Association of C4d deposition with clinical outcomes in IgA nephropathy

BACKGROUND AND OBJECTIVES

Several studies have suggested that activation of the complement system is a contributing pathogenic mechanism in IgA nephropathy (IgAN). C4d staining is an inexpensive and easy-to-perform method for the analysis of renal biopsies. This study aimed to assess the clinical and prognostic implications of C4d staining in IgAN.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This retrospective cohort study included 283 patients with IgAN in 11 hospitals in Spain who underwent a renal biopsy between 1979 and 2010. The primary predictor was mesangial C4d staining. Secondary predictors included demographic, clinical, and laboratory characteristics, and Oxford pathologic classification criteria. The primary end point was the cumulative percentage of patients who developed ESRD, defined as onset of chronic dialysis or renal transplantation. C4d was analyzed by immunohistochemical staining using a polyclonal antibody. Kaplan-Meier and Cox proportional hazards analyses were performed to evaluate the effect of C4d staining on renal survival.

RESULTS

There were 109 patients (38.5%) and 174 patients (61.5%) who were classified as C4d positive and C4d negative, respectively. Renal survival at 20 years was 28% in C4d-positive patients versus 85% in C4d-negative patients (P<0.001). Independent risk factors associated with ESRD were as follows: proteinuria (hazard ratio [HR] per every 1 g/d increase. 1.16; 95% confidence interval [95% CI], 1.03 to 1.31; P=0.01), eGFR (HR per every 1 ml/min per 1.73 m(2) increase, 0.96; 95% CI, 0.94 to 0.97; P<0.001), T2 Oxford classification (tubular atrophy/interstitial fibrosis, >50%; HR, 4.42; 95% CI, 1.40 to 13.88; P=0.01), and C4d-positive staining (HR, 2.45; 95% CI, 1.30 to 4.64; P=0.01).

CONCLUSIONS

C4d-positive staining is an independent risk factor for the development of ESRD in IgAN. This finding is consistent with the possibility that complement activation is involved in the pathogenesis of this disease.

Analytical tools for speciation in the field of toxicology

The knowledge of the speciation of elements at trace and ultra-trace level, in biological and environmental media is essential to acquire a better understanding of the mechanisms of toxicity, transport and accumulation in which they are involved. Determining the speciation of an element in a given medium is challenging and requires the knowledge of different methodological approaches: the calculation approach and the experimental approach through the use of dedicated analytical and spectroscopic tools. In this framework, this mini-review reports the approaches to investigate the speciation of elements in biological and environmental media as well as the experimental techniques of speciation analysis, illustrated by recent examples. The main analytical and spectroscopic techniques to obtain structural, molecular, elemental and isotopic information are described. A brief overview of separation techniques coupled with spectrometric techniques is given. Imaging and micro-localisation techniques, which aim at determining the in situ spatial distribution of elements and molecules in various solid samples, are also presented. The last part deals with the development of micro-analytical systems, since they open crucial perspectives to speciation analysis for low sample amounts and analysis on field.

Dosimetry of a cone beam CT device for oral and maxillofacial radiology using Monte Carlo techniques and ICRP adult reference computational phantoms

OBJECTIVES

The aim of this study was to calculate organ and effective doses for a range of available protocols in a particular cone beam CT (CBCT) scanner dedicated to dentistry and to derive effective dose conversion factors.

METHODS

Monte Carlo simulations were used to calculate organ and effective doses using the International Commission on Radiological Protection voxel adult male and female reference phantoms (AM and AF) in an i-CAT CBCT. Nine different fields of view (FOVs) were simulated considering full- and half-rotation modes, and also a high-resolution acquisition for a particular protocol. Dose-area product (DAP) was measured.

RESULTS

Dose to organs varied for the different FOVs, usually being higher in the AF phantom. For 360°, effective doses were in the range of 25-66 μSv, and 46 μSv for full head. Higher contributions to the effective dose corresponded to the remainder (31%; 27-36 range), salivary glands (23%; 20-29%), thyroid (13%; 8-17%), red bone marrow (10%; 9-11%) and oesophagus (7%; 4-10%). The high-resolution protocol doubled the standard resolution doses. DAP values were between 181 mGy cm(2) and 556 mGy cm(2) for 360°. For 180° protocols, dose to organs, effective dose and DAP were approximately 40% lower. A conversion factor (DAP to effective dose) of 0.130 ± 0.006 μSv mGy(-1) cm(-2) was derived for all the protocols, excluding full head. A wide variation in dose to eye lens and thyroid was found when shifting the FOV in the AF phantom.

CONCLUSIONS

Organ and effective doses varied according to field size, acquisition angle and positioning of the beam relative to radiosensitive organs. Good positive correlation between calculated effective dose and measured DAP was found.

Recurrent membranoproliferative glomerulonephritis after second renal graft treated with plasmapheresis and rituximab

We present a case of a 45-year-old man who suffered from idiopatic membranoproliferative glomerulonephritis (MPGN) in the native kidney that relapsed after his first and second renal grafts. The patient was diagnosed in 1990 with lobular MPGN type I, receiving his first renal graft in 1996. In 2001, a biopsy showed recurrence of MPGN type I (rMPGN). He underwent a second renal graft in 2008. In January 2010, he experienced increased proteinuria and creatinine. Upon electron microscopy of a renal graft biopsy we diagnosed a new rMPGN. At the time of the biopsy, complement levels were normal, although C3 and C4 decreased further. We administered 12 plasmapheresis (PP) sessions and four doses of rituximab. Due to persistent renal impairment, we performed a new biopsy 3 months later, showing less severity of the acute lessions. He received a new cycle of treatment (PP+rituximab). One year later, his renal function was stable with a creatinine ranging between 2 and 2.5 mg/dL and a protein/creatinine ratio less than 1 mg/mg. We concluded that the treatment stopped the disease progression.

