Prospective Assessment of Bone Metabolism Biomarkers and Survival in Metastatic Castration-resistant Prostate Cancer Patients Treated with Radium-223: The PRORADIUM Study

BACKGROUND

Radium-223 is an active therapy option for bone metastatic castration-resistant prostate cancer (mCRPC). The lack of adequate biomarkers for patient selection and response assessment are major drawbacks for its use.

OBJECTIVE

To assess the prognostic value of bone metabolism biomarkers (BMBs) in ra-223-treated mCRPC patients.

DESIGN, SETTING, AND PARTICIPANTS

A prospective cohort study of mCRPC patients treated with Ra-223 (PRORADIUM study: NCT02925702) was conducted.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The main objective of the study was to evaluate the association between high (≥median) baseline values in at least three bone formation (bone alkaline phosphatase [BAP] and C-terminal type-I collagen propeptide) and bone resorption (N-terminal telopeptide and pyridinoline) biomarkers, and survival. The independent prognostic value of each BMB was also assessed. The association with time to radiographic, clinical, and prostate-specific antigen (PSA) progression; time to skeletal-related events; and PSA response were secondary objectives. Multivariable (MV) Cox-regression models were evaluated.

RESULTS AND LIMITATIONS

A total of 169 patients were included. Of the patients, 70.4% received Ra-223 in second/third line; 144 (85.2%) were Eastern Cooperative Oncology Group 0-1, 126 (74.6%) were in pain, and 80 (47.5%) had more than ten bone metastases. Sixty-seven (39.6%) patients had elevation in at least three BMBs. The median overall survival was 12.1 mo (95% confidence interval [CI]: 10-14.7). No association was observed with other treatment-related secondary outcome parameters. Patients with high values in three or more BMBs had significantly worse survival (9.9 vs 15.2 mo; hazard ratio [HR]: 1.8 [95% CI: 1.3-2.5]; p < 0.001) in the univariate analysis, but not independent in the MV analysis (HR: 1.33; 95% CI: 0.89-2; p = 0.181). High baseline BAP was the only biomarker associated with survival in the MV model (HR: 1.89; 95% CI: 1.28-2.79; p = 0.001). Addition of BAP to the MV clinical model increased the area under the receiver operating characteristic curve 2-yr value from 0.667 to 0.755 (p = 0.003).

CONCLUSIONS

Biomarkers of bone formation, especially BAP, have prognostic value in mCRPC patients treated with radium-223. Its predictive value remains to be assessed, ideally in prospective, adequately powered, randomised clinical trials.

PATIENT SUMMARY

In this study, we evaluate the role of bone metabolism biomarkers to help improve the use of radium-223 as therapy for advanced prostate cancer. We found that bone alkaline phosphatase may be a suitable tool.

Impact of concurrent tumor events on the prostate cancer outcomes of germline BRCA2 mutation carriers

BACKGROUND

Several studies have reported the association of germline BRCA2 (gBRCA2) mutations with poor clinical outcomes in prostate cancer (PCa), but the impact of concurrent somatic events on gBRCA2 carriers survival and disease progression is unknown.

PATIENTS AND METHODS

To ascertain the role of frequent somatic genomic alterations and histology subtypes in the outcomes of gBRCA2 mutation carriers and non-carriers, we correlated the tumour characteristics and clinical outcomes of 73 gBRCA2 and 127 non-carriers. Fluorescent in-situ hybridisation and next-generation sequencing were used to detect copy number variations in BRCA2, RB1, MYC and PTEN. Presence of intraductal and cribriform subtypes was also assessed. The independent impact of these events on cause-specific survival (CSS), metastasis-free survival and time to castration-resistant disease was assessed using cox-regression models.

RESULTS

Somatic BRCA2-RB1 co-deletion (41% versus 12%, p < 0.001) and MYC amplification (53.4% versus 18.8%, p < 0.001) were enriched in gBRCA2 compared to sporadic tumours. Median CSS from diagnosis of PCa was 9.1 versus 17.6 years in gBRCA2 carriers and non-carriers, respectively (HR 2.12; p = 0.002), Median CSS in gBRCA2 carriers increased to 11.3 and 13.4 years in the absence of BRCA2-RB1 deletion or MYC amplification, respectively. Median CSS of non-carriers decreased to 8 and 2.6 years if BRCA2-RB1 deletion or MYC amplification were detected.

CONCLUSIONS

gBRCA2-related prostate tumours are enriched for aggressive genomic features, such as BRCA2-RB1 co-deletion and MYC amplification. The presence or absence of these events modify the outcomes of gBRCA2 carriers.

