Visualization and quantification of breast cancer biomechanical properties with magnetic resonance elastography

A quasistatic magnetic resonance elastography (MRE) method for the evaluation of breast cancer is proposed. Using a phase contrast, stimulated echo MRI approach, strain imaging in phantoms and volunteers is presented. First-order assessment of tissue biomechanical properties based on inverse strain mapping is outlined and demonstrated. The accuracy of inverse strain imaging is studied through simulations in a two-dimensional model and in an anthropomorphic, three-dimensional finite-element model of the breast. To improve the accuracy of modulus assessment by elastography, inverse methods are discussed as an extension to strain imaging, and simulations quantify MRE in terms of displacement signal/noise required for robust inversion. A direct inversion strategy providing information on tissue modulus and pressure distribution is described along with a novel iterative method utilizing a priori knowledge of tissue geometry. It is shown that through the judicious choice of information from previous contrast-enhanced MRI breast images, MRE data acquisition requirements can be significantly reduced while maintaining robust modulus reconstruction in the presence of strain noise. An experimental apparatus for clinical breast MRE and preliminary images of a normal volunteer are presented.

Refining the DFNB7-DFNB11 deafness locus using intragenic polymorphisms in a novel gene, TMEM2

The combined DFNB7-DFNB11 deafness locus maps to chromosome 9q13-q21 between markers D9S1806 and D9S769. We have determined the cDNA sequence and genomic structure of a novel gene, TMEM2, that maps to this interval and is expressed in the cochlea. The mouse orthologue of this gene (Tmem2) maps to the murine dn (deafness) locus on mouse chromosome 19. Screens for transmembrane helices reveal the presence of at least one putative transmembrane domain in the TMEM2 protein. To determine whether mutations in TMEM2 cause hearing loss at the DFNB7-DFNB11 locus, we screened the coding region of this gene in DFNB7-DFNB11 affected families by direct sequencing. All DNA variants that segregated with the deafness and changed the predicted amino acid sequence of TMEM2 were common polymorphisms, as demonstrated by allele-specific amplification of pooled control DNA. Northern blot analysis showed no difference in transcript size or expression level of Tmem2 in dn/dn and control mice. The intragenic polymorphisms in TMEM2 represent a novel centromeric boundary for the DFNB7-DFNB11 interval.

Flow cytometric analysis of immunoprecipitates: high-throughput analysis of protein phosphorylation and protein-protein interactions

BACKGROUND

Activation-induced protein phosphorylation can be studied by Western blotting, but this method is time consuming and depends on the use of radioactive probes for quantitation. We present a novel assay for the assessment of protein phosphorylation based on latex particles and flow cytometry.

METHODS

This method employs monoclonal antibodies coupled to latex particles to immobilize protein kinase substrates. Their phosphorylation status is assessed by reactivity with phosphoepitope-specific antibodies. The amount of immobilized protein on the particles was analyzed by direct or indirect immunofluorescence with antibodies to nonphosphorylated epitopes.

RESULTS

The assay allowed measurement of phosphorylation of multiple protein kinase substrates in stimulated T cells, including the zeta chain of the T-cell receptor, ZAP-70, CD3, CD5, SHP-1, and ERK-2, using 1-3 microg of total cell protein per sample. The assay provided high resolution of kinetics of phosphorylation and dephosphorylation. Interactions of protein kinase substrates with associated signaling molecules were demonstrated.

CONCLUSIONS

The novel assay allows high-throughput quantitative measurement of protein modifications during signal transduction.

A phase I trial of docetaxel and gemcitabine in patients with advanced cancer

BACKGROUND

Docetaxel and gemcitabine are active in a broad range of malignancies. The objective of this phase I trial was to determine the maximally tolerated doses of the combination of docetaxel and gemcitabine.

PATIENTS AND METHODS

Patients with advanced cancer, WHO performance status 0-2, who had received up to one prior chemotherapy regimen were treated with gemcitabine on days 1 and 8 and docetaxel on day 8 repeated every 21 days. Prophylactic ciprofloxacin was commenced on day 11 of each cycle and continued until the neutrophil count reached 1.0 x 10(9)/l. G-CSF was not administered. Dose levels studied were docetaxel/gemcitabine: 60/800, 60/1000, 75/1000, 75/1200, 85/1200 and 100/1200 mg/m2.

RESULTS

Thirty-nine patients were entered and all were assessable for toxicity. The highest administered dose level was 100 mg/m2 docetaxel and 1200 mg/m2 gemcitabine with dose limiting toxicities of febrile neutropenia, grade 4 neutropenia > or = 7 days, grade 4 thrombocytopenia, grade 3 stomatitis and/or grade 3 fatigue in three out of six patients. Treatment was well tolerated (40 cycles) in the 10 patients treated at the recommended dose level (85/1200) with only a single episode of febrile neutropenia and grade 3 or 4 non-hematologic toxicity was infrequent. There was no significant pulmonary toxicity. Responses were seen in a range of malignancies including non-small-cell lung cancer.

CONCLUSIONS

The recommended dose level of 85 mg/m2 docetaxel and 1200 mg/m2 gemcitabine has a favourable toxicity profile and is suitable for further investigation in phase II trials. This non-platinum containing regimen warrants further investigation as a potential alternative to platinum containing regimens in non-small-cell lung cancer and other malignancies.

Absence of selection against aneuploid mouse sperm at fertilization

Is there selection against aneuploid sperm during spermatogenesis and fertilization? To address this question, we used male mice doubly heterozygous for the Robertsonian (Rb) translocations Rb(6. 16)24Lub and Rb(16.17)7Bnr, which produce high levels of sperm aneuploid for chromosome 16, the mouse counterpart of human chromosome 21. The frequencies of aneuploid male gametes before and after fertilization were compared by analyzing approximately 500 meiosis II spermatocytes and approximately 500 first-cleavage zygotes using fluorescence in situ hybridization with a DNA painting probe mixture containing three biotin-labeled probes specific for chromosomes 8, 16, and 17 plus a digoxigenin-labeled probe specific for chromosome Y. Hyperhaploidy for chromosome 16 occurred in 20.0% of spermatocytes and in 21.8% of zygotes. Hypohaploidy for chromosome 16 occurred in 17.0% and 16.7% of spermatocytes and zygotes, respectively. In addition, there was no preferential association between chromosome 16 aneuploidy and either of the sex chromosomes, nor was there an elevation in aneuploidy for chromosomes not involved in the Rb translocations. These findings provide direct evidence that there is no selection against aneuploid sperm during spermiogenesis, fertilization, and the first cell cycle of zygotic development.

Phase I and subsequent phase II study of filgrastim (r-met-HuG-CSF) and dose intensified cyclophosphamide plus epirubicin in patients with non-Hodgkin's lymphoma and advanced solid tumors

BACKGROUND

To define a maximum tolerated dose (MTD) for the combination of epirubicin and cyclophosphamide with filgrastim (r-met-HuG-CSF) in patients with advanced solid tumors and non-Hodgkin's lymphoma (NHL).

PATIENTS AND METHODS

Thirty-five patients with advanced solid tumors were enrolled in stages I and II. Twenty-one patients were treated in stage I in sequential cohorts of at least three patients at increasing dosage levels of cyclophosphamide and epirubicin, for up to six cycles every 21 days. At the completion of stage I, a MTD for epirubicin was established. Fourteen patients were treated in stage II, in cohorts of three or more. The epirubicin dose remained constant at the MTD dosage from stage I. Cyclophosphamide was further dose-escalated to establish its MTD. Twenty-one patients with previously untreated non-Hodgkin's lymphoma were treated in stage III with the MTD established in the prior stages.