Impact of recurrent glomerulonephritis on renal graft survival

BACKGROUND

Glomerular disease causes graft loss in the intermediate and long term, especially recurrent primary renal disease, negatively impacting graft survival. Thus, it must be considered a differential diagnosis in the evaluation of chronic graft dysfunction.

METHODS

The objectives of our study were to compare the impacts of primary glomerular disease on graft survival and association with interstitial fibrosis/tubular atrophy (IFTA) or transplant glomerulopathy. We examined the influence of the relapse of glomerulonephritis (GN) on renal graft survival in a retrospective study of 1057 patients undergoing renal transplantations between March 1981 and October 2009. Among this group, 128 patients were diagnosed with pretransplant GN by renal biopsy. We examined graft survival on recurrence compared with IFTA and transplant glomerulopathy using Kaplan-Meier analysis.

RESULTS

We analyzed a cohort of 128 patients who were diagnosed with pretransplant GN by renal biopsy, including 28.9% (37) of whom were males. The mean age was 42.04 ± 13.82 years. The most frequent type was immunoglobulin A GN (IgAGN; 31.3%), followed by membranoproliferative GN (MPGN; 28.9%), rapidly progressive GN (RPGN; 16.4%), focal-segmental GN (FSGN; 13.3%), membranous GN (9.4%), and minimal change GN; (0.8%). Among the 16 cases (12.5%) of GN recurrence; MPGN was associated most frequently (n = 10, 28.9%), followed by FSGN (n = 4, 23.5%), RPGN (n = 1, 4.8%), and IgAGN (n = 1, 2.5%). We noted that 11.8% of subjects to be positive for hepatitis C virus; while 3.9% were hepatitis B virus(HBV)-positive. We observed no differences in hepatic serology between patients who experienced recurrence (HBV 6.3% vs hepatitis C virus [HCV] 18.8%) compared with IFTA (HBV 3.1% vs HCV 9.4%). Fifty-one patients (39.8%) were biopsied after transplantation due to impaired renal function: there were recurrences of GN in 12.5% (n = 16), IFTA in 25% (n = 32), and transplant glomerulopathy in 2.3% (n = 3) cases. The average graft survival in our cohort was 8.36 ± 0.59 years. The median patient survival among those who experienced a recurrence was 8.36 ± 1.79 years; 7.19 ± 1.01 years in IFTA patients; and 3.31 ± 0.91 years in patients with transplant glomerulopathy (log-rank P = .06). Upon multivariate analysis, recurrence of GN was not an independent predictor of renal loss.

CONCLUSIONS

MPGN was the type of GN that recurred most frequently followed by FSGN. No differences in graft survival were noted between long-term recurrence of GN and other causes of chronic graft dysfunction. The recurrence of primary disease did not worsen the renal graft prognosis versus other causes of chronic graft dysfunction.

Neoadjuvant intraperitoneal chemotherapy with paclitaxel for the radical surgical treatment of peritoneal carcinomatosis in ovarian cancer: a prospective pilot study

PURPOSE

The admitted benefits of intraperitoneal chemotherapy during postoperative administration for the treatment of peritoneal carcinomatosis from ovarian origin are limited by their associated morbidity and restricted diffusion by the presence of multiple intra-abdominal adherences. The purpose of the study was to evaluate the security, effectiveness, and cytoreduction optimization of intraperitoneal paclitaxel administration previously to radical surgery/peritonectomy/HIPEC (hyperthermic intraoperative intraperitoneal chemotherapy) either in monotherapy or combined with intravenous carboplatin.

METHODS

Prospective pilot study of 10 patients with ovarian peritoneal carcinomatosis in stage IIIc-FIGO without previous treatment. After staging of the diseases by laparoscopy, five patients received paclitaxel by weekly intraperitoneal administration (60 mg/m(2), 10 cycles), and other five patients additionally received intravenous carboplatin every 21 days (AUC 6, 4 cycles). Subsequently radical surgery/peritonectomy with HIPEC was performed.

RESULTS

The presence of moderate abdominal pain was the most common (70%) side effect associated with neoadjuvant paclitaxel intraperitoneal administration. The intravenous carboplatin administration was not associated with significant increase in adverse effects. It boosted intraperitoneal paclitaxel-associated antitumoral activity with a high average decrease in Index Cancer Peritoneal (21.2 vs. 14.4, P = 0.066) and CA 125(1,053 vs. 346, P = 0.043). All the patients who received combined neoadjuvant chemotherapy obtained R0 cytoreduction. Five-year overall survival was 62%.

CONCLUSIONS

The intraperitoneal paclitaxel weekly administration combined with intravenous carboplatin administration prior to radical surgery/peritonectomy with HIPEC is a safe and effective option in the treatment of ovarian peritoneal carcinomatosis. This study shows the possibility to investigate other forms of intraperitoneal chemotherapy and their combinations thoroughly.

