2-Deoxy-d-Glucose and Its Analogs: From Diagnostic to Therapeutic Agents.

The ability of 2-deoxy-d-glucose (2-DG) to interfere with d-glucose metabolism demonstrates that nutrient and energy deprivation is an efficient tool to suppress cancer cell growth and survival. Acting as a d-glucose mimic, 2-DG inhibits glycolysis due to formation and intracellular accumulation of 2-deoxy-d-glucose-6-phosphate (2-DG6P), inhibiting the function of hexokinase and glucose-6-phosphate isomerase, and inducing cell death. In addition to glycolysis inhibition, other molecular processes are also affected by 2-DG. Attempts to improve 2-DG's drug-like properties, its role as a potential adjuvant for other chemotherapeutics, and novel 2-DG analogs as promising new anticancer agents are discussed in this review.

Australian consensus guidelines for the safe handling of monoclonal antibodies for cancer treatment by healthcare personnel.

These consensus guidelines provide recommendations for the safe handling of monoclonal antibodies. Definitive recommendations are given for the minimum safe handling requirements to protect healthcare personnel. The seven recommendations cover: (i) appropriate determinants for evaluating occupational exposure risk; (ii) occupational risk level compared with other hazardous and non-hazardous drugs; (iii) stratification of risk based on healthcare personnel factors; (iv) waste products; (v) interventions and safeguards; (vi) operational and clinical factors and (vii) handling recommendations. The seventh recommendation includes a risk assessment model and flow chart for institutions to consider and evaluate clinical and operational factors unique to individual healthcare services. These guidelines specifically evaluated monoclonal antibodies used in the Australian cancer clinical practice setting; however, the principles may be applicable to monoclonal antibodies used in non-cancer settings. The guidelines are only applicable to parenterally administered agents.

Parotid gland tumors in children - pre- and postoperative diagnostic difficulties.

Major salivary gland tumors are very rare in the developmental period. Confirming tumor changes in the salivary gland requires precise diagnostic imaging involving an ultrasonography scan, computed tomography and magnetic resonance. Needle aspiration biopsy (NAB) of the tumor is of high importance. Excision is the basic treatment method in cases of parotid gland tumor. The statistical data concerning tumors favor less invasive methods, which seems logical in the population of children. The surgical methods used in tumor treatment feature extracapsular excision of tumor, partial parotidectomy and total parotidectomy, sometimes followed by lymphatic node surgery. The clinical cases presented in the paper show difficulties with pre- and postoperative histopathological diagnosis in major salivary gland tumors in children. A core biopsy of the tumor may improve the accuracy of preoperative diagnosis but it does not exclude the possibility of misdiagnosis.

Population pharmacokinetics of mavacoxib in osteoarthritic dogs.

Mavacoxib (Trocoxil™) is an oral long-acting COX-2 inhibitor approved for the treatment of osteoarthritis in dogs. Two field trials were conducted in client-owned dogs suffering from osteoarthritis, with dosages of 4 mg/kg body weight (BW) (Study 1) or 2 mg/kg BW (Study 2). Mavacoxib plasma concentrations were determined from trough blood samples and from blood samples collected at 4-10 months after the last dose. A one-compartment linear model was fitted to the concentration data (1317 concentration records from 286 patients), and parameters for oral clearance (Cl/F), apparent volume of distribution (V(d) /F) and their between-subject variabilities (BSV) were estimated. Covariates were included in the model based on the outcomes of stepwise regression procedures. In the final model, the typical value of Cl/F was a function of BW, age and breed. German shepherds and Labrador retrievers were found to have 31% higher values of Cl/F than patients from different breeds with similar ages and BWs. The typical value of V(d) /F was found to be dependent only on BW. The two field studies appeared to differ similarly with respect to Cl/F and V(d) /F. The explanation for this difference is not known, but the difference was accounted for in the final model as a 23.9% lower bioavailability in Study 2. Mavacoxib exhibited relatively broad BSV in Cl/F and V(d) /F, with coefficients of variation of 47% and 19%, respectively. The typical value for mavacoxib's terminal elimination plasma half-life (t(1/2) ) was 44 days, but a minority of patients (approximately 5%) had empirical Bayes estimates of t(1/2) exceeding 80 days. Simulations with the model indicated that the majority of patients treated with mavacoxib 2 mg/kg will maintain trough plasma mavacoxib concentrations associated with efficacy. Results of the population pharmacokinetic analysis helped to reduce the dose from 4 to 2 mg/kg and thus increased the therapeutic index for this molecule.

