A randomized clinical trial of continuous versus intermittent dialysis for acute renal failure

BACKGROUND

Acute renal failure (ARF) requiring dialysis in critically ill patients is associated with an in-hospital mortality rate of 50 to 80%. The worldwide standard for renal replacement therapy is intermittent hemodialysis (IHD). Continuous hemodialysis and hemofiltration techniques have recently emerged as alternative modalities. These two therapies have not been directly compared.

METHODS

A multicenter, randomized, controlled trial was conducted comparing two dialysis modalities (IHD vs. continuous hemodiafiltration) for the treatment of ARF in the intensive care unit (ICU). One hundred sixty-six patients were randomized. Principal outcome measures were ICU and hospital mortality, length of stay, and recovery of renal function.

RESULTS

Using intention-to-treat analysis, the overall ICU and in-hospital mortalities were 50.6 and 56.6%, respectively. Continuous therapy was associated with an increase in ICU (59.5 vs. 41.5%, P < 0.02) and in-hospital (65.5 vs. 47.6%, P < 0.02) mortality relative to intermittent dialysis. Median ICU length of stay from the time of nephrology consultation was 16.5 days, and complete recovery of renal function was observed in 34.9% of patients, with no significant group differences. Despite randomization, there were significant differences between the groups in several covariates independently associated with mortality, including gender, hepatic failure, APACHE II and III scores, and the number of failed organ systems, in each instance biased in favor of the intermittent dialysis group. Using logistic regression to adjust for the imbalances in group assignment, the odds of death associated with continuous therapy was 1.3 (95% CI, 0.6 to 2.7, P = NS). A detailed investigation of the randomization process failed to explain the marked differences in patient assignment.

CONCLUSIONS

A randomized controlled trial of alternative dialysis modalities in ARF is feasible. Despite the potential advantages of continuous techniques, this study provides no evidence of a survival benefit of continuous hemodiafiltration compared with IHD. This study did not control for other major clinical decisions or other supportive management strategies that are widely variable (for example, nutrition support, hemodynamic support, timing of initiation, and dose of dialysis) and might materially influence outcomes in ARF. Standardization of several aspects of care or extremely large sample sizes will be required to answer optimally the questions originally posed by this investigation.

Influence of tobacco marketing and exposure to smokers on adolescent susceptibility to smoking

BACKGROUND

Today the uptake of smoking is primarily an adolescent pursuit. Awareness of tobacco advertising and promotion is high, and evidence suggests that it plays a role in adolescent smoking uptake.

PURPOSE

We evaluated the influence of tobacco advertising and promotion and exposure to smokers on never-smoking adolescents' susceptibility to smoking.

METHODS

We used data on 3536 adolescent never smokers (those who had never even puffed on a cigarette) from the 1993 California Tobacco Survey. That survey questioned adolescents about smoking history and inclinations. For this analysis, we defined as susceptible to smoking those never smokers who said on the survey that they could not rule out independently deciding to try a cigarette soon or smoking one offered by a friend. Also for this analysis, we devised two indices: 1) a 5-point index of an individual's receptivity to tobacco advertising as determined by the number of positive responses to five survey items (recognition of advertising messages, having a favorite advertisement, naming a brand he/she might buy, owning a tobacco-related promotional item, and willingness to use a tobacco-related promotional item) and 2) an index classifying an individual's reported exposure to family and peer smoking into one of four levels. Using logistic regression, we assessed the independent importance of our indices in predicting susceptibility to smoking after adjustment for sociodemographic variables, including age, sex, and race/ethnicity, and for perceived school performance. Tests of statistical significance were two-sided.

RESULTS

Receptivity to tobacco advertising and exposure to smokers were independently associated with susceptibility to smoking, but the relationship appeared stronger for receptivity to advertising. Adolescents exposed to family members and peers (n = 489) who smoked were 1.89 (95% confidence interval [CI] = 1.30-2.74) times as likely to be susceptible, whereas adolescents who scored 4 or more on the Index of Receptivity to Tobacco Marketing (n = 361) were 3.91 (95% CI = 2.38-6.42) times as likely to be susceptible as those who scored 0. Even adolescents who scored 2 (n = 1090) were 2.03 (95% CI = 1.31-3.15) times as likely to be susceptible. There was no interaction effect between score on the Index of Receptivity to Tobacco Marketing and exposure to smokers.

CONCLUSION

Our results support the hypothesis that tobacco marketing may be a stronger current influence in encouraging adolescents to initiate the smoking uptake process than exposure to peer or family smokers or sociodemographic variables including perceived school performance.