Autonomic and metabolic effects of OSA in childhood obesity

This study investigates the effects of exposure to intermittent hypoxia on cardiovascular autonomic control and metabolic function in obese children with obstructive sleep apnea (OSA). Each subject underwent: (1) a polysomnography; (2) morning fasting blood samples and a subsequent FSIVGTT; (3) noninvasive measurement of respiration, arterial blood pressure, and heart rate during supine and standing postures. Assessment of adiposity was performed using a DEXA scan. From these measurements, we deduced the pertinent sleep parameters, Bergman minimal model parameters and the parameters characterizing a minimal model of cardiovascular variability. Results suggest that intermittent hypoxia in OSA contributes independently to insulin resistance and autonomic dysfunction in overweight children.

Darbepoetin-α treatment enhances glomerular regenerative process in the Thy-1 glomerulonephritis model

Recent studies have demonstrated that erythropoietin (EPO) and its analogs induce cytoprotective effects on many nonerythroid cells. In this study, we examined whether darbepoetin-α might prevent glomerular lesions in the Thy-1.1 model of glomerulonephritis (Thy-1-GN). GN was induced in Wistar rats by a single injection of monoclonal anti-Thy-1.1 antibody. Rats were killed at 24 h, 72 h, 7 days, 10 days, or 15 days after antibody injection. Kidneys were removed for histological analysis, and proteinuria was measured. Because at day 7 the maximal degree of renal damage and proteinuria was found, the effect of darbepoetin-α was tested at day 7 and two different protocols of administration were used; After anti-Thy-1.1 injection, rats received two doses of darbepoetin-α or vehicle at days 0 and 4 or at days 4 and 6. At day 7, proteinuria, plasma creatinine concentration, and renal morphology analysis were performed. Also, α-actin, desmin, caspase-3, and Ki67 protein expression were evaluated by immunohistochemistry. Our results showed that in both protocols of administration, darbepoetin-α treatment decreased proteinuria in Thy-1-GN rats and this effect correlated with the improvement in renal morphology. Glomerular lesions, α-actin, and caspase-3 protein expression, observed in most glomeruli of Thy-1-GN rats, were significantly reduced in darbepoetin-α-treated rats, while cell proliferation was significantly enhanced. The results indicate that darbepoetin-α treatment promotes glomerular recovery.

Continuous versus interrupted sutures for repair of episiotomy or second-degree perineal tears: a randomised controlled trial

OBJECTIVE

To evaluate the repair techniques of continuous and interrupted methods for episiotomy or perineal tears.

DESIGN

A randomised controlled trial.

SETTING

The Hospital Universitario Principe de Asturias, a state hospital belonging to the community of Madrid.

SAMPLE

Four hundred forty-five women who had undergone vaginal deliveries with episiotomies or second-grade tearing of the perineum between September 2005 and July 2007.

METHODS

One group was repaired with continuous, nonlocking sutures involving the vagina, perineum, and subcutaneous tissues. The other group had continuous, locking sutures of the vagina, interrupted sutures in the perineal muscles, and interrupted transcutaneous sutures. The threads used for stitching were identical in both groups.

MAIN OUTCOME MEASURES

The participants were questioned regarding the sensation of pain and the use of painkillers on the second and the tenth days, and 3 months postpartum.

RESULTS

When comparing the group with continuous suture to the group with interrupted sutures, the differences included less repair time (1 minute; P= 0.017) and less suture material used (relative risk [RR], 3.2, 95% CI: 2.6-4.0). The comparison of pain on the second and tenth days, and 3 months postpartum were not statistically different between the two techniques (RR, 1.08, 95% CI: 0.74-1.57; RR, 0.96, 95% CI: 0.59-1.55; and RR, 0.68, 95% CI: 0.19-2.46, respectively).

CONCLUSIONS

Although we did not demonstrate that one technique was better than the other in the incidence of pain in the short or long term, we showed that episiotomy and perineal tear repairs with continuous suturing were quicker and used less suture material without an increase in complication than interrupted suturing.

[Cardiovascular risk in subjects with high probability of metabolic syndrome and insulin resistance. DESIRE study]

INTRODUCTION AND OBJECTIVES

The metabolic syndrome is an association of closely related alterations. The main objective of this study is to know the frequency of the metabolic syndrome and insulin resistance, and their role as cardiovascular risk indicators in an adult population assigned to Primary Care centers in Spain.

METHODS

Subjects > or = 45 years with basal glycemia > or = 90 mg/dl and abdominal circumference > or = 94 cm (men) or > or = 80 cm (women). ATP III modified-criteria were used for the metabolic syndrome and HOMA index > 3.29 was used for insulin resistance. Cardiovascular risk was estimated by the Framingham and SCORE models.

RESULTS

A total of 2,341 subjects (62 +/- 10 years; 44.6% males) were included. Frequency of metabolic syndrome and insulin resistance was 54.6% (52.5; 56.8) and 56.6% (54.5; 58.7) respectively. Metabolic syndrome was associated to a higher cardiovascular risk score with both Framingham (16 [15; 16] vs 11 [11; 12] p < 0.0001) and SCORE (2.7 [2.4; 3] vs 2.4 [2.1; 2.8]; p = 0.006) models. The results were similar for the presence of insulin resistance.

