Safe practice guidance: a review for otorhinolaryngologists during COVID-19 pandemic and after reopen process

COVID-19’s rapid sweep across the world has caused an extraordinary disruption to the otorhinolaryngology (ORL) profession and its subspecialties including the rhinology section. The present pandemic forced our specialty practitioners to make quick clinical and practice management decisions. Staff safety must receive the highest prioritization along with strategies to provide the highest quality care. The purpose of the present manuscript is to provide a narrative review of the current knowledge and committee practices regarding ORL (including rhinology) professionals' safe practice during COVID-19 pandemic and after reopen process. The present review findings will allow the clinical practitioners to understand the factors involved in reducing the risk of transmission of COVID-19 in the ORL and rhinology settings, personal protective equipment (PPE) for different ORL and rhinology practices and criteria of practice in outpatient clinic (OPC), emergency operations and ORL surgeries. The emerging evidence based on COVID-19 is rapidly changing. Further updates may be needed to this review as new details or evidence emerge. ORL including rhinology doctors should consider the specific conditions of each individual place of work and comply with all applicable legislations.

The ESC ACCA EAPCI EORP acute coronary syndrome ST-elevation myocardial infarction registry

Aims 

The Acute Cardiac Care Association (ACCA)–European Association of Percutaneous Coronary Intervention (EAPCI) Registry on ST-elevation myocardial infarction (STEMI) of the EurObservational programme (EORP) of the European Society of Cardiology (ESC) registry aimed to determine the current state of the use of reperfusion therapy in ESC member and ESC affiliated countries and the adherence to ESC STEMI guidelines in patients with STEMI.

Methods and results 

Between 1 January 2015 and 31 March 2018, a total of 11 462 patients admitted with an initial diagnosis of STEMI according to the 2012 ESC STEMI guidelines were enrolled. Individual patient data were collected across 196 centres and 29 countries. Among the centres, there were 136 percutaneous coronary intervention centres and 91 with cardiac surgery on-site. The majority of centres (129/196) were part of a STEMI network. The main objective of this study was to describe the demographic, clinical, and angiographic characteristics of patients with STEMI. Other objectives include to assess management patterns and in particular the current use of reperfusion therapies and to evaluate how recommendations of most recent STEMI European guidelines regarding reperfusion therapies and adjunctive pharmacological and non-pharmacological treatments are adopted in clinical practice and how their application can impact on patients’ outcomes. Patients will be followed for 1 year after admission.

Conclusion 

The ESC ACCA-EAPCI EORP ACS STEMI registry is an international registry of care and outcomes of patients hospitalized with STEMI. It will provide insights into the contemporary patient profile, management patterns, and 1-year outcome of patients with STEMI.

Re-laparotomy after caesarean deliveries: risk factors and how to avoid?

The aim of this study was to explore the risk factors for and how to avoid re-laparotomy after caesarean delivery and to present the experience of a university tertiary care referral hospital. The study comprised of 2,000 caesarean deliveries, among which re-laparotomy was needed in 18 patients (0.9). The study found that 16 of the 18 cases that needed re-laparotomy had previous caesarean sections (CS) and 9/18 had placenta praevia. The main indication for the procedure was internal haemorrhage (haemoperitoneum) (12/18, 66.6%). Significant haemoperitoneum of > 2 litres was reported in six cases (33.3%). Maternal mortality occurred in 3/18 (16.6%) patients. The uterus was preserved in most patients (15 patients, 83.3%). A total of 12 patients needed re-suturing of the uterine incision; 10 patients had bilateral uterine artery ligation; and four patients had bilateral internal iliac artery ligation. Uterine compression B-Lynch suturing was needed in five patients with uterine atony. Six patients (33.3%) were admitted to the intensive care unit (ICU) and were discharged well. Re-laparotomy after caesarean delivery has many risk factors leading to postoperative haemorrhage. Early signs, such as tachycardia and hypotension must be closely monitored to allow early intervention and to avoid morbidity and mortality related to late re-laparotomy.

Subfertility treatment in women with systemic lupus erythematosus

This study comprised of 65 infertile patients with systemic lupus erythematosus (SLE). The aim was to study causes and different modalities used for the management of subfertile patients with SLE. All patients were diagnosed to have SLE according to the standard criteria of diagnosis. All patients were scheduled to expectant treatment, ovulation induction and timed intercourse, intrauterine insemination (IUI), intracytoplasmic sperm injection (ICSI). Anovulation was in 20 patients (20%), due to PCOS in 10 cases and due to other causes in three patients. A total of 28 patients (43.1%) needed laparoscopy for their work-up of infertility. Male factor for infertility was present in nine couples (16.7%). Ovulation induction and timed intercourse was adopted for a maximum 6 cycles and IUI for 3 cycles. In vitro fertilisation (IVF)/ICSI was needed in five cases using standard long agonist protocol. Four cases were complicated by significant ovarian hyperstimulation syndrome after conventional ovarian stimulation and cycles were cancelled. Pregnancy occurred in 20 women. Ovarian stimulation for ovulation induction and IVF seems to be safe and successful in well selected women with non-complicated SLE.