National trends in the epidemiology of prostate cancer, 1973 to 1994: evidence for the effectiveness of prostate-specific antigen screening

OBJECTIVES

The use of prostate-specific antigen (PSA) to screen for prostate cancer remains controversial. Although it is still too early to measure directly the effects of PSA screening on mortality, we examined changes in the epidemiology of prostate cancer to determine if there is other evidence of the effectiveness of PSA as a screening tool.

METHODS

We examined trends in age at diagnosis, and age-adjusted trends in stage and grade at diagnosis, for 140,936 white and 15,662 African American men diagnosed with prostate cancer from 1973 to 1994 in the National Cancer Institute's Surveillance Epidemiology and End Results data base.

RESULTS

We found a significant downward trend in age at diagnosis, concomitant with a downward shift in stage of disease at diagnosis, starting with the advent of the PSA era in the late 1980s. We noted most cancers detected since the PSA era to be moderately well differentiated (International Classification of Diseases of the World Health Organization grade 2; Gleason score 5, 6, 7) and organ confined. Although findings were similar for both whites and African Americans, African Americans experienced a greater increase in poorly differentiated disease than did whites.

CONCLUSIONS

Changes in the epidemiology of prostate cancer since the advent of the PSA era are consistent with the introduction of an effective screening test. This is evidenced by an increase in detection of significant prostate cancer in individuals who will likely benefit from treatment.

Ultrasound vs CT for the detection of ureteric stones in patients with renal colic

The aim of our study was to compare the accuracy of non-contrast spiral CT with ultrasound (US) for the diagnosis of ureteral calculi in the evaluation of patients with acute flank pain. 62 consecutive patients with flank pain were examined with both CT and US over a period of 9 months. All patients were prospectively defined as either positive or negative for ureterolithiasis, based on follow-up evaluation. 43 of the 62 patients were confirmed as having ureteral calculi based on stone recovery or urological interventions. US showed 93% sensitivity and 95% specificity in the diagnosis of ureterolithiasis; CT showed 91% and 95%, respectively. Pathology unrelated to urinary stone disease was demonstrated in six patients. Although both modalities were excellent for detecting ureteral stones, consideration of cost and radiation lead us to suggest that US be employed first and CT be reserved for when US is unavailable or non-diagnostic.

Does delaying pyeloplasty affect renal function in children with a prenatal diagnosis of pelvi-ureteric junction obstruction?

OBJECTIVE

To evaluate retrospectively children with an antenatal diagnosis of pelvi-ureteric junction (PUJ) obstruction who required pyeloplasty for deteriorating renal function during the follow-up, specifically assessing the recovery of function after surgery.

PATIENTS AND METHODS

Between 1988 and 2000, 44 consecutive patients with a prenatal diagnosis of PUJ obstruction who were initially treated by observation underwent pyeloplasty because their renal function deteriorated during the follow-up. Patients with bilateral disease, a single kidney or vesico-ureteric reflux were excluded from the study. The mean (sd) age of the patients was 13.3 (4.5) months and their mean (range) initial renal function 39.7 (30.4-45)%. In all patients the diagnostic criteria and indications for surgery were identical. The main indication for surgery was deteriorating renal function of >5%, confirmed by renal scintigraphy. Of 44 patients, 35 (77%) had severe dilatation of the renal pelvis by >3 cm. The mean (sd) deterioration in renal function during the follow-up, just before surgery, was 8.2 (2.4)%, and the mean time between the last acceptable renogram and the study showing deterioration was 8.3 (1.3) months; the mean follow-up was 5.1 (1.6) years. The results were assessed statistically using the unpaired nonparametric Mann-Whitney U-test.

RESULTS

An improvement in hydronephrosis was confirmed in all patients, with renal function returning to the initial levels in 36 of 44 (81%) patients 6-12 months after surgery, although in two patients renal function did not improve after surgery. There was no significant difference between the preoperative characteristics and the degree of hydronephrosis, renal function or patient age with the level of renal functional improvement after surgery.

CONCLUSION

In patients with an antenatal diagnosis of PUJ obstruction, expectant management is recommended and spares the children unnecessary surgery. Even if renal function deteriorates, delayed pyeloplasty recovers the initial functional level.

Malnutrition and disability: unexplored opportunities for collaboration

There is increasing international interest in the links between malnutrition and disability: both are major global public health problems, both are key human rights concerns, and both are currently prominent within the global health agenda. In this review, interactions between the two fields are explored and it is argued that strengthening links would lead to important mutual benefits and synergies. At numerous points throughout the life-cycle, malnutrition can cause or contribute to an individual's physical, sensory, intellectual or mental health disability. By working more closely together, these problems can be transformed into opportunities: nutrition services and programmes for children and adults can act as entry points to address and, in some cases, avoid or mitigate disability; disability programmes can improve nutrition for the children and adults they serve. For this to happen, however, political commitment and resources are needed, as are better data.