PTEN loss as a potential biomarker in patients with castration resistant prostate cancer M0

e17043

Background: Until 2018, there were no approved agents for high risk non-metastatic castration-resistant prostate cancer (nmCRPC). Recently, three second-generation anti-androgens (apalutamide, enzalutamide and darolutamide), in combination with ADT, have demonstrated a significant benefit in metastasis-free survival (MFS) and overall survival.According to conventional imaging, nmCRPC state is the opposite to mCRPC. Nevertheless, CRPC is a continuous in which nmCRPC may share similar biology and biomarkers such as PTEN loss, which has proven to be a useful and targetable biomarker in mCRPC. Methods: We performed a prospective and multicenter analysis of 77 patients (pts) with nmCRPC. We collected blood samples as well as prostate cancer diagnostic biopsy whenever they were available. The aim of this study is to find potential biomarkers that could identify pts at a higher risk of metastasis development. Here we report preliminary results according to PTEN status. Results: We have analyzed 32 patients for PTEN loss. We report preliminary results using an IHC assay based on the IPATENTIAL150 PTEN score. Median age was 66 years and 50% of patients had a Gleason score > 8 irrespectively of PTEN status. We identified 24 patients (75%) with PTEN loss with a median PSA at diagnosis of 13,1 ng/ml, and a PSA doubling time (PSA-DT) of 6,3 months vs. 37,35 ng/ml and 3,5 months respectively in the PTEN non-loss pts. In the PTEN loss population, 9 pts (37,5%) did not receive any local treatment vs. 2 pts in the PTEN non-loss (25%). Mediantime from diagnosis to CRPC was 11.5 vs 8.0 yrs in PTEN loss vs. non-loss pts. In the PTEN loss population 2 patients received apalutamide plus ADT and 2 darolutamide plus ADT, these patients were excluded for the MFS analysis. Median MFS was 37 months in the PTEN loss population vs. 23 months in the PTEN non-loss. However, with a median follow-up of 38 months, 54% of PTEN loss pts had developed metastasis and 50% of PTEN non-loss pts. Skeleton was by far the first site of metastasis in PTEN non-loss pts (75%), while PTEN loss pts developed metastasis in lymph nodes (38,5%) nearly as much as in the skeleton (46%). Conclusions: To our knowledge, this is the first data of PTEN loss as a biomarker in nmCRPC. In our study, PTEN loss in primary tumor is more frequent than previously documented for mCRPC. PTEN loss appears to provide a better prognosis and higher lymph node involvement. Further analysis will be performed to corroborate these results and identify other factors involved.

Dear and Glorious Physician, who are we in COVID-19?

We are on the brink of a public health crisis. Science is changing, medicine is evolving, politics are adapting as we are attempting to retain our “normal lives”. The origin of COVID-19 is not exclusively a medical or scientific one. Rather, it lingers more towards damaged public policies with a global pandemic surfacing as merely a consequence of failed economic and health strategies. In this paper we provide a narrative review of the evolution of COVID-19 with emphasis on the its origin and the place of physicians in an ethical perspective.

Phase II pilot study of the prednisone to dexamethasone switch in metastatic castration-resistant prostate cancer (mCRPC) patients with limited progression on abiraterone plus prednisone (SWITCH study)

BACKGROUND

Despite most metastatic castration-resistant prostate cancer (mCRPC) patients benefit from abiraterone acetate plus prednisone 5 mg bid (AA + P), resistance eventually occurs. Long-term use of prednisone has been suggested as one of the mechanisms driving resistance, which may be reversed by switching to another steroid.

METHODS

SWITCH was a single-arm, open-label, single-stage phase II study. The primary objective was to evaluate the antitumour activity of abiraterone acetate plus dexamethasone 0.5 mg daily (AA + D) in mCRPC patients progressing to AA + P. Clinically stable mCRPC patients who had prostate-specific antigen (PSA) and/or limited radiographic progression after at least 12 weeks on AA + P, were eligible. The primary endpoint was measured as the proportion of patients achieving a PSA decline of  ≥ 30% (PSA30) from baseline after 6 weeks on AA + D. Secondary endpoints included: PSA50 response rate at 12 weeks, time to biochemical and radiological progression, overall survival, safety profile evaluation, benefit from subsequent treatment lines and the identification of biomarkers of response (AR copy number, TMPRSS2-ERG status and PTEN expression).

RESULTS

Twenty-six patients were enrolled. PSA30 and PSA50 were 46.2% and 34.6%, respectively. Median time to biochemical and radiological progression were 5.3 and 11.8 months, respectively. Two radiological responses were observed. Median overall survival was 20.9 months. Patients with AR gain detected in plasma circulating tumour DNA did not respond to switch, whereas patients with AR normal status benefited the most. No significant toxicities were observed and PSA50 response rate to subsequent taxane was 50%.

CONCLUSIONS

In selected clinical stable mCRPC patients with limited disease progression on AA + P, a steroid switch from prednisone to dexamethasone can lead to PSA and radiological responses.

International Nosocomial Infection Control Consortium report, data summary of 50 countries for 2010-2015: Device-associated module

BACKGROUND

We report the results of International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2010-December 2015 in 703 intensive care units (ICUs) in Latin America, Europe, Eastern Mediterranean, Southeast Asia, and Western Pacific.

METHODS

During the 6-year study period, using Centers for Disease Control and Prevention National Healthcare Safety Network (CDC-NHSN) definitions for device-associated health care-associated infection (DA-HAI), we collected prospective data from 861,284 patients hospitalized in INICC hospital ICUs for an aggregate of 3,506,562 days.