The Syk-kinase inhibitor R406 impairs platelet activation and monocyte tissue factor expression triggered by heparin-PF4 complex directed antibodies

BACKGROUND

Heparin-induced thrombocytopenia (HIT) is a rare but severe complication of heparin therapy in which immunoglobulin G (IgG) antibodies against the platelet factor 4-heparin complex activate platelets through the FcγRIIA receptor. Clustering of FcγRIIA initiates signaling cascades involving tyrosine kinases including the spleen tyrosine kinase (Syk). Moreover, besides the critical role of platelets, the expression of tissue factor (TF) by human monocytes triggered by HIT antibodies has been shown to contribute to the hypercoagulability and the thrombotic complications in HIT patients.

OBJECTIVES

We investigated the effect of R406, a small molecule inhibitor of Syk developed as a potential treatment of autoimmune diseases, allergic disorders and B-cell related hematological malignancies, on FcγRIIA-mediated platelet activation. To further assess the potential activity of Syk inhibitors in HIT treatment, the effect of R406 was also evaluated on HIT antibodies-induced expression of TF and procoagulant activity of monocytic cells.

RESULTS

We show that R406 is a potent inhibitor of platelet signaling and functions initiated by FcγRIIA cross-linking by specific antibodies or by sera from HIT patients. Syk inhibition efficiently prevents FcγRIIA-induced LAT phosphorylation and activation of phosphoinositide 3-kinase, Akt, phospholipase Cγ2 and p38 MAP-kinase. As a consequence, FcγRIIA-induced platelet aggregation, granule secretion and microparticles production are strongly inhibited by R406. Moreover, the Syk inhibitor efficiently impairs the expression of TF and the procoagulant activity of human monocytes triggered by HIT antibodies.

CONCLUSION

Syk inhibitors may be of therapeutic interest in the treatment of HIT by reducing HIT antibodies-mediated platelet activation and monocyte procoagulant activity.

Low-molecular weight heparin in patients with recurrent early miscarriages of unknown aetiology

The aim of this randomised prospective study was to assess the efficacy of early thromboprophylaxis with low-molecular weight heparin (LMWH) in women with a history of recurrent first trimester spontaneous abortion or miscarriages without identifiable causes vs no treatment. The study comprised of 340 women with unexplained spontaneous recurrent miscarriages. Patients in group A were prescribed LMWH (Enoxaparin sodium 0.2 ml, 20 mg, once daily subcutaneously) from the time of confirmation of fetal viability by ultrasonography until 34 weeks' gestation, and folic acid tablets 0.5 mg daily until 13 weeks' gestation. Patients in group B were given folic acid tablets 0.5 mg daily until 13 weeks' gestation. Termination of pregnancy was the primary outcome. There was a significant difference in the incidence of both early (4.1% vs 8.8%) and late miscarriages (1.1% vs 2.3%) in group A than in group B, respectively. There were no differences between both groups as regards the occurrence of pre-eclampsia, placental abruption, caesarean delivery, intra-partum bleeding or ecchymosis at operative wounds. There were no differences in most of the neonatal values between both groups. However, the mean birth weight was significantly higher in group A. LMWH seems to be a safe drug and effective in significantly reducing the incidence of recurrent miscarriages of unknown aetiology when given in the first trimester and continued throughout pregnancy.

Induction of ovulation in idiopathic premature ovarian failure: a randomized double-blind trial

In this prospective randomized study, women with idiopathic karyotypically normal premature ovarian failure (POF) were treated with gonadotrophin-releasing hormone (GnRH) agonist and gonadotrophins with and without the addition of corticosteroids in an attempt to restore ovarian function. The study comprised 58 women with idiopathic POF randomly allocated to either GnRH agonists (GnRHa) plus gonadotrophin therapy with the addition of corticosteroids (29 patients) or GnRHa plus gonadotrophin therapy with placebo (29 patients). Ovulation occurred in six cases (20.7%) in the dexamethasone group versus three cases (10.3%) in the placebo group. There were two singleton pregnancies in the dexamethasone group. There were no reported complications from the use of dexamethasone apart from a sense of sleepiness and fatigue. The combination of corticosteroids with pituitary suppression followed by ovarian stimulation with gonadotrophin appeared to be beneficial in restoring ovarian function in patients with idiopathic POF and normal karyotype.

Platelet aggregation induced by the C-terminal peptide of thrombospondin-1 requires the docking protein LAT but is largely independent of alphaIIb/beta3

Thrombospondin-1 (TSP1) is abundantly secreted during platelet activation and plays a role in irreversible platelet aggregation. A peptide derived from the C-terminal domain of TSP1, RFYVVMWK (RFY) can activate human platelets at least in part via its binding to integrin-associated protein. Although integrin-associated protein is known to physically interact with alphaIIb/beta3, we found that this major platelet integrin had only a partial implication in RFY-mediated platelet aggregation. Accordingly, RFY induced a significant Glanzmann type I thrombasthenic platelet aggregation. The alphaIIb/beta3-dependent part of platelet aggregation induced by RFY was mainly due to secreted ADP and thromboxane A2. In the absence of alphaIIb/beta3 and fibrinogen, RFY stimulated a rapid tyrosine phosphorylation of a set of proteins, including Syk, linker for activation of T cells (LAT) and phospholipase Cgamma2. This signaling pathway was critical for RFY-mediated platelet activation as revealed by the use of pharmacological inhibitors as well as LAT-deficient mouse platelets. Phosphoinositide 3-kinase activation was also required for RFY-mediated platelet aggregation. Our results unravel a new alphaIIb/beta3 and fibrinogen-independent mechanism for platelet aggregation in response to the active peptide from the C-terminal domain of TSP1.