RESULTS

The MTD in stage I was epirubicin 150 mg/m2 and cyclophosphamide 1500 mg/m2 with cumulative neutropenia as the dose-limiting toxicity (DLT). Cumulative thrombocytopenia prevented further dose-escalation of cyclophosphamide in stage II. The stage III regimen consisted of six, 21-day cycles of epirubicin 150 mg/m2, cyclophosphamide 1500 mg/m2, vincristine 2 mg, and prednisolone 100 mg for five days with filgrastim support. Nineteen of twenty-one patients (90%) completed six cycles of treatment, eight (38%) without dose reduction. Common toxicity criteria (CTC) grade 4 neutropenia (neutrophil nadir < 0.5 x 10(9)/l) was documented in 85 of 118 cycles (72%). Neutropenic fever was documented in 17 of 21 patients (81%) on at least one occasion. Severe thrombocytopenia (< 25 x 10(9)/l) was seen in fourteen of 118 cycles (12%) and increased with cycle number. There was no significant non-hematological toxicity.

CONCLUSION

Significant dose-escalation of epirubicin and cyclophosphamide was possible with filgrastim support. The MTD achieved was approximately double that of standard-dose therapy. This study forms the basis of an ongoing randomized study evaluating dose-intensification in intermediate grade NHL.

Near-field speech intelligibility in chemical-biological warfare masks

It is common knowledge among field personnel that poor speech intelligibility can occur when chemical-biological warfare (CBW) masks are worn: indeed, many users resort to hand signals for person-to-person communicative purposes. This study was conducted in an effort to generate basic information about the problem; its focus was on the assessment of, and comparisons among, the communicative efficiency of seven different CBW units. Near-field word intelligibility was assessed by use of rhyming minimal contrast tests; user and acoustic restrictions were studied by means of diadochokinetic tests and system frequency response. The near-field word intelligibility of six American-designed masks varied somewhat, but overall it was reasonably good; however, a Russian unit did not perform well. Second, three of the U.S. masks were found to produce less physiological restraint than the others, and the Soviet mask produced the greatest physiological restraint. Finally, a few of the CBW masks also exhibited very low levels of acoustic distortion. Accordingly, it was concluded that two of the several configurations studied exhibited superior features. Other factors being equal, they can be recommended for field use and as a basis for the development of future generations of CBW masks. However, it also should be noted that although these devices provided reasonably good speech intelligibility when the listener was close to the talker, they do not appear to do so even at minimal distances.

A randomised phase III study of accelerated or standard fraction radiotherapy with or without concurrent carboplatin in inoperable non-small cell lung cancer: final report of an Australian multi-centre trial

PURPOSE

To investigate the effects separately and together of (a) shortening overall treatment time and (b) giving concurrent carboplatin in patients having radical radiotherapy for inoperable non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Between April 1989 and May 1995, 204 patients with medically inoperable or technically unresectable NSCLC localised to the primary site and regional lymph nodes were randomised to receive one of four treatments using a 2 x 2 factorial design: standard radiotherapy, 60 Gy in 30 fractions in 6 weeks (R6); accelerated radiotherapy, 60 Gy in 30 fractions in 3 weeks (R3); standard radiotherapy as in R6 with carboplatin 70 mg/m2/day for 5 days during weeks 1 and 5 of radiotherapy (R6C); accelerated radiotherapy as in R3 with carboplatin 70 mg/m2/day for 5 days during week 1 of radiotherapy (R3C).

RESULTS

The estimated median survival of all randomised patients was 15.7 months and estimated 2-year survival was 31%. The longest survival was seen in patients randomised to R6C (median 20.3 months, 41% surviving at 2 years) but there were no statistically significant differences between treatment arms or treatment factors (carboplatin versus no carboplatin, accelerated versus conventional radiotherapy). Haematological toxicity was significantly greater in patients treated with carboplatin and oesophageal toxicity was significantly greater and more protracted in patients treated with accelerated radiotherapy.

CONCLUSIONS

This study failed to show a significant survival advantage for any of the treatment arms or factors. Halving overall treatment time resulted in significantly greater oesophageal toxicity with no suggestion of a survival advantage.

Production of 1alpha,25-dihydroxy-3-epi-vitamin D3 in two rat osteosarcoma cell lines (UMR 106 and ROS 17/2.8): existence of the C-3 epimerization pathway in ROS 17/2.8 cells in which the C-24 oxidation pathway is not expressed

The secosteroid hormone 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3] is metabolized into calcitroic acid through the carbon 24 (C-24) oxidation pathway. It is now well established that the C-24 oxidation pathway plays an important role in the target tissue inactivation of 1alpha,25(OH)2D3. Recently, we reported that 1alpha,25(OH)2D3 is also metabolized into 1alpha,25-dihydroxy-3-epi-vitamin D3 [1alpha,25(OH)2-3-epi-D3] through the carbon 3 (C-3) epimerization pathway in human keratinocytes, human colon carcinoma cells (Caco-2), and bovine parathyroid cells. In a previous study, it was demonstrated that 1alpha,25(OH)2-3-epi-D3 when compared to 1alpha,25(OH)2D3 was less active in stimulating intestinal calcium absorption, calcium mobilization from bone, and induction of calbindin D28k. These findings suggest that the C-3 epimerization pathway, like the C-24 oxidation pathway, may play a role in the target tissue inactivation of 1alpha,25(OH)2D3. In this study, we determined the relationship between the C-24 oxidation and the C-3 epimerization pathways by investigating the metabolism of 1alpha,25(OH)2D3 in two rat osteosarcoma cell lines (UMR 106 and ROS 17/2.8). These two cell lines differ from each other in their ability to metabolize 1alpha,25(OH)2D3 through the C-24 oxidation pathway. It has been previously reported that the C-24 oxidation pathway is expressed only in UMR 106 cells but not in ROS 17/2.8 cells. The results of our present study provide new evidence that both cell lines possess the ability to metabolize 1alpha,25(OH)2D3 into 1alpha,25(OH)2-3-epi-D3 through the C-3 epimerization pathway. Our results also reconfirm the findings of previous studies indicating that UMR 106 cells are the only ones which express the C-24 oxidation pathway out of the two cell lines studied. Furthermore, this study reveals for the first time that the C-3 epimerization pathway may become an alternate metabolic pathway for the target tissue inactivation of 1alpha,25(OH)2D3 in some cells, such as ROS 17/2.8, in which the C-24 oxidation pathway is not expressed.

Effect of caffeine consumption on tissue oxygen levels during hyperbaric oxygen treatment

Ten men were exposed to hyperbaric oxygen (HBO2), and their tissue oxygen levels were monitored after they drank either placebo or caffeine beverages. Transcutaneous tissue oxygen (PtcO2) monitor measurements in a normobaric air environment were initially obtained from transducers on the subject's chest and foot. The subjects then consumed either the caffeine (3 mg.kg-1) or the placebo beverage, and after 20 min the subjects were pressurized in a hyperbaric chamber to 2.36 atm abs (1 atm = 101.3250 kPa). The test subjects began breathing 100% oxygen at 2.36 atm abs, 30 min after administration of the experimental beverage, and continued for 30 min, after which the final chest and foot PtcO2 measurements were recorded (1 h after ingestion of the test drink). Each subject underwent a second hyperbaric exposure during which the alternate drink was administered (either the placebo or the caffeine), and PtcO2 measurements were again obtained. The increase in right foot PtcO2 values during HBO2 exposure was significantly smaller after caffeine consumption than after placebo (P = 0.0018).