Impact of COVID-19 on cancer service delivery: a follow-up international survey of oncology clinicians.

BACKGROUND: The COVID-19 pandemic has had a vast impact on cancer service delivery around the world. Previously reported results from our international survey of oncology clinicians, conducted through March-April 2020, found that clinicians reported altering management in both the curative and palliative settings and not in proportion to the COVID-19 case burden in their region of practice. This follow-up survey, conducted from 27th September to 7th November 2020, aimed to explore how attitudes and practices evolved over the 2020 pandemic period. PARTICIPANTS AND METHODS: Participants were medical, radiation and surgical oncologist and trainees. Surveys were distributed electronically via ESMO and other collaborating professional societies. Participants were asked to compare their practice prior to the pandemic to both the period of March-April 2020, referred to as the 'early' period, and the current survey period, referred to as the 'later' period. RESULTS: One hundred and seventy-two oncology clinicians completed the survey. The majority of respondents were medical oncologists (n = 136, 79%) and many were from Europe (n = 82, 48%). In the 'early' period, 88% (n = 133) of clinicians reported altering their practice compared to 63% (n = 96) in the 'later' period. Compared to prior to the pandemic, clinicians reported fewer new patient presentations in the 'early' period and a trend towards more patients presenting with advanced disease in the 'later' period. CONCLUSIONS: Results indicate a swing back towards pre-COVID-19 practices despite an increase in the rate of cumulative COVID-19 cases across 2020. The impact of these changes on cancer associated morbidity and mortality remains to be measured over the months and years to come.

Synthesis of thylakoid membrane proteins by chloroplasts isolated from spinach. Cytochrome b559 and P700-chlorophyll a-protein.

Intact chloroplasts, purified from spinach leaves by sedimentation in density gradients of colloidal silica, incorporate labeled amino acids into at least 16 different polypeptides of the thylakoid membranes, using light as the only source of energy. The thylakoid products of chloroplast translation were visualized by subjecting membranes purified from chloroplasts labeled with [35S]methionine to electrophoresis in high-resolution, SDS-containing acrylamide gradient slab gels and autoradiography. The apparent mol wt of the labeled products ranged from less than 10,000 to greater than 70,000. One of the labeled products is the apoprotein of the P700-chlorophyll a-protein (CPI). The CPI apoprotein is assembled into a pigment-protein complex which is electrophoretically indistinguishable from the native CPI complex. Isolated spinach chloroplasts also incorporate [3H]leucine and [35S]methionine into cytochrome b559. The radioactive label remains with the cytochrome through all stages of purification: extraction of the thylakoid membranes with Triton X-100 and urea, adsorption of impurities on DEAE cellulose, two cycles of electrophoresis in Triton-containing polyacrylamide gels and electrophoresis in SDS-containing gradient gels. Cytochrome b559 becomes labeled with both [3H]leucine and [35S]methionine and accounts for somewhat less than 1% of the total isotopic incorporation into thylakoid protein. The lipoprotein appears to be fully assembled during the time-course of our labeling experiments.

Analysis of suborganellar fractions from spinach and pea chloroplasts for calmodulin-binding proteins.

Purified chloroplasts from spinach and pea leaves were subfractionated into envelope, thylakoid, and stroma fractions and were analyzed for calmodulin-binding proteins using a 125I-calmodulin gel overlay assay. Calmodulin binding was primarily associated with a major polypeptide (Mr 33,000) in the envelope membrane fraction. In contrast, major calmodulin-binding proteins were not detected in the thylakoid or stroma fractions. Our results provide the first evidence of calmodulin-binding proteins in the chloroplast envelope, and raise the possibility that calmodulin may contribute to the regulation of chloroplast function through its interaction with calmodulin-binding proteins in the chloroplast envelope. In addition, our results combined with those of other investigators support the proposal that subcellular organelles may be a primary site of calmodulin action.

Pharmacokinetics of intravenous ceftiofur sodium and concentration in body fluids of foals.