Relation between growth and the heavy metal concentration in organs of bream Abramis brama L. populating Lake Balaton

The effect of growth and physical condition on the level of heavy metals accumulated in the organs of common bream (Abramis brama L.) populating Lake Balaton was investigated on samples collected in October 1999 and May 2000 from two well-separable sites regarding their trophic state and pollution impact (western and eastern basins). The average metal concentrations in the organs of fish varied in the following ranges: Cd, 0.39-1.98; Cu, 1.73-57.3; Hg, 0.02-0.13; Pb, 0.39-3.15; and Zn, 12.7-159.3 microg/g dry weight. The highest Cd, Cu, Pb and Zn concentrations were detected in the gill and liver of fish, whereas the highest Hg concentrations were measured in the muscle. The maximum metal concentrations in the muscle of bream were on average below the maximum permissible levels for human consumption. Significant positive correlation was found among the heavy metal load of bream and their instantaneous growth rate; hardly any connection was observed related to the physical condition of samples. The relatively low metal concentrations of the ambient water and their poor correlation with the heavy metal load of bream, indicates that for the mature stages of this fish species the metal uptake from food is predominant, and thus the heavy metal load of fish reflect more the pollution state of the sediment and its biota, rather than that of the ambient water.

1-Stage feminizing genitoplasty: 8 years of experience with 49 cases

PURPOSE

We retrospectively evaluated the results of a modified technique for 1-stage feminizing genitoplasty in children with congenital adrenal hyperplasia (CAH) and other rare intersex conditions.

MATERIALS AND METHODS

Between 1991 and 1998, 47 infants and 2 adolescents underwent 1-stage feminizing genitoplasty at our hospital. Of the patients 44 had CAH, 2 had the partial androgen insensitivity syndrome and 3 were true hermaphrodites. In 3 patients we used the Passerini-Glazel technique, while in 46 our technique of feminizing genitoplasty was used, which consists of maximal mobilization of the urogenital sinus en bloc including the vagina and urethra via the perineal approach. Two lateral plates built from dorsal split phallic and preputial skin together with the dorsal split urogenital sinus are used to construct the vaginal introitus and labia minora, and the scrotal folds are used to construct the labia majora. Reduction clitoroplasty is done according to the technique of Kogan et al. Mean age plus or minus standard deviation was 0.9 +/- 0.3 years of the patients with CAH and 13 +/- 2.3 of the remainder. Preoperative information, including status of the internal genitalia, anatomical length of the vagina site of communication between the vagina and urogenital sinus, in relation to the pelvic floor, was obtained by transabdominal pelvic ultrasound.

RESULTS

Operating time ranged between 120 and 180 minutes, average hospitalization period was 4 to 5 days and mean followup was 4.7 +/- 2.6 years. Preoperative ultrasound provided the correct data regarding the vaginal and internal genitalia anatomy in all cases, and the exact communication site between the vagina and urogenital sinus was demonstrated in 93%. Complications consisted of intraoperative rectal injury in 1 case and mild wound infection of the buttocks area in 3. In 1 case total clitoris loss was observed. All patients who underwent modified genitoplasty have had successful cosmetic and early functional results. Two patients presented with repeat clitoromegalia due to inadequate adrenal suppression.

CONCLUSIONS

Our adapted technique of 1-stage feminizing genitoplasty provides good cosmetic and functional results. The functional results of this operation should be reevaluated after puberty and in adulthood.

Patterns of protein kinase C isoenzyme expression in transitional cell carcinoma of bladder. Relation to degree of malignancy

We determined the pattern of protein kinase C (PKC) isoform expression in human cell lines by Western blotting and immunofluorescent staining techniques. In addition, we examined PKC isoform expression in tissue samples of transitional cell carcinoma (TCC) of the bladder. PKC delta, PKC beta II, and PKC eta were found primarily in the RT4 cell line (low-grade tumor), and PKC zeta was expressed most strongly in the SUP cell line (invasive tumor). In tissue samples of urinary bladder cancer, PKC isoenzymes were expressed differentially as a function of tumor stage and grade; expression of PKC beta II and PKC delta was high in normal tissue and in low-grade tumors and decreased with increasing stage and grade of TCC. The opposite pattern was seen with PKC zeta. The differences in expression of specific isoenzymes as related to levels of malignancy of the cell lines and tissue samples suggest that the PKC family has an important role in normal and neoplastic urothelium.