CONCLUSIONS

Metabolic syndrome and insulin resistance are cardiovascular risk predictors. Early identification of metabolic syndrome by the use of simple clinical measures (basal glycemia and waist circumference) would make the intervention on the different disorders of metabolic syndrome possible.

Mesangial C4d deposition: a new prognostic factor in IgA nephropathy

BACKGROUND

It has been shown that patients with IgA nephropathy can be divided into two groups on the basis of the pattern of complement activation. Activation of the lectin pathway of complement is associated with more severe renal disease. Glomerular deposition of C4d is a marker of activation of the lectin pathway of complement. The aim of our study was to determine whether C4d staining at the time of the renal biopsy could identify patients with a different long-term prognosis in IgA nephropathy.

METHODS

This retrospective cohort study included all patients with IgA nephropathy who underwent renal biopsy at our centre from January 1992 to December 2006. We evaluated baseline age, sex, presence of macroscopic haematuria, hypertension, serum creatinine and glomerular filtration rate (GFR), urine protein, mesangial C4d staining, glomerulosclerosis, interstitial fibrosis and extracapillary proliferation. Kaplan-Meier survival and Cox proportional hazards analyses were performed, with end-stage renal disease (ESRD) being defined as onset of dialysis or transplantation.

RESULTS

Nineteen patients (32.2%) were C4d positive and 40 patients (67.8%) C4d negative. Age, hypertension, absence of macroscopic haematuria, serum creatinine levels, GFR, glomerular sclerosis, interstitial fibrosis and C4d-positive staining were all univariately associated with evolution to ESRD. Renal survival at 10 years was 43.9% in C4d-positive patients versus 90.9% in C4d-negative patients (log-rank, P = 0.0005).

CONCLUSION

Negative mesangial C4d staining in glomeruli in patients with IgA nephropathy helps to identify patients with a good long-term prognostic for whom aggressive treatments are not justified.

Quantitative micro-analysis of metal ions in subcellular compartments of cultured dopaminergic cells by combination of three ion beam techniques

Quantification of the trace element content of subcellular compartments is a challenging task because of the lack of analytical quantitative techniques with adequate spatial resolution and sensitivity. Ion beam micro-analysis, using MeV protons or alpha particles, offers a unique combination of analytical methods that can be used with micrometric resolution for the determination of chemical element distributions. This work illustrates how the association of three ion beam analytical methods, PIXE (particle induced X-ray emission), BS (backscattering spectrometry), and STIM (scanning transmission ion spectrometry), allows quantitative determination of the trace element content of single cells. PIXE is used for trace element detection while BS enables beam-current normalization, and STIM local mass determination. These methods were applied to freeze-dried cells, following a specific cryogenic protocol for sample preparation which preserves biological structures and chemical distributions in the cells. We investigated how iron accumulates into dopaminergic cells cultured in vitro. We found that the iron content increases in dopaminergic cells exposed to an excess iron, with marked accumulation within distal ends, suggesting interaction between iron and dopamine within neurotransmitter vesicles. Increased iron content of dopaminergic neurons is suspected to promote neurodegeneration in Parkinson's disease.

Health-related quality of life in patients with osteoarthritis after total knee replacement: factors influencing outcomes at 36 months of follow-up

OBJECTIVES

(1) To evaluate health-related quality of life (HRQL) in patients with severe osteoarthritis (OA) undergoing total knee replacement (TKR) and (2) to identify the influence of sociodemographic, clinical, intra-operative and postoperative variables on HRQL at 36 months after TKR.

DESIGN

Prospective study with a 36-month follow-up. Preoperative interviews were carried out with 90 in-patients. The disease-specific Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire was used to measure the health status. Sociodemographic, clinical, intra-operative degree of difficulty, in-patient and postoperative data were collected. Associations were analyzed using linear regression models.

RESULTS

Of the 90 potentially eligible patients, 67 (54 females, mean age 74.83, standard deviation [SD] 5.57) completed follow-up assessment. There were significant differences between preoperative and postoperative WOMAC pain, stiffness and function scores (P<0.001, P=0.005 and P<0.001, respectively). Variables retained in each of the models explained between 15% and 23% (R(2) adjusted) of the variability of each WOMAC dimension. Higher preoperative WOMAC scores were associated with greater postoperative improvement (P<0.001). Chronic musculoskeletal pain unrelated to knee OA was associated with higher WOMAC pain, stiffness and function dimension scores (P=0.004, P=0.029 and P=0.005, respectively). Severe (Class III) obesity (body mass index [BMI] 35-39.9) was associated with more pain (P=0.049).

CONCLUSIONS

In patients with severe OA, HRQL significantly improved at 36 months after TKR, especially in the pain dimension. Lower preoperative WOMAC scores, chronic pain unrelated to knee OA, and severe obesity negatively influenced postoperative WOMAC scores. This disease-specific questionnaire may help to identify patients at increased risk of negative outcomes after surgery.

[Alterations in bone mineral metabolism in patients with calcium kidney stone disease and polymorphism of vitamin D receptor. Preliminary results]

Bone health, within calcium kidney stone disease is a matter of controversy. On the other hand, some genetic studies have shown an association between some Vitamin D receptor polymorphisms and calcium kidney stone disease.

MAIN OBJECTIVE

To study the possible association between calcium kidney stone disease with bone metabolism and some Vitamin D receptor polymorphisms.