Magnetic resonance imaging of shear wave propagation in excised tissue

The propagation of shear waves in ex vivo tissue samples, agar/gel phantoms, and human volunteers was investigated. A moving coil apparatus was constructed to generate low acoustic frequency shear perturbations of 50 to 400 Hz. Oscillating gradients phase-locked with the shear stimulus were used to generate a series of phase contrast images of the shear waves at different time-points throughout the wave cycle. Quantitative measurements of wave velocity and attenuation were obtained to evaluate the effects of temperature, frequency, and tissue anisotropy. Results of these experiments demonstrate significant variation in shear wave behavior with tissue type, whereas frequency and anisotropic behavior was mixed. Temperature-dependent behavior related mainly to the presence of fat. Propagation velocities ranged from 1 to 5 m/sec, and attenuation coefficients of from 1 to 3 nepers/unit wavelength, depending on tissue type. These results confirm the potential of elastic imaging attributable to the intrinsic variability of elastic properties observed in normal tissue, although some difficulty may be experienced in clinical implementation because of viscous attenuation in fat.

Nonviral interferon alpha gene therapy inhibits growth of established tumors by eliciting a systemic immune response

A plasmid expression system encoding murine IFN-alpha4 and complexed with a protective interactive noncondensing polymeric (PINC) delivery system was used for in vivo immunotherapy treatment of an immunogenic murine renal cell carcinoma, Renca, and a nonimmunogenic mammary adenocarcinoma, TS/A. Mice bearing established tumors were treated with IFN-alpha/polyvinylpyrrolidone (PVP) expression complexes via direct intratumoral injection. Up to 100% inhibition of tumor growth was observed in the treated mice. By using an optimal dose of 96 and 48 microg of formulated IFN-alpha plasmid for the treatment of Renca and TS/A, respectively, 30% (Renca) and 10% (TS/A) of the treated animals remained tumor free. Inhibition of tumor growth was dependent on activation of the immune system. The antitumor activity elicited by IFN-alpha gene therapy was abrogated when mice were selectively depleted of CD8+ T cells. By contrast, depletion of CD4+ T cells resulted in enhanced tumor rejection following IFN-alpha/PVP treatments. Finally, mice that remained tumor free following IFN-alpha gene therapy displayed immune resistance to a subsequent tumor challenge. These data provide evidence that IFN-alpha gene therapy can be used to induce an efficient antitumor response in vivo.

Trace analysis of SN-38 in human plasma by high-performance liquid chromatography

A reversed-phase high-performance liquid chromatographic method with fluorescence detection was developed and validated for the quantitation of SN-38, the active metabolite of irinotecan (CPT-11), a new anticancer drug. This method uses solid-phase extraction with a C18 column for sample clean-up and concentration following acidification of human plasma with two volumes of 0.1 M HCl. Using blank plasma spiked with SN-38, we found the assay to be linear over the concentration range of 10-500 pM (3.9-195 pg/ml) with acceptable total and within-day imprecision. The recovery of SN-38 ranged from 48.3% (10 pM) to 91.5% (500 pM) whereas that of the internal standard, 20-(S)-camptothecin, was 96.9% (500 pM). This method represents a sizeable increase in sensitivity over other published methods and is shown to be suitable for the measurement of 'trough' concentrations of SN-38 during the treatment of patients with a weekly regimen of irinotecan.

Phase II study of docetaxel and cisplatin in advanced non-small-cell lung cancer

PURPOSE

Docetaxel (Taxotere, Rhone-Poulenc Rorer, Antony, France) and cisplatin are two of the most active single agents used in the treatment of non-small-cell lung cancer (NSCLC). A recently reported phase I study of the combination of docetaxel and cisplatin recommended a dose of 75 mg/m2 of both drugs every 3 weeks for subsequent phase II study.

PATIENTS AND METHODS

Eligible patients were aged 18 to 75 years with a World Health Organization (WHO) performance status < or = 2 and life expectancy > or = 12 weeks, with metastatic and/or locally advanced NSCLC proven histologically or cytologically. Patients were not permitted to have received prior chemotherapy, extensive radiotherapy, or any radiotherapy to the target lesion and must have had measurable disease. Concurrent treatment with colony-stimulating factors (CSFs) or prophylactic antibiotics was not permitted. Docetaxel (75 mg/m2) in 250 mL 5% dextrose was given intravenously (i.v.) over 1 hour immediately before cisplatin (75 mg/m2) in 500 mL normal saline given i.v. over 1 hour in 3-week cycles. Premedication included ondansetron, dexamethasone, promethazine, and standard hyperhydration with magnesium supplementation.

RESULTS

A total of 47 patients, two thirds of whom had metastatic disease, were entered onto this phase II study. The majority of patients were male (72%) and of good (WHO 0 to 1) performance status (85%). All 47 patients were assessable for toxicity and 36 were for response. Three patients were ineligible and eight (17%) discontinued treatment because of significant toxicity. In assessable patients, the overall objective response rate was 38.9% (95% confidence limits [CL], 23.1% to 56.5%), 36.1% had stable disease, and 25% progressive disease. On an intention-to-treat analysis, the objective response rate was 29.8%. Median survival was 9.6 months and estimated 1-year survival was 33%. Significant (grade 3/4) toxicities included nausea (26%), hypotension (15%), diarrhea (13%), and dyspnea mainly related to chest infection (13%). One patient experienced National Cancer Institute (NCI) grade 3 neurosensory toxicity after eight cycles. Grade 3/4 neutropenia was common and occurred in 87% of patients, but thrombocytopenia > or = grade 3 was rare (one patient). Significant (grade 3/4) abnormalities of magnesium levels were common (24%). Febrile neutropenia occurred in 13% of patients and neutropenic infection in 11%, contributing to two treatment-related deaths. No neutropenic enterocolitis or severe fluid retention was reported.

CONCLUSION

Compared with other active regimens used in this setting, the combination of docetaxel and cisplatin in advanced NSCLC is an active regimen with a similar toxicity profile to other combination regimens.

Autism and maternally derived aberrations of chromosome 15q

Of the chronic mental disabilities of childhood, autism is causally least well understood. The former view that autism was rooted in exposure to humorless and perfectionistic parenting has given way to the notion that genetic influences are dominant underlying factors. Still, identification of specific heritable factors has been slow with causes identified in only a few cases in unselected series. A broad search for genetic and environmental influences that cause or predispose to autism is the major thrust of the South Carolina Autism Project. Among the first 100 cases enrolled in the project, abnormalities of chromosome 15 have emerged as the single most common cause. The four abnormalities identified include deletions and duplications of proximal 15q. Other chromosome aberrations seen in single cases include a balanced 13;16 translocation, a pericentric inversion 12, a deletion of 20p, and a ring 7. Candidate genes involved in the 15q region affected by duplication and deletion include the ubiquitin-protein ligase (UBE3A) gene responsible for Angelman syndrome and genes for three GABA(A) receptor subunits. In all cases, the deletions or duplications occurred on the chromosome inherited from the mother.

Epididymal sperm aneuploidies in three strains of rats detected by multicolor fluorescence in situ hybridization

A multicolor fluorescence in situ hybridization (FISH) method was developed to detect aneuploidy and diploidy in epididymal sperm of rats using DNA probes specific for chromosomes 4 and Y. Fourteen healthy young-adult rats from three strains were evaluated: inbred Fisher 344/N/ehs, outbred Sprague-Dawley, and outbred WU Wistar/CPB. The hybridization efficiency of the FISH procedure was > 99.9%, the sex-ratio in sperm was approximately 1 as expected, and there was no significant variation among two independent scorers. No significant variations were detected within or among strains in the frequencies of sperm disomy for chromosome 4 (1-6.5 per 10,000 cell per animal) or the Y chromosome (0-2.5 per 10,000 cells per animal). There was a trend toward increased variation among Wistar rats. The frequencies of sperm-carrying hyper- and hypohaploidy for chromosome 4 were similar, suggesting a symmetrical mechanism of chromosome gain and loss during meiosis. The frequencies of Y-Y-4-4 sperm, which represent genomic meiosis II errors, did not differ significantly across strains (0.1-0.7 per 10,000 cells per strain). This FISH method for detecting aneuploidy in rat epididymal sperm provides a promising interspecies biomarker of male germ cell aneuploidy and introduces the rat as an animal model for investigating the heritable risk to offspring associated with paternal genotype, physiology, and exposure to environmental mutagens. There appear to be no significant differences among young healthy rats, mice, and men in the baseline frequencies of sperm with Y chromosomal disomy, the only chromosome for which data currently exists for all three species.

