Targeting DNA2 overcomes metabolic reprogramming in multiple myeloma

DNA damage resistance is a major barrier to effective DNA-damaging therapy in multiple myeloma (MM). To discover mechanisms through which MM cells overcome DNA damage, we investigate how MM cells become resistant to antisense oligonucleotide (ASO) therapy targeting Interleukin enhancer binding factor 2 (ILF2), a DNA damage regulator that is overexpressed in 70% of MM patients whose disease has progressed after standard therapies have failed. Here, we show that MM cells undergo adaptive metabolic rewiring to restore energy balance and promote survival in response to DNA damage activation. Using a CRISPR/Cas9 screening strategy, we identify the mitochondrial DNA repair protein DNA2, whose loss of function suppresses MM cells' ability to overcome ILF2 ASO-induced DNA damage, as being essential to counteracting oxidative DNA damage. Our study reveals a mechanism of vulnerability of MM cells that have an increased demand for mitochondrial metabolism upon DNA damage activation.

IL-1β-mediated inflammatory signaling drives ineffective erythropoiesis in early-stage myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are a group of incurable hematopoietic stem cell (HSC) neoplasms characterized by peripheral blood cytopenias and a high risk of progression to acute myeloid leukemia. MDS represent the final stage in a continuum of HSCs' genetic and functional alterations and are preceded by a premalignant phase, clonal cytopenia of undetermined significance (CCUS). Dissecting the mechanisms of CCUS maintenance may uncover therapeutic targets to delay or prevent malignant transformation. Here, we demonstrate that DNMT3A and TET2 mutations, the most frequent mutations in CCUS, induce aberrant HSCs' differentiation towards the myeloid lineage at the expense of erythropoiesis by upregulating IL-1β-mediated inflammatory signaling and that canakinumab rescues red blood cell transfusion dependence in early-stage MDS patients with driver mutations in DNMT3A and TET2 . This study illuminates the biological landscape of CCUS and offers an unprecedented opportunity for MDS intervention during its initial phase, when expected survival is prolonged.

Abstract 6053: Sulfation is required for prostate cancer xenograft tumor formation but is dispensable for cell viabilityin vitro

Sulfation of proteins, carbohydrates, lipids, and xenobiotics is an essential post-translational modification (PTM) process thought to play critical roles in diverse biological processes ranging from detoxification, cell signaling, and extracellular matrix architecture, to immune modulation. Sulfation is accomplished by the universal sulfate donor, PAPS (3'-Phosphoadenosine-5'-phosphosulfate), which is synthesized by bifunctional enzymes PAPSS1 and PAPSS2 (PAPS synthases). The PAPSS2 gene situates near PTEN and is frequently deleted with PTEN across cancer types. Approximately 20% of prostate cancer patients exhibit loss of PTEN, and ~50% of these cases also sustain a loss of PAPSS2. However, the loss of PAPSS2 appears to be tolerated and possibly compensated by its functionally redundant paralogue, PAPSS1, located on chromosome 4q24. The functional redundancy between PAPSS1 and PAPSS2 suggests that these two genes may be collateral lethality pair provided that sulfation is essential for cancer cell viability. Thus, we hypothesize that targeting PAPSS1 in PTEN/PAPSS2-null prostate cancer can generate cancer-specific vulnerabilities while leaving normal cells undisturbed. To assess this possibility, knockdown and knockout of PAPSS1 in cell lines of PAPSS2-null and PAPSS2-wildtype background were generated to characterize cell viability in vitro and tumor formation in vivo. PAPS and APS, an intermediary product of the sulfation pathway, are measured to verify that no alternative pathways for sulfate donors exist and that the co-extinction of PAPSS1/2 eliminates all avenues of generating sulfate donors. Combined extinction of PAPSS1/2 across multiple cancer cell lines was shown to be tolerated in vitro, and recurrent changes in morphology were observed. Loss of sulfation verified by the disappearance of sulfotyrosine and mass spectrometry measurements of PAPS and APS are pending. Our In vitro results surprisingly indicate that a major PTM, like sulfation is entirely dispensable for cancer cell viability under normal culture conditions. However, PAPSS1/2-null cell lines demonstrated a profound delay in tumor formation and prolonged survival, suggesting that sulfation may be required for stromal and innate immune modulation.

Citation Format: Ko-Chien Chen, Yonhong Liu, Chenchu Lin, Er-Yen (Nick) Yen, Francesca Citron, Xingdi Ma, Tan Lin, Philip Lorenzi, Florian Muller, Ronald DePinho. Sulfation is required for prostate cancer xenograft tumor formation but is dispensable for cell viabilityin vitro [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6053.

Targeting DNA2 Overcomes Metabolic Reprogramming in Multiple Myeloma

DNA damage resistance is a major barrier to effective DNA-damaging therapy in multiple myeloma (MM). To discover novel mechanisms through which MM cells overcome DNA damage, we investigated how MM cells become resistant to antisense oligonucleotide (ASO) therapy targeting ILF2, a DNA damage regulator that is overexpressed in 70% of MM patients whose disease has progressed after standard therapies have failed. Here, we show that MM cells undergo an adaptive metabolic rewiring and rely on oxidative phosphorylation to restore energy balance and promote survival in response to DNA damage activation. Using a CRISPR/Cas9 screening strategy, we identified the mitochondrial DNA repair protein DNA2, whose loss of function suppresses MM cells' ability to overcome ILF2 ASO-induced DNA damage, as being essential to counteracting oxidative DNA damage and maintaining mitochondrial respiration. Our study revealed a novel vulnerability of MM cells that have an increased demand for mitochondrial metabolism upon DNA damage activation.

STATEMENT OF SIGNIFICANCE

Metabolic reprogramming is a mechanism through which cancer cells maintain survival and become resistant to DNA-damaging therapy. Here, we show that targeting DNA2 is synthetically lethal in myeloma cells that undergo metabolic adaptation and rely on oxidative phosphorylation to maintain survival after DNA damage activation.