Diverticulitis of the cecum and ascending colon

Twelve cases of acute solitary diverticulitis of the cecum or ascending colon are reviewed. This is frequently indistinguishable from acute appendicitis preoperatively and is often mistaken for carcinoma at laparotomy. There are subtle clinical features that may help to suggest the diagnosis both before and during surgery. If diagnosed preoperatively, it can be treated effectively with broad spectrum antibiotics without surgical intervention. When diagnosed intraoperatively, hemicolectomy can often be avoided. Appendectomy should be done if resection is not performed.

Detailed mathematical description of the geometry of airway bifurcations

Health effects related to the deposition of inhaled aerosol particles in the respiratory system strongly depend on the local deposition patterns. These patterns are highly sensitive to the shape of the airway geometry. The current study presents an exact mathematical description of a morphologically realistic airway bifurcation by further developing an earlier study of the published literature. In addition, numerical methods are elaborated to solve some important tasks, which are necessary for the development of computational fluid dynamics (CFD) techniques in the area of aerosol deposition calculations in the airways. Finally, single and multiple airway geometries and computational grids are generated and analysed.

Septic complications of hemorrhoidal banding

Rubber band ligation is an efficacious and cost-effective alternative to conventional hemorrhoidectomy for symptomatic internal hemorrhoids. Even though the well-recognized complications of bleeding and thrombosis occur infrequently, far more serious septic complications have only recently been described, as evidenced in five of our patients: four cases were serious enough to necessitate surgical intervention, and one patient died. Pain followed by urinary dysfunction with or without toxic symptoms should alert the physician to the probability of localized perianal or systemic sepsis. Acute awareness of these rare but potentially life-threatening complications and immediate aggressive treatment is mandatory if death is to be prevented. Rubber band ligation of internal hemorrhoids need not be abandoned; however, the indications should be clear, the technique mastered, and a close patient follow-up maintained.

Ammonium exchange in leakage waters of waste dumps using natural zeolite from the Krapina region, Croatia

The paper presents the results of investigating the treatment of leakage waters from waste dumps using activated carbon and natural zeolite clinoptilolite, known as a very selective and efficient cation exchanger for ammonium ions. The results are presented of chemical and physical analyses of leakage waters characterized by a high content of ammonium (820 mg L(-1)) and organic pollutants (1033 mg L(-1) C). Physical and chemical characteristics of zeolite and the exchange of ammonium ions in model and real solutions were determined in laboratory trials. Treatment of leakage water with 0.04-2.5% (w/w) activated carbon (Norit 0.8 Supra) led to a reduction of total organic carbon in leakage water from 1033 to 510 mg L(-1). Pretreatment of leakage water with activated carbon did not improve the exchange of ammonium ions on zeolite. Without pretreatment of leakage water, the exchange of ammonium ions amounted to 4.2 mg NH4+/g zeolite. Addition of activated carbon, regardless of its mass, increased the exchange of ammonium ions to only 5.7 mg NH4+/g zeolite. In the model solution of an equal concentration of ammonium as the real solution, 17.70 mg NH4+/g zeolite was exchanged. Organic pollutants that were not eliminated by activated carbon (most probably components of natural origin) adsorbed to zeolite and prevented the exchange of NH4+ ions, which was also reduced due to the presence of K+ and Ca2+ ions.

CD3+CD56+ NK T cells are significantly decreased in the peripheral blood of patients with psoriasis

Psoriasis is a chronic, inflammatory, hyperproliferative skin disease, in which autoimmunity plays a great role. Natural killer T cells (NK T cells), are suggested to be involved in the pathogenesis of different autoimmune diseases. To examine the involvement of CD3+CD56+ NK T cells in the pathogenesis of psoriasis, we investigated the lymphocyte subpopulations obtained from blood samples of psoriatic patients before and after treatment, and of healthy controls, using two-colour flow cytometry. We found no significant differences between total T cells, total B cells, T helper cells, T cytotoxic cells and NK cells in patients with psoriasis before and after treatment and in controls. Increased percentage of memory T cells and decreased percentage of naive T cells was detected in psoriatic patients compared to controls, but these changes were not statistically significant. The CD3+CD56+ cells of psoriatic patients were significantly decreased relative to controls. The percentage of CD3+CD56+ cells increased after different antipsoriatic therapies, but remained significantly lower than those found in controls. CD3+CD56+ cells of healthy controls were capable of rapid activation, while in psoriatic patients activated NK T cells were almost absent. The decrease in the number of CD3+CD56+ cells may represent an intrinsic characteristic feature of patients with psoriasis, which is supported by the fact that after treatment NK T cells do not reach the values found in controls. In conclusion our results suggest that CD3+CD56+ NK T cells could be actively involved in the development of Th1 mediated autoimmune diseases.