RESULTS

Although device use in INICC ICUs was similar to that reported from CDC-NHSN ICUs, DA-HAI rates were higher in the INICC ICUs: in the INICC medical-surgical ICUs, the pooled rate of central line-associated bloodstream infection, 4.1 per 1,000 central line-days, was nearly 5-fold higher than the 0.8 per 1,000 central line-days reported from comparable US ICUs, the overall rate of ventilator-associated pneumonia was also higher, 13.1 versus 0.9 per 1,000 ventilator-days, as was the rate of catheter-associated urinary tract infection, 5.07 versus 1.7 per 1,000 catheter-days. From blood cultures samples, frequencies of resistance of Pseudomonas isolates to amikacin (29.87% vs 10%) and to imipenem (44.3% vs 26.1%), and of Klebsiella pneumoniae isolates to ceftazidime (73.2% vs 28.8%) and to imipenem (43.27% vs 12.8%) were also higher in the INICC ICUs compared with CDC-NHSN ICUs.

CONCLUSIONS

Although DA-HAIs in INICC ICU patients continue to be higher than the rates reported in CDC-NSHN ICUs representing the developed world, we have observed a significant trend toward the reduction of DA-HAI rates in INICC ICUs as shown in each international report. It is INICC's main goal to continue facilitating education, training, and basic and cost-effective tools and resources, such as standardized forms and an online platform, to tackle this problem effectively and systematically.

Real-world paliperidone palmitate data from acute units: The SHADOW study

Introduction

There is an increasing interest in understanding how antipsychotic treatments work in a real-world-setting. This is especially important with long-acting-antipsychotics, where explanatory trials may not always represent the real-world-population. Observational studies and pragmatic-clinical trials could provide additional information about new therapies, which could inform decision-making processes.

Objectives

To assess the effectiveness of Paliperidone-Palmitate(PP) in an acute setting within real-world-conditions. Functionality, satisfaction with treatment and pattern of use were also evaluated.

Methods

An observational, prospective 6-week follow-up study was performed in acute units including adult patients with acute exacerbation of schizophrenia that started treatment with PP. Data were collected from initiation of PP until week-6 (or patient's discharge if earlier). Clinical-Global Inventory-Severity (CGI-S) was used to assess effectiveness as well as changes in illness severity. Other outcomes included total score on the Personal and Social Performance scale (PSP), patient-satisfaction with medication (MSQ) and tolerability. Student's-t tests were used to assess changes from baseline in CGI-S and PSP.

Results

Two hundred and eighty patients were included in the analysis (mean age: 40.5 ± 12.2 [SD] years). A significant decrease in mean (SD) CGI-S score between baseline (4.7 [0.9]) and endpoint (3.3 [0.9]) (P < 0.0001) was observed. (Note that 21% of patients were discharged on PP-monotherapy). Patient-functioning also significantly improved from baseline to endpoint (P < 0.0001). Seventy-four percent of patients were satisfied (measured by MSQ) at the end of follow-up. Anticholinergic-treatment was less frequent for PP discharged on monotherapy vs. not monotherapy (12.5% vs 21.2% respectively). Overall, PP was well-tolerated. Twenty-five AEs were reported in 20 patients (incidence 7.1%). No serious AEs occurred.

Conclusions

These results support the effectiveness and tolerability of PP in an acute setting under daily-clinical-practice with good acceptance by patients.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Genomewide Association Study of Tacrolimus Concentrations in African American Kidney Transplant Recipients Identifies Multiple CYP3A5 Alleles

We previously reported that tacrolimus (TAC) trough blood concentrations for African American (AA) kidney allograft recipients were lower than those observed in white patients. Subtherapeutic TAC troughs may be associated with acute rejection (AR) and AR-associated allograft failure. This variation in TAC troughs is due, in part, to differences in the frequency of the cytochrome P450 CYP3A5*3 allele (rs776746, expresses nonfunctional enzyme) between white and AA recipients; however, even after accounting for this variant, variability in AA-associated troughs is significant. We conducted a genomewide association study of TAC troughs in AA kidney allograft recipients to search for additional genetic variation. We identified two additional CYP3A5 variants in AA recipients independently associated with TAC troughs: CYP3A5*6 (rs10264272) and CYP3A5*7 (rs41303343). All three variants and clinical factors account for 53.9% of the observed variance in troughs, with 19.8% of the variance coming from demographic and clinical factors including recipient age, glomerular filtration rate, anticytomegalovirus drug use, simultaneous pancreas-kidney transplant and antibody induction. There was no evidence of common genetic variants in AA recipients significantly influencing TAC troughs aside from the CYP3A gene. These results reveal that additional and possibly rare functional variants exist that account for the additional variation.

HGF/c-Met signaling promotes liver progenitor cell migration and invasion by an epithelial-mesenchymal transition-independent, phosphatidyl inositol-3 kinase-dependent pathway in an in vitro model

Oval cells constitute an interesting hepatic cell population. They contribute to sustain liver regeneration during chronic liver damage, but in doing this they can be target of malignant conversion and become tumor-initiating cells and drive hepatocarcinogenesis. The molecular mechanisms beneath either their pro-regenerative or pro-tumorigenic potential are still poorly understood. In this study, we have investigated the role of the HGF/c-Met pathway in regulation of oval cell migratory and invasive properties. Our results show that HGF induces c-Met-dependent oval cell migration both in normal culture conditions and after in vitro wounding. HGF-triggered migration involves F-actin cytoskeleton reorganization, which is also evidenced by activation of Rac1. Furthermore, HGF causes ZO-1 translocation from cell-cell contact sites to cytoplasm and its concomitant activation by phosphorylation. However, no loss of expression of cell-cell adhesion proteins, including E-cadherin, ZO-1 and Occludin-1, is observed. Additionally, migration does not lead to cell dispersal but to a characteristic organized pattern in rows, in turn associated with Golgi compaction, providing strong evidence of a morphogenic collective migration. Besides migration, HGF increases oval cell invasion through extracellular matrix, a process that requires PI3K activation and is at least partly mediated by expression and activation of metalloproteases. Altogether, our findings provide novel insights into the cellular and molecular mechanisms mediating the essential role of HGF/c-Met signaling during oval cell-mediated mouse liver regeneration.

