Inhibition of tumor necrosis factor and subsequent endotoxin shock by pirfenidone

Tumor necrosis factor-alpha (TNF) is an extremely potent cytokine which is involved in the pathogenesis of a number of diseases. Interruption of its synthesis can result in a reduction of inflammation and subsequent pathology. A new experimental drug pirfenidone (5-methyl-L-phenyl-2-(1H)-pyridone, trade name: Deskar) has been reported to have beneficial effects for the treatment of certain fibrotic diseases. The present study describes the inhibition of TNF in vitro as well as the inhibition of circulating TNF in vivo by pirfenidone. Isolated, thioglycollate-induced peritoneal macrophages (Mphi) from C57BL/6 mice were exposed to either lipopolysaccharide (LPS) or mannosylated bovine serum albumin then incubated with 0.1-0.9 mg/ml of pirfenidone. This substance inhibited the production of TNF in a dose-dependent manner as measured by ELISA. One i.p. injection of either 100 or 200 mg/kg pirfenidone inhibited the induction of circulating TNF following a single i.v. injection of LPS. Endotoxin shock was induced in mice using an i.p. injection of galactosamine and LPS. The higher dose of pirfenidone (200 mg/kg) completely inhibited shock and subsequent mortality. Lower doses of pirfenidone or administration either prior to or post challenge only partially inhibited symptoms. These results indicate that pirfenidone is able to inhibit both TNF induction and subsequent endotoxin shock. Additional studies are warranted to establish this drug as a potential treatment for diseases where TNF plays a major role.     

Phenotype, function, and in vivo migration and survival of allogeneic dendritic cell progenitors genetically engineered to express TGF-beta

BACKGROUND: Administration of donor bone marrow (BM)-derived dendritic cell (DC) progenitors (DCp) that are major histocompatibility complex (MHC) class II+ but costimulatory molecule (CD40, CD80, CD86)-deficient can prolong mouse heart allograft survival This is associated with microchimerism and inhibition of antidonor cytotoxic T lymphocyte (CTL) activity. Genetic modification of these donor antigen-presenting cells to express an immunosuppressive molecule(s) may enhance their in vivo survival and potential tolerogenicity. METHODS: The surface phenotype of B10(H-2b) DCp before and after gene transfer using replication-deficient adenoviral (Ad) vectors was determined by monoclonal antibody (mAb) staining and flow cytometry. Transforming growth factor-beta (TGF-beta) production was quantitated by enzyme-linked immunosorbent assay. Allostimulatory activity of the gene-transduced DCp was ascertained by mixed leukocyte reaction (MLR) and CTL induction. To assess their in vivo migratory activity and survival, the transduced cells were injected subcutaneously into one hind footpad of C3H (H-2k) mice. Tissues (draining popliteal lymph nodes [LN], spleens, and thymi) were removed 1, 2, 7, and 14 days later and stained for donor MHC class II using anti-LA(b) mAb in an immunohistochemical procedure. The mean number of IAb+ cells per unit area was determined. RESULTS: Transduction with a control Ad vector (Ad-LacZ) at 50 multiplicity of infection slightly increased CD40 and CD86 expression and up-regulated the poor allostimulatory activity of the DCp assessed by MLR and CTL responses. These effects on function were negated in Ad-TGF-beta1-transduced cells. After their injection into mouse footpads, the gene-transduced IAb+ cells were observed in maximal numbers in the popliteal LN at day 1 and in marginal zones and T-dependent areas of spleens (peak at day 7) but were rare in thymi. Transduction with Ad-LacZ reduced the numbers of IAb+ cells identified in both LN and spleens at all time points postinjection, suggesting that the vector alone affected DC life span in allogeneic recipients. TGF-beta1 transgene expression not only fully prevented the reduction in DC induced by Ad transduction alone, but also increased numbers and prolonged the survival of donor cells in the spleen, as shown by a two-to fivefold increase in IAb+ cells at days 2-14 compared with control (Ad-LacZ-transduced) DC. CONCLUSION: BM-derived DCp can be transduced efficiently to express TGF-beta1 using an Ad vector. They exhibit very poor allostimulatory activity and similar migration characteristics in vivo to unmodified DCp. Survival of TGF-beta gene-transduced DC, however, is enhanced significantly compared with unmodified and (especially) control Ad-LacZ gene-transduced DC. Genetic engineering of donor DC to express the immunosuppressive molecule TGF-beta promotes their survival in allogeneic hosts and may potentiate their previously reported tolerogenicity.     