PATIENTS AND METHODS

This is a case-control study, with seventy-two subjects of both genders divided into two groups: Group I: cases, composed by 51 patients suffering from calcium kidney stone disease. Twenty-four of them had no hypercalciuria, 16 had absortive hypercalciuria and 11 had renal hypercalciuria. Group II: controls, composed by 21 people, without either urolithiasis or hypercalciuria. We performed a complete study including biochemical markers of bone mineral remodelling, bone mineral density (BMD) was estimated both in the lumbar spine (L2-L4) and femoral neck, and also VDR polymorphism for the loci b, a and t.

RESULTS

Patients with urolithiasis had lower values of BMD both in the lumbar spine and femoral neck, compared to controls. Z-score were lower in the lumbar spine and femoral neck (p =0,045 y 0,031, respectively). Those patients with absorptive hypercalciuria had higher BMD in the femoral neck than those with renal hypercalciuria and non-hypercalciuria. Because they had more weight and height all the statistical study was performed alter adjusting by these two variables and statistical significance was then only stated between patients with hypercalciuria and without it. Patients with urolithiasis had higher values of 1,25 (OH)2 vitamin D (p=0,002), and lower of PTH (p=0,049), without any relationship to hypercalciuria and its subtypes. Seventy six percent of the patients had a daily calcium intake lower than 800 mg/day. The distribution of VDR alleles in patients with urolithiasis was similar to controls, although after grouping genotypes, a lower distribution of BB and tt polymorphisms were observed in patients suffering from urolithiasis.

CONCLUSIONS

Calcium kidney stone disease by itself produces a decrease in BMD, more intense in femoral neck, independently the presence or absence of hypercalciuria. Patients suffering from urolitihiasis have higher values of 1,25 (OH)2 vitamin D than non-hypercalciuric patients and lower values of PTH probably due to a low dietary calcium intake. In our population studied there is no relationship between VDR polymorphisms and the presence of calcium kidney stone disease. Because the reduced number of patients of our study, more studies are needed to obtain definitely conclusions.

Role of activator protein-1 on the effect of arginine-glycine-aspartic acid containing peptides on transforming growth factor-β1 promoter activity

While arginine-glycine-aspartic acid-based peptidomimetics have been employed for the treatment of cardiovascular disorders and cancer, their use in other contexts remains to be explored. Arginine-glycine-aspartic acid-serine induces Transforming growth factor-beta1 transcription in human mesangial cells, but the molecular mechanisms involved have not been studied extensively. We explored whether this effect could be due to Activator protein-1 activation and studied the potential pathways involved. Addition of arginine-glycine-aspartic acid-serine promoted Activator protein-1 binding to its cognate sequence within the Transforming growth factor-beta1 promoter as well as c-jun and c-fos protein abundance. Moreover, this effect was suppressed by curcumin, a c-Jun N terminal kinase inhibitor, and was absent when the Activator protein-1 cis-regulatory element was deleted. Activator protein-1 binding was dependent on the activity of integrin linked kinase, as transfection with a dominant negative mutant suppressed both Activator protein-1 binding and c-jun and c-fos protein increment. Integrin linked kinase was, in turn, dependent on Phosphoinositol-3 kinase activity. Arginine-glycine-aspartic acid-serine stimulated Phosphoinositol-3 kinase activity, and Transforming growth factor-beta1 promoter activation was abrogated by the use of Phosphoinositol-3 kinase specific inhibitors. In summary, we propose that arginine-glycine-aspartic acid-serine activates Integrin linked kinase via the Phosphoinositol-3 kinase pathway and this leads to activation of c-jun and c-fos and increased Activator protein-1 binding and Transforming growth factor-beta1 promoter activity. These data may contribute to understand the molecular mechanisms involved in the cellular actions of arginine-glycine-aspartic acid-related peptides and enhance their relevance as these products evolve into clinical therapeutic use.

Imaging and speciation of trace elements in biological environment

Mineral elements, often at the trace level, play a considerable role in physiology and pathology of biological systems. Metallogenomics, metalloproteomics, and metallomics are among the emerging disciplines which are critically dependent on spatially resolved concentration maps of trace elements in a cell or tissue, on information on chemical speciation, and on that on metal-binding coordination sites. The mini-review discusses recent progress in analytical techniques for element profiling on the genome scale, biological trace element imaging, and probing, identification and quantification of chemical species in the biological environment. Imaging of the element distribution in cells and tissue sections is becoming possible with sub-micrometer spatial resolution and picogram-level sensitivity owing to advances in laser ablation MS, ion beam and synchrotron radiation X-ray fluorescence microprobes. Progress in nanoflow chromatography and capillary electrophoresis coupled with element specific ICP MS and molecule-specific electrospray MS/MS and MALDI enables speciation of elements in microsamples in a complex biological environment. Laser ablation ICP MS, micro-SXRF, and micro-PIXE allow mapping of trace element distribution in 1D and 2D proteomics gels. The increasing sensitivity of EXAFS and XANES owing to the use of more intense synchrotron beams and efficient focusing optics provide information about oxidation state, fingerprint speciation of metal sites and metal-site structures.