Clenbuterol induces cardiac hypertrophy with normal functional, morphological and molecular features

OBJECTIVE

Several pharmacological agents have been shown to produce 'physiological' or 'pathological' hypertrophy based on their functional characteristics. The aim of this study was to examine the features of cardiac hypertrophy induced by the selective beta 2-adrenergic agonist, clenbuterol.

METHODS

Cardiac hypertrophy was induced in 7-week-old Sprague-Dawley rats by daily injections of clenbuterol for 3 weeks. Thyroxine and isoproterenol were also used to produce cardiac hypertrophy to serve as positive controls for physiological and pathological hypertrophy, respectively. Left ventricular function was determined using an isolated rat heart preparation. Ventricular samples were used for morphological examination while interstitial collagen was measured using high-pressure liquid chromatography. Expression of sarcoplasmic reticulum Ca(2+)-ATPase2a (SERCA2a) and phospholamban (PLB) were measured by dot blot analysis.

RESULTS

Clenbuterol treatment induced 26% left ventricular hypertrophy. These hearts demonstrated normal systolic isovolumic parameters and diastolic (active relaxation and passive stiffness) function. In addition, left ventricular concentration of collagen and morphology was normal as were the expression of SERCA2a and PLB mRNA.

CONCLUSION

These results suggest that clenbuterol-induced hypertrophy is 'physiological' in terms of its function, extracellular structure and gene expression.

A simple inflammation model that distinguishes between the actions of anti-inflammatory and anti-rheumatic drugs

OBJECTIVE AND DESIGN

To determine the effects of anti-inflammatory and anti-rheumatic drugs on paw swelling and changes in plasma levels of acute phase proteins (APPs) during acute inflammation in the rat.

MATERIALS AND METHODS

Inflammation was induced in rats by the injection of adjuvant and the animals were bled five days later and plasma levels of seromucoid, haptoglobin, caeruloplasmin and albumin were determined spectrophotometrically using a Cobas-bio centrifugal analyzer. The effects of daily administration of a variety of drugs used to treat arthritis were determined on paw swelling and APP levels.

RESULTS

Injection of the adjuvant induced a pronounced change in APP levels which correlated with the increase in paw swelling. In general, the NSAIDs tested significantly reduced paw swelling and significantly increased levels of haptoglobin and caeruloplasmin in a dose-related manner. Two dose-levels of steroids were administered, the higher dose reduced swelling, and reduced levels of seromucoid, haptoglobin and caeruloplasmin, but raised albumin levels; the lower dose also reduced paw swelling, but the only change in APPs was increased albumin levels. Anti-rheumatic drugs such as gold salts reduced levels of some APPs (seromucoid, haptoglobin and caeruloplasmin) without reducing paw swelling. Immunomodulators had a variety of effects on inflammation and APPs depending on mechanism of action.

CONCLUSIONS

The different classes of anti-inflammatory/anti-rheumatic drug tested show distinct profiles of activity against APPs and paw swelling. These differential effects may result from modulation of cytokine activity.

Effects of thyroid hormone on embryonic oligodendrocyte precursor cell development in vivo and in vitro

The oligodendrocyte precursor cell divides a limited number of times before terminal differentiation. The timing of differentiation depends on both intracellular mechanisms and extracellular signals, including mitogens that stimulate proliferation and signals such as thyroid hormone (TH) and retinoic acid (RA) that help trigger the cells to stop dividing and differentiate. We show here that, both in vivo and in vitro, TH is required for the normal development of rodent optic nerve oligodendrocytes, although in its absence some oligodendrocyte development still occurs, perhaps promoted by signals from axons. We also demonstrate that TH from both mother and pup plays a part in oligodendrocyte development in vivo. Finally, we show that precursors in embryonic nerve cultures differ from those in postnatal cultures in two ways: they respond much better to TH than to RA, and they respond more slowly to TH, suggesting that oligodendrocyte precursor cells mature during their early development.

Ro 32-3555, an orally active collagenase inhibitor, prevents cartilage breakdown in vitro and in vivo

1. Ro 32-3555 (3(R)-(cyclopentylmethyl)-2(R)-[(3,4,4-trimethyl-2,5-dioxo-1- imidazolidinyl)methyl]-4-oxo-4-piperidinobutyrohydroxamic acid) is a potent, competitive inhibitor of human collagenases 1, 2 and 3 (Ki values of 3.0, 4.4 and 3.4 nM, respectively). The compound is a selective inhibitor of collagenases over the related human matrix metalloproteinases stromelysin 1, and gelatinases A and B (Ki values of 527, 154 and 59 nM, respectively). 2. Ro 32-3555 inhibited interleukin-1 alpha (IL-1 alpha)-induced cartilage collagen degradation in vitro in bovine nasal cartilage explants (IC50 = 60 nM). 3. Ro 32-3555 was well absorbed in rats when administered orally. Systemic exposure was dose related, with an oral bioavailability of 26% at a dose of 25 mg kg-1. 4. Ro 32-3555 prevented granuloma-induced degradation of bovine nasal cartilage cylinders implanted subcutaneously into rats (ED50 = 10 mg kg-1, twice daily, p.o.). 5. Ro 32-3555 dosed once daily for 14 days at 50 mg kg-1, p.o., inhibited degradation of articular cartilage in a rat monoarthritis model induced by an intra-articular injection of Propionibacterium acnes. 6. Ro 32-3555 is a potential therapy for the treatment of the chronic destruction of articulating cartilage in both rheumatoid and osteoarthritis.

17 alpha-estradiol exerts neuroprotective effects on SK-N-SH cells

Estradiol (E2) has been shown to exert organizational, neurotrophic, and neuroprotective effects in the CNS. The present study assessed the specificity of the neuroprotective effects of estradiol for the potent 17 beta-isomer. SK-N-SH cells from a human neuroblastoma cell line, which we have shown to be estrogen-responsive, were cultured at low or high plating density. Then cells were exposed to 17 beta-E2 (0.2 or 2 nM), 17 alpha-E2 (0.2 or 2 nM), or cholesterol, testosterone, dihydrotestosterone, progesterone, or corticosterone (all at 2 nM). Cultures were insulted by serum deprivation, which caused a profound loss of cells. At 1 or 2 d of serum deprivation and steroid hormone replacement, the protection afforded cells by the steroid addition was assessed. Serum deprivation killed approximately 90% of cells cultured at both low and high plating density. Both 17 alpha- and 17 beta-E2 provided protection of SK-N-SH cells at either plating density. Further, a 10-fold molar excess of tamoxifen antagonized only approximately one-third of the neuroprotective effects of either isomer of estradiol, and a 100-fold excess of tamoxifen had no additional effect on the neuroprotection by 17 beta-E2. By contrast, none of the other steroids tested protected cells from the insult of serum deprivation. These results indicate that the neuroprotective effects of estrogens are not attributable to the general steroid structure, and the majority of the neuroprotection may not be mediated via a tamoxifenantagonized receptor mechanism.