Abstract A059: Tackling the tumor microenvironment with CD38 blockade to enhance cancer immunotherapy

The single agent or the combination of anti-PD-1, anti-PD-L1, and anti-CTLA-4 is an effective strategy that is being clinically explored to treat a variety of cancer types. Some patients display primary resistance to the treatment, while others relapse after treatment. Resistance is a major issue that needs to be addressed. Using multiple immunocompetent syngeneic and K-rasLA1/+p53R172HΔg/+ spontaneous animal models of lung cancer, we have explored the mechanisms of resistance to treatments by evaluating the molecular and cellular immune profiles of the tumor microenvironment. We observed that tumor-bearing mice treated with PD-1/PD-L1 blocking antibodies developed resistance through the up-regulation of CD38. We also observed this in the combination therapy of anti-PD-1 and anti-CTLA-4, suggesting that CD38 is a major mechanism of resistance to immune checkpoint inhibitors. In vitro and in vivo studies demonstrated that CD38 impacted CD8+ T-cell function via adenosine receptor signaling and dendritic cell-mediated B7 signaling. Antibody-mediated cell depletion assays were conducted to validate the mechanisms. To determine the applicability to patients, we analyzed 793 lung cancer patients’ specimens with immunohistochemistry staining and assessed biomarker relationships in multiple large independent patient databases (~1,900 tumors). Pathologic analysis revealed positive immunohistochemical staining for CD38 on tumor cells in 15-23% of cases, and bioinformatic analyses revealed a strong correlation between CD38 expression and the immune signature. Lastly, targeting CD38 abolished the treatment resistance by modulating the adenosine levels and thereby enhancing the effector immune cell infiltrates into the tumor microenvironment. Based on our study, CD38 blockade improves the efficacy of single-agent anti-PD-1/PD-L1, or with anti-CTLA-4 combination in lung cancer. CD38 could potentially serve as a novel biomarker of resistance for immune checkpoint inhibition. The data from this study provide a unique target, biomarker, and therapeutic strategy that can be translated into the clinical practice.

Citation Format: Limo Chen, Lixia Diao, Xiaohui Yi, Bertha Leticia Rodriguez, Yanli Li, Pamela Villalobos, Tina Cascone, Xi Liu, Lin Tan, Philip Lorenzi, Jared Fradette, David Peng, Ferdinandos Skoulidis, Youhong Fan, Jaime Rodriguez-Canales, Vassiliki Papadimitrakopoulou, Ethan Dmitrovsky, Lauren A Byers, Jing Wang, Ignasio Wistuba, Jim Heymach, Don Gibbons. Tackling the tumor microenvironment with CD38 blockade to enhance cancer immunotherapy [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A059.

RNA-binding proteins RBM20 and PTBP1 regulate the alternative splicing of FHOD3

Regulation of alternative splicing events is an essential step required for the expression of functional cytoskeleton and sarcomere proteins in cardiomyocytes. About 3% of idiopathic dilated cardiomyopathy cases present mutations in the RNA binding protein RBM20, a tissue specific regulator of alternative splicing. Transcripts expressed preferentially in skeletal and cardiac muscle, including TTN, CAMK2D, LDB3, LMO7, PDLIM3, RTN4, and RYR2, are RBM20-dependent splice variants. In the present study, we investigated the RBM20 involvement in post-transcriptional regulation of splicing variants expressed by Formin homology 2 domain containing 3 (FHOD3) gene. FHOD3 is a sarcomeric protein highly expressed in the cardiac tissue and required for the assembly of the contractile apparatus. Recently, FHOD3 mutations have been found associated with heart diseases. We identified novel FHOD3 splicing variants differentially expressed in human tissues and provided evidences that FHOD3 transcripts are specific RBM20 and PTBP1 targets. Furthermore, we demonstrated that the expression of RBM20 and PTBP1 promoted the alternative shift, from inclusion to exclusion, of selected FHOD3 exons. These results indicate that RBM20 and PTBP1 play a role in the actin filament functional organization mediated by FHOD3 isoforms and suggest their possible involvement in heart diseases.

Effects of Charcoal Hemoperfusion with Prostacyclin on the Coagulation-fibrinolysis System and Platelets of Patients with Fulminant Hepatic Failure — Preliminary Observations

The coagulation-fibrinolysis system and platelet function were studied in two patients with fulminant hepatic failure undergoing charcoal hemoperfusion with prostacyclin (PGI2) infusion. There was no adverse effect on the purely coagulative side and significant decreases were found only in Factors V and VII. There was a significant increase in platelet count and initially high BTG values decreased to normal. The findings suggest that PGI2 greatly improves the biocompatibility of hemoperfusion devices.

Defibrotide in Extracorporeal Circulation on Healthy Rabbits

Defibrotide, a partially depolymerized DNA fraction obtained from mammalian lung, was found to have significant antithrombotic and fibrinolytic activities. On the basis of this evidence defibrotide could be of clinical value during hemoperfusive treatment. The present study was designed to evaluate the biological tolerance of this technique in a model of extracorporeal circulation, using an original Silastic apparatus, with defibrotide (0.83 mg/kg–1/min–1 after a 50 mg/kg–1 bolus injection) and heparin (0.66 IU/kg–1/min–1 after a 400 IU/kg–1 bolus injection) in ten rabbits (Group 1) and heparin only in ten others (Group 2, control group). In this study defibrotide produced a significantly lower pressure inside the circuit compared to the control group and gave a protective effect against those pathological changes which appeared during extracorporeal circulation and that may be considered omens of a state of shock. However the use of defibrotide in addition to heparin seemed to have a poor effect on platelet and leukocyte count alterations during application of this technique.

Abstract 2134: Use of methionine gamma-lyase-loaded erythrocytes to induce effective methionine depletion in cancer therapy

Methionine (Met) dependence is a cancer-specific metabolic defect that has emerged as a target during the last two decades. The use of methionine gamma-lyase (MGL; EC number 4.4.1.11), a bacterial Met-catabolizing enzyme, is a promising strategy for treatment of Met-dependent cancers. However, one challenge is that MGL has a very short half-life (~2 hours), resulting in a short-term Met depletion in vivo. Additionally, its cofactor, pyridoxal 5’-phosphate (PLP) is rapidly eliminated from plasma (Yang et al., 2004). PEGylation extends the MGL half-life in mice to up to 38 hours. Nevertheless, frequent injections are still necessary for maintaining an effective Met depletion over time (Sun et al., 2003). In addition, the low bioavailability of PLP remains a major hurdle due to both scavenging by plasma proteins and very short half-life (< 15 minutes) in the blood stream (Zempleni, 1995). Studies showed that pyridoxine (PN), a vitamin B6 vitamer, can easily cross red blood cells (RBCs) membrane to be rapidly converted to PLP via an enzymatic reactions cascade (Anderson et al., 1971). Considering those particular characteristics of RBCs, we propose that RBC-encapsulated MGL (ERY-MET) will protect the enzyme from degradation/immune reactions and therefore overcome the pharmacodynamic limitations for its use in the treatment of Met-dependent cancers. Pharmacokinetics, pharmacodynamics, and safety parameters of MGL-loaded RBCs were evaluated in healthy mice. In parallel, the role of RBC in PLP biosynthesis from exogenous uptake of PN was investigated in vivo. Finally, we investigated the antitumoral effect of repeated injections of MGL-loaded RBCs combined with daily intragastric administration of PN in two subcutaneous xenografted mouse models for human gastric and glioblastoma tumors. The MGL half-life increased from < 24 hours to ~ 10 days when encapsulated in RBC, with no toxicity reported after one injection of ERY-MET. Following intragastric administration (3.2 mg/kg), PN was rapidly (15 minutes) converted into PLP within the RBC, resulting in an increase of MGL activity (holoenzyme). Combining a weekly single intravenous injection of ERY-MET for 5 days, in association with daily PN supplementation by gavage led to a sustained Met depletion in plasma and induced a 85% inhibition of tumor growth 45 days following implantation of glioblastoma cells. In the gastric mouse model, tumor growth was inhibited by 72% at the same time point (45 days).This study clearly demonstrated that encapsulation of MGL in erythrocytes both strongly improved the half-life and contributed to provide active cofactor. In parallel, repeated injections of ERY-MET were effective against tumor growth in mouse models. Thus, due to the RBC intrinsic characteristics, ERY-MET represents a new promising treatment against a broad scope of cancers that rely on Met metabolism.