Diuretic-based treatment and cardiovascular events in patients with mild renal dysfunction enrolled in the systolic hypertension in the elderly program

BACKGROUND: It is expected that the treatment of hypertension in patients with renal disease decreases the risk of cardiovascular events, but the evidence in these patients is lacking. OBJECTIVE: To assess the effect of diuretic-based treatment on cardiovascular events in patients with isolated systolic hypertension and renal dysfunction. METHODS: A total of 4336 persons aged 60 years and older with systolic blood pressures of 160 mm Hg and higher and diastolic blood pressures of less than 90 mm Hg were randomly assigned to receive either placebo or chlorthalidone (12.5-25.0 mg/d), with the addition of atenolol (25-50 mg/d) or reserpine (0.05-0.10 mg/d) if needed, and observed for 5 years. The risk of first-occurring cardiovascular events, including stroke, transient ischemic attack, myocardial infarction, heart failure, coronary artery bypass surgery, angioplasty, aneurysm, endarterectomy, sudden death, or rapid death, was stratified according to baseline serum creatinine levels (35.4-84.0, 84.1-101.6, 101.7-119.3, and 119.4-212.2 micromol/L [0.4-0.9, 1.0-1.1, 1.2-1.3, and 1.4-2.4 mg/dL]). RESULTS: Systolic blood pressure reduction was not affected by baseline serum creatinine levels. Active treatment did not affect the risk of serum creatinine levels becoming elevated during follow-up. The risk of hypokalemia with active treatment decreased significantly with increasing baseline serum creatinine levels. In the 4 baseline serum creatinine groups, the relative risk (95% confidence interval) of cardiovascular events developing with active treatment was 0.73 (0.54-0.97), 0.63 (0.49-0.82), 0.62 (0.44-0.87), and 0.59 (0.38-0.91). The results were similar for the outcomes of stroke or coronary artery events and in analyses stratified by sex or age. CONCLUSION: Diuretic-based treatment of patients with isolated systolic hypertension prevents the development of cardiovascular events in older persons with mild renal dysfunction.     

A prospective study of physical activity and prostate cancer in male health professionals

Because the role of exercise in prostate cancer is unclear, we examined the relationship between leisure time physical activity and risk of prostate cancer in the Health Professionals Follow-up Study, a prospective cohort study of male health professionals in the United States. In 1986, 47,542 men 40-75 years of age and free of cancer responded to a mailed questionnaire that included an assessment of physical activity. The reported average time per week spent on each of a variety of nonoccupational activities was multiplied by its typical energy expenditure requirements expressed in metabolic equivalents (METs) and summed to yield a total weekly MET-hour score. We also examined MET-hours from all vigorous activities, defined as those requiring energy expenditures of six or more METs, and nonvigorous activities. From 1986 until January 31, 1994, we identified 1362 incident cases of total prostate cancer (excluding stage A1), 419 advanced (extraprostatic) cases, and 200 metastatic cases. No relationship with total or advanced prostate cancer was evident for total, vigorous, and nonvigorous physical activity. For metastatic prostate cancer, we also found no linear trends for these activities, but did observe a significantly lower risk in the highest category of vigorous activity (multivariate relative risk = 0.46; 95% confidence interval = 0.24-0.89 for > 25 versus 0 MET-hours), controlling for age, vasectomy, history of diabetes, height, smoking, and dietary factors. This highest category included 15% of the population and reflects at least 3 h/week of participation in vigorous activities. Differences in disease surveillance according to activity level could not account for our findings. The results from this cohort indicate that physical activity is unlikely to influence the incidence of total prostate cancer appreciably; however, the suggestion of a lower risk of metastatic prostate cancer in men engaging in high levels of vigorous activities warrants further study.     

A four-hour topotecan infusion achieves cytotoxic exposure throughout the neuraxis in the nonhuman primate model: implications for treatment of children with metastatic medulloblastoma

The purpose of this study was to define the length of topotecan (TPT) i.v. infusion necessary to attain a cytotoxic exposure for medulloblastoma cells throughout the neuraxis. In vitro studies of human medulloblastoma cell lines (Daoy, SJ-Med3) were used to estimate the length and extent of TPT systemic exposure associated with inhibition of tumor cell growth or the exposure duration threshold (EDT). We evaluated TPT systemic and cerebrospinal fluid (CSF) disposition in six male rhesus monkeys (8-12 kg) that received TPT 2.0 mg/m2 i.v. as a 30-min or 4-h infusion. Plasma and CSF samples were assayed for TPT lactone by high-performance liquid chromatography, and the CSF exposures were compared with the estimated EDT. Results of the in vitro studies defined an EDT as a TPT lactone concentration of > 1 ng/ml for 8 h (IC99) daily for 5 days. The mean +/- SD for systemic clearance (CL(SYS)), penetration into fourth ventricle (%CSF(4th)), and penetration into lumbar space (%CSF(LUM)) were similar for the 30-min and the 4-h infusions. At a TPT lactone systemic exposure (AUC(PL)) of 56.7 +/- 19.9 ng/ml x h, time above 1 ng/ml in the fourth ventricle was 1.4-fold greater for a 4-h infusion compared with a 30-min infusion. At a TPT lactone AUC(PL) of 140 ng/ml x h, the 4-h infusion achieved the desired TPT exposure throughout the neuraxis (lateral and fourth ventricles and lumbar space), whereas the 30-min infusion failed to achieve it in the lumbar space. In conclusion, prolonging TPT i.v. infusion from 30-min to 4-h at a targeted AUC(PL) achieves the EDT throughout the neuraxis and represents an alternative method of TPT administration that will be tested prospectively in patients with high-risk medulloblastoma.     