Epidemiologic study of Down syndrome in a racially diverse California population, 1989-1991

The prevalence of Down syndrome was studied among all live births occurring between 1989 and 1991 in the California counties monitored by the California Birth Defects Monitoring Program. Objectives of this study were: 1) to calculate adjusted prevalence rates and quinquennial maternal age-specific risk rates of Down syndrome after adjusting for elective abortion of prenatally diagnosed fetuses; 2) to estimate the impact of prenatal diagnosis and subsequent elective abortion of affected fetuses on the observed prevalence of Down syndrome; and 3) to examine sex ratios among liveborn infants and fetuses with Down syndrome. The racial/ethnic diversity and large size of the population allowed the data to be stratified into five racial categories-Hispanics, whites, Asians, blacks, and others. For the period 1989-1991, the observed prevalence of Down syndrome was 1.13 per 1,000 live births, and the adjusted total prevalence, which took into account the termination of affected pregnancies following prenatal diagnosis, was 1.53 per 1,000 live births. In a comparison of quinquennial maternal age-specific risk rates of Down syndrome by race, Hispanics and whites were the only groups with rates that differed significantly from each other, with Hispanics exhibiting higher rates at maternal ages under 40 years. The overall reduction in live births with Down syndrome in 1989-1991 that could be attributed to prenatal diagnosis and elective abortion of affected fetuses was 25.8%, with a 49.1% reduction being observed at maternal ages > or = 35 years. In 1990-1991, Hispanics had the lowest overall reduction (10.0%), while whites had the highest reduction (46.3%). The male: female ratios among liveborns with Down syndrome were significantly higher than those among all live births, and race had a significant association with sex ratios in both cases and controls. These findings indicate that prenatal diagnosis and elective termination of affected pregnancies has had a substantial impact in reducing the number of liveborns with Down syndrome in the monitored California counties. The effect was greatest for whites and least for Hispanics, with results indicating considerable variation in the use of prenatal diagnostic services among racial/ethnic groups. Estimates of adjusted total prevalence and reduction in live births with Down syndrome in this study should be considered minimal because of some underascertainment of prenatally diagnosed cases.

A phase III study of radiotherapy with and without continuous-infusion fluorouracil as palliation for non-small-cell lung cancer

This study assesses the effect of adding continuous-infusion fluorouracil to palliative thoracic radiation therapy (RT) on the rate and duration of symptom relief in patients with advanced non-small-cell lung cancer (NSCLC). Two hundred eligible patients with NSCLC were randomized to receive either 20 Gy in five daily fractions as palliation for intrathoracic disease or the same RT with concurrent continuous infusion of 1 g m(-2) day(-1) fluorouracil for 5 days. Survival, response and rates of symptom relief in the two groups were compared according to treatment intent, and toxicities were compared according to treatment received. The overall response rate was higher in patients randomized to the combination (29%) than in patients randomized to RT alone (16%) (P = 0.035). However, there were no significant differences between the treatment arms in terms of overall or progression-free survival or in palliation of symptoms. Patients treated with RT plus fluorouracil had significantly more acute toxicity, including nausea and vomiting (P = 0.01), oesophagitis (P = 0.0003), stomatitis (P = 0.0005) and skin reaction (P = 0.003). This study suggests for the first time an interaction between RT and infusional fluorouracil in NSCLC. Although RT plus fluorouracil resulted in a significantly higher response rate than achieved with RT alone, this did not translate into more effective palliation. Because the combination produced significantly more toxicity than RT alone, it is not recommended for the palliative treatment of NSCLC. Nevertheless, these results suggest that opportunities may exist for exploitation of the observed enhancement of antitumour effect in the setting of high-dose radical RT for NSCLC.

Induction of chromosomal aberrations in mouse zygotes by acrylamide treatment of male germ cells and their correlation with dominant lethality and heritable translocations

The objectives of this research were: 1) to investigate the time course of the cytogenetic defects induced by acrylamide (AA) treatment (5 x 50 mg/kg) of male germ cells in first-cleavage zygote metaphases using PAINT/DAPI analysis, and 2) to characterize the correlation between chromosomal aberrations at first cleavage, dominant lethality, and heritable translocations. PAINT/DAPI analysis employs multicolor fluorescence in situ hybridization painting plus DAPI staining to detect both stable and unstable chromosomal aberrations at first-cleavage metaphase of the zygote. High levels of chromosomally defective zygotes were detected after mating at all postmeiotic stages (20-190-fold, P < 0.001). Early spermatozoa (6.5 d post-treatment) were the most sensitive, with 76% of the zygotes carrying cytogenetic defects. A significant 10-fold increase was also detected 27.5 d post-treatment, indicating that AA had a cytogenetic effect on meiotic stages. PAINT/DAPI analysis revealed that: 1) AA-induced chromosomal breaks occurred at random, and 2) the frequencies of symmetrical and asymmetrical exchanges were similar at all mating days, except 9.5 d after AA treatment, where significantly (P < 0.02) more asymmetrical aberrations were found. Furthermore, the proportions of zygotes carrying unstable and stable chromosomal aberrations followed a similar post-treatment time course as the proportions of dominant lethality among embryos and heritable translocations among offspring. These findings indicate that PAINT/DAPI analysis of zygotic metaphases is a promising method for detecting male germ cell mutagens capable of inducing chromosomal aberrations and for evaluating the associated risks for embryonic loss and balanced translocations at birth.

Spontaneous rates of sex chromosomal aneuploidies in sperm and offspring of mice: a validation of the detection of aneuploid sperm by fluorescence in situ hybridization

This study was designed to evaluate the frequency of aneuploid sperm in young adult mice of the genotype (102/E1 x C3H/E1)F1 determined by the fluorescence in situ hybridization (FISH) procedure and to evaluate the frequencies of aneuploid sperm observed by FISH compared with the frequencies of aneuploid offspring. Three-chromosome FISH was applied to determine the fractions of hyperhaploid and diploid sperm with DNA probes specific for chromosomes X, Y and 8. The animals were treated with three common solvents. Sperm smears were prepared for FISH by two similar protocols and were scored by different persons and in two different laboratories. There were no significant differences between scorers or laboratories. The frequencies of the sex chromosome aneuploidies in sperm (Y-Y and X-Y) were compared to the frequencies of mice carrying sex chromosome aneuploidy among controls of the heritable translocation assay in studies conducted from 1975-1995. To identify aneuploid individuals, untreated males and females of the genotype (102/E1 x C3H/E1)F1 were mated to assess their fertility by observing three consecutive litters. Semisterile and sterile animals were further analysed by meiotic cytogenetics and by karyotyping to determine the incidence of reciprocal translocations and sex chromosome aneuploidies (XXY and XYY). Based on the analysis of 175247 sperm and 9840 progeny, the frequency of Y-Y sperm was 0.01% while 0.03% of the offspring were XYY. The frequency of X-Y sperm was 0.005% while 0.02% of the offspring were XXY. The frequencies of aneuploid sex chromosomes were not significantly different between sperm and offspring. This allows two conclusions. First, there was no detectable prenatal selection against these sex-chromosomal aneuploid offspring, and second, germ cell aneuploidy can be reliably determined in mice by sperm FISH analyses.