Differential regulation of phosphoinositide metabolism by alphaVbeta3 and alphaVbeta5 integrins upon smooth muscle cell migration

Smooth muscle cell migration is a key step of atherosclerosis and angiogenesis. We demonstrate that alpha(V)beta(3) and alpha(V)beta(5) integrins synergistically regulate smooth muscle cell migration onto vitronectin. Using an original haptotactic cell migration assay, we measured a strong stimulation of phosphoinositide metabolism in migrating vascular smooth muscle cells. Phosphatidic acid production and phosphoinositide 3-kinase IA activation were triggered only upon alpha(V)beta(3) engagement. Blockade of alpha(V)beta(3) engagement or phospholipase C activity resulted in a strong inhibition of smooth muscle cell spreading on vitronectin. By contrast, blockade of alpha(V)beta(5) reinforced elongation and polarization of cell shape. Moreover, Pyk2-associated tyrosine kinase and phosphoinositide 4-kinase activities measured in Pyk2 immunoprecipitates were stimulated upon cell migration. Blockade of either alpha(V)beta(3) or alpha(V)beta(5) function, as well as inhibition of phospholipase C activity, decreased both Pyk2-associated activities. We demonstrated that the Pyk2-associated phosphoinositide 4-kinase corresponded to the beta isoform. Our data point to the metabolism of phosphoinositides as a regulatory pathway for the differential roles played by alpha(V)beta(3) and alpha(V)beta(5) upon cell migration and identify the Pyk2-associated phosphoinositide 4-kinase beta as a common target for both integrins.

Enterophilins, a new family of leucine zipper proteins bearing a b30.2 domain and associated with enterocyte differentiation

Enterocyte terminal differentiation occurs at the crypt-villus junction through the transcriptional activation of cell-specific genes, many of which code for proteins of the brush border membrane such as intestinal alkaline phosphatase, sucrase-isomaltase, or the microvillar structural protein villin. Several studies have shown that this sharp increase in specific mRNA levels is intimately associated with arrest of cell proliferation. We isolated several clones from a guinea pig intestine cDNA library. They encode new proteins characterized by an original structure associating a carboxyl-terminal B30.2/RFP-like domain and a long leucine zipper at the amino terminus. The first member of this novel gene family codes for a 65-kDa protein termed enterophilin-1, which is specifically expressed in enterocytes before their final differentiation. Enterophilin-1 is the most abundant in the small intestine but is still present in significant amounts in colonic enterocytes. In Caco-2 cells, a similar 65-kDa protein was recognized by a specific anti-enterophilin-1 antibody, and its expression was positively correlated with cell differentiation status. In addition, transfection of HT-29 cells with enterophilin-1 full-length cDNA slightly inhibited cell growth and promoted an increase in alkaline phosphatase activity. Taken together, these data identify enterophilins as a new family of proteins associated with enterocyte differentiation.

FcgammaRIIA requires a Gi-dependent pathway for an efficient stimulation of phosphoinositide 3-kinase, calcium mobilization, and platelet aggregation

FcgammaRIIA, the only Fcgamma receptor present in platelets, is involved in heparin-associated thrombocytopenia (HIT). Recently, adenosine diphosphate (ADP) has been shown to play a major role in platelet activation and aggregation induced by FcgammaRIIA cross-linking or by sera from HIT patients. Herein, we investigated the mechanism of action of ADP as a cofactor in FcgammaRIIA-dependent platelet activation, which is classically known to involve tyrosine kinases. We first got pharmacologic evidence that the ADP receptor coupled to Gi was required for HIT sera or FcgammaRIIA clustering-induced platelet secretion and aggregation. Interestingly, the signaling from this ADP receptor could be replaced by triggering another Gi-coupled receptor, the alpha(2A)-adrenergic receptor. ADP scavengers did not significantly affect the tyrosine phosphorylation cascade initiated by FcgammaRIIA cross-linking. Conversely, the Gi-dependent signaling pathway, initiated either by ADP or epinephrine, was required for FcgammaRIIA-mediated phospholipase C activation and calcium mobilization. Indeed, concomitant signaling from Gi and FcgammaRIIA itself was necessary for an efficient synthesis of phosphatidylinositol 3,4,5-trisphosphate, a second messenger playing a critical role in the process of phospholipase Cgamma2 activation. Altogether, our data demonstrate that converging signaling pathways from Gi and tyrosine kinases are required for platelet secretion and aggregation induced by FcgammaRIIA.

Phosphoinositide 3-kinase and integrin signalling are involved in activation of Bruton tyrosine kinase in thrombin-stimulated platelets

Bruton tyrosine kinase (Btk) plays a crucial role in the differentiation of B lymphocytes and belongs to the group of Tec kinases, which are characterised by the presence of a pleckstrin homology domain. Here we show that Btk is activated and undergoes tyrosine phosphorylation upon challenge of platelet thrombin receptor, these responses requiring engagement of alphaIIb/beta3 integrin and phosphoinositide 3-kinase activity. These data unravel a novel signalling pathway involving Btk downstream of an adhesive receptor via a complex regulation implicating the products of phosphoinositide 3-kinase, which might act to anchor Btk at the membrane.