Micro-chemical imaging of cesium distribution in Arabidopsis thaliana plant and its interaction with potassium and essential trace elements

Cesium as an alkali element exhibits a chemical reactivity similar to that of potassium, an essential element for plants. It has been suggested that Cs phytotoxicity might be due either to its competition with potassium to enter the plant, resulting in K starvation, or to its intracellular competition with K binding sites in cells. Such elemental interactions can be evidenced by chemical imaging, which determines the elemental distributions. In this study, the model plant Arabidopsis thaliana was exposed to 1 mM cesium in the presence (20 mM) or not of potassium. The quantitative imaging of Cs and endogenous elements (P, S, Cl, K, Ca, Mn, Fe, and Zn) was carried out using ion beam micro-chemical imaging with 5 microm spatial resolution. Chemical imaging was also evidenced by microfocused synchrotron-based X-ray fluorescence (microXRF) which presents a better lateral resolution (<1 microm) but is not quantitative. Cesium distribution was similar to potassium which suggests that Cs can compete with K binding sites in cells. Cesium and potassium were mainly concentrated in the vascular system of stems and leaves. Cs was also found in lower concentration in leaves mesophyll/epidermis. This late representing the larger proportion in mass, mesophyll/epidermis can be considered as the major storage site for cesium in A. thaliana. Trichomes were not found to accumulate cesium. Interestingly, increased Mn, Fe, and Zn concentrations were observed in leaves at high chlorosis. Mn and Fe increased more in the mesophyll than in veins, whereas zinc increased more in veins than in the mesophyll suggesting a tissue specific interaction of Cs with these trace elements homeostasis. This study illustrates the sensitivity of ion beam microprobe and microfocused synchrotron-based X-ray fluorescence to investigate concentrations and distributions of major and trace elements in plants. It also shows the suitability of these analytical imaging techniques to complement biochemical investigations of metallic stress in plants.

Attention-deficit hyperactivity disorder involves differential cortical processing in a visual spatial attention paradigm

OBJECTIVE

Inattention is undoubtedly one of the main characteristics of Attention-deficit hyperactivity disorder (ADHD). Nevertheless, a growing corpus of evidence shows that not all attentional processes are affected in this condition. This study aimed to explore the distribution of attentional resources in children with ADHD via a spatially shifted double-oddball visual task.

METHODS

We recorded event-related potentials (ERPs) for all visual stimuli. Subjects were instructed to allocate attention in a specific area of visual space while ignoring all stimuli presented outside. Ten male children (age: 9-14; mean = 11.6 +/- 2.1) who met DSM-IV criteria for the ADHD combined subtype participated in the study, along with ten age- and sex-matched healthy controls (9-14; mean = 11.2 +/- 2.3).

RESULTS

ADHD subjects showed late differential cortical responses to initially suppressed irrelevant stimuli. The amplitude of early N1-P1 components were mainly modulated by stimulus location and showed no significant differences between groups, but a late P300-like positivity was clearly evoked in the ADHD group by peripheral stimuli.

CONCLUSIONS

These results suggest that ADHD may not compromise the early attentional spatial filter but rather entails a different distribution of attentional resources at later stages of cortical processing. Perhaps these differences may be attributable to individual differences in attentional mechanisms.

SIGNIFICANCE

ADHD may not affect initial focusing of visual attention but rather the allocation of processing resources in later stages.

Radical surgery-peritonectomy and intraoperative intraperitoneal chemotherapy for the treatment of peritoneal carcinomatosis in recurrent or primary ovarian cancer

BACKGROUND AND OBJECTIVES

Advanced ovarian cancer typically spreads in a diffuse intra-abdominal fashion. This characteristic suggests that combined radical surgery and intraperitoneal chemotherapy may be a useful treatment procedure. The purpose of this study was to review patients submitted to surgical debulking and hyperthermic intraoperative intraperitoneal chemotherapy (HIIC) and to evaluate the potential prognostic survival factors for advanced epithelial ovarian cancer in our center.

METHODS

A series of patients (N = 33) diagnosed of peritoneal carcinomatosis for epithelial ovarian cancer (stage III) from January 1997 to December 2004 submitted to radical surgery-peritonectomy and HIIC with paclitaxel was included in this study; 19 primary ovarian cancer and 14 recurrent ovarian cancer.

RESULTS

Cytoreduction R0 (P = 0.018) and negative lymph nodes (P = 0.005) were covariables for major prognostic survival. Patients with optimal cytoreduction R0 obtained survival rates of 63% at 5 years in recurrent ovarian cancer and 60% in primary ovarian cancer, 71% and 63%, respectively with associated subtotal infra-abdominal peritonectomy, and even better results if negative lymph nodes.

CONCLUSIONS

Radical surgery-peritonectomy with HIIQ has been shown to be a surgical procedure with high tolerability, low morbimortality, enhanced survival, and prolonged disease-free interval in patients with peritoneal carcinomatosis so much for recurrent or primary ovarian cancer.

An interdisciplinary approach to investigate the impact of cobalt in a human keratinocyte cell line

Since in nuclear power plants, risks of skin contact contamination by radiocobalt are significant, we focused on the impact of cobalt on a human cutaneous cell line, i.e. HaCaT keratinocytes. The present paper reports an interdisciplinary approach aimed at clarifying the biochemical mechanisms of metabolism and toxicity of cobalt in HaCaT cells. Firstly, a brief overview of the used instrumental techniques is reported. The following parts present description and discussion of results concerning: (i) toxicological studies concerning cobalt impact towards HaCaT cells (ii) structural and speciation fundamental studies of cobalt-bioligand systems, through X-ray absorption spectroscopy (XAS), ab initio and thermodynamic modelling (iii) preliminary results regarding intracellular cobalt speciation in HaCaT cells using size exclusion chromatography/inductively coupled plasma-atomic emission spectroscopy (SEC/ICP-AES) and direct in situ analysis by ion beam micropobe analytical techniques.

