Enhancing r1 Relaxivity in GdDOTA-Monoamide Complexes through Polar Group-Mediated Ordering of Second-Sphere Water Molecules

This study was designed to test whether the single appended phosphonate group in GdDOTA-1AmP is sufficient for catalyzing the exchange of proton from the single inner-sphere water-exchanging molecule. Unlike the other phosphonate derivatives in this series, GdDOTA-1AmP showed a surprisingly smooth increase in r1 relaxivity from 3.0 to 6.3 mM-1 s-1 at 20 MHz as the pH was lowered from 9 to 2.5. In comparison to the bis-, tris-, and tetrakis-phosphonate analogues, which all show a biphasic dependence of r1 with changes in pH, the unique r1 versus pH characteristics of GdDOTA-1AmP are shown to closely parallel deprotonation of the single appended phosphonate group. Although the tissue biodistribution and clearance rates of GdDOTA-1AmP are more favorable than the other more highly charged phosphonate derivatives, the pH dependency of r1 is substantially reduced at magnetic fields typically used for small animal imaging (7 and 9.4T), so the attractiveness of this new molecule for quantitative imaging of tissue pH is diminished. However, this study provides some new insights into the feasibility of designing pH-responsive MRI contrast agents based upon fundamental acid-base prototropic mechanisms.

Trait mindfulness and the mental and physical health of caregivers for individuals with cancer

BACKGROUND

Mindfulness plays a role in moderating the negative mental and physical health outcomes associated with caregiving. The aims of this study were to examine the relationship between trait mindfulness and the (1) psychological functioning, (2) health behaviors, (3) and physical health of caregivers for individuals diagnosed with cancer.

METHODS

Caregivers completed a battery of questionnaires and examinations assessing sociodemographic characteristics, trait mindfulness, depression, perceived stress, caregiver stress, sleep, diet, physical activity, tobacco use, alcohol use, blood pressure, and BMI. Demographics and cancer diagnostics were collected for the individuals whom caregivers supported. Linear regression, multivariate analyses, and moderator analyses were performed.

RESULTS

Of the 78 caregivers, the mean age was 63.9 (S.D.=13.1); 59% identified as female; 97% identified as White. Regression analyses indicated that caregivers who reported higher levels of trait mindfulness reported significantly less perceived stress (b= -4.38, SE= 0.88, p <.001), lower levels of depression (b= -3.74, SE= 1.10, p = .001), greater caregiver quality of life (b= -9.05, SE=2.12, p < .001), better sleep quality (b= -0.98, SE=0.44, p = 0.03), and lower rates of tobacco use (b= -10.12, SE= 3.43, p =.003). Trait mindfulness was not significantly related to diet, alcohol use, blood pressure, or BMI.

CONCLUSIONS

Higher levels of trait mindfulness are associated with positive mental and physical health measure for caregivers. Future research would benefit from further examining mindfulness-based interventions and their impacts in mitigating the negative toll of caregiving in the context of cancer.

Abstract LB-259: Pb203-AR-RMX conjugates for image-guided TAT of neuroendocrine tumors (NETs)

Objective: The peptide receptor radionuclide therapy (PPRT) for somatostatin receptor positive (SSTR) neuroendocrine tumors (NETs) has emerged more than 15 years ago. The beta-emitter-PRRT has shown to induce objective response in 30-45% of metastatic NETs patients with hematologic/renal toxicity reduced by dose fractionation. The complete response to therapy is rare due to the heterogeneity of NETs; advanced stage of disease at the time of diagnosis; and patient resistance to nonradioactive octreotide and 90Y/177Lu PRRT developed during the therapy. The targeted alpha-emitter therapy of NETs can overcome these limitations. It can enhance the therapeutic response of patients and decrease side-effect and overcome patient resistance of beta-emitter PRRT without significant acute and mid-term toxicity. The RadioMedix and AREVA Med teams together have recently developed several novel 203Pb-peptide derivatives targeting SSTR(+) cancer cells, 203Pb-AR-RMX. The 203Pb is a gamma emitter (279 keV) with t1/2=51.9 h, suitable for single-photon emission computed tomography (SPECT) imaging. The 203Pb is an ideal surrogate for 212Pb α-particle therapy because both isotopes share identical chemical properties. The objective of these studies were: (1) to evaluate the SSTR targeting properties of novel conjugates 203Pb-AR-RMX; and (2) to determine their PK and biodistribution in vivo in SSTR overexpressing xenographs; and (3) to select lead candidate for further pre-IND clinical studies.

Methods: AR-RMX was manufactured under GMP by Macrocylics Inc. The 203Pb-radiolabeling of AR-RMX was carried out under mild conditions. The SSTR targeting properties of 203Pb-AR-RMX were determined in the cellular uptake/competition studies in AR-42J cancer cells and in vivo in SSTR(+) AR42J xenograph mice.

Results: 203Pb-AR-RMX-15 shows exceptionally high tumor-specific accumulation and retention in SSTR(+) AR42J xenograph mice. Tumor uptake of 203Pb-AR-RMX-15 was &gt;14.4 %ID/g at 1h post injection and it remained at this level at least for 24h. The kidneys accumulation of 203Pb-AR-RMX-15 was &gt;13 %ID/g at 1h and varies in different strains of mice but decreased progressively over the 24h. The kidney uptake of agent is similar to previously observed for octreotate labeled with other isotopes. The tumor uptake is significantly higher possible as a result of the change of charge of the 203Pb-AR-RMX-15. The acute hematotoxicity and chronic kidney toxicity is known to limit the doses of 90Y/177Lu PRRT. Preliminary studies of 203Pb-AR-RMX-15 showed that its kidney retention can be reduced by &gt;32% by co-injection of our proprietary AminoMedixTM or Gelofusine-Lysine composition. 203Pb-AR-RMX-15 has shown &gt;98% radio/chemical stability up 7 days post-formulation; no bone marrow uptake of agent was observed in bioD studies of 203Pb AR-RMX-15 done up to 24h post injection. These results allow us to hypothesize that the therapeutic dose of 203Pb/212Pb-AR-RMX-15 is expected to be significantly higher than the dose limiting activity.