Hematocele secondary to rupture of an abdominoscrotal hydrocele

OBJECTIVE

To describe one case of hematocele secondary to rupture of an abdominoscrotal hydrocele in an adult patient.

METHODS AND RESULTS

We report a huge hematocele in a patient with this unusual type of hydrocele that suffered a minimal scrotal trauma. It was a hydrocele that extended through the inguinal canal to the retroperitoneal space.

CONCLUSIONS

Abdominoscrotal hydrocele is a rare condition in children and even rarer in adults. The presence of a hematocele requires early surgical treatment.

Percutaneous tibial nerve stimulation in treatment of overactive bladder: when should retreatment be started?

OBJECTIVE

To study the response to posterior tibial nerve stimulation in patients with overactive bladder refractory to medical treatment.

METHODS

A cohort of 53 patients were treated by posterior tibial nerve stimulation and followed up for a maximum of 24 months. All patients completed the International Consultation on Incontinence Modular Questionnaire-Short Form quality of life questionnaire and kept a urination diary to record the daytime urination frequency and night-time urination frequency. Urodynamic studies were also conducted.

RESULTS

At 6 months of follow-up, a cure/improvement rate of 92.4% (49 of 53 cases) had been achieved. Ten patients were given additional treatment and were excluded from subsequent follow-up analysis. At 12 months of follow-up, a cure/improvement rate of 91.69% had been achieved (39 of 43). At 24 months of follow-up, of the 16 patients initially included during the first year, a cure/improvement rate of 62.5% had been achieved (10 of 16). The first sensation of bladder filling had increased by the end of treatment, with differences observed before and after posterior tibial nerve stimulation (P ≤ .001). The average post-treatment bladder capacity had increased by 72.7 mL compared with the initial value (P ≤ .001). At 24 months of follow-up, the group of 16 patients evaluated recorded a significant worsening of night-time urination frequency (P ≤ .05) and quality of life (P ≤ .01).

CONCLUSION

Posterior tibial nerve stimulation is a good option for the treatment of overactive bladder. In our series, the optimal point to start retreatment would be at 24 months after therapy completion.

Barbagli's dorsal urethroplasty. Analysis of results and factors for success

OBJECTIVES

Dorsal urethroplasty as described by Barbagli has gained wide acceptance in the treatment of urethral stricture, given the simplification afforded by obtaining a free graft versus a flap. We present a series of 50 patients treated in our department of urethral stricture by dorsal onlay free graft urethroplasty (Barbagli's technique), in combination or not to other techniques in more complex strictures.

METHODS

The average age of patients was 48.8 years (23-77), the mean follow up 42.9 months (12-96) and the most frequently observed etiology has been the inflammatory urethral stricture (50%).

RESULTS

Overall success rate was 82% (41 cases) and failure 18% (9 cases). In the longer follow-up group, there was a slight drop in success rate of 80% (24 cases) without any significant differences between groups (p= 0.9). Analyzing the variables length of free graft (p= 0.50, p> 36= 0.53), age (p= 0.12, p>36= 0.59), etiology of stricture (p= 0.77, p>36 = 0.77) and type of graft used (p=0.24, p>36= 0.38) did not show any influence on the final outcome of surgery, both in the total sample and the subgroup with follow-up > 36 months. The location of the stricture in bulbar urethra has shown better functional outcome than those operated on for strictures affecting also other urethral locations (p= 0.001) maintaining that result in the group of longer follow up (p>36= 0,001). The lack of treatment prior to urethral surgery has influenced the success of it, since 90.6% of patients without prior treatment before urethroplasty have seen a good functional outcome, compared to treatment prior to surgery that obtained a 66.7% (p= 0.03). This significance is also demonstrated in the group of follow-up > 36 months (p>36= 0.01).

CONCLUSION

The dorsal onlay free graft urethroplasty is a versatile and reproducible technique with acceptable results which allows combination with other techniques when the stenosis extends to the penile urethra. In exceptional cases of panurethral strictures secondary to lichen sclerosus when there is no significant spongiofibrosis and an acceptable urethral plate, can be applied to the whole urethra.

A timing-of-birth effect on multiple sclerosis clinical phenotype

BACKGROUND

A month-of-birth (MOB) effect has been shown in multiple sclerosis (MS).

METHODS

Our chi(2) analyses looked at whether this MOB effect differed by MS phenotype ("bout onset," "primary progressive").

RESULTS

The MOB effect was derived from "bout onset" MS patients (May/November ratio = 1.43; chi(2) = 17.32, df = 1, p = 0.000032).

CONCLUSIONS

An unspecified environmental effect in early development can influence both multiple sclerosis susceptibility and phenotype.