The objectives of this study were to determine pharmacokinetics of intravenous (i.v.) ceftiofur in foals, to compare ultra-high performance liquid chromatography tandem mass spectometry (UPLC-MS/MS) and microbiologic assay for the measurement of ceftiofur concentrations, and to determine the minimum inhibitory concentration (MIC) of ceftiofur against common equine bacterial pathogens. In a cross-over design, ceftiofur sodium was administered i.v. to six foals (1-2 days-of-age and 4-5 weeks-of-age) at dosages of 5 and 10 mg/kg. Subsequently, five doses of ceftiofur were administered i.v. to six additional foals between 1 and 5 days of age at a dose of 5 mg/kg q 12 h. Concentrations of desfuroylceftiofur acetamide (DCA), the acetamide derivative of ceftiofur and desfuroylceftiofur-related metabolites were measured in plasma, synovial fluid, urine, and CSF by use of UPLC-MS/MS. A microbiologic assay was used to measure ceftiofur activity for a subset of plasma samples. Following i.v. administration of ceftiofur at a dose of 5 mg/kg to 1-2 day-old foals, DCA had a t(1/2) of 7.8 +/- 0.1 h, a body clearance of 74.4 +/- 8.4 mL/h/kg, and an apparent volume of distribution of 0.83 +/- 0.09 L/kg. After multiple i.v. doses at 5 mg/kg, DCA concentrations in CSF were significantly lower than concurrent plasma concentrations. Ceftiofur activity using a microbiologic assay significantly underestimated plasma concentrations of DCA. The MIC of ceftiofur required to inhibit growth of 90% of isolates of Escherichia coli, Pasteurella spp, Klebsiella spp, and beta-hemolytic streptococci was <0.5 microg/mL. Intravenous administration of ceftiofur sodium at the rate of 5 mg/kg every 12 h would provide sufficient coverage for the treatment of susceptible bacterial isolates.

Biosynthesis of calmodulin in normal and virus-transformed chicken embryo fibroblasts.

We report here that the higher levels of calmodulin in transformed chicken embryo fibroblasts are due to an increase in the rate of synthesis of calmodulin that results from an increased amount of calmodulin-specific mRNA in transformed cells. Transformation of several types of eucaryotic cells by oncogenic viruses results in a two- to threefold increase in the intracellular levels of calmodulin. We used the normal chicken embryo fibroblast and its Rous sarcoma virus-transformed counterpart to examine the biosynthesis of calmodulin. We show that the higher levels of calmodulin found in transformed fibroblasts appear to be the consequence of a selective increase in the rate of synthesis of calmodulin above that of total soluble or total cellular protein. A significant difference in the rate of degradation of calmodulin or total protein between transformed and normal cells was not detected. We also examined the mechanism of the increased synthesis rate of calmodulin and show that the levels of calmodulin mRNA are increased in transformed fibroblasts as measured by both translational activity and hybridization to a calmodulin cDNA probe. It is suggested by these data that the higher levels of calmodulin in transformed cells may result from a specific increase in the rate of either calmodulin gene transcription or mRNA processing.

Origin and phylogenetic distribution of Alu DNA repeats: irreversible events in the evolution of primates.

Over the past 60 million years, or so, approximately one million copies of Alu DNA repeats have accumulated in the genome of primates, in what appears to be an ongoing process. We determined the phylogenetic distribution of specific Alu (and other) DNA repeats in the genome of several primates: human, chimpanzee, gorilla, orangutan, baboon, rhesus, and macaque. At the population level studied, the majority of the repeats was found to be fixed in the primate species. Our data suggest that new Alu elements arise in unique, irreversible events, in a mechanism that seems to preclude precise excision and loss. The same insertions did not arise independently in two species. Once inserted and genetically fixed, the DNA elements are retained in all descendant lineages. The irreversible expansion of Alu s introduces a vector of time into the evolutionary process, and provides realistic (rather than statistical) answers to questions on phylogenies. In contrast to point mutations, the present distribution of individual Alu s is congruent with just one phylogeny. We submit that only irreversible and taxonomically relevant events are at the molecular basis of evolution. Most point mutations do not belong to this category.

Alu-mediated phylogenetic novelties in gene regulation and development.