Conclusions: 203Pb-AR-RMX-15 showed promising results in vitro and in vivo studies and will be further investigated as a 203Pb/212Pb-labeled theranostics agent. Our “theranostics” approach using 203Pb/212Pb-PRRT has a potential to advance image-guided radionuclide therapy that can detect and deliver therapeutic radiation dose precisely to SSTR(+) NETs.

Citation Format: Izabela Tworowska, Tania Stallons, Amal Saidi, Nilesh Wagh, Federico Rojas-Quijano, Paul Jurek, Garry Kiefer, Julien Torgue, Ebrahim Delpassand. Pb203-AR-RMX conjugates for image-guided TAT of neuroendocrine tumors (NETs) [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 LB-259. doi:10.1158/1538-7445.AM2017-LB-259

The pH sensitivity of -NH exchange in LnDOTA-tetraamide complexes varies with amide substituent

The amide proton exchange rates in various lanthanide(III) DOTA-tetraamide complexes were investigated by CEST as a function of variable chemical structures and charges on the amide substituents. Comparisons were made between YbDOTA-(gly)(4)(-) (Yb-1), YbDOTA-(NHCH(2)PO(3))(4 (5-) (Yb-2) and YbDOTA-(NHCH(2)PO(3)Et(2))(4)(3+) (Yb-3). The general shapes of the CEST vs pH profiles were similar for the three complexes but they showed maximum CEST intensities at different pH values, pH 8.3, 8.8 and 6.9 for Yb-1, Yb-2 and Yb-3, respectively. This indicates that a more negatively charged substituent on the amide helps stabilize the partial positive charge on the amide nitrogen and consequently more base is required to catalyze proton exchange. The chemical shifts of the -NH protons in Yb-1 and Yb-2 were similar (-17 ppm) while the -NH proton in Yb-3 was at -13 ppm. This shows that the crystal field produced by the amide oxygen donor atoms in Yb-3 is substantially weaker than that in the other two complexes. In an effort to expand the useful range of pH values that might be measured using these complexes as CEST agents, the shapes of the CEST vs pH curves were also determined for two thulium(III) complexes with much larger hyperfine shifted -NH proton resonances. The ratio of CEST from -NH exchange in Tm-1 compared with CEST from -NH exchange in Tm-3 was found to be linear over an extended pH range, from 6.3 to 7.4. This demonstrates a potential advantage of using mixtures of lanthanide(III) DOTA-tetraamides for mapping tissue pH by use of ratiometric CEST imaging.

Amphiphilic EuDOTA-tetraamide complexes form micelles with enhanced CEST sensitivity

The synthesis and characterization of four new DOTA-tetraamide ligands having variable alkyl chain lengths (C(1), C(12), C(14), and C(16)) and their respective europium (III) complexes are reported. The three EuL complexes having long alkyl chains spontaneously form micelles of variable size. The critical micelle concentration differed for each complex (lower for the C(16) complex than the C(12) complex) while micelle size increased with increasing alkyl chain length. Chemical exchange saturation transfer (CEST) experiments showed that all four Eu(III) complexes display slow-to-intermediate water exchange kinetics. As expected, the CEST signals in these complexes decreased with increasing temperatures due to faster water exchange but, interestingly, the CEST signals for the C(14) and C(16) complexes approached a maximum near 25°C consistent with exchange limited CEST at or near room temperature. The water residence lifetimes obtained by fitting the CEST spectra to the Bloch equations increased in parallel with an increase in alkyl carbon chain-length. By comparisons with the monomethylamide complex, which served as control, the data illustrate that micelle formation serves to slow the rate of water exchange in these systems. The complex having the largest CEST effect per unit Eu(III) concentration (the C(16) analog) had a detection limit of 5.3 μM. This represents an approximate 250-fold increase in sensitivity relative to the monomethylamide control (detection limit ~1.3 mM). These features highlight the potential of using micelle-based systems such as these as paramagnetic chemical exchange saturation transfer (PARACEST) agents for molecular imaging by MRI.

TmDOTA-tetraglycinate encapsulated liposomes as pH-sensitive LipoCEST agents

Lanthanide DOTA-tetraglycinate (LnDOTA-(gly)₄⁻) complexes contain four magnetically equivalent amide protons that exchange with protons of bulk water. The rate of this base catalyzed exchange process has been measured using chemical exchange saturation transfer (CEST) NMR techniques as a function of solution pH for various paramagnetic LnDOTA-(gly)₄⁻ complexes to evaluate the effects of lanthanide ion size on this process. Complexes with Tb(III), Dy(III), Tm(III) and Yb(III) were chosen because these ions induce large hyperfine shifts in all ligand protons, including the exchanging amide protons. The magnitude of the amide proton CEST exchange signal differed for the four paramagnetic complexes in order, Yb>Tm>Tb>Dy. Although the Dy(III) complex showed the largest hyperfine shift as expected, the combination of favorable chemical shift and amide proton CEST linewidth in the Tm(III) complex was deemed most favorable for future in vivo applications where tissue magnetization effects can interfere. TmDOTA-(gly)₄⁻ at various concentrations was encapsulated in the core interior of liposomes to yield lipoCEST particles for molecular imaging. The resulting nanoparticles showed less than 1% leakage of the agent from the interior over a range of temperatures and pH. The pH versus amide proton CEST curves differed for the free versus encapsulated agents over the acidic pH regions, consistent with a lower proton permeability across the liposomal bilayer for the encapsulated agent. Nevertheless, the resulting lipoCEST nanoparticles amplify the CEST sensitivity by a factor of ∼10⁴ compared to the free, un-encapsulated agent. Such pH sensitive nano-probes could prove useful for pH mapping of liposomes targeted to tumors.