Ectopic epididymal expression of guinea pig intestinal phospholipase B. Possible role in sperm maturation and activation by limited proteolytic digestion

Guinea pig intestinal phospholipase B is a calcium-independent phospholipase hydrolyzing sequentially the acyl ester bonds at sn-2 and sn-1 positions of glycerophospholipids, promoting the formation of sn-glycero-3-phosphocholine from phosphatidylcholine. This 140-kDa glycoprotein from the brush border membrane of differentiated enterocytes contributes to lipid digestion as an ectoenzyme. The cDNA coding for guinea pig phospholipase B was revealed to be the homologue of AdRab-B, an mRNA appearing in rabbit upon intestine development. The sequence predicts a polypeptide of 1463 amino acids displaying four homologous repeats, two of them containing the lipase consensus sequence GXSXG. A 5-kilobase transcript was particularly abundant in mature ileal and jejunal enterocytes but was also detected in epididymis, where phospholipase B displayed a higher molecular mass (170 kDa versus 140 kDa in intestine), with no obvious evidence for enzyme activity. Trypsin treatment of phospholipase B immunoprecipitated from epididymal membranes reduced its size to 140 kDa, coinciding with the appearance of a significant phospholipase A2 activity. The same results were obtained in COS cells transfected with phospholipase B cDNA. Since sn-glycero-3-phosphocholine present at high concentrations in seminal plasma mainly stems from epididymis, this suggests a possible role of phospholipase B in male reproduction. This novel localization also unravels a mechanism of phospholipase B activation by limited proteolysis involving either trypsin in the intestinal lumen or a trypsin-like endopeptidase in the male reproductive tract.

Integrin-dependent tyrosine phoshorylation and cytoskeletal translocation of Tec in thrombin-activated platelets

Using a specific polyclonal anti-Tec antibody, we have shown that Tec is expressed in human platelets. In addition, Tec was found to undergo tyrosine phosphorylation during platelet activation. The phosphorylation increased after 1 min and remained stable after 3 min of thrombin treatment. The tetrapeptide RGDS inhibited more than 90% of thrombin-induced tyrosine phosphorylation of Tec and blocked its translocation to the cytoskeleton. These results suggest that Tec participates in platelet signaling downstream of integrin activation.

G-protein beta gamma subunits mediate specific phosphorylation of the protein-tyrosine phosphatase SH-PTP1 induced by lysophosphatidic acid

SH-PTP1 is a protein-tyrosine phosphatase preferentially expressed in hematopoietic cells and bearing two SH2 (src homology-2) domains. In the human megakaryocytic cell line Dami, lysophosphatidic acid (LPA) promoted a rapid increase in SH-PTP1 phosphorylation on both serine and tyrosine residues. Only tyrosine phosphorylation was significantly inhibited by pertussis toxin and by the protein kinase C inhibitor GF109203X. Moreover, SH-PTP1 was phosphorylated upon challenge with other agonists acting via G-protein-coupled receptors such as alpha-thrombin, epinephrine, and ADP, whereas the closely related protein-tyrosine phosphatase SH-PTP2 failed to share such a regulation in Dami cells. We developed an in vitro assay that reproduced LPA-dependent phosphorylation of SH-PTP1 in a cell-free system. The fusion protein glutathione S-transferase-beta-adrenergic receptor kinase 1-(495-689) or the transducin subunit Galphat-GDP, which act as specific antagonists of Gbetagamma, inhibited SH-PTP1 phosphorylation. Moreover, purified transducin Gbetagamma subunits mimicked the effect of LPA. Finally, stable expression of beta-adrenergic receptor kinase 1-(495-689) in Dami cells resulted in the inhibition of SH-PTP1 as a specific target of protein kinases linked to G-protein-coupled receptors via Gbetagamma subunits.

Regional distribution of organochlorine insecticide residues in human milk from Egypt

The organochlorine insecticide residues in 60 human milk samples from 20 Egyptian governorates were analyzed by gas chromatography/electron capture and gas chromatography/mass spectrometry. The results showed that the main detected organochlorine insecticides were p,p'-DDE and lindane. Other HCH isomers, p,p'-DDT and endosulfan I residues were detected in some samples, but aldrin and endrin were not detected in most of the samples. The mean values for p,p'-DDE, lindane, endosulfan I and p,p'-DDT levels in the milk samples of the 20 governorates studied were 21.37 ppb, 8.42 ppb, 4.84 ppb and 2.93 ppb respectively, which are lower than the levels reported, a number of years ago, in most of the developed countries. Relatively higher levels of organochlorine insecticide residues were recorded in the samples from intensive agricultural activity regions.

Increase in receptor-like protein tyrosine phosphatase activity and expression level on density-dependent growth arrest of endothelial cells

Protein tyrosine phosphatase (PTPase) activity was examined in two cell lines: human umbilical vein endothelial (HUVE) cells, which display contact inhibition of cell growth, and A427 human adenocarcinoma cells, which have lost this ability. HUVE cells harvested at high density displayed a 10-fold increase in membrane-associated PTPase activity. A427 cells exhibited no such phenomenon. Moreover, modification of HUVE cell growth rate by a stimulating agent such as basic fibroblast growth factor or by blocking compounds such as thymidine or suramin resulted in no change in PTPase activity, suggesting that the observed increase in membrane-associated activity at confluency was specific for cell-cell-contact-directed growth arrest. The expression of various PTPase mRNAs was examined in HUVE and A427 cells. Of the receptor-like PTPases tested, two were exclusively expressed in HUVE cells (PTP gamma and HPTP beta). Only HPTP beta, which is structurally similar in its extracellular region to cell-adhesion receptors of the immunoglobulin superfamily, displayed a pattern of expression related to the increase in PTPase activity. Competitive PCR was used to quantify its expression during cell culture. A 12-fold increase in HPTP beta mRNA expression was detected and it parallelled the time course of PTPase activity. This observation strongly implicates receptor-like PTPases in density-dependent growth arrest.