Citation Format: Fabien Gay, Karine Aguera, Karine Senechal, Philip Lorenzi, Alexander Scheer, Françoise Horand, Vanessa Bourgeaux. Use of methionine gamma-lyase-loaded erythrocytes to induce effective methionine depletion in cancer therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2134. doi:10.1158/1538-7445.AM2017-2134

Abstract 4137: L-asparagine synthetase in solid tumors: Screening and implication in pancreatic cancer

L-Asparaginase (L-Asp) depletes L-Asn in the plasma and is commonly used in the treatment of acute lymphoblastic leukemia (ALL) for over 40 years. Its indication is motivated by the fact that L-asparagine synthetase deficient leukemic cells are unable to synthesize L-Asn to meet metabolic demands and therefore depend on circulating L-asparagine (L-Asn) to survive and to proliferate. Unfortunately, its use in patients with solid tumours failed due to high toxicity. L-Asp entrapped inside red blood cells (GRASPA®) significantly improves its therapeutic index, thus allowing its use with acceptable tolerance in patients with solid tumors.

There is strong rational for plasmatic L-Asn depletion in patients with negative or low-expressing L-asparagine synthetase (ASNS) cancers. Indeed ASNS catalyzes the biosynthesis of L-Asn from L-Aspartate and L-Glutamine and its overexpression appears to be crucial in L-Asp resistance in an ALL cell line model (Aslanian, 2001). In the same way, an inverse causal relationship was observed between ASNS expression (at the protein level) and L-Asp activity in a panel of human ovarian cancer cell lines, and a weak expression of ASNS by immunohistochemistry for 15% of the 55 ovarian cancers tested (Lorenzi, 2006).

To demonstrate the implication of ASNS in solid tumors, we performed a large screening of ASNS expression by tissue microarray in several cancer types (bladder, brain, breast, colon, head & neck, kidney, liver, lung, lymphoma, melanoma, myeloma, ovary, pancreas and prostate).

We first focused on pancreatic tumors and studied ASNS expression on 4 different tissue microarrays (n=172) and on a large series of standard pancreatic tumors slides (n=124). By this indirect immunohistochemistry method, we determine the proportion of low-expressing tumors in a representative subset of human pancreatic ductal adenocarcinomas. In parallel, we evaluate the IC50 of L-Asp in SW1990 (low ASNS expression), PANC-1 and MIA-PaCa-2 (ASNS positive) pancreatic cancer cell lines.

Our results indicate that:

- ASNS expression was strongly decreased in human ductal adenocarcinoma (percentage of negative or low-positive tumors > 65%) as compared to the high-expressing adjacent healthy pancreas tissue (< 10%);

- In vitro, The ASNS low-expressing cell line SW1990 was more sensitive to L-Asp than the PANC-1 and MIA-PaCa-2 ASNS positive cell lines (IC50 (IU/mL L-Asp): 0.07±0.04 versus 0.18±0.05 and 0.24±0.06, respectively).

In conclusion, we demonstrate that ASNS expression is strongly down-regulated in human pancreatic cancer. We also highlight in vitro causality between ASNS status and sensitivity to L-Asp in 3 pancreatic cancer cell lines. According to these results, ASNS was identified as a candidate biomarker to screen patients in solid tumors, especially for pancreatic carcinoma.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4137. doi:10.1158/1538-7445.AM2011-4137

mRNA and microRNA expression profiles of the NCI-60 integrated with drug activities

As part of the Spotlight on Molecular Profiling series, we present here new profiling studies of mRNA and microRNA expression for the 60 cell lines of the National Cancer Institute (NCI) Developmental Therapeutics program (DTP) drug screen (NCI-60) using the 41,000-probe Agilent Whole Human Genome Oligo Microarray and the 15,000-feature Agilent Human microRNA Microarray V2. The expression levels of approximately 21,000 genes and 723 human microRNAs were measured. These profiling studies include quadruplicate technical replicates for six and eight cell lines for mRNA and microRNA, respectively, and duplicates for the remaining cell lines. The resulting data sets are freely available and searchable online in our CellMiner database. The result indicates high reproducibility for both platforms and an essential biological similarity across the various cell types. The mRNA and microRNA expression levels were integrated with our previously published 1,429-compound database of anticancer activity obtained from the NCI DTP drug screen. Large blocks of both mRNAs and microRNAs were identified with predominately unidirectional correlations to approximately 1,300 drugs, including 121 drugs with known mechanisms of action. The data sets presented here will facilitate the identification of groups of mRNAs, microRNAs, and drugs that potentially affect and interact with one another.

Abstract 3051: mRNA and microRNA expression profiles integrated with drug sensitivities of the NCI-60 human cancer cell lines

We present here new NCI-60 profiling studies of mRNA and miRNA expression using the 41,000-probe Agilent Whole Human Genome Oligo Microarray and the 15,000-feature Agilent Human miRNA Microarray V2. Expression levels were determined for ∼21,000 genes and 723 human miRNAs. The resulting data sets are freely available and searchable online at http://discover.nci.nih.gov in our CellMiner relational database package. The profiling included technical replicates, with six and eight cell lines assayed in quadruplicate for mRNA and miRNA, respectively. The remaining cell lines were assayed in duplicate. Our analysis indicates high reproducibility for both platforms and an essential biological similarity across the various cell types. The expression levels were integrated with our previously published 1,429-compound database of anticancer activity in the NCI screen. Large blocks of both mRNAs (∼2000) and miRNAs (∼200) with unidirectional correlation to ∼1300 drugs including 121 drugs with known mechanisms of action were identified. The data sets presented here will facilitate recognition of the groups of mRNAs, miRNAs and drugs that potentially affect and interact with one another.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3051.