Investigations into whole water, prototropic and amide proton exchange in lanthanide(III) DOTA-tetraamide chelates

Lanthanide(III) chelates of DOTA-tetraamide ligands have been an area of particular interest since the discovery that water exchange kinetics are dramatically affected by the switch from acetate to amide side-chain donors. More recently these chelates have attracted interest as potential PARACEST agents for use in MRI. In this paper we report the results of studies using chemical exchange saturation transfer (CEST) and some more recently reported chelates to re-examine the exchange processes in this class of chelate. We find that the conclusions of Parker and Aime are, for the most part, solid; water exchange is slow and a substantial amount of prototropic exchange occurs in aqueous solution. The extent of prototropic exchange increases as the pH increases above 8, leading to higher relaxivities at high pH. However, amide protons are found to contribute only a small amount to the relaxivity at high pH.

Abstract 4883: Peptide-based PET imaging agents using novel bifunctional chelates and 64Cu

Introduction: Developing peptide-based PET imaging agents would be highly advantageous due to their high affinity and specificity. Two novel bifunctional chelates (BFC), PCTA and Oxo-DO3A, have previously been used to label antibodies with 64Cu. Complexation of 64Cu with PCTA and Oxo-DO3A was more efficient than with DOTA; the PCTA and OXO-DO3A complexes were also more stable and had more favourable pharmacokinetics[1]. Similarly, PCTA was also found to complex 68Ga more efficiently than DOTA[2]. The utility of PCTA and Oxo-DO3A for radiolabeling peptides specific for tumour angiogenesis processes were further investigated.

Methods: The receptor number and affinity of RGD peptides were determined in mouse vascular endothelial cells. Mouse vascular endothelial cells were grown and varying amounts of I-125 echistatin were added to 1 million cells until receptors were saturated. A competitive binding assay, where a set amount of I-125 echistatin was added to the cells in the presence of unlabeled peptides, confirmed the specificity of the peptides for the target. In vivo studies were carried out in HT29 human colorectal tumors grown subcutaneously in RAG2M mice. 64Cu radiolabeled bioconjugates of PCTA, Oxo-DO3A and DOTA were injected with and without excess cyclo-(RGDyK) peptide. The amount of activity in the blood, tumor, liver, kidney and muscle was measured and compared to each of the BFC.

Results: The binding assay revealed the saturation of mouse vascular endothelial cells was achieved when 0.8µci of I-125 echistatin was added. The competitive binding assay indicated an IC50 at a concentration of 9pM of DOTA-RGD. In vivo biodistribution studies showed good tumor to blood ratios for all of the 64Cu radiolabeled bioconjugates and better tumor to muscle ratios for the 64Cu radiolabeled bioconjugates of PCTA and Oxo-DO3A.

Conclusion: The bifunctional chelates PCTA and Oxo-DO3A were found to be effective for radiolabeling peptides with 64Cu; the resulting complexes appear to be more stable than those of DOTA. The data show that PCTA and Oxo-DO3A radiolabel peptides more efficiently than DOTA, and that the resulting complexes are more stable. Angiogenesis in HT-29 tumours was also imaged successfully using the peptides labeled with PCTA and Oxo-DO3A.

References:

1. C.L. Ferreira, D.T.T. Yapp. E. Lamsa, M. Gleave, C. Bensimon, P. Jurek, G.E. Kiefer, Nucl. Med. Biol. 35: 875-882 (2008)

2. C.L. Ferreira, E. Lamsa, M. Woods, Y. Duan, P. Fernando, C. Bensimon, M. Kordos, K. Guenther, P. Jurek, G.E. Kiefer, Bioconj. Chem. 21: 531-536 (2010)

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 4883. doi:10.1158/1538-7445.AM2011-4883

Imaging of Vx-2 rabbit tumors with alpha(nu)beta3-integrin-targeted 111In nanoparticles

Earlier tumor detection can improve 5-year survival of patients, particularly among those presenting with cancers less than 1 cm in diameter. alpha(nu)beta(3)-Targeted (111)In nanoparticles (NP) were developed and studied for detection of tumor angiogenesis. Studies were conducted in New Zealand white rabbits implanted 12 days earlier with Vx-2 tumor. alpha(nu)beta(3)-Targeted (111)In/NP bearing approximately 10 (111)In/NP vs. approximately 1 (111)In/NP nuclide payloads were compared to nontargeted radiolabeled control particles. In vivo competitive binding studies were used to assess ligand-targeting specificity. alpha(nu)beta(3)-Integrin-targeted NP with approximately 10 (111)In/NP provided better (p < 0.05) tumor-to-muscle ratio contrast (6.3 +/- 0.2) than approximately 1 (111)In/NP (5.1 +/- 0.1) or nontargeted particles with approximately 10 (111)In/NP (3.7 +/- 0.1) over the initial 2-hr postinjection. At 18 hr, mean tumor activity in rabbits receiving alpha(nu)beta(3)-integrin-targeted NP was 4-fold higher than the nontargeted control. Specificity of the NP for the tumor neovasculature was supported by in vivo competition studies and by fluorescence microscopy of alpha(nu)beta(3)-targeted fluorescent-labeled NP. Biodistribution studies revealed that the primary clearance organ in rabbits as a %ID/g tissue was the spleen. Circulatory half-life (t(1/2)beta) was estimated to be approximately 5 hr using a 2-compartment model. alpha(nu)beta(3)-Targeted (111)In perfluorocarbon NP may provide a clinically useful tool for sensitively detecting angiogenesis in nascent tumors, particularly in combination with secondary high-resolution imaging modalities, such as MRI.

[Mansonella perstans filariasis after stay in Cameroon. A 19-year-old patient born in Cameroon, in Switzerland for the last 10 years]

After a spending three weeks in Cameroon, a 19-year-old woman presented in the emergency room with sudden lancinating pain in the lower abdomen, predominantly on the right side. A blood smear tested for presumed malaria showed subperiodic microfilariae of the species Mansonella perstans. The patient was treated with mebendazole (Vermox).

Correlation of postoperative axial length growth and intraocular pressure in congenital glaucoma--a retrospective study in trabeculotomy and goniotomy

BACKGROUND

This paper investigates the correlation of postoperative intraocular pressure (IOP) with axial length growth in children who underwent either trabeculotomy (TO) or goniotomy (GO) as primary surgery for congenital glaucoma.