Psoriasis and alcohol: is cutaneous ethanol one of the missing links?

Many exogenous factors including excessive alcohol consumption have been associated with psoriasis, but the underlying mechanisms still remain elusive. Drinking worsens therapeutic compliance, and decreases the efficacy and increases the toxicity of systemic antipsoriatic treatments. Excess alcohol intake results in compromised immunity and increased risk of infections, but alcohol can induce proinflammatory cytokine production in various cell types and can increase mitogen-derived lymphocyte proliferation and lymphocyte activation. As we have previously reported, alcohol and one of its metabolites, acetone, induce keratinocyte proliferation and increase the mRNA levels of genes characteristic for proliferating keratinocytes, such as alpha5 integrin, cyclin D1 and keratinocyte growth factor receptor. Recently the correlation between blood and skin ethanol levels in humans was determined by a transdermal alcohol monitoring device, against the 'gold standard' breath alcohol readings. Based on transdermal alcohol measurements it can be concluded that cutaneous alcohol concentrations can reach levels that induce proinflammatory cytokine production and lymphocyte and keratinocyte proliferation in vitro. It is expected that the development of methodologies measuring transdermal ethanol will provide additional tools to evaluate how alcohol influences skin physiology and different dermatological conditions including psoriasis. Our review focuses on the possible link between alcohol misuse and psoriasis, particularly on the possible role of cutaneous ethanol in precipitating the disease.

Interferon-α in the generation of monocyte-derived dendritic cells: recent advances and implications for dermatology

Dendritic cells (DCs) have a critical role in antiviral responses, in autoimmune disease pathogenesis and in initiating and maintaining inflammatory skin disorders, and are candidates for cell-based immunotherapeutic approaches for tumours. Recent studies have shown the important role of type I interferons (IFNs) in DC differentiation and activation. In the presence of IFN-α and granulocyte/macrophage colony-stimulating factor monocytes differentiate into DCs referred to as IFN-DCs. In vitro generated IFN-DCs show a partially mature phenotype, are effective in taking up antigens, share features of myeloid DCs, plasmacytoid DCs and natural killer cells, exhibit an enhanced chemotactic response and are capable of migrating to the lymph nodes. IFN-DCs produce several chemokines and cytokines, including T-helper 1 (Th1) mediators belonging to the interleukin-12 family. IFN-DCs stimulate T- and B-cell responses and the production of IFN-γ in mixed lymphocyte reactions and have a capacity to produce IFN-γ themselves. IFN-DCs express several toll-like receptor (TLR) subtypes and TLR ligand stimulation improves their costimulatory molecule expression, increases their Th1 cytokine production and enhances their capacity to stimulate naive T-cell proliferation. Here we review the interaction of IFN-α and monocytes and the role of IFN-DCs in infections, in autoimmunity, in inflammation and in cancer immunotherapy focusing on dermatological conditions.

Neonicotinoid insecticides inhibit cholinergic neurotransmission in a molluscan (Lymnaea stagnalis) nervous system

Neonicotinoids are highly potent and selective systemic insecticides, but their widespread use also has a growing impact on non-target animals and contaminates the environment, including surface waters. We tested the neonicotinoid insecticides commercially available in Hungary (acetamiprid, Mospilan; imidacloprid, Kohinor; thiamethoxam, Actara; clothianidin, Apacs; thiacloprid, Calypso) on cholinergic synapses that exist between the VD4 and RPeD1 neurons in the central nervous system of the pond snail Lymnaea stagnalis. In the concentration range used (0.01-1 mg/ml), neither chemical acted as an acetylcholine (ACh) agonist; instead, both displayed antagonist activity, inhibiting the cholinergic excitatory components of the VD4-RPeD1 connection. Thiacloprid (0.01 mg/ml) blocked almost 90% of excitatory postsynaptic potentials (EPSPs), while the less effective thiamethoxam (0.1 mg/ml) reduced the synaptic responses by about 15%. The ACh-evoked membrane responses of the RPeD1 neuron were similarly inhibited by the neonicotinoids, confirming that the same ACh receptor (AChR) target was involved. We conclude that neonicotinoids act on nicotinergic acetylcholine receptors (nAChRs) in the snail CNS. This has been established previously in the insect CNS; however, our data indicate differences in the background mechanism or the nAChR binding site in the snail. Here, we provide the first results concerning neonicotinoid-related toxic effects on the neuronal connections in the molluscan nervous system. Aquatic animals, including molluscs, are at direct risk while facing contaminated surface waters, and snails may provide a suitable model for further studies of the behavioral/neuronal consequences of intoxication by neonicotinoids.