Differential gene expression lies at the heart of biology and is responsible for all developmental processes, including the growth and differentiation of cells. Perhaps even speciation could be defined as a change in differential gene expression over evolutionary time. The present work is a phylogenetic study of four Alu elements known to have gene regulatory functions in the human. The four elements have been shown to regulate the parathyroid hormone (PTH) gene via a negative calcium-response element, the hematopoietic cell-specific FcepsilonRI-gamma receptor gene via a cis-acting positive/negative regulatory element, the CNS-specific nicotinic acetylcholine receptor alpha3 gene via a cis-acting positive/negative control element, and the T-cell-specific CD8alpha gene via a complex transcriptional regulator. The four Alu elements that impact differential gene expression were found to be differentially distributed among seven primate species (human, chimpanzee, gorilla, orangutan, baboon, rhesus, and macaque) in a way that is congruent with an accepted phylogeny of these species. The results establish a link between gene regulation and the divergence of primates. This evolutionary variation in gene regulation also suggests a novel experimental system to study the very complex transcriptional regulation of gene expression, by studying side-by-side the regulation of the same gene from two primate species that differ in the cis-acting regulatory elements of the gene.

Human genetic disorders, a phylogenetic perspective.

When viewed from the perspective of time, human genetic disorders give new insights into their etiology and evolution. Here, we have correlated a specific set of Alu repetitive DNA elements, known to be the basis of certain genetic defects, with their phylogenetic roots in primate evolution. From a differential distribution of Alu repeats among primate species, we identify the phylogenetic roots of three human genetic diseases involving the LPL, ApoB, and HPRT genes. The different phylogenetic age of these genetic disorders could explain the different susceptibility of various primate species to genetic diseases. Our results show that LPL deficiency is the oldest and should affect humans, apes, and monkeys. ApoB deficiency should affect humans and great apes, while a disorder in the HPRT gene (leading to the Lesch-Nyhan syndrome) is unique to human, chimpanzee, and gorilla. Similar results can be obtained for cancer. We submit that de novo transpositions of Alu elements, and saltatory appearances of Alu-mediated genetic disorders, represent singularities, places where behavior changes suddenly. Alus' propensity to spread, not only increased the regulatory and developmental complexity of the primate genome, it also increased its instability and susceptibility to genetic defects and cancer. The dynamic spread not only provided markers of primate phylogeny, it must have actively shaped the course of that phylogeny.

The chimpanzee alpha-fetoprotein-encoding gene shows structural similarity to that of gorilla but distinct differences from that of human.

The chimpanzee (Pan troglodytes) alpha-fetoprotein (AFP)-encoding gene (AFP) spans 18,867 bp from the transcription start point to the polyadenylation site, and the nucleotide (nt) sequence reveals that the gene is composed of 15 exons, which are symmetrically placed within three domains of AFP. In addition, we report 3121 bp of 5'-flanking sequence and 4886 bp of 3'-flanking sequence. The entire 26,874 bp of contiguous DNA reported here was determined from three overlapping lambda phage clones. The deduced polypeptide chain is composed of a 19-amino-acid (aa) putative leader peptide, followed by 590 aa of the mature protein. The sequence of chimpanzee AFP was compared with those of the previously published human AFP [Gibbs et al., Biochemistry 26 (1987) 1332-1343] and gorilla AFP [Ryan et al., Genomics 9 (1991) 60-72]. At the aa level, the human AFP differs from the chimpanzee at 6 aa positions and from the gorilla at 4 aa positions; the chimpanzee and gorilla differ at 8 aa positions. There are four types of repetitive sequence elements (X, Alu, Xba and Kpn) in the introns and flanking regions of chimpanzee AFP, and they are located in orthologous positions in the human and gorilla AFP. However, one specific Alu and one Xba repeat in introns 4 and 7, respectively, found in human AFP, are absent from orthologous positions in chimpanzee and gorilla AFP. These two repeats represent human-specific novelties that arose from recent DNA transpositions in primate phylogeny.

Cardiovascular complications of ECT in depressed patients with cardiac disease.