METHODS

Thirty-seven eyes of 21 children with congenital glaucoma who underwent one or two TOs from 1992 to 1997 and 26 eyes of 16 children with congenital glaucoma who underwent one or more GOs from 1974 to 1993 were retrospectively analyzed. None of the eyes had undergone other surgery previously. Thirteen of the TOs were combined with a small trabeculectomy. IOP was measured by handheld applanation tonometry (Perkins). Axial length was measured by ultrasound. The data were analyzed for correlation of postoperative IOP reduction with postoperative axial length growth.

RESULTS

Mean duration of follow-up was 27.3 months in the TO eyes and 37.1 months in the GO eyes. Mean pretreatment IOP before surgery was 28.4+/-6.9 mmHg in the TO eyes and 30.8+/-8.5 mmHg in the GO eyes. Mean IOP at the end of follow-up was 17.5+/-5.8 mmHg in the TO eyes and 17.4+/-10.2 mmHg in the GO eyes. Axial length growth was normalized (proportional or slowed down compared with the nomogram of axial length growth) in 31 of the 37 TO eyes and in 20 of the 26 GO eyes, and was increased in 6 of the TO eyes and 6 of the GO eyes at the end of follow-up. Regarding axial length growth, 6 of 37 TO eyes had increased axial length growth at the end of follow-up. Three of these eyes also did not fulfill the IOP success criterion; 2 of the 3 eyes with normalized IOP had only borderline increased axial length growth. Six of 26 GO eyes had increased axial length growth at the end of follow-up. Five of these eyes did not fulfill the IOP success criterion; 1 eye with normalized IOP had only borderline increased axial length growth.

CONCLUSION

The data show remarkably good correlation of postoperative IOP with postoperative axial length growth. Axial length measurements can therefore help to ascertain halting or progression of congenital glaucoma and thus are considered an important parameter for congenital glaucoma follow-up.

Ankle and first metatarsophalangeal joint dorsiflexion in children with clubfoot

It has been hypothesised that the stiffness of the plantar aponeurosis after clubfoot surgery affects push-off. Because the first metatarsophalangeal (MTP) joint motion relies on the plantar aponeurosis, it was important to determine whether there was a lack of first MTP joint motion in children with clubfoot that also affected push-off. By examining the motion of the first MTP joint using a motion analysis system and passive motion techniques, then correlating these with gait characteristics, the authors found that the first MTP joint was not affected in children with clubfoot. The authors found that a motion analysis system could be used to determine range of motion accurately.

Kinematics and kinetics of the hip, knee, and ankle of children with clubfoot after posteromedial release

Clubfoot is a bony deformity characterized by inversion, adduction, and equinus that often require surgical intervention. This study assessed the gait kinetics and kinematics of children with unilateral and those with bilateral clubfoot, comparing them with age-and gender-matched normal (control) children. Patient satisfaction also was examined using a questionnaire, and muscle strength was evaluated at the ankle and knee. In evaluating the kinematics, it was important to note that deviations occurred at the ankle of children with clubfoot. Differences in kinematics and kinetics at the hip and knee between normal children and those with clubfoot resulted from lack of motion at the ankle. Furthermore, the strength of ankle plantarflexors was weak, which reduced plantarflexion during push-off. This restricted motion may have been caused by residual bony deformities and muscle tightness resulting from the original condition that contributed to muscle stiffness during gait.

A comparison of early intensive methotrexate/mercaptopurine with early intensive alternating combination chemotherapy for high-risk B-precursor acute lymphoblastic leukemia: a Pediatric Oncology Group phase III randomized trial

A prospective, randomized multicenter study was performed to evaluate the relative efficacy of two different concepts for early intensive therapy in a randomized trial of children with B-precursor acute lymphoblastic leukemia (ALL) at high risk (HR) for relapse. Four hundred and ninety eligible children with HR-ALL were randomized on the Pediatric Oncology Group (POG) 9006 phase III trial between 7 January 1991 and 12 January 1994. After prednisone (PDN), vincristine (VCR), asparaginase (ASP) and daunorubicin (DNR) induction, 470 patients received either 12 intensive parenteral treatments of intermediate dose (1 g/m2 each) methotrexate (MTX) and mercaptopurine (MP) over 24 weeks (regimen A) or 12 intensive course of alternating myelosuppressive drug combinations given over 30 weeks (regimen B). These drug combinations included MTX/MP, teniposide (VM-26)/cytosine arabinoside (AC) and VCR/PDN/DNR/AC/ASP. Central nervous system (CNS) prophylaxis was age-adjusted triple intrathecal chemotherapy. Patients with CNS disease at diagnosis were treated with craniospinal irradiation after the intensive phase. Continuation was standard doses of MTX and MP for 2 years. This trial was closed early because of an apparent early difference favoring regimen B. Results show that 470 patients achieved remission (97%). Two hundred and thirty two were randomized to regimen A and 238 to regimen B. The estimated 4-year event-free survival (EFS) for patients treated with regimen A is 61.6 % (s.e. = 3.3%) and with regimen B is 69.4% (s.e. = 3.1%), P = 0.091. Toxicities were more frequent on regimen B. In conclusion, for children with B-precursor ALL at high risk to relapse, early intensification with myelosuppressive combination chemotherapy was more toxic but produced no significant difference in EFS when compared to those treated with parenteral methotrexate and mercaptopurine.