Tyrosine phosphorylation of an SH2-containing protein tyrosine phosphatase is coupled to platelet thrombin receptor via a pertussis toxin-sensitive heterotrimeric G-protein

SH-PTP1 is a protein tyrosine phosphatase (PTP) predominantly expressed in haematopoietic cells and containing two src homology-2 (SH2) domains. Here we report that SH-PTP1 is phosphorylated on both serine and tyrosine residues in response to thrombin or phorbol myristate acetate (PMA), which increased by 60 and 40%, respectively, SH-PTP1 activity. Thrombin-induced phosphorylation of SH-PTP1 is an early signalling event (maximal within 10 s) involving neither integrin signalling, nor calcium, nor release of ADP or thromboxane A2. Moreover, in contrast with PMA, the effect of thrombin on the tyrosine phosphorylation of SH-PTP1 was hardly affected by GF109203X, a specific protein kinase C (PKC) inhibitor. Finally, phosphorylation of SH-PTP1 could be provoked in permeabilized platelets by thrombin or GTP gamma S. This was abolished by pertussis toxin, the specificity of this effect being verified with the megakaryocytic cell line Dami cell. Our data thus identify SH-PTP1 as an in vivo substrate of a putative protein tyrosine kinase linked to the thrombin receptor by a Gi protein. This might offer some clue to unravel the mechanism of thrombin not only in platelets but also in nucleated cells, where its mitogenic effect is known to involve pertussis toxin-sensitive G-proteins, tyrosine phosphorylation and the ras pathway.

Secretory phospholipase A2 generates the novel lipid mediator lysophosphatidic acid in membrane microvesicles shed from activated cells

Nonpancreatic secretory phospholipase A2 (sPLA2) displays proinflammatory properties; however, its physiological substrate is not identified. Although inactive toward intact cells, sPLA2 hydrolyzed phospholipids in membrane microvesicles shed from Ca(2+)-loaded erythrocytes as well as from platelets and from whole blood cells challenged with inflammatory stimuli. sPLA2 was stimulated upon degradation of sphingomyelin (SPH) and produced lysophosphatidic acid (LPA), which induced platelet aggregation. Finally, lysophospholipid-containing vesicles and sPLA2 were detected in inflammatory fluids in relative proportions identical to those used in vitro. We conclude that upon loss of phospholipid asymmetry, cell-derived microvesicles provide a preferential substrate for sPLA2. SPH hydrolysis, which is provoked by various cytokines, regulates sPLA2 activity, and the novel lipid mediator LPA can be generated by this pathway.

Renal toxicity of ifosfamide in pilot regimens of the intergroup rhabdomyosarcoma study for patients with gross residual tumor

PURPOSE

The purpose of this review is to characterize the nephrotoxicity noted in newly diagnosed patients under 21 years of age after treatment with ifosfamide-containing chemotherapy regimens and local irradiation for localized gross residual rhabdomyosarcoma or undifferentiated sarcoma.

PATIENTS AND METHODS

From 1987 to 1991, 194 previously untreated patients received vincristine and ifosfamide plus dactinomycin or etoposide for 1-2 years. Ifosfamide was given at 1.8 g/m2/day for 5 days with sodium mercaptoethane sulfonate, or 9 g/m2 of ifosfamide per course. The three-drug regimen was repeated every 3-4 weeks.

RESULTS

Twenty-eight patients (14%) developed renal toxicity: 19 had renal tubular dysfunction (RTD) characterized by low serum phosphate (< or = 3 mg/dl) or bicarbonate (< 20 or = mEq/L) levels, five had decreased glomerular function (DGF), and four had both RTD and DGF. When nine or more courses of ifosfamide (> 72 g/m2) were given, children < 3 years of age had a higher incidence of RTD than did children > or = 3 years of age (34% versus 6%; p < 0.001). A similar age difference was observed even when eight or fewer courses (< or = 72 g/m2) were given (p = 0.03). A matched case-control comparison showed that renal abnormalities at diagnosis, chiefly hydronephrosis, also increased the risk of renal tubular injury by ifosfamide by a factor of 13 (p < 0.001). Patients with DGF tended to be older than those with RTD, and all but one received > 72 g/m2 of ifosfamide.

CONCLUSIONS

Patients who are < 3 years of age who receive more than eight courses (> 72 g/m2) of ifosfamide and who have a preexisting renal abnormality have an increased risk of RTD and DGF. The renal function of patients being considered for ifosfamide treatment must be carefully monitored. Ifosfamide should be avoided in patients with renal abnormalities at diagnosis unless the potential benefit clearly exceeds the risk of further renal impairment.

Adolescent cancer survivors. Psychosocial and familial adaptation

Adolescent cancer survivors were compared with nondiseased control subjects on measures of adaptation, coping, body image, sexual adjustment, psychopathology, and family functioning. Cancer survivors reported no major difficulties in social competence, overall coping, and family communication. Although their school teachers reported no symptoms of psychopathology, the cancer survivors did report body image disturbances and adjustment difficulties. Further, the surviving adolescents were eager to present themselves favorably. Compared with nondiseased control families, families of survivors were characterized as somewhat inflexible. Implications for clinical practice include the careful monitoring of youth who have survived cancer as well as sensitivity to underlying concerns that the survivors and their families may avoid.