Role of elastic fibers in cooling-induced relaxation

The objective of this work was to confirm the main role of elastic fibers in differing responses of certain vessels during cooling from 37 to 8 degrees C. Previous results have shown that the nature of the vessel (conduit vessel vs muscular vessel) determines the different behavior (dilatation vs contraction) of isolated vessel segments when temperature decreases from 37 to 8 degrees C. In this work, it has been demonstrated that vessels with a great amount of elastic fibers show a dilatation when cooling. On the other hand, muscular vessels with fewer elastic fibers, such as the renal artery, undergo a contraction. The output of calcium from intracellular stores causes contraction of the renal artery during cooling. In this vessel, vasodilatation occurs only when mechanisms of smooth muscle contraction are inactive, as is the case with vessels that have undergone a cold storage period of 48 h. The results presented in this work confirm that there are two main effects, which directly depend on the vessel origin. In conduit arteries, the decrease of temperature induces a vascular relaxation, dependent on the elastic component of the vessel wall. In muscular vessels, the predominant effect is cooling-induced contraction due to an increase of intracellular calcium. This cooling-induced contraction needs the vessel to be in optimal conditions with an active metabolism of the muscular cells. These results are a crucial issue in the sense of explaining several biomedical mechanisms where hypothermia is implicated. The type of vessel implicated in procedures, such as isolated organ perfusion, extracorporeal circulation, and bypass surgery, must be taken into account.

Albumin-derived advanced glycation end-products trigger the disruption of the vascular endothelial cadherin complex in cultured human and murine endothelial cells

Endothelial cell (EC) junctions regulate in large part the integrity and barrier function of the vascular endothelium. Advanced glycation end-products (AGEs), the irreversibly formed reactive derivatives of non-enzymic glucose-protein condensation reactions, are strongly implicated in endothelial dysfunction that distinguishes diabetes- and aging-associated vascular complications. The aim of the present study was to determine whether AGEs affect EC lateral junction proteins, with particular regard to the vascular endothelial cadherin (VE-cadherin) complex. Our results indicate that AGE-modified BSA (AGE-BSA), a prototype of advanced glycated proteins, disrupts the VE-cadherin complex when administered to ECs. AGE-BSA, but not unmodified BSA, was found to induce decreases in the levels of VE-cadherin, beta-catenin and gamma-catenin in the complex and in total cell extracts, as well as a marked reduction in the amount of VE-cadherin present at the cell surface. In contrast, the level of platelet endothelial cell adhesion molecule-1 (PECAM-1), which is located at lateral junctions, was not altered. Supplementation of the cellular antioxidative defences abolished these effects. Finally, the loss of components of the VE-cadherin complex was correlated with increases in vascular permeability and in EC migration. These findings suggest that some of the AGE-induced biological effects on the endothelium could be mediated, at least in part, by the weakening of intercellular contacts caused by decreases in the amount of VE-cadherin present.

Activation of caspases occurs downstream from radical oxygen species production, Bcl-xL down-regulation, and early cytochrome C release in apoptosis induced by transforming growth factor beta in rat fetal hepatocytes

Most of the morphologic changes that are observed in apoptotic cells are caused by a set of cysteine proteases (caspases) that are activated during this process. In previous works from our group we found that treatment of rat fetal hepatocytes with transforming growth factor beta1 (TGF-beta1) is followed by apoptotic cell death. TGF-beta1 mediates radical oxygen species (ROS) production that precedes bcl-xL down-regulation, loss of mitochondrial transmembrane potential, release of cytochrome c, and activation of caspase-3 (Herrera et al., FASEB J 2001;15:741-751). In this work, we have analyzed how TGF-beta1 activates the caspase cascade and whether or not caspase activation precedes the oxidative stress induced by this factor. Our results show that TGF-beta1 activates at least caspase-3, -8, and -9 in rat fetal hepatocytes, which are not required for ROS production, glutathione depletion, bcl-xL down-regulation, and initial cytochrome c release. However, caspase activation mediates cleavage of Bid and Bcl-xL that could originate an amplification loop on the mitochondrial events. An interesting result is that transmembrane potential disruption occurs later than the initial cytochrome c release and is mostly blocked by the pan-caspase inhibitor Z-VAD.fmk, indicating that the decrease in mitochondrial transmembrane potential (Delta(Psi)m) may be a consequence of caspase activity rather than the mechanism by which TGF-beta induces cytochrome c efflux. Finally, although Z-VAD.fmk completely blocks nucleosomal DNA fragmentation, it only delays cell death, which suggests that activation of the apoptotic program by TGF-beta in fetal hepatocytes inevitably leads to death, with or without caspases.

Activation of p38MAPK by TGF-beta in fetal rat hepatocytes requires radical oxygen production, but is dispensable for cell death

We have previously found that transforming growth factor-beta (TGF-beta) induces an increase in radical oxygen species (ROS) production that mediates its apoptotic effects in fetal hepatocytes. In this paper we show that TGF-beta activates p38 mitogen-activated protein kinase (p38MAPK) and ROS may be responsible for this activation. Activation of p38MAPK occurs late, coincident with the maximal production of ROS, it is inhibited by radical scavengers and it is accentuated by the presence of glutathione synthesis inhibitors. However, p38MAPK does not appear to be involved in any of the apoptotic events: loss of Bcl-x(L) levels, cytochrome c release, cleavage of caspase substrates and loss of cell viability.