Effects of amitriptyline, amitriptylinoxide, doxepine and clozapine on N-methyl-D-aspartate-evoked release of [3H]-acetylcholine in rat caudatoputamen

The tricyclic antidepressants amitriptyline (CAS 549-18-8), amitriptylinoxide (CAS 4317-14-0) and doxepine (CAS 1229-29-4) as well as the atypical neuroleptic clozapine (CAS 5786-21-0)--all of them substances with well-established clinical efficacy--were investigated in order to elucidate their effect on N-methyl-D-aspartate (NMDA) receptor-mediated events. Modulation of NMDA receptor function was studied using the model of NMDA-evoked [3H]-acetylcholine ([3H]-ACh) release in slices of rat caudatoputamen. All substances reduced [3H]-ACh release in a concentration dependent manner. Significant inhibition occurred in the low micromolar range with the exception of amitriptylinoxide which was less potent in vitro (amitriptylinoxide is not being metabolized in vitro). Amitriptyline and clozapine at 10 mumol/l both decreased the maximum effect of NMDA by around 17%, but left its EC50 unchanged. This suggests a "classical" non-competitive antagonism and excludes an uncompetitive or "use-dependent" antagonism. Considering the important role of NMDA receptor-mediated effects in spinal nociception the analgesic properties of tricyclic antidepressants may partly be explained by their inhibitory action on spinal NMDA receptors, in addition to their enhancement of monoaminergic transmissions in the dorsal horn.

Intensive alternating drug pairs after remission induction for treatment of infants with acute lymphoblastic leukemia: A Pediatric Oncology Group Pilot Study

PURPOSE

Infants with acute lymphoblastic leukemia (ALL) often enter remission; however, they have a high rate of relapse. To prevent relapse, infants' tolerance of and benefits from early intensive rotating drug pairs as part of therapy were studied.

METHODS

After prednisone, vincristine, asparaginase, and daunorubicin induction, 12 intensive treatments (ABACABACABAC) were administered in 30 weeks: A, intermediate dose methotrexate (MTX) and intermediate dose mercaptopurine (MP); B, cytosine arabinoside (Ara-C) and daunorubicin (DNR); C, Ara-C and teniposide (VM-26). Triple intrathecal chemotherapy (Ara-C, MTX, and hydrocortisone) was administered for central nervous system prophylaxis. Continuation therapy consisted of weekly MTX and daily MP for a total of 130 weeks of continuous complete remission.

RESULTS

Thirty-three infants (1 year old or younger) with newly diagnosed ALL were treated. Two infants did not respond to induction, 1 died from sepsis during continuation, 1 received a bone marrow transplant, and 24 relapsed. Median time to relapse was 39 weeks. The event-free survival rate at 5 years was 17% (standard error +/- 7.7%). The most significant toxicities occurred during intensification and included fever-neutropenia and bacterial sepsis.

CONCLUSION

Although early intensive rotating therapy is tolerable, the relapse-free survival rate remains poor for infants treated with the schedule on this protocol.

[Data on the epidemiology of head and neck neoplasms in Hungary]

Oral and pharyngeal cancer mortality of the male population increases in the fastest rate in Hungary. Both oral and pharyngeal as well as laryngeal cancer mortality is the highest in Europe for both sexes. The leading risk factors of them are smoking and drinking together. The per capitam cigarette and alcohol consumption of Hungarian population belong also among the highest in Europe. The authors have examined these damaging habits taking in account the collected data of Hungarian patient's group, the presence of them as risk factors have been compared to the smoking and alcohol consuming habits of the average population collected by microcensus data. Only 4 patients were nonsmokers and nondrinkers among the 145 patients who were interviewed. On the other hand from the same number of the population with the same sex and age distribution 73 did not smoke and drink while 123 patients were smokers and drinkers against the 48 from the population mentioned before. They have found that the two groups have diverged at a level 0.1% significance. Taking in account the fact that the number of patients is relatively low, further data collection is carried on in order to analyse in a more detailed way, but they regard it as proved, according to the recent tests the serious risk role of the two factors for the Hungarian population.

Comparisons of weight-bearing and non-weight-bearing tests of knee proprioception performed by patients with patello-femoral pain syndrome and asymptomatic individuals

OBJECTIVE

To compare non-weight-bearing (sitting) and weight-bearing (standing, with approximately 95% of body weight on the test leg) tests of knee proprioception performed by patients with patello-femoral pain syndrome (PFPS) and asymptomatic individuals.

DESIGN

A repeated measures design, repeated on two occasions.

SETTING

Athletic injuries clinic.

PARTICIPANTS

Seven men and 17 women with PFPS, and age- and sex-matched asymptomatic individuals.

INTERVENTIONS

With their eyes closed, subjects extended their knee in sitting, or flexed their knees in standing, attempting to replicate target angles (15 degrees, 30 degrees, 45 degrees, and 60 degrees knee flexion) measured using an electrogoniometer.

MAIN OUTCOME MEASURE

Observed angle of knee flexion during joint angle replication tests.

RESULTS

Test-retest reliability coefficients (0.17-0.79) and between-session measurement error (+/-2.0 degrees to +/-6.4 degrees) varied widely. There was a tendency for reliability coefficients to be greater and between-session measurement error to be lower, for PFPS subjects, and for sitting tests. No significant differences were observed between the scores of the PFPS and asymptomatic subjects, at any of the four target knee angles.

CONCLUSIONS

Scores in sitting should not be compared with those in standing. Clinically, the low reliability coefficients, large between-session measurement error, and finding of no statistically significant difference between PFPS and asymptomatic subjects suggest that the diagnostic value of the proprioceptive tests used is questionable. Further research is required to develop more precise tests of knee proprioception and to determine if the present results are applicable to other pathologies.

Cytotoxic effects by microinjection of ADP-ribosylated skeletal muscle G-actin in PtK2 cells in the absence of Clostridium perfringens iota toxin

The ADP-ribosylating toxins Clostridium botulinum C2 toxin and C. perfringens iota toxin, which ADP-ribosylate monomeric G-actin at Arg-177 but not the polymeric F-actin, induce depolymerization of the actin cytoskeleton in cultured cells. Since ADP-ribosylated G-actin has properties of a barbed-end-capping protein, we studied whether the ADP-ribosylated actin affects the actin cytoskeleton of PtK2 cells even in the absence of ADP-ribosylating toxin. Skeletal muscle actin was ADP-ribosylated by C. perfringens iota toxin and the toxin was removed using an anti-iota toxin antibody. Microinjection of ADP-ribosylated actin caused retraction of the cell body, redistribution and depolymerization of the actin cytoskeleton in a concentration- and time-dependent manner. The finding that ADP-ribosylated actin affects per se the actin cytoskeleton explains the cytopathic effects of ADP-ribosylating toxins on microfilaments, although F-actin is not directly modified by the toxins.