TER94, a Drosophila homolog of the membrane fusion protein CDC48/p97, is accumulated in nonproliferating cells: in the reproductive organs and in the brain of the imago

We have cloned a Drosophila homolog of the membrane fusion protein CDC48/p97. The open reading frame of the Drosophila homolog encodes an 801 amino acid long protein (TER94), which shows high similarity to the known CDC48/p97 sequences. The chromosomal position of TER94 is 46 C/D. TER94 is expressed in embryo, in pupae and in imago, but is suppressed in larva. In the imago, the immunoreactivity was exclusively present in the head and in the gonads of both sexes. In the head the most striking staining was observed in the entire neuropil of the mushroom body and in the antennal glomeruli. Besides TER94, sex-specific forms were also detected in the gonads of the imago: p47 in the ovaries and p98 in the testis. TER94/p47 staining was observed in the nurse cells and often in the oöcytes, while TER94/p98 staining was present in the sperm bundles. On the basis of its distribution we suggest that TER94 functions in the protein transport utilizing endoplasmic reticulum and Golgi derived vesicles.

Endoscopic correction of vesicoureteral reflux: our experience with 115 ureters

Endoscopic subureteral injection of polytetrafluoroethylene was performed in 115 ureters to correct vesicoureteral reflux. We treated primary reflux in 84 single ureters, 16 duplex ureters and 4 megaureters (grade V), and secondary reflux in 11 ureters associated with neurogenic bladder, uncapped ureteroceles and failed ureteroneocystostomy. Followup evaluation consisted of a voiding cystourethrogram, which was done in the operating room immediately after the endoscopic procedure, ultrasound 1 month postoperatively, and a diethylenetriaminepentaacetic acid renal isotope scan and repeat voiding cystourethrogram 6 months after injection. Grades II to IV primary reflux involving single as well as duplex ureters resolved in 94% and 82%, respectively, of the cases after 1 injection and in 98% and 93% of the cases after 2 or more injections. The severely and chronically dilated ureters did not respond to the treatment.

The nature of the defect in familial male pseudohermaphroditism in Arabs of Gaza

Studies in six Arab individuals from Gaza with familial male pseudohermaphroditism (MPH) due to 17-ketoreductase deficiency revealed several metabolic aberrations associated with the disorder. Plasma LH, FSH, testosterone, and androstenedione concentrations were low in the two prepubertal patients. After hCG administration plasma androstenedione increased markedly. The four postpubertal MPH patients had very high plasma gonadotropin and androstenedione concentrations, the latter increasing further after hCG administration. Plasma testosterone concentrations in all six patients were moderately low or normal for age and increased little after hCG administration. Spermatic venous testosterone concentrations, measured in three adults, were within the normal range in two and low in one, while androstenedione concentrations were markedly elevated (15- to 32-fold) in all three patients. Kinetic analyses of progesterone and androstenedione metabolism were performed in testicular tissue of these patients and compared to the results in two control subjects. While testicular tissue from the two prepubertal patients metabolized progesterone only to androstenedione, and that to a limited extent, the tissue from the four postpubertal patients metabolized progesterone to 16 alpha- and 16 beta-hydroxyprogesterone, 17 alpha-hydroxyprogesterone, androstenedione, and testosterone and metabolized androstenedione to testosterone. The Michaelis constants of these reactions were similar in the tissue from the MPH and the control subjects. The production of 16 alpha- plus 16 beta-hydroxyprogesterone was 5.4- to 10.3-fold greater, and 17-hydroxylase activity was 5.8- to 8.1-fold lower in the testes of the postpubertal MPH patients compared to values in the control subjects. The preference of androstenedione production through the delta 4- or delta 5-pathways was examined in the testes of two adult MPH patients using an equimolar concentration of [14C]progesterone and [3H]pregnenolone as substrates. While the flow of substrates in the control testes was equal or slightly greater through the delta 4-pathway, the delta 5-pathway predominated in the testes of the MPH patients. A large amount of dehydroepiandrosterone accumulated when NAD, the cofactor for 3 beta-hydroxysteroid dehydrogenase-isomerase, was omitted, supporting the contention that androstenedione was produced in the testes of the MPH patients mainly through the delta 5-pathway. Additional support for this suggestion was the finding that the 3H/14C ratio in androstenedione and testosterone produced from both substrates was 8 times higher in the testes from MPH patients than in those from the control subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Interferon-alpha and viral triggers promote functional maturation of human monocyte-derived dendritic cells