Reactive oxygen species (ROS) mediates the mitochondrial-dependent apoptosis induced by transforming growth factor (beta) in fetal hepatocytes

Treatment of fetal rat hepatocytes with transforming growth factor beta (TGF-beta) is followed by apoptotic cell death. Analysis of radical oxygen species (ROS) content and mitochondrial transmembrane potential (Deltapsim), using specific fluorescent probes in FACScan and confocal microscopy, showed that TGF-beta mediates ROS production that precedes the loss of Deltapsim, the release of cytochrome c, and the activation of caspase 3. TGF-beta induces a decrease in the protein and mRNA levels of bcl-xL, an antiapoptotic member of the Bcl-2 family. In contrast, there is no change in the expression and/or translocation of Bax, a proapoptotic member of the same family. EGF maintains Bcl-xL, preventing Deltapsim collapse and release of cytochrome c. The presence of radical scavengers blocks the decrease in bcl-xL levels, Deltapsim collapse, cytochrome c release, and activation of caspase 3; in contrast, the presence of glutathione synthesis inhibitors such as BSO accentuated the effect. The incubation of fetal hepatocytes in the presence of ter-butyl-hydroperoxide alone produces a decrease in bcl-xL. These results indicate that during the apoptosis mediated by TGF-beta in fetal hepatocytes, ROS may be responsible for the decrease in bcl-xL mRNA levels that precedes the loss of Deltapsim, the release of cytochrome c, and the activation of caspase 3, culminating in cell death.

Perfusate lactate dehydrogenase level and intrarenal resistance could not be adequate markers of perfusion quality during isolated kidney perfusion

The main goal of this work was to study the influence of perfusion pressure and flow waveform during kidney perfusion, and the relationship between renal vascular resistance (RVR) and lactate dehydrogenase (LDH) concentration in the perfusate. Simultaneous constant pressure kidney perfusions were performed with either pulsatile or continuous flow at either 30 or 80 mm Hg of constant perfusion pressure. Mean flow, pressure, and RVR were displayed online during perfusion. Perfusate samples for LDH, creatine phosphatase kinase (CPK), and alkaline phosphatase (AP) determinations were taken. At the end of the perfusion, 2 ml of Evans blue was injected into the circuit to obtain images of perfusate distribution, and the kidneys were weighed. Also, hematoxylin/eosine studies were performed, showing more Bowman's space and tubular dilation in kidneys perfused with high pressure. We did not find differences in RVR between kidneys perfused at 30 and 80 mm Hg; nevertheless, perfusate distribution was better in the 80 mm Hg perfusions. We did not find any correlation between enzyme release and RVR in kidneys perfused with different mean pressures. These findings suggest that vascular resistance and LDH concentration cannot be independently considered as adequate markers of perfusate distribution.

Epidermal growth factor impairs the cytochrome C/caspase-3 apoptotic pathway induced by transforming growth factor beta in rat fetal hepatocytes via a phosphoinositide 3-kinase-dependent pathway

Transforming growth factor beta (TGF-beta)-mediated apoptosis is one of the major death processes in the liver. We have previously shown that epidermal growth factor (EGF) is an important survival signal for TGF-beta-induced apoptosis in fetal hepatocytes (Fabregat et al., FEBS Lett 1996;384:14-18). In this work we have studied the intracellular signaling implicated in the protective effect of EGF. We show here that EGF activates p42 and p44 mitogen-activated protein kinases (MAPK). However, mitogen extracellular kinase (MEK) inhibitors do not block the survival effect of EGF. EGF also activates phosphoinositide 3-kinase (PI 3-kinase) and protein kinase B (PKB/AKT) in these cells. The presence of PI 3-kinase inhibitors blocks the protective effect of EGF on cell viability, DNA fragmentation, and caspase-3 activity. We have found that TGF-beta disrupts the mitochondrial transmembrane potential (DeltaPsi(m))( )and activates the release of cytochrome c, this effect being blocked by EGF, via a PI 3-kinase-dependent pathway. A detailed study on bcl-2 superfamily gene expression shows that TGF-beta produces a decrease in the messenger RNA (mRNA) and protein levels of bcl-x(L), an antiapoptotic member of this family, capable of preventing cytochrome c release. EGF is able to maintain bcl-x(L) levels even in the presence of TGF-beta. PI 3-kinase inhibitors completely block the protective effect of EGF on TGF-beta-induced bcl-x(L )down-regulation. We conclude that PI 3-kinase mediates the survival effect of EGF on TGF-beta-induced death by acting upstream from the mitochondrial changes, i.e., preventing bcl-x(L) down-regulation, cytochrome c release, and activation of caspase-3.

