (P<0.001). It continuously decreased thereafter and showed a rapid normalisation after 1 week of AI treatment. It is concluded that these results demonstrated that the water extract of the whole plant of AI possess a strong hypoglycaemic effect in diabetic rats, and support therefore, its traditional use in diabetes mellitus control.

Administration, Oral↗

Fundamentals and recent development in cryopreservation of bull and boar semen.

This paper describes some of the effects of cryopreservation on living sperm, and some recent results for bull and boar semen. During freezing and thawing of semen, the sperm can be damaged by the rapid and dramatic changes in the physicochemical conditions during cooling and ice formation. The rate and extent of these changes, and their impact on the cells, are strongly affected by the cooling rate and the medium composition. For many species, including humans and several farm animals, the optimal cooling rate has been determined, sometimes in combination with the cryoprotectant concentration. Recent results indicate that the cryopreservation of bull semen at the AI station could be improved by using controlled freezing at a cooling rate of about 100 degrees C/min, and by changing the composition of the freezing medium. An interaction between glycerol concentration and cooling rate has been described for boar semen. Current cryopreservation methods for boar semen based on an optimal combinations of these two factors allow consistent sperm survival in the frozen semen of AI boars, with acceptable variation among boars. The fertility results for semen processed in this fashion seem to be adequate for special applications, such as export, or long-term storage.

Animals↗

Drug-induced apoptosis and p53, BCL-2 and BAX expression in breast cancer tissues in vivo and in fibroblast cells in vitro.

BACKGROUND: Chemotherapeutic management of breast cancers is a difficult task as they show significant differences in chemosensitivity. The present study was undertaken to determine the usefulness of the apoptosis-related factors as indicators of tumor sensitivity to 5'-deoxyfluorouridine (5'-DFUR) in breast cancers. METHODS: (1) Forty-six breast cancer patients were randomly assigned to a group in which oral 5'-DFUR (1200 mg/day) was administered for more than 5 days before operation (24 patients) and a control group who received no preoperative chemotherapy (22 patients). Surgical specimens were examined for the frequency of apoptotic cells [apoptotic index (AI)] by a terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling method and for the expression of p53, BCL-2 and BAX by immunohistochemical staining. (2) Normal human diploid fetal lung fibroblast, IMR90 and SV40 transformed IMR90 were exposed to 5-FU. Apoptotic cells were detected by flow cytometry and BCL-2 and BAX mRNAs by real-time quantitative RT-PCR analysis. RESULTS: (1) No significant difference in the AIs or in BCL-2 and BAX scores was observed between the 5'-DFUR-treated and control groups. However, in the p53 negative subgroup (n = 36), AI and BAX scores were higher and BCL-2 scores lower in the 5'-DFUR group than in the control group (P = 0.006, 0.008 and 0.050, respectively). (2) The sensitivity of IMR90 was significantly decreased by SV40 transformation and the 5-FU-induced cytotoxicity was mainly due to induction of apoptosis. The BCL-2/BAX mRNA ratio was decreased in response to 5-FU in IMR90. These results correlated with our clinical data. CONCLUSIONS: Preoperative treatment with 5'-DFUR induced apoptosis and changes in BCL-2 and BAX expression in p53 negative breast cancers. p53 status, AI and the BCL-2/BAX ratio may be useful information for the choice of postoperative chemotherapy for breast cancer.

Antineoplastic Agents↗

Combination of cyclin-dependent kinase and immune checkpoint inhibitors for the treatment of bladder cancer.

BACKGROUND: Perturbation of the CDK4/6 pathway is frequently observed in advanced bladder cancer. We investigated the potential of targeting this pathway alone or in combination with chemotherapy or immunotherapy as a therapeutic approach for the treatment of bladder cancer METHODS: The genetic alterations of the CDK4/6 pathway in bladder cancer were first analyzed with The Cancer Genome Atlas database and validated in our bladder cancer patient-derived tumor xenografts (PDXs). Bladder cancer cell lines and mice carrying PDXs with the CDK4/6 pathway perturbations were treated with a CDK4/6 inhibitor palbociclib to determine its anticancer activity and the underlying mechanisms. The combination index method was performed to assess palbociclib and gemcitabine drug-drug interactions. Syngeneic mouse bladder cancer model BBN963 was used to assess whether palbociclib could potentiate anti-PD1 immunotherapy. RESULTS: Of the 413 bladder cancer specimens, 79.2% harbored pertubations along the CDK4/6 pathway. Palbociclib induced G0/G1 cell cycle arrest but with minimal apoptosis in vitro. In mice carrying PDXs, palbociclib treatment reduced tumor growth and prolonged survival from 14 to 32&#xa0;days compared to vehicle only controls (p&#x2009;=&#x2009;0.0001). Palbociclib treatment was associated with a decrease in Rb phosphorylation in both cell lines and PDXs. Palbociclib and gemcitabine exhibited antagonistic cytotoxicity in vitro (CI&#x2009;>&#x2009;3) and in vivo, but palbociclib&#xa0;significantly enhanced the treatment efficacy of anti-PD1 immunotherapy and induced CD8+ T lymphocyte infiltration in syngeneic mouse models. CONCLUSIONS: The CDK4/6 pathway is feasible as a potential target for the treatment of bladder cancer, especially in combination with immunotherapy. A CDK4/6 inhibitor should not be combined with gemcitabine.