BACKGROUND

Type I interferons (IFNs) play an important role in the pathogenesis of many autoimmune disorders including psoriasis. In the presence of IFN-alpha and granulocyte/macrophage colony-stimulating factor (GM-CSF), monocytes differentiate into dendritic cells (DCs) referred to as IFN-DCs. IFN-DCs potentially mimic DC populations involved in psoriasis and express a wide range of Toll-like receptor (TLR) subtypes.

OBJECTIVES

Recently, it was shown that single-stranded RNA (ssRNA) triggers TLR7 and TLR8; therefore we studied ssRNA, as a surrogate for ssRNA viruses and their impact on IFN-DCs.

METHODS

We established culture conditions for IFN-DCs, generated from plastic adherent monocytes using GM-CSF plus IFN-alpha. For DC stimulation ssRNA40, a 20-mer ssRNA oligonucleotide was used. The phenotypic analysis of DC preparations was performed using flow cytometry. The production of various cytokines was analysed by enzyme-linked immunosorbent assay, and real-time quantitative polymerase chain reaction was used to quantify TLR and cytokine gene expression. The ability of IFN-DCs to stimulate allogeneic T-cell proliferation was evaluated in a mixed leucocyte reaction.

RESULTS

We found that IFN-DCs express mRNA for TLR7 and TLR8 and that ssRNA stimulation significantly improves their costimulatory molecule expression, stabilizes their phenotype and enhances their capacity to stimulate naive T-cell proliferation. Unstimulated IFN-DCs did not produce bioactive interleukin (IL)-12 and produced low levels of other proinflammatory cytokines. In contrast, ssRNA stimulation led to a significant production of IL-12p70, IL-1beta, IL-6 and tumour necrosis factor alpha. IFN-DCs contained mRNA for IL-12p35, IL-12p40, IL-23p19, IL-27p28 and IL-27EBI, which was further increased by incubation with ssRNA.

CONCLUSIONS

Our study sheds light on a potential role for IFN-alpha and viral infections in triggering DC populations in psoriasis. These results provide additional data for the better understanding of human autoimmune and antiviral responses and may also have implications for strategies developing cancer immunotherapy.

Obstetric admissions to an intensive therapy unit

Complications of pregnancy may necessitate admission to an Intensive Therapy Unit (ITU). All obstetric patients admitted to ITU were reviewed in order to assess whether these admissions could have been predicted and to determine the place of intensive care compared with high dependency nursing. Case notes of 122 women from a total group of 144 women admitted to an ITU of an inner-city hospital from 1989-1993 were reviewed retrospectively. The majority of women (67%) had no pre-existing medical or obstetric history. The major indications for admission were hypertensive disease of pregnancy (66%) and haemorrhage (19%); 79% followed caesarean section and 40% required ventilatory support. The perinatal mortality rate was 6% and there were three maternal deaths. The need for admission to ITU was unpredictable in two-thirds of the cases. Many of the women evaluated in this review were ineligible for high dependency care and required full ITU facilities, both of which will always be needed to deal with serious complications of pregnancy.

Tandem CAG repeats of the androgen receptor gene and prostate cancer risk in black and white men

The most common malignancy in men worldwide is cancer of the prostate. Androgens play a direct role in normal and malignant growth of prostate cells via the androgen receptor (AR). This study analyzed the polymorphic CAG repeat sequence in exon 1 of the AR gene to determine if the number of repeats might be an indicator of prostate cancer risk or aggressive disease. DNA was extracted from blood samples of 20 black and 20 white men with well-documented prostate cancer and 40 healthy controls (20 blacks and 20 whites). PCR amplification was followed by gel electrophoresis and DNA sequencing. This region normally contains between 9 and 29 repeats. Patients and controls both had minor variations in the number of repeats, which ranged from 13 to 27 with 21 being the most frequent allele. Black controls and patients both had a mean of 20 +/- 3 repeats; in whites the mean was significantly lower in patients than controls (21 +/- 2 versus 23 +/- 2; p = 0.004). Combined black and white patients also had a lower number than the combined group of controls (20 +/- 3 versus 22 +/- 3; p = 0.02). Similarly, black and white patients with aggressive disease had a lower number than patients whose disease was more slowly progressive (19 +/- 2 versus 22 +/- 3; p = 0.02). We conclude that the small differences in the number of CAG repeats in both black and white patients do not appear to be a strong indicator of risk or aggressive disease but that this size polymorphism may be one of many genetic and environmental risk factors involved in prostate cancer.