Paternally inherited chromosomal structural aberrations detected in mouse first-cleavage zygote metaphases by multicolour fluorescence in situ hybridization painting

We describe a fluorescence in situ hybridization (FISH) procedure for assessing zygotic risk of paternal exposure to endogenous or exogenous agents. The procedure employs multicolour FISH with chromosome-specific DNA painting probes plus DAPI staining for detecting both balanced and unbalanced chromosomal aberrations in mouse first-cleavage (1-Cl) zygote metaphases. Four composite probes specific for chromosomes 1, 2, 3 or X, each labelled with biotin, plus a composite probe specific for chromosome Y labelled with digoxigenin, were used. We applied this method to evaluate the effects of paternal exposure to acrylamide, a model germ cell clastogen. First-cleavage zygote metaphases, collected from untreated females mated to males whose sperm or late spermatids were treated with acrylamide, were scored for the induction of structural aberrations using both chromosome painting (PAINT analysis) and DAPI analysis. Structural chromosomal aberrations were observed in the sperm-derived, but not in the egg-derived, pronuclei. While 59.4% of the zygotes had structural aberrations by DAPI analysis, 94.1% of the same zygotes had structural aberrations by PAINT analysis (P < 0.001), illustrating the increased sensitivity for detecting translocations and insertions obtained by adding chromosome painting. These findings show that FISH painting of mouse 1-Cl zygotes when used in conjunction with DAPI analysis is a powerful model for investigating the cytogenetic defects transmitted from father to offspring.

Aneuploid epididymal sperm detected in chromosomally normal and Robertsonian translocation-bearing mice using a new three-chromosome FISH method

We present a new method to detect epididymal sperm aneuploidy (ESA) in mice using simultaneous fluorescence in situ hybridization (FISH) with DNA probes specific for mouse chromosomes X, Y and 8. The method was applied to Robertsonian (Rb) translocation (8.14) heterozygotes and homozygotes as well as the chromosomally normal B6C3F1. The sex ratios of sperm did not differ from the expected 1:1 and the hybridization efficiencies were approximately 99.7% for over 60 000 sperm analyzed. Mice heterozygous for Rb (8.14) produced about tenfold higher rates of sperm with chromosome 8 hyperhaploidy than did Rb (8.14) homozygotes or chromosomally normal mice, while frequencies of sperm with hyperhaploidies for chromosomes X and Y were unaffected in all three lines of mice. Hyperhaploid frequencies obtained with the ESA method were consistent with those of the previous testicular FISH method and were validated by published data obtained by conventional cytogenetic analyses (meiotic metaphase II and first cleavage). Thus, the mouse three-chromosome ESA assay together with the previously developed aneuploidy assay for human sperm constitute a promising pair of interspecific biomarkers for comparative studies of the genetic and physiologic mechanisms of the induction and persistence of aneuploidy in male germ cells.

Abnormal colonic accumulation of fluorine-18-FDG in pseudomembranous colitis

A 51-yr-old man with a history of pancreatic carcinoma was studied with [18F]fluorodeoxyglucose ([18F]FDG) and PET as part of staging for residual disease after chemotherapy. The PET study was performed during a clostridium difficile-associated diarrheal illness. Striking [18F]FDG uptake was demonstrated in the wall of the colon over its entire length. Clostridium difficile associated diarrhea and mechanisms of [18F]FDG uptake in normal and abnormal tissues are briefly reviewed and a mechanism for FDG uptake in this patient is postulated.

CD4+ T-cell induction of Fas-mediated apoptosis in Burkitt's lymphoma B cells

Cytotoxic function of CD4+ Th1 cells is mediated by Fas (CD95, APO-1) and its ligand (Fas ligand). Recent studies using nontransformed B cells and the Ramos Burkitt's lymphoma (BL) B-cell line cells show that CD40 ligation at the B-cell surface by activated, CD40 ligand (CD40L)-bearing, CD4+ T cells upregulates Fas expression on B cells and primes B cells for Fas-mediated death signals. In this work, we examine whether this CD4+ T-cell-dependent molecular pathway for Fas upregulation and B-cell apoptosis reflects a peculiarity of the Ramos B-cell line or is applicable to other Burkitt's tumors as well. In 5 of the 6 Epstein-Barr virus-negative BL cell lines examined, the cells constitutively express undetectable or low levels of Fas and are resistant to Fas-mediated signals induced by monoclonal anti-Fas antibody. All 6 of the BL cell line B cells upregulate Fas in response to CD40 ligation, and in 4 of the cases they become sensitive to Fas-mediated death signals. In one BL cell line, the cells are constitutively sensitive to Fas-mediated cytolysis and are unaffected by CD40 signals. Next, we applied these immunologic manipulations to cells from a refractory clinical sample and observed that the tumor cells could be induced to express Fas and undergo apoptosis in our system. These results establish CD4+ T cells and the Fas-Fas ligand system as important immune regulators of Burkitt's lymphoma B cells and indicate that the susceptibility of tumor cells to Fas-mediated death signals can be modulated by specific activation events at the cell surface.

Aneuploidies and micronuclei in the germ cells of male mice of advanced age

The objective of this research was to determine whether the frequencies of chromosomally defective germ cells increased with age in male laboratory mice. Two types of chromosomal abnormalities were characterized: (1) testicular spermatid aneuploidy (TSA) as measured by a new method of multi-color fluorescence in situ hybridization (FISH) with DNA probes specific for mouse chromosomes X, Y and 8, and (2) spermatid micronucleus (SMN) analyses using anti-kinetochore antibodies. B6C3F1 mice (aged 22.5 to 30.5 months, heavier than controls but otherwise in good health) showed significant approximately 2.0 fold increases in the aneuploidy phenotypes X-X-8, Y-Y-8, 8-8-X and 8-8-Y with the greatest effects appearing in animals aged greater than 28 months. No age effect was observed, however, in X-Y-8 hyperhaploidy. Major age-related increases were seen in Y-Y-8 and X-X-8 hyperhaploidies suggesting that advanced paternal age is associated primarily with meiosis II rather than meiosis I disjunction errors. A approximately 5 fold increase was also found in the frequency of micronucleated spermatids in aged mice when compared with young controls. All micronuclei detected in the aged animals lacked kinetochore labeling, suggesting that they either did not contain intact chromosomes or the chromosomes lacked detectable kinetochores. The findings of the TSA and SMN assays are consistent with meiotic or premeiotic effects of advanced age on germ cell chromosomes, but there were differences in the age dependencies of aneuploidy and micronuclei. In summary, advanced paternal age may be a risk factor for chromosomal abnormalities (both aneuploidy and structural abnormalities) in male germ cells.

The effects of gestation dating on the calculation of patient specific risks in Down's syndrome screening

In Down's syndrome screening using biochemical markers, the marker concentrations are adjusted for the gestational age of the fetus, since they are known to change with gestational age. This adjustment is performed by referring to the population median of each marker for the appropriate gestational age group. The measurement of gestational age is subject to error, whatever method is used, and the population median used is actually the median of a mixture of distributions for different true gestational ages. We show how the proportions in this mixture can be estimated and how the true median corresponding to a given true gestational age can be estimated. For simplicity, we consider the case of using a single marker, namely maternal serum alpha-fetoprotein, and show that the usual estimation method has considerable bias. The effect of this mixture on the calculation of patient-specific risks is discussed and we show that detection rates can be improved by allowing for this error in the dating process. The overall detection rate is increased by about 1%. The increase in detection rate is age-dependent and for some maternal ages the increase is of the order of 5%. The comparative effects of different methods for dating are discussed.

Australasian multicentre phase II study of paclitaxel (Taxol) in relapsed ovarian cancer

BACKGROUND

Until recently there has been no effective therapy for patients with relapsed ovarian carcinoma following standard platinum based chemotherapy. Paclitaxel has recently been approved for clinical use in this malignancy.

AIMS

To evaluate the objective response rate and toxicity of paclitaxel in patients with relapsed ovarian cancer.