Animals↗

Brasilicardin A, a natural immunosuppressant, targets amino Acid transport system L.

Lymphocytes in T cell activation require extracellular nutrients to provide energy for cellular proliferation and effector functions. Therefore, inhibitors of nutrient transporters are expected to be a new class of immunosuppressant. Here, we report that the molecular target of brasilicardin A (BraA), an immunosuppressive compound, is the amino acid transporter system L. BraA inhibited the cell-cycle progression of murine T cell lymphocyte CTLL-2 cells in G1 phase, and potently inhibited the uptake of amino acids that are substrates for amino acid transport system L. Moreover, BraA stimulated the GCN2 activation and, subsequently, the phosphorylation of eIF2alpha. These results suggest that the immunosuppressive activity of BraA is induced by amino acid deprivation via the inhibition of system L and that the amino acid transporter is a target for immunosuppressant.

Amino Acid Transport System L↗

Minocycline inhibits LPS-induced retinal microglia activation.

Retinal neurodegenerative disease involves an inflammatory response in the retina characterized by an increase in inflammatory cytokines and activation of microglia. The degree of microglia activation may influence the extent of retinal injury following an inflammatory stimulus. Cytokines released by activated microglia regulate the influx of inflammatory cells to the damaged area. Thus, a therapeutic strategy to reduce cytokine expression in microglia would be neuroprotective. Minocycline, a semisynthetic tetracycline derivative, is known to protect rodent brain from ischemia and to inhibit microglial activation. In this study, we activated retinal microglia in culture with lipopolysaccharide (LPS) and attempted to determine whether minocycline could reduce the production of cytokines from activated microglia at both gene and protein levels. Changes in inflammatory cytokines, TNF-alpha and IL-1beta, were measured by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) in the presence or absence of LPS. We also measured the levels of nitric oxide (NO) by the nitrate reductase method under similar conditions. LPS treatment induced a significant upregulation of the mRNA and release of TNF-alpha, IL-1beta, and NO from retinal microglia. Minocycline inhibited these releases. Thus, minocycline might exert its antiinflammatory effect on microglia by inhibiting the expression and release of TNF-alpha, IL-1beta, and NO.

Animals↗

Cytotoxic ent-kaurane diterpenoids from Isodon sculponeata.

Four new ent-kaurane diterpenoids, sculponeatins F-I (1-4), together with six known compounds, sculponeatin E (5), epi-nodosin (6), epi-nodosinol (7), enmein (8), and macrocalyxoformins A and B (9 and 10), were isolated from the leaves of Isodon sculponeata. Also obtained were ursolic acid, 2alpha,3beta-dihydroxy-urs-12-en-28-oic acid, 2alpha,3beta,19alpha-trihydroxy-urs-12-en-28-oic acid, beta-sitosterol, daucosterol, quercetin, pedalitin, rosmarinic acid, caffeic acid and ethyl caffeic acid. Their structures were determined by spectral methods (1D-, 2D-NMR and MS). Some diterpenoids were tested for their cytotoxicity to inhibit three kinds of human tumor cells K562, A549 and T24. Compounds 3, 4, 6, 8, and 10 showed significant inhibitory effect toward K562 with IC(50) values ranging from 3.2 microg/ml to 8.2 microg/ml, while 3 and 6 exhibited potent antitumor activity against T24, but none exhibited cytotoxicity toward the cells of A549.

Antineoplastic Agents, Phytogenic↗

Increased cholesteryl ester transfer protein and changes in lipid metabolism from initiating insulin therapy.