Epileptic seizures caused by low valproic acid levels from an interaction with meropenem

A 55-year-old woman was diagnosed with pneumonia and was treated with meropenem; 5 days later she developed epileptic seizures. She had been treated with valproic acid for 16 years to control her epileptic seizures. Her serum valproic acid concentration was low during treatment with meropenem than previously recorded despite an increase of valproic dose. As soon as administration of meropenem was withdrawn, valproic acid concentration increased to previous levels and her seizures stopped. Meropenem decreases valproic acid concentration, and may promote the development of epileptic seizures in previously controlled epileptic patients. The acute lowering of serum valproate produced by meropenem probably precludes their concomitant use.

[Causes of reoperations in patients with lumbar spinal stenosis treated with instrumentations]

OBJECTIVE

In present study we analyze the causes leading to reoperation patients treated for lumbar spinal stenosis with laminectomy and lumbar instrumentation.

MATERIAL AND METHODS

74 patients operated between January of 1996 and December of 2000 with a minimum 4 year follow-up were seleted for the study.

RESULTS

16 patients (21.1%) underwent a new surgical intervention. The main cause for reoperation was stenosis of the adjacent level superiorly to the instrumentation (in 50%). Other causes were radicular fibrosis, persistence of stenosis after the surgery, neuropatic pain, failure of the instrumentation system, transpedicular screws misplacement and break of screws.

CONCLUSIONS

Complications related with the initial surgical procedure are low, as half of the reoperations were due to stenosis of the segment superior to the fixation.

Leptonic and charged kaon decay modes of the phi meson measured in heavy-ion collisions at the CERN super proton synchrotron

We report on results of a measurement of meson production in central Pb-Au collisions at E(lab) = 158A GeV. For the first time in the history of high energy heavy-ion collisions, phi mesons were reconstructed both in the K+K- and the dilepton decay channels in the same experiment. This measurement yields rapidity densities near midrapidity, from the two decay channels, of 2.05 +/- 0.14(stat) +/- 0.25(syst) and 2.04 +/- 0.49(stat) +/- 0.32(syst), respectively. The shape of the measured transverse momentum spectrum is also in close agreement in both decay channels. The data rule out a possible enhancement of the phi yield in the leptonic over the hadronic decay channel of a factor 1.6 or larger at the 95% C.L. This rules out the discrepancy reported in the literature between measurements of the hadronic and dimuon decay channels by two different experiments.

Melatonin reduces apoptosis and necrosis induced by ischemia/reperfusion injury of the pancreas

The pancreas is highly susceptible to the oxidative stress induced by ischemia/reperfusion (IR) injury leading to the generation of acute pancreatitis. Melatonin has been shown to be useful in the prevention of the damage by ischemia-reperfusion in liver, brain, myocardium, gut and kidney. The aim of the study was to evaluate the cytoprotective properties of melatonin against injury induced by IR in pancreas. The obstruction of gastro-duodenal and inferior splenic arteries induced pancreatic IR in male Wistar rats. Melatonin was intraperitoneally administered before or/and after IR injury. The animals were killed at 24 and 48 hr after reperfusion and there were evaluated parameters of oxidative stress (lipoperoxides, superoxide dismutase, catalase, glutathione peroxidase and reduced glutathione), glandular endocrine and exocrine function (lipase, amylase, insulin) and cell injury (apoptosis and necrosis). The IR induced a marked enhancement of oxidative stress and impaired pancreatic function. The histological analysis showed that IR induced acute pancreatitis with the accumulation of inflammatory infiltrate, disruption of tissue structure, cell necrosis and hemorrhage. Melatonin administration before or after pancreatic IR prevented all tissue markers of oxidative stress, biochemical and histological signs of apoptosis and necrosis, and restored glandular function. No histological signs of pancreatitis were observed 48 hr after reperfusion in 80% of the animals treated with melatonin, with only a mild edematous pancreatitis being observed in the remaining rats. Preventive or therapeutic administration of melatonin protected against the induction of oxidative stress and tissue injury, and restored cell function in experimental pancreatic IR in rats.

Multicentre trials review process by research ethics committees in Spain: where do they stand before implementing the new European regulation?

OBJECTIVES

To review the performance of research ethics committees (RECs) in Spain in assessing multicentre clinical trial (MCT) drug protocols, and to evaluate if they would comply with the requirements of the new EU Directive to be implemented by May 2004.

DESIGN AND SETTING

Prospective study of applications of MCT submitted to RECs.

MAIN MEASUREMENTS

Protocol related features and evaluation process dynamics.

RESULTS

187 applications (24 protocols, 18 study drugs) to be performed in 114 centres, were reviewed by 62 RECs. RECs had a median number of 14 members, of which three were lay members. All applications were approved except four which were however approved by the other RECs involved. The median times from submission to approval and from submission to reception at the sponsor's offices were 48 and 62 days, respectively. In 55% (101/183) of all applications approved, 41 RECs raised 307 queries, 40% of these were protocol related issues, and 38% related to the patients' information sheets. RECs charging an evaluation fee in advance and applications with no queries raised were statistically significantly associated with shorter evaluation times. However, there is a gap of at least 1.5 weeks between the date of the meeting and the reception of the approval letter in the sponsor's office.