METHODS

Paclitaxel was given on an outpatient basis as a three hour infusion every 21 days for a maximum of ten cycles to 72 patients with advanced ovarian cancer previously treated with at least one platinum containing regimen. The starting dose was either 175 mg/m2 (patients with one or two prior chemotherapy regimens) or 135 mg/m2 (three previous regimens). Premedication was given because of the documented risk of hypersensitivity reactions to paclitaxel.

RESULTS

The overall response rate was 22% (95% confidence interval [CI] 13% to 34%) in the 72 patients enrolled in the study: four patients had a complete response. Three patients (4%) ceased treatment due to hypersensitivity reactions. Other significant (WHO grade 3 or 4) toxicities included neutropenia (51%), myalgia (14%), neurological (3%), alopecia (93%) and nausea and vomiting (3%). The estimated median survival of all patients was 9.8 months (95% CI: 9.1-13.0 months) with 44% alive at one year (standard error [SE] 7%).

CONCLUSIONS

This study confirms that paclitaxel given as a three hour infusion has significant activity and acceptable toxicity in advanced ovarian carcinoma previously treated with platinum regimens.

Decision logic for retreatment of asymptomatic lung cancer recurrence based on positron emission tomography findings

PURPOSE

The purpose of the study was to determine if Positron emission tomography (PET) 2-[F-18] fluoro-2-deoxy-D-glucose (FDG) imaging could detect subclinical local lung cancer recurrence and whether retreatment of such recurrence was feasible and beneficial.

METHODS AND MATERIALS

Twenty patients with biopsy proven lung cancer were studied with Positron emission tomography for the purpose of detecting subclinical lung cancer recurrence over a period of 4.25 years. All patients were treated with external radiation as part or all of their therapy. Twenty patients had baseline PET and computed tomography (CT) studies for comparison with later studies. Surviving patients had a total of 40 sequential PET scans and 35 CT scans. The follow-up interval ranged from 5 to 40 months posttreatment. The differential uptake ratio (DUR) was determined for regions of interest of increased FDG uptake.

RESULTS

The median DUR value of the 20 baseline PET studies was 5.59. The DUR value of greater than 3 was empirically selected as being positive for tumor detection. On baseline studies, PET had a 100% correlation with the CT findings in regard to detection of the site of primary tumor involvement. Four of 20 patients showed areas of discordance in the mediastinal and hilar areas on initial PET and CT studies. Seven of 17 patients showed discordant posttreatment PET-CT findings. Two false positive PET studies were due to radiation pneumonitis and one to macrophage glycolysis in tumor necrosis. For detection of asymptomatic tumor recurrence, analysis of sequential PET and CT studies, biopsy results, and the patient's clinical course suggested that PET had a sensitivity of 100%, specificity of 89.3%, and accuracy of 92.5%. Computerized Tomography was found to have a sensitivity of 67%, specificity of 85%, and accuracy of 82% for detection of such early-stage recurrence. Five patients went on to have retreatment with external irradiation based upon the PET evidence. Four retreated patients had biopsies that corroborated the positive PET findings, and one patient was retreated on the basis of the qualitative appearance of the posttreatment PET study. Two of the five retreated patients remain alive without evidence of tumor to 34 months following initial therapy.

CONCLUSION

Positron emission tomography scanning appears to be effective in detecting and following the progression of recurrent lung cancer. Retreatment of patients with asymptomatic recurrent tumor has resulted in absent or decreased FDG activity. Monitoring of patients with PET may provide prolonged survival in patients who otherwise would fail treatment because of local tumor recurrence.

Shave excision of benign papular naevocytic naevi

Patients frequently request removal of benign papular naevi for cosmetic or functional reasons. Shave excision plus electrocautery is probably the most widely used method of removal, but this method is said to result in retained hair or pigment if deeply pigmented or hairy naevi are treated. In a prospective study, 82 benign papular naevi of all types were treated by shave excision using hot-wire electrocautery for haemostasis. Details of the naevi were accurately recorded before treatment and reassessment of shave sites carried out at 6-8 months. At review, a scar was visible at only 63% (52/82) of shave sites and all of these were cosmetically acceptable. Only 27% (15/55) of the initially pigmented naevi retained pigment and only 24% (5/21) of the initially hairy naevi regrew hair. Shave excision and electrocautery of benign naevi, including hairy and deeply pigmented ones, produce excellent cosmetic results. The patient must be warned that there is a potential risk of a scar or pigment remaining after shave excision of any naevus and for hair regrowth after shave excision of hairy naevi.

Errors in quantitative dynamic three-dimensional keyhole MR imaging of the breast

Three-dimensional (3D) keyhole magnetic resonance (MR) imaging has been proposed as a means of providing dynamic monitoring of contrast agent uptake by breast lesions, with complete breast coverage and high spatial and temporal resolution. The 3D keyhole technique dynamically samples the central regions of k-space in both phase-encoding directions and provides high-frequency data from a precontrast acquisition. Errors due to data truncation with two-dimensional and 3D region-of-interest measurements are estimated from a numerical simulation of various implementations of the 3D keyhole technique. Errors were found to increase with increasing temporal resolution and reduced object size. Errors of 75% are possible for objects with a diameter approaching 1 pixel when a 3D keyhole implementation that samples 50% of phase-encoding data in each direction is used. Preliminary clinical images with this approach illustrate artifacts consistent with inadequate k-space sampling.

The immunogenicity of MUC1 peptides and fusion protein

Mucin 1 (MUC1) is highly expressed in breast cancer, has an ubiquitous distribution and, due to altered glycosylation, peptides within the VNTR are exposed. These peptides are the target for anti-MUC1 antibodies, which give a differential reaction on cancer compared with normal tissue. The amino acids, APDTR or adjacent amino acids, are highly immunogenic in mice for antibody production (after immunisation with either breast cancer cells, human milk fat globule (HMFG) or the VNTR peptide). In addition, human studies show that this region of the MUC1 VNTR functions as target epitopes for cytotoxic T cells. We have performed preclinical and clinical studies to examine the immune responses to MUC1 in mice and humans: (a) MUC1+ 3T3 or P815+ 3T3 cells in syngeneic mice are rejected, with the generation of both cytotoxic T lymphocyte (CTL) and DTH responses and a weak antibody response and a weak antibody responses; this type of immunity gives rise to total resistance to re-challenge with high doses of these tumors; (b) immunisation with peptides (VNTR x 2), a fusion protein (VNTR x 5), or HMFG leads to no CTLs, DTH, good antibody production and weak tumour protection (to 10(6) cells, but not 5 x 10(6) cells) (possibly a TH2 type response); (c) immunisation with mannan-fusion protein (MFP) gives rise to good protection (resistance to 50 x 10(6) cells), CTL and DTH responses and weak antibody responses (possibly a TH1 type response, similar in magnitude to that obtained after tumor rejection); (d) established tumors can be rapidly rejected by delayed treatment of MFP; (e) the CTL responses are MHC restricted (in contrast to the human studies); (f) APDTR appears not to be the T cell reactive epitope in mice. On the basis of these findings, two clinical trials are in progress: (a) VNTR x 2 (diphtheria toxoid) which gives rise to some T cell proliferation, DTH and antibody responses in some patients and (b) an MFP trial. The ability to alter the immune response towards cellular immunity with mannan or to humoral immunity with peptides, allows the immune response to be selectively manipulated.