Paradoxical effects of temperature on vascular tone

Temperature may have significant influence on vascular tone in such cases as organ preservation, coronary bypass surgery, and extracorporeal circulation. The aim of this research was to study the direct effect of temperature variation on vascular tone in an attempt to elucidate the mechanisms involved. In a first series of experiments, the isometric tension of two different vessels (rat thoracic aorta and pig renal branch artery) was studied at different temperatures. To study the role of calcium in this response, a second series of experiments was performed. In this the vessels were incubated with the intracellular chelator BAPTA/AM. Further experiments were performed to test the effect of cold storage. Our results show that changes in temperature lead to different results in pig renal artery and rat aorta. A decrease in temperature induced a highly reproducible relaxation in rat aorta, whereas pig renal artery presented cooling-induced contraction. Moreover, whereas calcium depletion failed to inhibit cooling-induced relaxation in rat aorta, it did not provoke cooling-induced contraction in pig renal artery. Similar responses were obtained with cold storage and calcium depletion. We intend to demonstrate that, just as the effect of temperature variation on pig renal artery is due to a metabolic mechanism, its effect on rat aorta may be due to structural factors. This hypothesis is supported by the result of histological studies which demonstrate a higher proportion of elastin fibres in rat aorta than in pig renal artery.

Regulation of endothelial nitric oxide synthase expression by albumin-derived advanced glycosylation end products

We examined whether albumin-derived advanced glycosylation end products (AGEs) downregulate the expression of endothelial nitric oxide synthase (NOS). Significant reductions in NOS activity and cGMP levels in bovine aortic endothelial cells were observed when exposed to different concentrations of albumin-derived AGEs. Western and Northern blot analyses showed significant decreases at the protein and transcript levels. Both reductions became evident after 24 hours of exposure. Nuclear run-on assays showed that AGE-BSA did not modify the transcription rate of the NOS III gene; however, AGE-BSA treatment markedly reduced the half-life of NOS III mRNA. In addition, AGE-treated endothelial cells displayed significant reduction on their antiplatelet properties. These results indicate that NOS expression is reduced by AGEs by increasing the rate of mRNA degradation and may be relevant to the impairment of some endothelial functions observed in diabetes and aging. The full text of this article is available at http://www.circresaha.org.

Ethnic differences in N-glucuronidation of nicotine and cotinine

We previously reported that the metabolism of cotinine, the proximate metabolite of nicotine, is significantly slower in black than in white cigarette smokers. To understand why the metabolism of nicotine and cotinine might differ between blacks and whites, we studied the pattern of nicotine metabolism in blacks and whites. One hundred eight healthy smokers (51 blacks and 57 whites), of similar age, gender distribution, and smoking history, received an i.v. infusion of deuterium-labeled nicotine and cotinine. The clearance of cotinine, the fractional conversion of nicotine to cotinine, and the metabolic clearance of nicotine to cotinine were significantly lower in blacks than in whites. Blacks excreted significantly less nicotine as nicotine-N-glucuronide and less cotinine as cotinine-N-glucuronide than whites, but there was no difference in the excretion of 3'-hydroxycotinine-O-glucuronide. Nicotine and cotinine glucuronidation appeared to be polymorphic, with evidence of slow and fast N-glucuronide formers among blacks but was unimodal with fast conjugators only among whites. Other findings of note included the demonstration of a significant correlation between the distribution volumes of nicotine and cotinine with lean body mass: there was a smaller distribution volume and a shorter half-life for cotinine in women than in men and a smaller volume of distribution of cotinine in blacks than in whites. We conclude that the metabolism of cotinine is slower in blacks than in whites because of both slower oxidative metabolism of nicotine to cotinine (presumably via cytochrome P-450 2A6) and slower N-glucuronidation. Ethnic differences in the metabolism of other drugs undergoing N-glucuronidation should be studied.

Nicotine metabolism and intake in black and white smokers

CONTEXT

Racial differences in tobacco-related diseases are not fully explained by cigarette-smoking behavior. Despite smoking fewer cigarettes per day, blacks have higher levels of serum cotinine, the proximate metabolite of nicotine.

OBJECTIVE

To compare the rates of metabolism and the daily intake of nicotine in black smokers and white smokers.

DESIGN

Participants received simultaneous infusions of deuterium-labeled nicotine and cotinine. Urine was collected for determination of total clearance of nicotine and cotinine, fractional conversion of nicotine to cotinine, and cotinine elimination rate. Using cotinine levels during ad libitum smoking and clearance data, the daily intake of nicotine from smoking was estimated.

SETTING

Metabolic ward of a university-affiliated public hospital.

PARTICIPANTS

A total of 40 black and 39 white smokers, average consumption of 14 and 14.7 cigarettes per day, respectively, of similar age (mean, 32.5 and 32.3 years, respectively) and body weight (mean, 73.3 and 68.8 kg, respectively).

MAIN OUTCOME MEASURES

Clearance (renal and nonrenal), half-life, and volume of distribution of nicotine and cotinine and the calculated daily intake of nicotine.

RESULTS

The total and nonrenal clearances of nicotine were not significantly different, respectively, in blacks (17.7 and 17.2 mL x min(-1) x kg(-1)) compared with whites (19.6 and 18.9 mL x min(-1) x kg(-1)) (P=.11 and .20). However, the total and nonrenal clearances of cotinine were significantly lower, respectively, in blacks (0.56 and 0.47 mL x min(-1) x kg(-1)) than in whites (0.68 vs 0.61 mL x min(-1) x kg(-1); P=.009 for each comparison). The nicotine intake per cigarette was 30% greater in blacks compared with whites (1.41 vs 1.09 mg per cigarette, respectively; P=.02). Volume of distribution did not differ for the 2 groups, but cotinine half-life was higher in blacks than in whites (1064 vs 950 minutes, respectively; P = .07).