[The Bullard laryngoscope. An aid in unforseen difficult intubation]

The standard procedure when difficulties are anticipated with intubation, e.g. following the clinical classification as per Mallampati, is the fibreoptic bronchoscopic method applied while the patient is awake. In the case of unexpected difficulties encountered during intubation while the patient is anaesthetized, a scenario that cannot be absolutely ruled out, e.g. in an emergency resection when there is no longer a simple method of returning the patient to the waking condition, and when problems are accentuated by seriously hampered mask respiration, aspiration risk, danger of hypoxia, and visual obstruction by secretions and blood, the fibrebronchoscope is no longer the instrument of choice. A larynx mask or a combination tube is probably a better option. Our experience has shown that the Bullard laryngoscope (BL) can help to improve the situation because, while it has similar advantages to the flexible bronchoscope, it can be operated almost exactly as quickly as a Macintosh intubation spatula. In contrast to the bronchoscope, fibreoptic orientation under impeded visual conditions caused by secretions and blood is, in our experience, much easier. The BL is routinely deployed, as an alternative to the Macintosh instrument, for practice purposes by all our colleagues in the department. It has proved to be remarkably effective: to date it has led to the target quickly and without complications in every case. As examples three case histories selected from a series of cases in which the BL was used have been highlighted.

Intensive alternating drug pairs for treatment of high-risk childhood acute lymphoblastic leukemia. A Pediatric Oncology Group pilot study

BACKGROUND

To prevent drug resistance, the authors designed a protocol that featured early intensive rotating drug pairs as part of the therapy for acute lymphoblastic leukemia (ALL).

METHODS

After prednisone, vincristine, asparaginase, and daunorubicin induction, 12 intensive treatments (ABACABACABAC) were given in 30 weeks: A--intermediate-dose methotrexate (IDMTX) plus intermediate-dose mercaptopurine (MP); B--cytosine arabinoside (AC) plus daunorubicin (DNR); C--AC plus teniposide (VM-26). Triple intrathecal chemotherapy (AC, MTX, and hydrocortisone) was given for central nervous system (CNS) prophylaxis. Continuation therapy consisted of weekly MTX and daily MP until 2.5 years of continuous complete remission had been achieved.

RESULTS

Seventy-four children (age range, 1-19 years) at high risk of relapse were treated. Of 55 with B-lineage (early pre-B, pre-B) ALL, 24 have failed (2 induction failures, 2 deaths from infection, and 20 relapses). The event-free survival (EFS) rate at 4 years was 55.5% (standard error [SE] +/- 7.7%). Of 19 patients with T-cell ALL, 12 have failed (2 induction failures and 10 relapses). The EFS rate at 4 years was 32.6% (SE +/- 26.8%). Toxicities were significantly more common after AC and DNR or AC and VM-26 than IDMTX and MP. There were no toxicity-related deaths during intensive treatments.

CONCLUSION

Early intensive rotating therapy is tolerable and warrants consideration for additional trials of patients with high-risk, B-lineage ALL.

DNA cytophotometric analysis of breast cancer. Follow-up for 10 years

Forty-four cases of newly diagnosed invasive ductal breast cancer were studied by static cytometry at the time of diagnosis and were followed for 10 years to determine if the survival rate correlated with the nuclear DNA measurements. In 22 cases the stem line was in the 2c range, in 15 cases in the 3c range and in 7 cases in the 4c range. Thirty-four percent (n = 15) of the patients died of metastases during the first five years, 11% (n = 5) died of metastases between 5 and 10 years, and 55% (n = 24) survived for > 10 years without metastases. No correlation between increased tumor cell proliferation and recurrence of tumors could be found. In this study all patients with diploid tumors, tumor size T1 and negative lymph node status survived for > 10 years. In the presence of node metastasis (T1N1M0) all patients (n = 4) having tumors with the stem line in the 2c range survived for 5 years but only 2/4 for > 10 years. The percentage of patients surviving for 10 years showed no significant differences between the groups: in the 2c range, 59% (13/22); in the 3c range, 53% (8/15); and in the 4c range, 43% (3/7). The small number of cases does not allow definitive statistical conclusions, although the logistic regression analyses showed that stem line, pT and pN were the important prognostic factors for five-year survival. However, only pT and especially pN were of prognostic value for 10-year survival.

Effects of a three-drug antineoplastic protocol of wound healing in rats: a biomechanical and histologic study on gastrointestinal anastomoses and laparotomy wounds

Using biomechanical and histologic approaches, the effect of perioperative administration of a drug protocol containing 5-fluoruracil, Adriamycin, and mitomycin C (FAM) on the healing of gastrointestinal anastomoses and laparotomy wounds in rats was examined. Application of FAM immediately before operation resulted in significant impairment of wound healing in the early postoperative period. Once the proliferation of fibroblasts and collagen synthesis had led to an increase of mechanical strength, no negative effect on wound healing could be detected applying the same chemotherapeutic agents. These findings indicate the early inflammatory phase of the wound healing process to be most vulnerable to the chemotherapeutic effects. This has significant implications if the theoretical advantages of starting adjuvant chemotherapeutic treatment in the immediate postoperative period are implemented.

Triploidy syndrome in a liveborn female

We present the autopsy report of a liveborn triploid female, born after 36 weeks of gestation, who died at the age of 20 hours. External features were diagnostic: fetal hypoplasia, hypertelorism, microstomia, micro-and retrognathia, preauricular skin tag, low-set ears, and 3-4 syndactylia. All internal organs were hypoplastic. There were atrial and ventricular septal defects. Adrenals and kidneys were fused, the gallbladder was absent, and ovarian hilum cell were found to be hyperplastic. Triploidy, 69xxx, was confirmed cytogenetically. The placenta was hypoplastic and, microscopically, revealed a peculiar type of immaturity, so-called hydatidiform villous hypoplasia, findings which have not been previously reported. We suggest that the generalized fetal and placental hypoplasia and the severe hypoplasia of all internal organs are caused by a proliferative deficiency of the triploid cells. In addition, the nuclear DNA content was determined by cytophotometrically from placental stromal cells and was found to be about 50% above the normal diploid DNA value; i.e., a triploid DNA value was confirmed.