Insulin therapy is often necessary for glycemic control, and its effect on plasma lipids is an important issue with respect to arteriosclerosis. Previous reports suggested that increased cholesteryl ester transfer protein (CETP) appeared in diabetic patients with hyperinsulinemia or given a lot of insulin is atherogenic. We investigated whether insulin always increases CETP and whether increased CETP by insulin is always atherogenic. In 40 patients the amount and activity of CETP were assessed before and 2 weeks after initiation of insulin therapy. After starting insulin, plasma concentrations of total cholesterol, triglycerides, LDL-cholesterol, and remnant lipoprotein cholesterol decreased. No change occurred in HDL-cholesterol. Starting insulin therapy increased the amount and activity of CEIP. No significant correlation was observed between changes in CETP and in lipids including HDL-cholesterol or apolipoprotein concentrations. This is the first prospective study to show increased CETP activity after initiation of insulin therapy. After initiating insulin, CETP increases without accompanying atherogenic changes in lipid metabolism. Based on the changes observed, CETP in itself does not have atherogenicity and the increase, but no excess, of CETP by appropriate insulin therapy cannot be atherogenic.

Apolipoproteins↗

Study of the effects of the implantable contraceptive Norplant on lipid and lipoprotein metabolism. UN Development Programme/UN Population Fund/WHO/World Bank, Special Programme of Research, Development and Research Training in Human Reproduction, Task Force on Long-Acting Systemic Agents for Fertility Regulation.

A 2-year longitudinal study was undertaken to investigate the effects of the implantable contraceptive Norplant on lipid and lipoprotein metabolism. A group of 177 Norplant implants acceptors was recruited in five centers (Bangkok, Jakarta, Mexico City, Singapore, and Stockholm) and monitored during one baseline menstrual cycle and 3, 5, 11, 16, and 22 months after implant insertion. They were compared with a group of 174 copper intrauterine (IUD) device users who had blood sampling performed at comparable time points. Lipid changes were greatest 3 months after implant insertion and a slow reversal of these trends towards baseline was observed during the next 19 months. The main changes observed at 3 months were a 10% drop in total cholesterol, and an 11% drop in high-density lipoprotein (HDL)-cholesterol and apolipoprotein AI levels, together with a 19% decline in serum triglycerides. Variations in low-density lipoprotein (LDL)-cholesterol and apolipoprotein B levels were not significantly different from those observed in the group of IUD users. There was consistency in these findings between centers in that the changes were in the same direction but of different magnitude in different centers. It is concluded that lipid changes induced by Norplant implants will probably not affect the risk of atherosclerotic disease in women who use this contraceptive method.

Adolescent↗

Beneficial effects of topical anti-inflammatory drugs against sulfur mustard-induced ocular lesions in rabbits.

Ocular injuries following sulfur mustard (HD) exposure are characterized by an inflammatory response, observed as eyelid swelling, conjunctivitis, corneal oedema and cellular infiltration starting 1-4 h after exposure, depending on dose. These effects heal partially during the first 1-2 weeks after exposure, with the later appearance of neovascularization, recurrent erosions and recurrent oedema of the cornea (delayed response). We have shown previously that topically applied steroid treatment, administered after HD exposure, attenuated the extent of neovascularization, one of the characteristics of delayed ocular pathology in rabbits. The present study was designed to characterize further the initial inflammatory response and to elucidate the role of anti-inflammatory (AI) drugs as a potential therapy. Rabbit eyes were exposed to HD vapour (390 microg l(-1) for 2 min) and were treated with a topical commercial ophthalmic solution of dexamethasone or diclofenac, starting 1 h post-exposure (four times a day). Inflammation was evaluated by clinical observations, biochemical analysis of aqueous humour and by histology. Sulfur mustard exposure initiated typical clinical ocular symptoms within 4-6 h after exposure. Biochemical analysis of aqueous humour showed that protein content and prostaglandin E (PGE) increased significantly at 6 h and were still high 48 h after HD exposure. Light microscopy evaluation revealed severe damage to the cornea, characterized by epithelial denudation, oedema and cellular infiltration (mostly eosinophiles) in the stroma. Both treatments were effective in alleviating the clinical symptoms and in preventing the HD-induced increase in protein and PGE in the anterior chamber, as well as the cellular infiltration, in the corneal stroma. However, the AI treatments had no therapeutic effect on corneal erosions, and a short delay in epithelial regeneration was noted. It is concluded that AI drugs are potential candidates for the treatment of ocular lesions following HD exposure.