CONCLUSIONS

Higher levels of cotinine per cigarette smoked by blacks compared with whites can be explained by both slower clearance of cotinine and higher intake of nicotine per cigarette in blacks. Greater nicotine and therefore greater tobacco smoke intake per cigarette could, in part, explain some of the ethnic differences in smoking-related disease risks.

Carpal tunnel syndrome heralding polymyalgia rheumatica

Presenting symptoms in polymyalgia rheumatica (PMR) may be atypical. We report herein two old females who developed a bilateral carpal tunnel syndrome several months before the typical symptoms of PMR appeared. In both patients the diagnosis of PMR was overlooked and a surgical release of the median nerve was performed. PMR should be considered in elderly people who develop an acute or subacute carpal tunnel syndrome.

[Echographic parameters in the evaluation of the degree of portal hypertension]

We did a prospective study in thirty one patients with ascites who were hospitalized at Cayetano Heredia Hospital (H.N.C.H.). We investigated the association and correlation between ultrasonographic parameters of portal hypertension (HTP) and the presence and level of HTP (determinate by the serum-to-ascites albumin concentration gradient). In our study, we demonstrated that ultrasonographic splenomegaly studied by longitudinal diameter of the spleen discriminate patients with HTP with a high positive predictive value (94.4%), although it didn't happen with transverse diameter of the spleen. However patients with elevated measurements of high GRAD-Alb (> or = 2.35 +/- 0.05 g/dl) had alterations in the transversal diameter of the spleen with a high negative predictive value (91.7%), these findings were suggested its use like a parameter for reject high levels of HTP. In our study, we demonstrated that the existence of changes at diameters of portal vein and splenic vein could not discriminate patients with HTP. By the way, we didn't find association between degree of high GRAD-Alb and the different splenic measurements.

[Prevalence of drinkers at risk and associated factors among men attending primary care clinics]

OBJECTIVES

To quantify the prevalence of risk drinkers among men seeking health care, establish consumption patterns and relate them to socio-demographic features and health habits.

DESIGN

Crossover study. First phase of an experimental study.

SETTING

Four primary care teams in Area 10, Madrid.

PATIENTS

Males between 18 and 65 who attended for on-demand medical care. A systematic sample was selected (n = 562).

MEASUREMENTS

A questionnaire collecting socio-demographic characteristics, health habits and alcohol consumption (frequency, consumption pattern, intake of Weekly Units of alcohol (WU) and alcohol-related problems). 94.2% replied. 38% were habitual drinkers (drink four or more days a week), while 18.9% were week-end drinkers. Prevalence of drinkers consuming over 21 WU was 24.8%; and over 35 WU, 16.2%. Whether the cut-off point was fixed at 21 or 35 WU. The alcohol taken was related to educational level, physical exercise, smoking and taking other drugs. On average, single people, smokers, other drug-consumers, ex-drinkers and habitual drinkers were those who displayed most problems connected with alcohol consumption.

CONCLUSIONS

There is a similar profile of health habits for the groups consuming over 21 WU and 35 WU, which should make preventive care pay attention to both groups of drinkers.

[Follow-up of the patient with HIV infection: a hospital task?]

OBJECTIVE

To assess how often patients with HIV infection abandon treatment.

DESIGN

Longitudinal, prospective and observational study. SITE. Out-patient Hospital Clinic.

PATIENTS AND OTHERS PARTICIPANTS

The total number of patients with HIV infection treated between September 1989 and December 1990.

INTERVENTIONS

Assessment of the level of out-patient follow-up.

MEASUREMENTS AND MAIN RESULTS

The rate of abandonment of out-patient follow-up was determined, with "abandonment" defined as unexplained non-attendance for at least two consecutive appointments. Its possible correlations with sex, age and HIV risk behaviour was calculated. 182 patients (143 men and 39 women) with an average age of 30.1 (ds 8.62) were surveyed. The abandonment rate for the sample as a whole was 44%, with no difference as to sex. However the abandonment rate was higher in the group of patients addicted to drugs (DDA) (69%) than in non-DDA (25%) or in ex-DDA patients (6.5%). These figures reached high statistical significance (p less than 0.01 and 0.001 respectively.

CONCLUSIONS

The abandonment rate of out-patient hospital follow-up by HIV-infected patients appears extremely high, especially among drug addicts (DDA).

[Effect of labor on the acid-base equilibrium of the newborn infant]

The values of pH, PCO2, PO2 and base excess were measured at the time of birth, from the umbilical artery, in a group of 19 normal newborn infants from vaginal deliveries and compared to 19 infants born by elective cesarean sections without labor. The value of pH was significantly lower (7.23 +/- 0.06) in vaginal deliveries compared to elective cesarean sections (7.27 +/- 0.03) p less than 0.01. The best correlations occurred between pH and PCO2 (r: 0.72 p less than 0.01) in vaginal deliveries and pH and base excess (0.73 p less than 0.01) in cesarean sections. Normal values for umbilical arterial pH should consider the influence of labor in the acid base balance of the newborn infant. We consider that pH value under 7.11 (mean -2 SD) in vaginal deliveries and under 7.21 in elective cesarean sections are indicative of neonatal acidosis.