Decationization and dealumination of clinoptilolite tuff and ammonium exchange on acid-modified tuff

The paper presents results of investigation of exchange of the clinoptilolite tuff cations with hydrogen ions from HCl solution of concentration 0.1 mmol cm(-3) and ammonium ions solutions of concentrations 0.0071 to 2.6 mmol cm(-3). Molal concentrations, x (mmol g(-1)) of cations exchanged in acid solution and in ammonium ions solutions were compared with molal concentrations of cations obtained by determination of the cation-exchange capacity of clinoptilolite tuff. The obtained results show that at ammonium ion concentrations lower than 0.1 mmol cm(-3), with regard to exchange capacity for particular ions, best exchanged are Na+ ions, followed by Mg2+ and Ca2+ ions, while exchange of K+ ions is the poorest (Na+ > Mg2+ > Ca2+ > K+). At ammonium concentrations from 0.2 to 1 mmol cm(-3) the order is Na+ > Ca2+ > Mg2+ > K+. At concentrations higher than 1 mmol cm(-3) the order is Na+ > Ca2+ > K+ > Mg2+. The results are a consequence of the uptake of hydrogen ions by zeolite samples in ammonium ions solutions at concentrations lower than 1 mmol cm(-3) and indicate the importance of Mg2+ (besides Na+ ions) for the exchange between clinoptilolite cations and H+ ions, in contrast to K+ ions, whose participation in the reaction with H+ ions is the lowest. During decationization of the clinoptilolite in acid solution, best exchanged are Na+, Mg2+, and Ca2+ ions, while exchange of K+ ions is the poorest. Due to poor exchange of K+ and H+ ions and good exchange of Na+, Mg2+, and Ca2+ ions, it is to be assumed that preservation of stability of the clinoptilolite structure is caused by K+ ions present in the channel C. Clinoptilolite is dissolved in the clinoptilolite A and B channels where Na+, Mg2+, and Ca2+ ions are present. On the acid-modified clinoptilolite samples, exchange of ammonium ions is poorer than on natural zeolite. The longer the contact time of the zeolite and acid solution, the worse ammonium ions exchange. It can be assumed that H+ ions exchanged with zeolite cations are consumed for solution of aluminum in the clinoptilolite structure; therefore the concentration of H+ ions as exchangeable cations decreases. In the ammonium ion solution at a concentration of 0.0065 mmol cm(-3), from the acid-modified zeolite samples, Al3+ ions are exchanged best, followed by Na+, Mg2+, Ca2+, and K+ ions. Further to the results, it is to be assumed that exchangeable Al3+ ions available from clinoptilolite dissolution are best exchanged with H+ ions in acid solution.

Dithranol upregulates IL-10 receptors on the cultured human keratinocyte cell line HaCaT

OBJECTIVE

Dithranol is highly effective in the treatment of psoriasis, however its mode of action is still not well known. Since interleukin-8 and interleukin-10 are involved in the pathogenesis of psoriasis, the aim of our study was to investigate the effect of dithranol on interleukin-8, interleukin-10 mRNA production and interleukin-10 receptor expression of the HaCaT keratinocyte cell line which is commonly used in experiments examining the effects of therapeutic drugs on keratinocytes.

MATERIALS AND METHODS

Cultured HaCaT cells were treated with 0.1-0.5 microg/ml dithranol for 30 minutes. After 2 and 4 h total cellular RNA isolated from HaCaT cells was reverse transcribed (RT) to cDNA which was subjected to polymerase chain reaction (PCR) with specific primer pairs for interleukin-8, interleukin-10 and interleukin-10 receptor. For immunohistochemistry cultured HaCaT cells were stained with a monoclonal antibody against the human interleukin-10 receptor.

RESULTS

Our results showed that dithranol treatment did not change the highly elevated level of interleukin-8 mRNA of HaCaT cells. Interleukin-10 mRNA signal with RT-PCR could not be detected in HaCaT cells. Depending on the concentration dithranol increased the mRNA production of interleukin-10 receptors in HaCaT cells. This dithranol induced dose dependent upregulation of IL-10 receptors in HaCaT cells was also observed on the protein level using immunohistochemistry.

CONCLUSIONS

Since the interleukin-10 receptor expression of keratinocytes in psoriatic lesional skin is downregulated, the dithranol induced upregulation of the receptor in our model system might help to reveal the therapeutic action of the drug.