Multifactorial regulation of E-cadherin expression: an integrative study

E-cadherin (E-cad) is an adhesion molecule associated with tumor invasion and metastasis. Its down-regulation is associated with poor prognosis for many epithelial tumor types. We have profiled E-cad in the NCI-60 cancer cell lines at the DNA, RNA, and protein levels using six different microarray platforms plus bisulfite sequencing. Here we consider the effects on E-cad expression of eight potential regulatory factors: E-cad promoter DNA methylation, the transcript levels of six transcriptional repressors (SNAI1, SNAI2, TCF3, TCF8, TWIST1, and ZFHX1B), and E-cad DNA copy number. Combined bioinformatic and pharmacological analyses indicate the following ranking of influence on E-cad expression: (1) E-cad promoter methylation appears predominant, is strongly correlated with E-cad expression, and shows a 20% to 30% threshold above which E-cad expression is silenced; (2) TCF8 expression levels correlate with (-0.62) and predict (P < 0.00001) E-cad expression; (3) SNAI2 and ZFHX1B expression levels correlate positively with each other (+0.83) and also correlate with (-0.32 and -0.30, respectively) and predict (P = 0.03 and 0.01, respectively) E-cad expression; (4) TWIST1 correlates with (-0.34) but does not predict E-cad expression; and (5) SNAI1 expression, TCF3 expression, and E-cad DNA copy number do not correlate with or predict E-cad expression. Predictions of E-cad regulation based on the above factors were tested and verified by demethylation studies using 5-aza-2'-deoxycytidine treatment; siRNA knock-down of TCF8, SNAI2, or ZFHX1B expression; and combined treatment with 5-aza-2'-deoxycytidine and TCF8 siRNA. Finally, levels of cellular E-cad expression are associated with levels of cell-cell adhesion and response to drug treatment.

Abstract A120: Cellular inhibition of Chk2 kinase and potentiation of camptothecins and radiation by the novel Chk2 inhibitor PV1019

Chk2 is a checkpoint kinase involved in the ATM pathway, which is activated by genomic instability and DNA damage, leading to either cell death (apoptosis) or cell cycle arrest. Chk2 provides an unexplored therapeutic target against cancer cells. We recently reported NSC 109555 as a novel chemotype Chk2 inhibitor. We have now synthesized a derivative of NSC 109555, PV1019 (NSC 744039), which is a selective sub-micromolar inhibitor of Chk2 in vitro. The co-crystal structure of PV1019 bound in the ATP binding pocket of Chk2 confirmed enzymatic/biochemical observations that PV1019 acts as a competitive inhibitor of Chk2 with respect to ATP. PV1019 was found to inhibit Chk2 in cells. It inhibits Chk2 autophosphorylation (which represents the cellular kinase activation of Chk2), Cdc25C phosphorylation, and HDMX degradation in response to DNA damage. PV1019 also protects normal mouse thymocytes against IR-induced apoptosis, and it shows synergistic antiproliferative activity with topotecan, camptothecin, and radiation in human tumor cell lines. We also show that PV1019 as well as Chk2 siRNA can exert antiproliferative activity themselves in the cancer cells with high Chk2 expression in the NCI60 screen. These data indicate that PV1019 is a potent and selective inhibitor of Chk2 with chemotherapeutic and radiosensitization potential.

Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A120.

Role of patient posture during puncture on successful unilateral spinal anaesthesia in outpatient lower abdominal surgery

BACKGROUND AND OBJECTIVE

Unilateral spinal anaesthesia is a useful anaesthesia technique in lower abdominal surgery, especially in an outpatient setting. Patient posture is pivotal in the achievement of unilateral anaesthesia. Nevertheless, no studies have elucidated the influence of patient posture during the anaesthetic injection on unilaterality. Thus, the aim was to compare the effect of patient posture, during the induction phase of spinal anaesthesia, on block characteristics.

METHODS

Eighty patients, ASA I-II, scheduled for unilateral hernioplasty were randomized into two groups. Anaesthesia was performed in lateral position in Group 1 (G1) with operative side down and in sitting position in Group 2 (G2) whose patients were then immediately turned on their lateral side. All patients were maintained for 20 min in lateral position with their operative side down. Hyperbaric bupivacaine 1% 10 mg were used.

RESULTS

Unilateral anaesthesia was seen in 80% (32/40) and 12.5% (5/40) of G1 and G2, respectively. The readiness for surgery was faster in G1 (P < 0.0001). The motor block in the non-operative side was stronger in G2 (P < 0.0001). The offset of sensory block was faster in G1 (P = 0.0001). The offset of motor block was slower in G1 (P = 0.0008). The time for voiding was shorter in G1, although not significant.

CONCLUSIONS

Lateral posture during the induction of spinal anaesthesia is pivotal for a higher success of unilateral block, a fast readiness to surgery, and a fast recovery. Therefore, this technique can be considered feasible and time-saving for lower abdominal surgery.

Cytological analysis of the distension fluid used during diagnostic office hysteroscopies in patients with suspected endometrial pathology

OBJECTIVE

Evaluation of the feasibility and usefulness of cytological analysis of the distension fluid used during diagnostic office hysteroscopy in patients with suspected endometrial pathology.

METHODS

In 243 consecutive patients undergoing diagnostic hysteroscopy for suspected endometrial pathology a few milliliters of the distension medium used for uterine visualization were collected and sent for cytological analysis. Findings of these "endometrial washings" were compared to visual hysteroscopic impression, endometrial biopsy and uterine histology--when available.

RESULTS

Endometrial washings were considered adequate in 227 patients (93.4%). In 12 cases (5.3%) atypical cells were detected: all of these presented either atypical complex hyperplasia or endometrial cancer at the final histological evaluation of the uterus. Four of the 16 (25%) patients diagnosed with endometrial cancer or atypical complex hyperplasia at the final histopathological analysis of the uterus had inadequate washings. No patient with cancer or atypical hyperplasia had negative cytology.

CONCLUSIONS

Collection and analysis of the distension fluid is feasible and, when positive, has a remarkable value in the diagnosis of endometrial cancer and its precursors.

Modification of ultrasonographically measured endometrial thickness after discontinuation of adjuvant therapy with tamoxifen in postmenopausal breast cancer patients

INTRODUCTION

The aim of this study was to evaluate endometrial changes after five years of tamoxifen treatment by measuring endometrial thickness with transvaginal ultrasonography.

MATERIALS AND METHODS

Fifty-five asymptomatic postmenopausal women who had assumed tamoxifen, 20 mg daily, for five years were controlled six months after discontinuation of the therapy. Of these 42 were followed-up at 12 months. Statistical analysis was performed using the analysis of variance for repeated measures and the Anova test; p < 0.05 was considered statistically significant.

RESULTS

We found a significant reduction in endometrial thickness at six months (p = 0.0046) and at 12 months (p = 0.0003) but not between six and 12 months (p = 0.06).

CONCLUSION

A statistically significant reduction in endometrial thickness after discontinuation of tamoxifen therapy was found. This can probably be attributed to the cessation of the estrogenic side-effects of tamoxifen therapy.

New palladium(II)-catalyzed asymmetric 1,2-dibromo synthesis

[reaction: see text] The oxidation of olefins by chiral monometallic and bimetallic Pd(II)-Cu(II) catalysts in bromide-containing aqueous-THF reaction mixtures produced chiral 1,2-dibromides. With alpha-olefins, the ee's were about 95% while most of the internal alkenes gave somewhat lower enantioselectivities ( approximately 80%).