Failed anterior acromioplasty. A review of 51 cases

This report is a retrospective review of 51 patients, each of whom had a failed acromioplasty that was performed after presumptive diagnoses of impingement tendinitis. The purpose of the review is to analyze the failures, define their causes, and make recommendations regarding further management. Average age at time of initial surgery was 40 years (range, 20-64 years), and the follow-up period averaged 5.5 years (range, three to nine years). Thirty-four patients were found to have symptoms and signs that corresponded to a recognized clinical diagnosis and were thought to be sufficient to be a major cause of their pain. Twenty-three had a diagnosis other than continuing impingement. Success of a second surgical procedure was significantly greater in nonworker's compensation (WC) patients than in WC patients. Repeat acromioplasties in WC patients have poor results and are not recommended. Seventeen patients had no clear cause for their continuing shoulder tendinitis; however, time and supportive therapy allowed five patients to improve over an average 18-month period. In all categories, WC patients fared poorly, so prognosis must be guarded in this group. Non-WC patients may be helped with repeat surgery following an appropriate diagnosis for the cause of failure.

Macrophage size determinations in the diagnosis of tuberculous effusions

This study investigated the usefulness of macrophage size determinations in lymphocyte-rich pleural effusions to improve the cytologic diagnosis of tuberculous pleurisy. The size of pleural macrophages was analyzed by quantitative morphometric planimetry in 18 effusions due to tuberculosis, 21 effusions following radiotherapy for malignant disease and 10 effusions due to congestive heart failure. Macrophages were identified and clearly separated from mesothelial cells by latex phagocytosis and immunostaining with the monoclonal antibody My4 (CD14). The mean macrophage area (+/- standard deviation) in tuberculous effusions (92 +/- 14 sq micron) was significantly smaller than in postradiation (141 +/- 28 sq micron) and heart-failure effusions (154 +/- 22 sq micron) (P less than .0001). There was also a smaller ratio of mesothelial cells in tuberculous effusions (0.5 +/- 0.9%) in comparison with effusions following radiotherapy (4 +/- 5%) or congestive heart failure (10 +/- 12%). In summary, this study demonstrated some cytomorphologic parameters that may be helpful in the differential diagnosis of tuberculous effusions.

Antitumor cell and antimetabolic effects of 5-ethyl-2'-deoxyuridine and 5'-substituted 5-ethyl-2'-deoxyuridine derivatives

A series of forty 5'-ester derivatives of 5-ethyl-2'-deoxyuridine (EDU) have been evaluated for their inhibitory effects on the growth and metabolism of murine leukemia L1210 cells. Several EDU esters proved as potent as EDU in their inhibitory effects on L1210 cell growth (inhibitory dose-50:5-10 micrograms/ml), suggesting that these esters were readily hydrolyzed to release the parent compound EDU. That the EDU esters had to be hydrolyzed first to EDU was further suggested by the dependence of their antiproliferative action on the thymidine kinase activity of the cells. It was further ascertained that EDU and its esters acquired their antiproliferative effects by an interaction with dCTP biosynthesis, possibly at the CDP ribonucleotide reductase step. Under conditions where thymidine was readily incorporated, we were unable to demonstrate any incorporation of EDU into L1210 cell DNA.

2-14C-1-Allyl-3,5-diethyl-6-chlorouracil I: Synthesis, absorption in human skin, excretion, distribution, and metabolism in rats and rabbits

With 14C-potassium cyanate as the starting material, 2-14C-1-allyl-3,5-diethyl-6-chlorouracil was synthesized for in vitro and in vivo absorption studies in human skin and for metabolic studies in rats and rabbits. The radioactivity in the horny layer, epidermis, and dermis of the human skin was determined after different intervals of time, and the radioactivity excreted in the urine was measured by collecting samples for 5 days from a patient and also under occlusion conditions. Almost 90% of the radioactivity remained on the surface and approximately 6.28% penetrated and was systemically absorbed. Over a 5-day period, a total of 3.25% was excreted. Almost 3% was systemically absorbed and cumulated in the system. After intraperitoneal application in male and female rats, most of the radioactivity was excreted in the feces and urine, with female rats excreting more in the urine than male rats. The radioactivity rose in the organs in the first 3 hr and then decreased. At the end of 144 hr, no appreciable radioactivity could be found in the organs and tissues, except in the carcass where the cumulation was maximum (1%). After intravenous injection in rabbits, most of the radioactivity (80%) was excreted in the urine and only 4% in the feces. At the end of 96 hr, approximately 3% was cumulated in the body. The drug was quantitatively metabolized in both rats and rabbits: Metabolite 1 (70-85%), Metabolite 2 (10-15%), Metabolite 3 (5-10%), and Metabolite 4 (0.3%).

2-14C-1-Allyl-3,5-diethyl-6-chlorouracil II: Isolation and structures of the major sulfur-free and three minor sulfur-containing metabolites and mechanism of biotransformation

The metabolites of 1-allyl-3,5-diethyl-6-chlorouracil in rabbit urine were isolated by preparative thick-layer, liquid-column, and gas chromatography. With the aid of mass and 1H-NMR spectra, and by comparison with an authentic sample, the major metabolite, 1, was identified as 6,8-diethyl-2-hydroxymethyl-tetrahydrooxazolo-[3,2-c]-pyrimidine-5,7(4H,6H)-dione, Metabolite 2 as 1-allyl-3-ethyl-5-(1-hydroxyethyl)-6-methylthiouracil, Metabolite 3 as 1-allyl-3,5-diethyl-6-methylthiouracil, and Metabolite 4 as 6,8-diethyl-2-hydroxymethyl-tetrahydrothiazolo-[3,2-c]pyrimidine-5,7(4H,6H)-dione. The mechanism of the formation of sulfur-containing metabolites is discussed, and a new metabolic pathway for the formation of methylthio compounds is proposed.