Animals↗

Comparative effects of enalapril, enalaprilic acid and captopril in blocking angiotensin I-induced pressor and dipsogenic responses in spontaneously hypertensive rats.

The role of central angiotensin converting enzyme (ACE), in the maintenance of high blood pressure, was examined in unanesthetized spontaneously hypertensive rats (SHR). Pressor and dipsogenic responses induced by intracerebroventricular (ICV) injections of angiotensin I (AI) were elicited before and 30 min after either captopril (120-800 nanomoles ICV), enalapril (66-460 nanomoles ICV) and enalaprilic acid (70-280 nanomoles ICV). Enalapril was 1.6 (0.7-3.9) and 1.7 (0.9-2.9) times more potent than captopril in inhibiting AI-induced pressor and dipsogenic responses, respectively. Enalaprilic acid was 2.7 (1.1-7.1) and 2.9 (1.9-4.8) times more potent than captopril in inhibiting AI- (ICV administration) induced pressor and dipsogenic responses, respectively. None of the ACE inhibitors, in contrast, reduced the central actions of AII. Basal mean arterial pressure was not reduced by these ACE inhibitors after ICV administration. Administered orally at doses which produced similar hypotensive responses, neither captopril (30 mg/kg) nor enalapril (3 mg/kg) blocked the responses induced by AI given ICV (10 ng). These findings indicate that ACE inhibitors given acutely do not penetrate into the central nervous system sufficiently to block the dipsogenic and pressor responses induced by AI given ICV, and suggest that inhibition of central ACE may not be important to the acute antihypertensive activity of the ACE inhibitors tested.

Angiotensin I↗

Effect of antibiotic-impregnated shunt catheters in decreasing the incidence of shunt infection in the treatment of hydrocephalus.

OBJECT: The majority of shunt infections occur within 6 months of shunt placement and chiefly result from perioperative colonization of shunt components by skin flora. Antibiotic-impregnated shunt (AIS) systems have been designed to prevent such colonization. In this study, the authors evaluate the incidence of shunt infection after introduction of an AIS system in a population of children with hydrocephalus. METHODS: The authors retrospectively reviewed all pediatric patients who had undergone cerebrospinal fluid (CSF) shunt insertion at their institution over a 3-year period between April 2001 and March 2004. During the 18 months prior to October 2002, all CSF shunts included standard, nonimpregnated catheters. During the 18 months after October 2002, all CSF shunts included antibiotic-impregnated catheters. All patients were followed up for 6 months after shunt surgery, and all shunt-related complications, including shunt infection, were evaluated. The independent association of AIS catheter use with subsequent shunt infection was assessed via multivariate proportional hazards regression analysis. A total of 211 pediatric patients underwent 353 shunt placement procedures. In the 18 months prior to October 2002, 208 (59%) shunts were placed with nonimpregnated catheters; 145 (41%) shunts were placed with AIS catheters in the 18 months after October 2002. Of patients with nonimpregnated catheters, 25 (12%) experienced shunt infection, whereas only two patients (1.4%) with antibiotic-impregnated catheters experienced shunt infection within the 6-month follow-up period (p < 0.01). Adjusting for intercohort differences via multivariate analysis, AIS catheters were independently associated with a 2.4-fold decreased likelihood of shunt infection. CONCLUSIONS: The AIS catheter significantly reduced incidence of CSF shunt infection in children with hydrocephalus during the early postoperative period (< 6 months). The AIS system used is an effective instrument to prevent perioperative colonization of CSF shunt components.

Adolescent↗

Fengycin--a novel antifungal lipopeptide antibiotic produced by Bacillus subtilis F-29-3.

Fengycin is an antifungal lipopeptide complex produced by Bacillus subtilis strain F-29-3. It inhibits filamentous fungi but is ineffective against yeast and bacteria. The inhibition is antagonized by sterols, phospholipids and oleic acid, whereas two other unsaturated fatty acids increase the antifungal effect. Fengycin consists of two main components differing by one amino acid exchange. Fengycin A is composed of 1 D-Ala, 1 L-Ile, 1 L-Pro, 1 D-allo-Thr, 3 L-Glx, 1 D-Tyr, 1 L-Tyr, 1 D-Orn, whereas in fengycin B the D-Ala is replaced by D-Val. The lipid moiety of both analogs is more variable, as fatty acids have been identified as anteiso-pentadecanoic acid (ai-C15), iso-hexadecanoic acid (i-C16), n-hexadecanoic acid (n-C16), and there is evidence for further saturated and unsaturated residues up to C18.

Antifungal Agents↗