CONCLUSIONS

Evaluating MCT protocols by RECs is a time consuming process. Needing 1.5 weeks for communicating the decision taken by RECs to the sponsor suggests serious administrative shortcomings within most RECs. By significantly reducing the time for communication of their decisions, the majority of RECs would comply with the Directive requirement of a maximum 60 day period for the assessment of MCT.

Subperiosteal leiomyosarcoma of the tibia

Primary leiomyosarcoma of bone is a rare malignant tumor of smooth muscle. We report a case of low-grade subperiosteal primary bone leiomyosarcoma in the tibial diaphysis, which radiologically appeared to be osteoid osteoma. A 35-year-old man presented with a several-year history of a palpable hard nodule in the distal left leg, which had enlarged and become painful over the previous 2 years. Radiographs showed solid periosteal reaction with a well-defined lytic lesion in the posteromedial cortical border of the left tibial diaphysis. Computed tomography demonstrated a small, well-defined lytic lesion, not calcified, in a subperiosteal location, surrounded by solid periosteal bone formation. The lesion was excised en bloc and the histological diagnosis of a low-grade leiomyosarcoma was made. To the best of our knowledge, the surface location of primary bone leiomyosarcoma has not been previously described in the literature.

Utilizing Expert Panels in Agricultural Safety and Health Research

This article reports on the use of expert panels by Purdue University's Agricultural Safety and Health Program staff to address three separate research questions related to: (1) developing strategies for the prevention of flowing grain engulfments, (2) evaluation of commercial lifts used by operators with restricted mobility to gain access to agricultural tractors and equipment, and (3) identifying essential competencies for youth enrolled in federally mandated tractor and machinery certification programs. Advantages and disadvantages associated with the use of expert panels are addressed, and specific examples of outcomes are presented. Recommendations for using expert panels during research projects are also included.

Reference level for patient dose in dental skull lateral teleradiography

The present work describes an experiment to obtain a local reference dose value in lateral skull teleradiography for dental applications. The reference value was based on patient measurements in seven dental X-ray units, using thermoluminescent chips, and measurements on a rubber globe filled with water at another 78 installations. Dosemeters were located initially in the head and neck of a human phantom to select the most suitable locations, and on the cephalostat of the X-ray unit at two appropriate locations, which did not interfere with the patient or with the usual imaging routine. The skin projection of the Porion point was considered the best position. 523 patients were monitored in the seven units; then patient doses and dose values from measurements on rubber balloons were compared to normalize and combine the data. The provisional reference value proposed is 400 microGy.

Study of the antibody response against Mycobacterium tuberculosis antigens in Warao Amerindian children in Venezuela

This study was aimed at investigating alternate methods for serodiagnosis of tuberculosis (TB), which are needed because bacteriologic diagnosis of childhood TB is difficult. A selection of 80 serum and saliva samples were tested from Warao indigenous children under 15 years of age; 34 high TB suspects (28 positive and 6 negative for the tuberculin skin test, TST) and 46 healthy contact children (32 positive and 14 negative for the TST). Several enzyme-linked immunosorbent assay (ELISA) serological tests were developed to test for Mycobacterium tuberculosis-specific antibodies, including serum IgA, IgG, IgE, and secretory IgA (sIgA) in saliva against 3 specific antigens (PPD, HSP60, 38 kDa). Of these, 2 antigens, PPD and 38 kDa, showed significantly higher reactivity. The sensitivity and specificity of these tests for diagnosis remained limited, between 26.5% and 38.2%, and 77.4% and 97%, respectively. Of all the samples studied and combinations realized between all isotypes and antigens combined with 3 isotypes (anti-PPD IgG, IgE, and anti-38kDa sIgA) managed to detect the largest number of patients, showing an improved sensitivity level of 64.7%, although specificity levels dropped to 81.8%. These results were compared with the Omega diagnostics commercial kit results. The commercial kits showed significantly lower reactivity (sensitivity of 20% and 13.33% to Myco G and Complex Plus, respectively) and a specificity of 100%. This study shows that in indigenous populations of Venezuela, where invasive procedures cannot be used to select samples but evaluation with a chest X-ray for radiological studies is available, the combination of 3 specific isotypes may be a useful tool to increase diagnostic accuracy with pulmonary TB in this population, when used together with clinical and epidemiological criteria.

[Acute renal failure in a patient with myelodysplastic syndrome and paroxysmal nocturnal hemoglobinuria phenotype]

Hemoglobin and myoglobin heme pigments and iron have acute and chronic nephrotoxic effects, which are often associated with massive hemolysis and rhabdomyolysis. We report a patient with a myelodysplastic syndrome and paroxysmal nocturnal hemoglobinuria phenotype who developed an acute renal failure after a severe haemolytic crisis. There was not evidence of renal vascular pathology, urinary tract obstruction or prerenal factors. Renal biopsy showed features of acute tubular necrosis, with extended iron deposits in tubule cell cytoplasm and tubulo-interstitial fibrosis and atrophy. The patient was oliguric requiring hemodialisys during three weeks, recovering renal function on the fourth week after admission. This case underlines the nephrotoxic role of heme pigment and iron, and possible pathophysiologic mechanisms involved in acute and chronic toxicity of both agents are reviewed.