Breast cancer metastatic to the vulva after local recurrence occurring on a rectus abdominis myocutaneous flap: a case report and review of the literature

INTRODUCTION

Vulvar metastases are the third largest group of malignant tumors of the vulva. We report the tenth case of breast cancer vulvar metastases arising 11 years after the primary diagnosis of breast ductal carcinoma and the first occurring eight years after a local recurrence on a rectus abdominis myocutaneous flap.

CASE REPORT

A 49-year-old woman presented with a voluminous lump of the left labium majus and enlargement of the ipsilateral inguinal lymph nodes. The mass was removed together with the ipsilateral inguinal lymph nodes. Microscopic evaluation of the removed lump revealed massive carcinomatous infiltration. No in situ lesions nor normal breast tissue were identified.

CONCLUSIONS

Unusual breast cancer metastases sites should not be ruled out. Our case differs from the preceding cases because this patient underwent plastic surgery with reconstruction of the breast with a rectus abdominis myocutaneous flap one year after mastectomy and developed a local recurrence three years thereafter. It can be hypothesized that lymphatic spread through newly formed lymphatics occurred.

Haemostatic molecular markers in patients undergoing radical retropubic prostatectomy for prostate cancer and submitted to prophylaxis with unfractioned or low molecular weight heparin

BACKGROUND

Deep vein thrombosis and subsequently pulmonary embolism are the most common causes of increased post-operative morbidity and mortality in patients with pelvic or abdominal cancer. Aim of the study was to evaluate variations in coagulative parameters induced by two accepted primary prophylaxis patterns: standardized low doses of unfractioned heparin (UFH) or single doses of low molecular weight heparin (LMWH) in cancer patients submitted to radical retropubic prostatectomy.

METHODS

Fifty patients (45-75 yr) were randomly assigned two groups. Group 1 received UFH (5000 units s.c. x 3 daily); group 2 received calcium nadroparin (single daily dose of 0.3 ml s.c.). In both groups prophylaxis began preoperatively and was maintained throughout the entire hospital-stay. Blood cell, platelet count, coagulative system exploring tests, thrombotic molecular markers, and physiological inhibitors of coagulation were determined at baseline conditions and on the first and seventh day after surgery.

RESULTS

Preoperative values of fibrinogen, F1+2 fragment, TAT and D-dimer resulted over normal range in both groups. A significant increase of these markers was observed also during the post-operative period. PT, aPTT, ATIII, PC, total and free PS showed the most substantial changes on the 1st post operative day, though their values ranged within normal levels on the three sampling times. The levels of haemostatic markers demonstrated a baseline hypercoagulability, probably related to cancer and thrombin activation caused by prostatectomy. Despite this thrombophylic state, neither of the two groups presented symptomatic bleeding or thromboembolic complications.

CONCLUSIONS

These results prove that a single daily dose of nadroparin has been safe and efficient as a thrice-daily dose of UFH, with a better risk/benefit relationship.

Cloning and functional characterization of the human heterogeneous nuclear ribonucleoprotein type I promoter

We have cloned and functionally characterized a portion of the human hnRNP I (heterogeneous nuclear ribonucleoprotein type I) gene containing the promoter elements. HnRNP I is an alternative splicing modulator of tissue-specific transcripts that is expressed in three different isoforms. The DNA sequence at the transcription start site, identified by 5'-rapid amplification of cDNA ends, shows a high 'GC' content, lacks canonical TATA sequences and contains multiple putative Sp1 and NF1 transcription factor-binding sites, a GATA box and a CAAT box. By means of a chloramphenicol acetyltransferase reporter construct and deletion analyses, we have identified two regions between -770 bp and -206 bp that had a positive effect on expression activity in HeLa cells.

[Applied anatomy of the distal "vinculum tendinis" in the fetlock tendon sheath of the hindlimb in cattle]

A relatively thick (diameter approximately 2 mm), ropelike (length ca. 20 mm) and elastic "Vinculum tendinis" connects--within the fetlock tendon sheath--the dorsal side of the deep digital flexor tendon with the dorsal part of the Manica flexoria (the communicating band of the Musculus interosseous medius to the superficial digital flexor tendon). The extensive fetlock tendon sheath can be involved in diseases such as aseptic and septic inflammations. Spreading of these inflammations makes in some of these cases the partial resection of the tendon of the deep digital flexor muscle and the cutting of these Vincula necessary. The results of this contribution, collected from 60 hindlimbs of adult bovines show variations in number, length, diameter and extent and the inner structure with blood vessels and nerves.

Life crisis and the body within

The authors take into account body involvement during the existential critical periods. The concept of body involvement considers both the biological (organic) involvement of the body, i.e. all the 'psychosomatic' (in a wider sense) dimensions, and the involvement of the mental representation of one's body. This involvement refers to some clinical conditions as 'abnormal somatic styles of existence', hypochondriasis and dysmorphophobia (all grouping in the DSM-IV 'somatoform disorders') and the anorexic states. From a structural psychogenetic point of view, this firm involvement of the body (naturally we are referring to the 'experienced body') is stressed in light of its importance in self identity construction and maintenance, especially when, as in some existential critical periods, identity physiologically faces significant modifications and hazardous movements.

Organization of the human gene encoding heterogeneous nuclear ribonucleoprotein type I (hnRNP I) and characterization of hnRNP I related pseudogene

The human gene hnRNPI encoding the heterogeneous nuclear ribonucleoprotein type I, an alternative splicing modulator of tissue-specific transcripts, also known as PTB (polypyrimidine tract-binding protein), was recently mapped on chromosome 14, as well as on chromosome 19, suggesting that two closely related copies of the same gene might exist in the human genome. We report here that the gene localized on chromosome 14 corresponds to a highly homologous processed pseudogene related to hnRNPI gene (psihnRNPI). Analysis by RT-PCR and by EST database comparison indicates that psihnRNPI is not expressed. In this report we have also analyzed the organization of the actual hnRNPI gene localized on chromosome 19. The DNA sequence at the intron-exon boundaries unveiled the possible mechanism by which three isoforms of the protein (namely hnRNPI, PTB2 and PTB3) are generated by means of alternative splicing of the same hnRNPI gene transcript.

Effects of early antiretroviral treatment on HIV-1 RNA in blood and lymphoid tissue: a randomized trial of double versus triple therapy. Swiss HIV Cohort Study

To assess the effects of early initiation of antiretroviral therapy on cell-free and cell-associated viral load in blood and lymphoid tissue, we performed a randomized, open-label, multicenter trial comparing a double (zidovudine + lamivudine) and triple (zidovudine + lamivudine + ritonavir) drug combination in treatment-naive, asymptomatic patients with CD4 counts >400 cells/microl. HIV-1 RNA was measured in plasma, peripheral blood mononuclear cells, and sequential tonsil or lymph node biopsies (27 patients); the study follow-up was 2 years. Among 42 randomized patients, the proportion with plasma HIV-1 RNA <50 copies/ml was 16% and 74% at week 24 (p<.001) in those randomized to double and triple therapy, respectively, necessitating frequent treatment intensification in the double arm. After a rapid decline within 4 weeks in both arms, cell-associated HIV-1 RNA decreased further only in those patients with sustained suppression of plasma viral load, but remained almost always detectable at low levels, indicating persisting transcription of viral RNA. CD4 counts increased by 200 to 250 cells/microl at week 96 in both arms without significant differences (intent-to-treat analyses). Thus, even if treatment is initiated early in asymptomatic patients with preserved CD4 counts, three drugs are necessary to achieve sustained decreases of HIV load in blood and lymphoid tissue.