Neonatal rhabdomyosarcoma: the IRS experience

Neonatal rhabdomyosarcoma is rare, and the characteristics and optimal therapy for patients with this condition have not been well described. Of 3,217 eligible patients entered in the Intergroup Rhabdomyosarcoma Study (IRS), 14 were less than 30 days old at the time of diagnosis. Among these patients, male gender, Caucasian race, caudal tumors, and embryonal/botryoid and undifferentiated histology predominate. Although half the neonates survived, neither histology, tumor size, nor type of surgery were predictive of outcome. The presence of necrosis and small round cell configuration coincides with a poor prognosis, regardless of histological diagnosis. Neonatal rhabdomyosarcoma of caudal origin has a favorable prognosis.

Implication of a protein-tyrosine-phosphatase in human lung cancer

Protein tyrosyl phosphorylation plays an essential role in regulating cellular events such as proliferation, differentiation and oncogenesis. The recent characterization of the family of protein tyrosine phosphatases (PTPases) suggests that dephosphorylation might be a crucial event in these phenomena. One of the functions of PTPases is to reverse the effect of protein tyrosine kinases (PTKases), many of which are oncogenes, suggesting that they may act as tumor suppressors as described for HPTP gamma. In order to investigate the implication in lung cancer of HPTP beta, a receptor PTPase, we have developed a semi-quantitative method derived from primer-directed reverse transcription (RT) and subsequent polymerase chain reaction (PCR) with 32P-labelled nucleotide. We have demonstrated that the expression of HPTP beta mRNA was dramatically decreased in lung adenocarcinomas and lung malpighian carcinomas as compared to normal lung tissue. In addition, HPTP beta was not expressed in the pulmonar adenocarcinoma cell line A427, which proliferates in a deregulated way. These results suggest that the loss of expression of HPTP beta might play a role in neoplasic transformation and thus this molecule could act as a tumor suppressor factor.

Thrombin-induced redistribution of protein-tyrosine-phosphatases to the cytoskeletal complexes in human platelets

Human platelets provide an attractive model for studying the regulation of tyrosine phosphorylations and cell-cell adhesion. Major non-receptor tyrosine-kinases are suggested to be responsible for an increase in protein tyrosine phosphorylation following platelet stimulation. Agonist-induced platelet activation triggers also the reorganization of the cytoskeleton with association of multiple signalling proteins. To understand if protein-tyrosine-phosphatases (PTPs) were involved in platelet aggregation, we have investigated the subcellular distribution of these enzymes in resting and thrombin-stimulated platelets. A high level of PTP activity in human resting cells is distributed for 65% and 35%, respectively, in cytosolic and particular fractions. About 10% of this activity are redistributed to the cytoskeletal network during platelet activation. This translocation is dependent on actin polymerization as proved by the disappearance of this phenomenon in cells pretreated by cytochalasin D. Moreover, immunoblotting using anti-PTP polyclonal antibodies indicates that two PTPs, SH-PTP1 and p58 related to HPTP beta, translocate from membranes to Triton X-100 insoluble fractions after platelet activation. This translocation is correlated with the redistribution of several signalling proteins suggesting the possible regulation between these molecules and PTPs.

Translocation of an SH2-containing protein tyrosine phosphatase (SH-PTP1) to the cytoskeleton of thrombin-activated platelets

A significant protein tyrosine phosphatase (PTP) activity was found to be associated with the cytoskeleton of thrombin-stimulated platelets. Translocation of the enzyme became maximal within 1-2 min of thrombin stimulation and was suppressed by cytochalasin D or upon inhibition of aggregation. Immunoblotting as well as immunoprecipitation revealed that a PTP with two SH2 domains (SH-PTP1) displayed the same behaviour, translocation to the cytoskeleton showing the same time course as that observed for pp60c-src. We conclude that SH-PTP1 might represent a critical enzyme in the complex interplay between the various proteins regulating protein tyrosine phosphorylation in the cytoskeletal matrix.

Chemotherapy for acute lymphocytic leukemia: cognitive and academic sequelae

Iatrogenic cognitive impairments have been reported for survivors of childhood leukemia after prophylactic central nervous system therapy with craniospinal radiation. To determine whether chemotherapy alone might be a source of central nervous system damage, we assessed in a cross-sectional design the cognitive and academic functioning of 48 children with acute lymphocytic leukemia who were at various stages in their treatment or who had completed treatment. The off-therapy patients who had completed a 3-year course of chemotherapy were more impaired in tasks of higher-order cognitive functioning than were those children whose leukemia had been newly diagnosed and those children whose diagnoses had been 1 year earlier. Off-therapy patients also had concomitant diagnosable learning disabilities in mathematics. We recommend appropriate liaison and special education placements, as well as continued evaluation of cognitive and leaning functioning of children treated for moderate-risk acute lymphocytic leukemia who receive chemotherapy alone.