Dietary vitamin A intake in relation to child growth

Protective effects of calcium antagonists, chlorpromazine (CPZ) and nimodepine (NI-MO), on cadmium-induced toxicity were investigated. After giving CdCl2 (0.44 mg Cd/kg, i.p.), CPZ (5 mg/kg, i.p.) or NIMO (8 mg/kg, p.o.) were administered every day to Sprague-Dawley (S.D.) rats for a week. Then, urinary N-acetyl-beta-D-glucosaminidase (NAG), urinary cadmium and blood cadmium were measured. The accumulation of cadmium in the kidney cortex, content of renal calmodulin, hemoglobin and the ultrastructural damage of proximal convoluted tubules of rats were examined three weeks after the last administration. Results indicated that the calcium antagonists partly protected against toxic effects induced by cadmium in different manners. These data provide further evidence for the new hypothesis that the cross effect of cadmium and calcium in calmodulin regulated systems may be responsible for the mechanism of cadmium intoxication. The results suggested that the calcium antagonists could be a new and promising approach in the therapy of heavy metal-induced diseases.     

Late presentation of cryptorchidism: the etiology of testicular re-ascent

PURPOSE: We reviewed the records of 21 boys who had 23 previously documented descended testes that reascended and who underwent orchiopexy during a 2-year period. MATERIALS AND METHODS: We retrospectively reviewed a 2-year experience in 103 boys (115 undescended testes) who underwent orchiopexy in 1988 and 1989. RESULTS: In our 2-year experience 21 of the 103 boys with undescended testes had multiple recorded confirmations of testicular descent in the past. Of the boys 40% had previously been examined in the office or with general anesthesia by a pediatric urologist or pediatric surgeon for another reason, and 40% had a nurse or physician parent. Surgery was performed at ages 5 to 14 years, an average of 2 years after the initial presentation with reascent. Human chorionic gonadotropin was unsuccessful in causing testicular descent. There was no correlation with a patent processus vaginalis and no association with adhesions. The testis was located in the superficial inguinal pouch in the majority of patients, and the gubernacular attachment was in an abnormal location in all and ectopic in half of the cases. CONCLUSIONS: Our observations confirm that the etiology of this condition is a missed diagnosis at a younger age. The testis is undescended but almost completely descended. With somatic growth the distance between the terminal portion of the gubernaculum of the apparently descended testis and the scrotum increases, making the diagnosis more obvious. The potential for this condition makes it mandatory that intrascrotal testicular location be confirmed by periodic physical examination through puberty.     

What is the marginal cost for marginal risk in cardiac surgery?

BACKGROUND: It has been shown that postoperative length of stay (LOS) correlates highly with mortality risk for cardiac surgical procedures. Similar correlations have been found for charges with LOS and costs with risk. METHODS: Postoperative LOS and risk scores were obtained, tabulated, and compiled into the five original Parsonnet risk groups for 2,589 patients who underwent cardiac operations from 1992 through 1996 at one hospital. The correlation of the group mean LOS with the group mean risk was tested. RESULTS: The correlation coefficient was 0.9827; 96.58% of the variance was removed using risk to predict LOS. A calculation of the difference in cost for difference in risk for cohorts of patients is developed. CONCLUSIONS: The high correlation of mean LOS with mean risk permits calculation of marginal cost for marginal risk based on clinical data. The marginal cost is equal to the difference in variable costs for cohorts.     

Molecular modeling of the interaction of diagnostic radiopharmaceuticals with receptor proteins: m2 antagonist binding to the muscarinic m2 subtype receptor

Models of the m2 muscarinic receptor have been built and acetylcholine and an antagonist of the quinuclidinyl benzilate family docked to the putative active site. We have incorporated aspects of homology, site-directed mutagenesis studies and structure-activity studies of specific lead compounds in the construction of our receptor models with a primary focus on the structure of the binding sites. We have observed a deep pocket binding of 5-BrQNT, suggesting a plausible explanation for the observation that agonists and antagonists do not bind competitively. The results of these computational studies are interpreted within the context of the observed in vitro results. Our goal is to assist in the development of subtype receptor selective radiopharmaceuticals for use in PET and SPECT.