OBJECTIVE: This study was conducted to determine the safety of electroconvulsive therapy (ECT) for depressed patients with serious cardiac disease. METHOD: The rate of complications in 40 patients with major depressive disorder and left ventricular impairment, ventricular arrhythmias, and/or conduction delay who received ECT was compared to the rate of complications in a matched comparison group of 40 depressed patients without cardiac disease who also received ECT. In addition, 21 of the patients with cardiac illness had received one or more inpatient trials of tricyclic antidepressants before receiving ECT, thereby permitting a comparison of cardiovascular complications of medication and ECT in the same patients. RESULTS: The patients with cardiac disease had a significantly higher rate of cardiac complications during ECT than did the comparison group without cardiac disease. The type of preexisting cardiac abnormality strongly predicted the type of cardiac complication that occurred during ECT. However, most of the complications were transitory and did not prevent the completion of ECT. Of the 21 patients with cardiac disease who had received tricyclic trials before ECT, 11 had been forced to discontinue drug treatment because of substantial cardiovascular side effects. In comparison, 38 of the 40 cardiac patients completed the course of ECT. CONCLUSIONS: With close monitoring for the development of arrhythmia and ischemic episodes, ECT can be given with relative safety to patients with severe cardiovascular disease.

The influence of pH on antioxidant properties and the mechanism of antioxidant action of hydroxyflavones.

The effect of the pH on antioxidant properties of a series of hydroxyflavones was investigated. The pKa of the individual hydroxyl moieties in the hydroxyflavones was compared to computer-calculated deprotonation energies. This resulted in a quantitative structure activity relationship (QSAR), which enables the estimation of pKa values of individual hydroxyl moieties, also in hydroxyflavones for which these pKa values are not available. Comparison of the pKa values to the pH-dependent antioxidant profiles, determined by the TEAC assay, reveals that for various hydroxyflavones the pH-dependent behavior is related to hydroxyl moiety deprotonation, resulting in an increase of the antioxidant potential upon formation of the deprotonated forms. Comparison of these experimental results to computer calculated O-H bond dissociation energies (BDE) and ionization potentials (IP) of the nondeprotonated and the deprotonated forms of the various hydroxyflavones indicates that especially the parameter reflecting the ease of electron donation, i.e., the IP, and not the BDE, is greatly influenced by the deprotonation. Based on these results it is concluded that upon deprotonation the TEAC value increases (radical scavenging capacity increases) because electron-, not H*-, donation becomes easier. Taking into account that the mechanism of radical scavenging antioxidant activity of the neutral form of the hydroxyflavones is generally considered to be hydrogen atom donation, this implies than not only the ease of radical scavenging, but also the mechanism of antioxidant action changes upon hydroxyflavone deprotonation.

Is MUGA scan necessary in patients with low-risk breast cancer before doxorubicin-based adjuvant therapy? Multiple gated acquisition.

Doxorubicin-based chemotherapy in the adjuvant treatment of breast cancer has become standard. Use of doxorubicin is limited by cardiac dysfunction; however, the incidence is dramatically reduced by limiting the dose to less than 550 mg/m(2). Although the cumulative dose in breast cancer is typically 240 mg/m(2), multiple gated acquisition (MUGA) scans are still recommended for determining cardiac functional status in these patients. To examine the need for this practice, we reviewed 296 patients who underwent surgery for breast cancer at Roswell Park Cancer Institute between July 1997 and December 1998. Fifty-nine of 95 (62%) patients receiving doxorubicin-based regimens, and 3 of 39 (7%) receiving nondoxorubicin regimens had pretreatment MUGA scans. The MUGA scans showed normal results in 58 patients and low-normal in 4 (6.5%), with no wall motion abnormalities encountered. There were no cases where doxorubicin was not used because of an abnormal MUGA scan. There were no cardiac complications in the 59 women who received doxorubicin-based chemotherapy. MUGA will screen out few, if any, women under consideration for doxorubicin-based adjuvant therapy; the decision to avoid doxorubicin can be made based on age and preexisting comorbidity. Guidelines recommending routine use of MUGA before the administration of doxorubicin for adjuvant therapy for breast cancer should be reconsidered.

Heavy metals biosorption from aqueous solution by simple eucaryotic organisms.

Biosorption of cadmium and chromium (III) ions by means of selected yeast species has been estimated. Kinetics and equilibrium measurements have shown the reliable efficiency of both metals removal for Candida tropicalis. The influence of pH and ionic strength on biosorption process has been examined as well. For both metals the adsorption isotherms have been presented. The equilibrium of chromium (III) sorption has appeared compatible to Langmiur model and the maximum sorption capacity has been determined.