Cognitive status of children treated with central nervous system prophylactic chemotherapy for acute lymphocytic leukemia

Treatment-related cognitive impairments have been reported for survivors of childhood leukemia following prophylactic central nervous system (CNS) treatment with craniospinal radiation. We examined the neurocognitive status of 46 children with acute lymphocytic leukemia (ALL) to assess the impact of a regimen consisting of systemic chemotherapy and prophylactic CNS chemotherapy. By comparing three groups of ALL children (i.e., patients whose diagnosis was recent, patients 1 year postdiagnosis currently receiving CNS prophylactic chemotherapy, and off-therapy patients who had been treated with chemotherapy for 3 years) and their healthy siblings on measures of sequential and simultaneous processing, we were able to examine the effects of CNS prophylactic and systemic chemotherapy at various points during treatment. Results indicate that the children who had received a 3-year course of chemotherapy (off-therapy patients) were more impaired on tasks involving right-hemisphere simultaneous processing than were sibling controls or ALL children whose diagnosis was recent and whose treatment had just begun. Age at diagnosis did not interact with the effects of chemotherapy. These findings support the need for continued evaluation of cognitive functioning in ALL, children receiving CNS prophylactic chemotherapy to identify potential harmful neurocognitive sequelae of treatment.

A study of toxicity and comparative therapeutic efficacy of vindesine-prednisone vs. vincristine-prednisone in children with acute lymphoblastic leukemia in relapse. A Pediatric Oncology Group study

Vindesine (des-acetyl Vinblastine) is a synthetic derivative of vinblastine, and was produced with the hope that it would have less neurotoxicity and hematopoietic toxicity than other vinca alkaloids. Phase I and II studies also demonstrated significant activity in lymphoid malignancies, especially Acute Lymphoblastic Leukemia (ALL). The present study was designed to compare therapeutic effectiveness of twice weekly vindesine (2 mg/M2/dose) plus Prednisone (60 mg/M2/dose) (Treatment 1) to weekly Vincristine (2 mg/M2/dose) plus Prednisone (60 mg/M2/day) (Treatment 2). All patients were less than 21 years of age, and had documented bone marrow relapse (blast count > 25%). In 39 patients presumed sensitive to vincristine, there were 11 complete responses out of 20 patients (55%) randomized to receive vindesine/prednisone and 7 complete responses out of 19 patients (37%) treated with Vincristine/Prednisone. In 37 patients resistant to vincristine, there were 7 complete responses (19%). Vindesine was more toxic than Vincristine. Major toxicities of vindesine included paraesthesias, peripheral neuropathy and ileus. Vindesine hematological toxicity appeared greater, but such toxicity is hard to assess in patients with bone marrow disease. In this study, vindesine and vincristine had similar efficacy, but vindesine use was associated with more toxicity.

Expression of a truncated protein-tyrosine phosphatase mRNA in human lung

Protein-tyrosine phosphatases (PTPases) are becoming an important family of enzymes that might regulate key events in cell growth and transformation. While isolating a new member of this family via amplification of human lung cDNA by the polymerase chain reaction, we found a clone identical to but truncated at the 3'-end of the coding region of human PTPase beta (HPTP beta) mRNA. This difference in sequence is situated in the most conserved part of the catalytic domain of the enzyme. The expression level of the truncated form of HPTP beta mRNA in human lung was lower than its normal form.

Extended haplotypes and linkage disequilibrium between 11 markers at the APOA1-C3-A4 gene cluster on chromosome 11

One hundred fifty-four unrelated French Caucasian subjects were typed for 11 RFLPs at or near the APOA1-C3-A4 gene cluster on the long arm of chromosome 11. All subjects belonged to families having lived in the Toulouse area (in the southwest of France) for over three generations. Allele frequencies for each RFLP were in agreement with previous studies in Caucasian populations for the APOA1/SstI marker. Pairwise linkage disequilibrium was determined. Among the 55 pairs studied, 30 are newly reported. Only three significant nonrandom associations were found: APOA1/MspI-3'APOC3/SstI, APOA1/MspI-3'APOA4/XbaI, and APOA4/DraI-APOA4/XbaI. Extended 11-marker haplotypes were constructed. Haplotype frequencies were estimated by the maximum-likelihood procedure and compared to expected frequencies calculated under the assumption of equilibrium. Among the 37 estimated haplotypes, seven containing at least four nonrandomly associated alleles showed markedly increased frequencies. These results, obtained in a geographically homogeneous population, confirm the existence of disequilibrium in the apolipoprotein cluster, but to a lower extent than previously reported in Caucasian populations, which were geographically more heterogeneous.

A comparison of induction and maintenance therapy for acute nonlymphocytic leukemia in childhood: results of a Pediatric Oncology Group study

Two hundred fifty-six children with previously untreated acute nonlymphocytic leukemia (ANLL) were evaluated on a Pediatric Oncology Group (POG) phase III randomized trial of both induction and continuation chemotherapies. Induction therapy compared vincristine, cytarabine, and dexamethasone (VADx) with daunorubicin, cytarabine, and thioguanine (DAT). The complete remission (CR) rate using DAT was superior (82% v 61%, P = .02). Postremission therapy consisted of either "standard" two-cycle therapy or a more intensive four-cycle regimen given for 2 years. Overall, there was no difference in outcome for patients randomized to either continuation regimen. The overall complete continuous remission rate (CCR) for the "best" induction/continuation therapy combination at 2 years was .50 (SE = .06), at 3 years was .35 (.04), and at 4 years was .34 (.05). Analysis of selected clinical and laboratory parameters demonstrated differences in induction responses favoring DAT induction but did not impact eventual disease-free survival. There were two subgroups of patients who responded better to four-cycle continuation therapy. These were patients with French-American-British (FAB) M1/M2 (2-year CCR was .20 v .44, P = .01) and patients older than 10 years at diagnosis (.32 v .62, P = .004).