Searching for a general anaesthesia protocol for rapid detoxification from opioids

The technique for ultra rapid opioid detoxification is designed to shorten the detoxification period by precipitating withdrawal by the administration of opioid antagonists such as naloxone or naltrexone. This procedure is performed under deep sedation or general anaesthesia to ensure that the patient does not consciously experience the acute withdrawal phase. This strategy has aroused controversy regarding the risk of sedation or anaesthesia in this situation. In the present study, ultra rapid opioid detoxification was carried out in 12 opiate-addicted patients by infusion of naloxone 4 mg for a period of 5 h using controlled ventilation during general anaesthesia, induced and maintained with midazolam, propofol and atracurium. Invasive cardiovascular and respiratory monitoring was performed, and withdrawal signs were evaluated using a graduated scale. Anaesthesia was maintained for another hour after the completion of the naloxone infusion. The validity of this anaesthesia protocol was confirmed by the relative lack of change in the patients' haemodynamic values associated with mild signs of withdrawal.

[Anaphylactic reaction to thiopental. A case documented by tryptase values and RAST]

During general anesthesia adverse reactions are not uncommon, and the hypothesis of an anaphylactic response cannot be excluded. In these situations, a differential diagnosis from other events which often present identical clinical manifestations is necessary. For this purpose measurement of serum tryptase, as a biochemical marker of the release of mast-cell granules, is considered a valuable and specific method, especially if it is carried out on several hematic samples, obtained in successive times, for pointing out the progressive reduction of the values. If an anapyhlactic pathogenesis is confirmed, the identification of the responsible drug is necessary for a safer approach of the patient in view of a further anesthesia. A severe and protracted reaction has been observed after a standard induction of anesthesia, in which measurement of serum tryptase has shown high values of this protease 2 hours after the reaction which a subsequent decrease in the samples repeated after 5, 8, 11 e 20 hours, suggesting an anaphylactic etiology of the reaction. The specific RAST for the substances employed has excluded a role for muscle relaxant, plasma expander and latex, while it was positive for tiopenthal, suggesting in this case a true anaphylactic reaction caused by the hypnotic drug.

Impact of drug resistance mutations on virologic response to salvage therapy. Swiss HIV Cohort Study

OBJECTIVE

To assess the prognostic significance of drug-associated mutations in the protease and reverse transcriptase (RT) genes on virological response to salvage therapy.

PATIENTS

All patients from four centres of the Swiss HIV Cohort Study who were switched, between February and October 1997, to nelfinavir plus other antiretroviral drugs following failure of highly active antiretroviral therapy (HIV-1 RNA >1000 copies/ml after > 3 months).

METHODS

Direct sequencing of RT and protease genes derived from plasma RNA was performed in 62 patients before salvage therapy. Baseline predictors (drug-resistance mutations, drug exposure, clinical and biological parameters) of virological response after 4-12 weeks of therapy were assessed by linear regression analyses.

RESULTS

Patients had been treated with RT inhibitors and protease inhibitors for a median duration of 35.6 and 12.2 months, respectively. Baseline median CD4 cell count was 113 x 10(6)/l and HIV-1 RNA 5.16 log10 copies/ml. The median decrease of HIV-1 RNA was 0.38 log10; 32% of the patients showed > 1 log10 decrease. At baseline, 90% of the patients had RT inhibitor-resistance mutations with a median number per patient of four (range, 0-7). Primary and secondary protease inhibitor-resistance mutations were detected in 69% and 89% of the patients, respectively. The median number of total protease inhibitor-resistance mutations per patient was four (range, 0-9). In univariate analysis, virological response to salvage therapy was associated with number of RT inhibitors, primary and secondary protease inhibitor-resistance mutations, history of protease inhibitor use (duration and number), but not with clinical stage, HIV-1 RNA level or CD4 cell count. After adjustment for all variables, the number of RT inhibitor plus protease inhibitor-resistance mutations was the only independent predictor.

CONCLUSIONS

In patients with advanced HIV infection, the virological response to salvage therapy containing nelfinavir is best predicted by the number of baseline RT inhibitor plus protease inhibitor-resistance mutations.

Antiretroviral therapies in pregnancy: maternal, fetal and neonatal effects. Swiss HIV Cohort Study, the Swiss Collaborative HIV and Pregnancy Study, and the Swiss Neonatal HIV Study

BACKGROUND

Therapies containing two reverse transcriptase inhibitors (RTI) with or without protease inhibitors are used with increasing frequency in pregnant HIV-infected women.

OBJECTIVE

To assess the safety of antiretroviral therapy in pregnant women and their newborns.

METHODS

All clinical events and laboratory abnormalities in pregnant women on RTI with or without protease inhibitors and in their newborns were collected through an observational study.

RESULTS

A total of 37 HIV-infected pregnant women have given birth to 30 children (by 30 April 1998). All received RTI, which were combined with protease inhibitors in 16 cases. Twelve women became pregnant while on treatment. Drugs used were as follows: zidovudine (n = 33), lamivudine (n = 33), stavudine (n = 4), indinavir (n = 9), ritonavir (n = 4), nelfinavir (n = 2) and saquinavir (n = 2). Adverse events during pregnancy were anaemia (n = 15), elevation of transaminases (n = 4), nausea/vomiting (n = 4), glucose intolerance (n = 2), nephrolithiasis (n = 2), diarrhoea (n = 2), hypertension (n = 1), insulin-requiring diabetes (n = 1). Adverse events in neonates were prematurity (n = 10), anaemia (n = 8), cutaneous angioma (n = 2), cryptorchidism (n = 2), transient hepatitis (n = 1). Non-life-threatening intracerebral haemorrhage occurred in a premature baby (33 weeks gestation) exposed during fetal life to zidovudine-lamivudine-indinavir, and in a term baby exposed to stavudine-lamivudine-indinavir. Extrahepatic biliary atresia occurred in one newborn exposed to zidovudine-lamivudine-indinavir. Maternal viral load was below 400 copies/ml in 18 out of 30 patients who delivered. One case of mother-to-child HIV transmission was identified.

CONCLUSIONS

In HIV-infected pregnant women treated with two RTI with or without protease inhibitors, one or more adverse events occurred in 29 out of 37 women and in 14 out of 30 babies. In newborns, frequent prematurity, one case of biliary malformation and one intracerebral haemorrhage in a term baby are of concern. These observations do not preclude combination therapies during pregnancy but emphasize the necessity to maintain updated registers on their safety.