Anthelmintic activity of dioxapyrrolomycin.

Dioxapyrrolomycin, pyrrolomycin C, pyrrolomycin D, and piericidin C2 produced by UC 11065 were evaluated as anthelmintics. Assays used to examine these compounds included effects on the free-living nematode Caenorhabditis elegans, ability to clear target nematodes (Haemonchus contortus and Trichostrongylus colubriformis) from jirds, and clearance of Haemonchus contortus from lambs. A crude extract of UC 11065 containing dioxapyrrolomycin, pyrrolomycin C, pyrrolomycin D, and piericidin C2 was active against C. elegans and against H. contortus in the jird. Purified and/or synthetic samples of dioxapyrrolomycin, pyrrolomycin C, pyrrolomycin D, and piericidin C2 were tested in the jird model; only dioxapyrrolomycin exhibited appreciable activity against H. contortus (greater than or equal to 90.9% clearance at 0.33 mg/jird), while none of the compounds showed appreciable activity against T. colubriformis. Dioxapyrrolomycin cleared 99.9% of H. contortus from lambs at 12.5 mg/kg. An in vitro migration study using susceptible and closantel-resistant H. contortus showed there is cross-resistance between dioxapyrrolomycin and closantel. Dioxapyrrolomycin appears to be a narrow-spectrum anthelmintic which works through a closantel-like mode-of-action.

Cognitive-behavioral prevention of postconcussion syndrome.

The symptoms of postconcussion syndrome (PCS) are persistent, and no empirically tested treatment is available. The treatment group (n = 29) in this study received a printed manual and met with a therapist prior to hospital discharge to review the nature and incidence of expected symptoms, the cognitive-behavioral model of symptom maintenance and treatment, techniques for reducing symptoms, and instructions for gradual resumption of premorbid activities. The control group (n = 29) received routine hospital treatment and discharge instructions. Both groups had sustained mild head injuries characterized by Glascow Coma Scale scores of 13-15 on admission without any measurable period of posttraumatic amnesia. Group assignment was random. Groups did not differ significantly on age, Glascow scores, litigation status, gender, or initial number of PCS symptoms. Patients were contacted 6 months following injury by an interviewer who was unaware of group assignment to obtain outcome data. Treated patients reported significantly shorter average symptom duration (33 vs. 51 days) and significantly fewer of the 12 symptoms at followup (1.6 vs. 3.1). Subjects were also asked how often each symptom had occurred in the previous week, and how severe the symptom typically was. The treatment group experienced significantly fewer symptomatic days (.5 vs. 1.3) and lower mean severity levels. Results suggest that brief, early psychological intervention can reduce the incidence of PCS.

Use of radium isotopes to determine the age and origin of radioactive barite at oil-field production sites.

Radium-bearing barite (radiobarite) is a common constituent of scale and sludge deposits that form in oil-field production equipment. The barite forms as a precipitate from radium-bearing, saline formation water that is pumped to the surface along with oil. Radioactivity levels in some oil-field equipment and in soils contaminated by scale and sludge can be sufficiently high to pose a potential health threat. Accurate determinations of radium isotopes (226Ra + 228Ra) in soils are required to establish the level of soil contamination and the volume of soil that may exceed regulatory limits for total radium content. In this study the radium isotopic data are used to provide estimates of the age of formation of the radiobarite contaminant. Age estimates require that highly insoluble radiobarite approximates a chemically closed system from the time of its formation. Age estimates are based on the decay of short-lived 228Ra (half-life = 5.76 years) compared to 226Ra (half-life = 1600 years). Present activity ratios of 228Ra/226Ra in radiobarite-rich scale or highly contaminated soil are compared to initial ratios at the time of radiobarite precipitation. Initial ratios are estimated by measurements of saline water or recent barite precipitates at the site or by considering a range of probable initial ratios based on reported values in modern oil-field brines. At sites that contain two distinct radiobarite sources of different age, the soils containing mixtures of sources can be identified, and mixing proportions quantified using radium concentration and isotopic data. These uses of radium isotope data provide more description of contamination history and can possibly address liability issues.