High-dose cyclophosphamide-high-dose methotrexate with coordinated intrathecal therapy for advanced nonlymphoblastic lymphoma of childhood: results of a Pediatric Oncology Group study

The Pediatric Oncology Group (POG) investigated a high-dose cyclophosphamide (CPM) high-dose methotrexate (MTX) regimen to determine therapeutic efficacy in confirmed advanced nonlymphoblastic non-Hodgkin's lymphoma (NHL) (stages III and IV) and B-cell acute lymphatic leukemia (B-ALL) in children. Another goal was to determine the comparative effectiveness of shortened maintenance treatment (2 versus 6 courses) in the study population. Systemic induction therapy included vincristine, prednisone, cyclophosphamide, and intermediate-dose MTX with leucovorin rescue. Superimposed intrathecal (IT) therapy included cytosine arabinoside for 2 successive days followed on day 3 by MTX. Intrathecal MTX was given 3 times during induction. At the end of induction, 2 days of triple (hydrocortisone, MTX, and cytosine arabinoside) therapy were given intrathecally (TIT). All patients then received a consolidation course of 4 doses of TIT, 2 doses of cyclophosphamide, and 4 more courses of vincristine and MTX with leucovorin rescue. Patients were then randomized to receive either 2 or 6 cycles of vincristine plus MTX with leucovorin rescue. The TIT was given with each cycle. Complete response rates by histology and Murphy stage (1) were as follows: undifferentiated lymphoma (DUL) stage III, 84/105 (80%): stage IV, 5/12 (42%); and other NHL [primarily large cell lymphoma (LCL)] stage III, 21/28 (75%); stage IV, 2/3 (67%). Event-free survival (EFS) at greater than 2 years was similar for patients with DUL and LCL, i.e., 65 and 61%, respectively. No significant difference in outcome was noted between patient groups receiving 2 or 6 maintenance treatments (p = .76). Treatment was notable for its modest toxicity following the early change to single-dose CPM therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Detection by denaturing gradient gel electrophoresis of a new polymorphism in the apolipoprotein B gene

The apolipoprotein B gene is subject to mutations that may be important in coronary heart diseases. We have used polymerase chain reaction and denaturing gradient gel electrophoresis to characterize a single nucleotide substitution in the apolipoprotein B gene. This mutation affects amino acid 4311 of the protein and converts asparagine to serine. It was found in 24% of the 81 unrelated individuals analyzed. Moreover, another mutation was detected by sequencing in a single individual.

Secondary surgical procedures to evaluate primary tumor status in patients with chemotherapy-responsive stage III and IV sarcomas: a report from the Intergroup Rhabdomyosarcoma Study

Fifty children with clinical group III (localized, but unresected) or clinical group IV (disseminated) soft tissue sarcomas were entered in a trial to determine if the addition of etoposide and cisplatin to standard chemotherapy regimens and irradiation (4,000 cGy) would be tolerated by pediatric patients. Responding patients had a secondary surgical procedure performed after approximately 20 weeks of therapy for the purpose of establishing histological response, determining its extent, and removing residual tumor tissue, when feasible. Such procedures were performed in 29 of 50 (58%) of these patients, ie, 20 of 31 (65%) of those in group III, and nine of 19 (47%) of those in group IV. Surgical procedures consisted of exploration of the site and biopsy (only) in 16 patients; grossly complete tumor excision in nine; and subtotal tumor excision in four. In nine patients (six in group III, three in group IV) apparent total excision of a previously unresected primary tumor mass was accomplished at second surgery. One distant but no local relapse has occurred in this group, and eight of nine have survived (five of six with identified tumor in the specimen) for a duration of 232 to 348 weeks (six greater than 260 wks), suggesting that among patients with primary tumors in selected sites, with either stage III or stage IV disease, excision of residual masses following intensive chemotherapy/radiotherapy regimens may favorably influence outcome. Local relapse subsequently occurred in seven of 18 patients in whom tumor tissue could not be identified in biopsy specimens or in excised masses taken from the primary site at second surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Philadelphia chromosome positive childhood acute lymphoblastic leukemia: clinical and cytogenetic characteristics and treatment outcome. A Pediatric Oncology Group study

Among 3,638 children with acute lymphoblastic leukemia (ALL) entered on Pediatric Oncology Group (POG) protocols between June 1981 and April 1989, successful cytogenetic studies were available for 2,519, 58 (2.3%) of which had the Philadelphia (Ph) chromosome detected. Features associated with the presence of the Ph chromosome were high leukocyte count (median, 33 x 10(9)/L), older age median, 9.6 years), a higher proportion of French-American-British L2 morphology, and a lower frequency of mediastinal mass. Immunologic marker studies at diagnosis in 56 Ph+ cases identified early pre-B ALL in 42 cases (75%), pre-B-cell in 9 (16%), and T-cell in 5 (9%). This distribution is similar to that found in Ph+ ALL. Intensive multiagent chemotherapy induced complete remissions in only 78% of eligible Ph+ patients compared with 96% of those without an identified Ph chromosome (P less than .001). Of 44 eligible Ph+ patients treated on POG frontline protocols for children with non-T, non-B-cell ALL, 27 have failed therapy, compared with 520 of 1,892 without an identified Ph chromosome (logrank P less than .001). Ph+ ALL is an aggressive form of acute leukemia that frequently presents in older children with a high leukocyte count, FAB L2 morphology, and a pseudodiploid karyotype, and becomes multidrug-resistant early. Thus, Ph+ cases require early identification to permit treatment with intensive induction regimens and experimental approaches such as bone marrow transplantation.