Toxicity, efficacy, plasma drug concentrations and protease mutations in patients with advanced HIV infection treated with ritonavir plus saquinavir. Swiss HIV Cohort Study

OBJECTIVE

To assess the safety, efficacy and plasma drug levels of the combination of ritonavir plus saquinavir for the treatment of advanced HIV infection.

DESIGN

Multicentre pilot study.

PATIENTS

Eighteen protease inhibitor-naive patients, with intolerance or contraindication to reverse transcriptase inhibitors, a median CD4 cell count of 12 x 10(6)/l (range, 1-50 x 10(6)/l), and a median HIV viraemia of 5.25 log10 copies/ml (range, 4.00-6.13 log10 copies/ml).

METHODS

Patients received 600 mg twice daily of both ritonavir and saquinavir. Viraemia was measured at baseline and at weeks 5, 9 and 13. Response was defined as a drop of viraemia of more than 1 log10 at week 5. Plasma drug levels were determined after at least 3 weeks of combined treatment: samples were collected before and 1, 2, and 4 h after the morning ingestion of both drugs. The protease gene was sequenced at baseline and under treatment.

RESULTS

Among the 16 patients evaluable at week 5, 11 were responders, and among these patients, six remained responders at week 13 (two with undetectable viraemia). Study discontinuations were due to side-effects (n = 4), patient choice (n = 3), protocol violation (n = 1) and death (n = 1). Responders had higher drug levels than non-responders (P < 0.01 for saquinavir, P = 0.04 for ritonavir). In two non-responders, development of multiple new mutations at positions 10, 20, 48, 82, 84 and 90 was observed after 5-13 weeks.

CONCLUSION

The response to ritonavir plus saquinavir in advanced HIV infection is unpredictable. A minority of patients respond with disappearance of HIV viraemia. In other patients, rapid cumulative emergence of protease mutations conferring resistance to treatment cannot always be prevented by good compliance and relatively high plasma drug levels.

["Body psychosis": an interpretative hypothesis about some psychiatric disorders]

The authors propose to group some clinical entities as Delusional hypochondria, Dysmorphophobia, Nervous Anorexia, under the term of Body Psychosis. These are considered as psychoses endowed in the body (naturally we are speaking not about the anatomical body, but the phenomenological one, the personal experienced body). The specific clinical frame is justified by the following considerations: 1) in a psychopathological light all the disorders imply an altered relationship with the personal experienced body; 2) in a prognostic light the "experienced body" involvement given specific and common features; 3) clinically a one-other manifestation change is always possible; 4) relationally the human contact (and the medical one too) with this kind of patient got very specific features that often provoke dramatic and perverse changes in the same relation, especially in a sadomasochistic sense. The personal nosological frame is stressed within the actual psychiatric diagnostic classification (ICD 10, DSM IV).

Haemodynamic and haemoximetric aspects of experimental orthotopic liver transplantation: comparison between two different doses of propofol

OBJECTIVE

Evaluation of haemodynamic and gas exchange modifications using propofolnitrous oxide anaesthesia after ketamine induction during experimental orthotopic liver transplantation (OLT).

DESIGN

Measurements of haemodynamic and haemoximetric effects of two anaesthesiological conditions, differing each other for the different dose of propofol, performed in an experimental model characterized by temporary anhepatism followed by revascularization.

SETTING

Surgical experimental laboratory of the University Hospital of Florence.

ANIMALS

Thirty experimental OLT on female pigs (weight 30 +/- 2 kg) were performed.

MEASUREMENTS AND MAIN RESULTS

The following haemodynamic: HR, MAP, MPAP, PCWP, CI, SI, RVSWI, LVSWI, SVR, PVR, RPP and gas-exchange parameters: PaCO2, etCO2, D(aA)CO2, PaO2/PAO2, VD/VTphys, HB, PaO2, SaO2, DO2, O2ER, VO2, SvO2, VO2/DO2 relationship were evaluated. Anaesthesia was induced by ketamine and maintained by N2O and propofol infusion using 0.28 mg x kg(-1)x min(-1) (Group 1) and 0.19mg x kg(-1) x min(-1) (Group 2). During the anhepatic phase we used cavalportal-jugular by-pass (CPJ). Haemodynamic preoperative data confirmed the absence of any myocardial depressant effect at the lower dose of propofol. During the most critical stages of surgery a progressive decrease of CI associated with low values of PCWP was observed. The decrease of etCO2 during the anhepatic phase is due to the VD/VT increase following CI reduction and CO2 production decrease. VO2 decreased significantly during the anhepatic phase and successively increased during the reperfusion phase whereas CI remained low, during both surgical phases. These results demonstrated that VO2 was largely independent from DO2 because cellular O2ER gradually increased as DO2 remained constantly low, thus indicating a good cellular metabolism reuptake. The decrease of SVO2 is related to the decrease of CI and to the increase of VO2 and O2ER.

CONCLUSION

The VO2/DO2 relationship showed a complete O2 supply-non-dependency suggesting an adequate cellular metabolism maintenance during the anhepatic and postanhepatic phases. According to these results, the authors suggest that propofol, within the two different anaesthesiological protocols at two different doses, surely favoured a good cellular perfusion also under low cardiac output conditions, undoubtedly contributing to the realization of stress-resistant conditions and influencing a good recovery and postoperative outcome.

[The concept of metamorphosis in psychopathology]

The authors take into account the psychopathological issue of "metamorphosis" (or transformation of the Self) firstly with the observation of some clinical cases. The psychopathological problem is set as a disorder of the s.c. "awareness of the Self" and considered in the light of a close relationship with the subjective body experience. The clinical discussion on the metamorphosis problem is developed taking also into account the data coming from the anthropological research.

Aspirin effect on early and late changes in acute lung injury in sheep

OBJECTIVE

There have been several studies that have already explored the potential beneficial role of cyclo-oxygenase (CO) inhibitors on oleic acid (OA)-induced lung injury in different species. These studies report no significant effect of CO inhibition, though thromboxane B2 (TxB2) was effectively blocked. However, recent studies indicate that pre-treatment with aspirin (ASA) preserve gas exchange in OA lung injury in dogs. Aim of our study has been to evaluate the potential beneficial effects of the pre-treatment with low doses of ASA on gas exchange, hemodynamics, respiratory mechanics, prostanoids and lung histology in OA-induced lung injury in sheep.

DESIGN

0.09 ml/kg of OA was administered into the right atrium of 14 anaesthetized sheep. Six received a bolus of ASA (10 mg/kg i.v.) 30 min before OA, the others saline as placebo.

MEASUREMENTS AND RESULTS

Pulmonary and tissue gas exchange, pulmonary and systematic hemodynamics, respiratory system mechanics, TxB2 and 6-keto-PGF1 alpha, leukocytes and platelets concentrations were measured throughout the subsequent 3 h and lung histology was effected at end-experiment. The principal findings of our study are: 1) ASA reduces OA-induced early pulmonary vasoconstriction and bronchoconstriction, parallelled by a suppression of TxB2 generation; 2) the late increase in pulmonary artery pressure and airway resistance due to OA is not inhibited by ASA; 3) the early disturbance in pulmonary gas exchange is reduced by ASA, whereas the late severe deterioration is exaggerated by ASA; 4) the stability of tissue exchange ratio (R) at approximately 1 in ASA-group compared to its fall to approximately 0.7 in controls.