A simple method for the use of gallocyanin-chrome alum as an electron strain

A method has been elaborated for the demonstration of DNA in the electron microscope. The method uses glutaraldehyde fixed tissue pieces from which RNA has been removed by incubation with RNase. DNA is stained by gallocyanin-chrome alum in the tissue block. Embedding and cutting is done in the usual manner. The method is based on histochemical observations at the light microscope level which show sufficient specificity and a good stoichiometry of the staining reaction.

2-14C-1-(2'-deoxy-beta-D-ribofuranosyl)-5-ethyluracil: synthesis and biotransformation in rats

With 14C-urea as the starting material, 2-14C-1-(2'-deoxy-beta-D-ribofuranosyl)-5-ethyluracil [2-14C-beta-5-ethyl-2'-deoxyuridine] was synthesized for metabolic studies. After intravenous administration in rats, the radioactivity disappeared in the blood within 72 hr, being eliminated primarily in the urine (97%). The major elimination took place in the first 24 hr (92%). Little radioactivity was detected in the organs and tissues after 3 days. Approximately 50% of the urine radioactivity probably was due to an unidentified conjugate, 30% was due to Metabolite II, and 20% was unchanged drug. Metabolite II was identified as 5-ethyluracil by mass and 1H-NMR spectra and by comparison with an authentic sample.

Attempts to standardize the screening for antiviral drugs by in vitro tests

Plaque reduction (PR) and persistent infection cell culture (PICC) tests were used as a standard procedure for the selection of effective and well-tolerated antiviral compounds. Antiviral activity and cytotoxicity as well as other characteristics of the test compound, i.e., the development of drug resistance or the potential for activating the multiplication of other viruses can be examined by this method. In the described system analogues of 2'-deoxyuridine were tested against herpes simplex virus.

[Florid oral papillomatosis. A contribution to cytostatic therapy]

Based on the recent clinical experience in treating florid oral papillomatosis (FOP), the only successful therapy appears to be the use of cytostatic agents. The case report of a patient with clinically and histologically confirmed FOP is described to emphasize the advantages of administering Bleomycin intra-arterially (external carotid artery) by means of a Holter catheter. This catheter is used to release pressure in the treatment of internal hydrocephalus and is designed to remain in place for a number of years. The successful treatment of FOP points out the possibility of employing a Holter catheter for administering cytostatic agents in the treatment of malignant neoplasms in the facial area. Cytophotometric examinations of the prickle cells within the FOP mass showed a diploid pattern of DNA distribution similar to that of benigh tumors. However, it is not possible to definitely establish the malignant or benign nature of FOP in this manner.

DNA content of mycosis fungoides cells

DNA content of mycosis infiltrate cells was measured in 5 patients with the Feulgen cytophotometric method in the plaque and tumor stages. In addition, the infiltrate cells were differentiated cytochemically into histiocytes and atypical lymphoid cells with NaF-sensitive naphthol-AS-D-acetate esterase. In no case was an aneuploid stem line demonstrated. However, increasing duration of the tumor stage was associated with a larger proportion of tetraploid and octoploid cells. The DNA histograms also exhibited a local proliferation of atypical lymphoid cells. This proliferation was arrested by cytostatic therapy. Comparison with semi-thin-sections of tumor tissue showed that the mycosis fungoides cells are atypical lymphoid cells. These DNA measurements do not contradict the concept of limited aneuploidy, as reported in cytogenic studies. Thus mycosis fungoides fits in with the DNA distribution pattern in the group of lymphomas.

Comparative studies of the incorporation inhibition of radioactive nucleotides and amino acids in vitro under the influence of adriamycin, bleomycin, and sodium arsenate

The incorporation of 14C-marked nucleotides and amino acids into the nucleic acids and into the cellular protein of PHA-stimulated human lymphocytes was inhibited variably by increasing doses of Adriamycin, Bleomycin and Na2HAsO4. The findings, which were obtained with the aid of the liquid scintillation counter and partly by means of 14C-thymidine-marked autoradiographies shows clearly that Adriamycin causes the strongest incorporation inhibition. In contrast to this, the inhibition caused by Bleomycin and arsenate is considerably less destructive. It was shown by means of cytophoto metrical examinations that Adriamycin is capable of fixing cells in the G2 phase and in the S phase. Cells react similarly to Bleomycin and arsenate. The differential inhibition of nucleic acid and protein metabolism induced by Adriamycin, Bleomycin and arsenate is correlated with a varying responsiveness of lymphocytes to the cytostatically effective substances.

DNA and the cell cycle

The cell cycle and its significance for pathology is reviewed. The molecular basis and questions of regulation in the cell cycle are discussed, along with deviations from the normal cycle in the form of polyploidy formation and aneuploidy in tumor cells. Automated prescreening processes may play a role in the future in daily routine diagnosis. Methods of cytophotometry with the possibility for objective pattern recognition will become significant in pathology in many ways, both in research and in routine work.

[Fumaric acid monoethylester: Effect on DNA-synthesis and preliminary findings in experimental studies in animals (author's transl)]

The incorporation of 14C-Thymidin into DNA of cultured human lymphocytes is depressed by added fumaric acid monoethylester (FSME) depending on the dosage of FSME. The decreased radioactivity in DNA as measured by scintillation counting is paralleled by a concomitant decrease in the labelling index in autoradiograms. Decreasing radioactivity is therefore due to a lower number of DNA synthesizing cells. No selective inhibition of proliferation during one of the cell cycle phases was observed. Especially a G2-block known from other cytostaties is absent. A mean dosis of 6.88 mg FSME per g body weight administered intraperitoneally is lethal to mice. The animal die from diffuse necroses of heart muscle cell. Alterations of other organs are less prominent. At lower doses of FSME the morphology of the organs investigated is altered to a smaller degree.