CONCLUSION

Our findings suggest that ASA: 1) is only effective to treat the very transient TxB2-induced pulmonary vasoconstriction resulting in hydrostatic edema, and it is ineffective, even accentuates, the subsequent major pulmonary endothelial cell injury leading to alveolar flooding that is unrelated to TxB2; 2) has a transient protective effect on the TxB2-induced early bronchospasm; 3) has a biphasic behaviour on gas exchange, with a benefit which lasts only one hour and then results in a worse gas exchange; 4) has an immediate, stabilizing, persisting effect on R, contrasting with its transient effect on pulmonary hemodynamics and PaO2.

[TENS as an alternative analgesic treatment in dental settings]

The use of electrostimulation using low-intensity and very high frequency current, as an Electronic Analgesic (EDA) has aroused enormous interest during the last few years in Dentistry. Thanks to its use, good results have been obtained especially in the treatment of caries. This technique is suitable for several types of patients as those who have previously shown anaphylactic-anaphylactoid reactions to local anaesthetics, those who are afraid of needle, those who underwent to coronaric by-pass or have had myocardial infarction, those who employ omeophatic therapy and refuse traditional drugs and those who are in anticoagulant therapy, where it is preferable to avoid injection trauma. This technique offers a rapid disappearance of the effects and makes it possible to work in the same sitting on more than one quadrant of the mouth. The application of the technique instead shows relative or absolute contraindications in patients with pace-maker or with an history of alteration of rhythm, cerebral ictus or TIA.

Pneumocystis carinii pneumonia and acquired immunodeficiency syndrome: an atypical presentation with lung cavitations

The differential diagnosis of lung cavitations is very broad. We report a case of Pneumocystis carinii pneumonia (PCP) with lung cavitations on the chest X-ray in a patient with the acquired immunodeficiency syndrome (AIDS). We discuss the differential diagnosis of such an X-ray pattern and emphasize that multiple cavitations can be a roentgenographic presentation of PCP.

Pneumocystis carinii pneumonia and acquired immunodeficiency syndrome: an atypical presentation with lung cavitations

The differential diagnosis of lung cavitations is very broad. We report a case of Pneumocystis carinii pneumonia (PCP) with lung cavitations on the chest X-ray in a patient with the acquired immunodeficiency syndrome (AIDS). We discuss the differential diagnosis of such an X-ray pattern and emphasize that multiple cavitations can be a roentgenographic presentation of PCP.

The prominent role of thromboxane A2 formation on early pulmonary hypertension induced by oleic acid administration in sheep

The early increase of pulmonary artery pressure observed in different models of experimentally induced lung injury have been shown to be associated with the release of vasoconstrictive agents by activated platelets. The aim of this study was to evaluate the pattern of these metabolites, in particular TxA2, and the effects of the inhibition of their production by ASA on the modifications of pulmonary hemodynamics induced by oleic acid administration in sheep. Group I (8 sheep) was infused with oleic acid (0.09 ml/kg at 0.02 ml/min) while in group II (6 sheep) ASA (10 mg/kg i.v.) was administered 30 minutes before oleic acid infusion. In group I pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR) were significantly higher at the end of the infusion while cardiac output (CO) significantly decreased in comparison to baseline values. A marked increase in plasma TxB2 levels paralleled pulmonary hemodynamic changes. Also plasma 6 keto PGF levels increased after OA infusion. The early increase in PAP and PVR was significantly lower in group II (p less than 0.005) while CO did not undergo any significant change. ASA pretreatment significantly blunted the rise of TxB2 concentrations and prevented the elevation of 6 keto PGFa. These results indicate that early pulmonary hypertension in oleic acid induced injury is mainly related to TxA2 released from platelets and leukocytes and that pulmonary hemodynamic changes are significantly inhibited by ASA pretreatment.

Defibrotide in extracorporeal circulation on healthy rabbits

Defibrotide, a partially depolymerized DNA fraction obtained from mammalian lung, was found to have significant antithrombotic and fibrinolytic activities. On the basis of this evidence defibrotide could be of clinical value during hemoperfusive treatment. The present study was designed to evaluate the biological tolerance of this technique in a model of extracorporeal circulation, using an original Silastic apparatus, with defibrotide (0.83 mg/kg-1/min-1 after a 50 mg/kg-1 bolus injection) and heparin (0.66 IU/kg-1/min-1 after a 400 IU/kg-1 bolus injection) in ten rabbits (Group 1) and heparin only in ten others (Group 2, control group). In this study defibrotide produced a significantly lower pressure inside the circuit compared to the control group and gave a protective effect against those pathological changes which appeared during extracorporeal circulation and that may be considered omens of a state of shock. However the use of defibrotide in addition to heparin seemed to have a poor effect on platelet and leukocyte count alterations during application of this technique.

[Safety problems in the use of local anesthetics in the dental area]

In the last few years particular attention has been given to the adverse reaction to loco-regional anesthesia now widely used in dental practice. It has seemed therefore interesting to investigate the different types of adverse reactions, with particular attention to the anaphylactic-anaphylactoid ones. Although uncommon, these are interesting for the uncertain pathogenesis, the severity of the clinical picture and the complexity of the treatment. In order to find their adequate prevention, a particular approach to risk patients has been suggested to identify the eventual previous anaphylactic-anaphylactoid reactions and the drugs responsible for it. A procedure based on progressive skin test confirmed by a negative incremental challenge test has been worked out. Moreover the need has been felt for a drug surveillance program capable of collecting computerized data which allows real-time investigation of adverse reaction incidence, their typology and finally the effectiveness of prevention. This procedure should further ensure safety in loco-regional anesthesia in dental practice.

Establishment and Characterization of a New Human Melanoma Cell Line (HU 214) with a High Growth Potential and Stable Properties

A human melanoma cell line (HU 214) with high growth potential was established from a lymph node metastasis of a patient with advanced cutaneous melanoma. The cells of this line were able to grow in monolayer (according to the Rosenblum technique) and in agar (according to the Courtenay-Mills method), and formed tumors when injected in nude mice. The line has been maintained in culture for more than 47 passages. The cell cultures were periodically characterized (every 6-8 passages) by immunohistochemistry using a panel of monoclonal antibodies (MoAbs) including MoAbs against tumor-associated antigens (antimelanoma, antiglioma and anti-LLA), against vimentin, and against major histocompatibility antigens, and including also Ki 67, a MoAb which reacts with a nuclear antigen associated with cell proliferation. The results of this characterization indicate that we have established a human melanoma cell line with a stable antigenic phenotype during subculturing, poorly differentiated cells, and a high growth potential.