A phase II trial of zeniplatin in metastatic melanoma

A third-generation platinum analogue, zeniplatin, was administered at a dose of 145 mg/m2 intravenously over 60-90 minutes every 21 days as the initial chemotherapy to 21 patients with metastatic melanoma. Prehydration and mannitol diuresis was introduced after the first 7 patients. There were 17 males and 4 females. The median age was 52 (range: 29-81). ECOG performance status was 0 in 10 patients, 1 in 8 patients and 2 in 3 patients. Major disease sites were lymph nodes, skin, lung, liver, and bone. Patients received a median of 2 cycles (range: 1-7). Two patients achieved partial responses. One with nodal disease progressed after 166 days and the other with buccal mucosal disease after 142 days. A third patient showed partial regression of nodal disease but developed cerebral metastases. Gastrointestinal toxicity included WHO grade 3 vomiting in 8 patients and nausea in 2. Antiemetics were used, but ondansetron was not available. WHO grade 3 hematologic toxicities included neutropenia in 8 patients and anemia and thrombocytopenia in 1 patient. Thrombocytosis was seen in 35% of courses. Dosage reduction was required in 15% of courses and escalation in 5% of courses. Three patients developed phlebitis related to the infusion. One patient developed a reversible rise in serum creatinine, but, unlike other studies, no severe nephrotoxicity was reported. Zeniplatin demonstrated only modest activity in melanoma with significant gastrointestinal and hematologic toxicity.

Aneuploidy in late-step spermatids of mice detected by two-chromosome fluorescence in situ hybridization

A multicolor procedure employing fluorescence in situ hybridization is described for detecting chromosomal domains and germinal aneuploidy in late-step spermatids in mice using DNA probes specific for repetitive sequences near the centromeres of chromosomes 8 and X. These probes were nick-translated with biotin- or digoxigenin-labeled nucleotides, and were detected with FITC or rhodamine. Probe and hybridization specificities were confirmed using metaphase chromosomes from spleen and bone marrow cells as well as from primary and secondary spermatocytes. Late-step spermatids, identified in testicular preparations by their hooked shape, yielded compact fluorescence domains in approximately 50% and > 99% of cells when hybridized with probes for chromosomes X and 8, respectively. In a survey of > 80,000 late-step spermatids from 8 healthy young adult C57BL/6 or B6C3F1 mice, approximately 3/10,000 spermatids had fluorescence phenotypes indicative of X-X or 8-8 hyperhaploidy. These frequencies are consistent with published frequencies of aneuploidy in meiotic metaphase II and first cleavage metaphases of the mouse, providing preliminary validation of sperm hybridization for the detection of aneuploidy. No significant animal or strain differences were observed. In addition, the hyperhaploidy frequencies for murine spermatids were indistinguishable for those for sperm from healthy men obtained by a similar hybridization procedure. These procedures for detecting aneuploid male gametes are examples of "bridging biomarkers" between human and animal studies. They have promising applications for investigations of the genetic, reproductive, and toxicological factors leading to abnormal reproductive outcomes of paternal origin.

A phase III study of accelerated radiotherapy with and without carboplatin in nonsmall cell lung cancer: an interim toxicity analysis of the first 100 patients

PURPOSE

In 1989 we initiated a multicenter randomized trial to determine if accelerated radiotherapy with or without concurrent carboplatin improves local control and survival in patients with limited nonsmall cell lung cancer. This interim analysis was performed on the first 100 patients to determine whether the toxicity of the four treatment arms is acceptable.

METHODS AND MATERIALS

One hundred patients with limited nonsmall cell lung cancer have been randomized to receive one of four treatments: arm I, radiotherapy 60 Gray (Gy) in 30 fractions in 6 weeks; arm II, accelerated radiotherapy 60 Gy in 30 fractions in 3 weeks; arm III, radiotherapy as in arm I plus carboplatin 350 mg/m2 during weeks 1 and 5 of radiotherapy; arm IV, radiotherapy as in arm II plus carboplatin 350 mg/m2 during week 1. Survival was measured for the group as a whole and treatment-related toxicities in the four arms were compared.

RESULTS

The estimated median survival for all 100 patients was 17.1 months with 33% estimated survival at 2 years. The major toxicities were hematologic and esophageal. Patients receiving carboplatin had more neutropenia (p < 0.0001) and thrombocytopenia (p = 0.002) than patients receiving radiotherapy alone, and this was most marked in patients on arm III. Both carboplatin and accelerated radiotherapy separately caused more severe esophagitis when compared to conventional radiotherapy alone (p = 0.011 and p = 0.0017, respectively). Esophagitis was more prolonged in patients having accelerated radiotherapy (p < 0.0001, median duration 3.2 months compared with 1.4 months for patients receiving conventional fractionation). Six patients (23%) treated on arm II have required dilatation of esophageal stricture, one dying with a laryngo-esophageal fistula.

CONCLUSION

In patients receiving radiotherapy for unresectable lung cancer, overall treatment time can be halved and carboplatin administered concurrently with increased but acceptable esophageal and hematologic toxicity.

Estradiol enhances brain glucose uptake in ovariectomized rats

This study was designed to investigate the effects of 17 beta-estradiol benzoate (E2B) on brain glucose uptake and transport across the blood-brain barrier (BBB). Both a time- and dose-response evaluation of the effect of E2B on glucose uptake in the central nervous system (CNS) were conducted. E2B, in doses ranging from 1 to 100 micrograms/kg body weight, was injected subcutaneously at 2 to 24 h prior to evaluation. The 4-h time point and 10 micrograms/kg dose of E2B produced the most widespread increases in glucose uptake. Six regions responded to E2B with elevated glucose uptake by as much as 120% when compared to oil-treated controls. We then evaluated the effects of E2B on transport of glucose across the BBB. E2B significantly increased the extraction of labeled sugar across the BBB by 40% without affecting extraction of the internal standard. Collectively, these studies indicate that physiological levels of estradiol (E2) may play an important role in modulating cerebral glucose homeostasis.

Prevalence of asthma and wheeze in Hong Kong schoolchildren: an international comparative study

Comparison of asthma prevalence between populations is difficult because of lack of uniformity of methodology and agreement on the definition. This study aims to determine and compare the prevalence of wheeze and respiratory symptoms in Hong Kong schoolchildren with that in Melbourne children by using identical questionnaires. Schools were randomly selected in different regions of Hong Kong and three age groups (7, 12 and 15 yrs) were chosen for the study. The Chinese version of the questionnaire used in a recent Melbourne survey was distributed to children for completion by their parents. A total of 1,800 questionnaires was issued and 1,689 returned (response rate = 94%). The prevalence of wheeze in the past 12 months was 7 (5.1-8.0), 5 (3.0-6.7) and 4 (1.7-5.6) % for 7, 12 and 15 year olds, respectively. The prevalence of a history of asthma in the respective age groups was 10 (7.1-12.9), 8 (7.5-9.2) and 7 (5.0-9.6) %, respectively. Whilst a history of wheeze ever was more common in boys than in girls and 12 yr olds (14% vs 5%), wheeze in the past 12 months was more common in boys than in girls aged 7 yrs (9 vs 4%). We conclude that the prevalence of wheeze and asthma in school children was low in Hong Kong compared to Melbourne. Environmental differences between the two regions may be important in the pathogenesis.

Dynamic spin-echo imaging: theoretical assessment and implementation

A spin-echo method for obtaining dynamic magnetic resonance (MR) images is described. The method combines the RARE (rapid acquisition with relaxation enhancement) pulse sequence with a data acquisition scheme in which only a centric fraction of the raw data is sampled to increase the time resolution of the dynamic images. The missing high-resolution data are supplied from reference images. By these means, an effective time resolution of about 10 seconds per image is achieved, which is suitable for diagnostic assessment of contrast enhancement procedures. A promising clinical application is contrast-enhanced MR imaging of the pituitary. Although the resolution of small objects in this size range is potentially degraded, this shortcoming is compensated for with use of variable refocusing flip angles. In the context of pituitary imaging, the centric 30%-40% of the raw data is shown to be the optimal fraction to acquire for the low-resolution dynamic images. Ten patients with previous history of pituitary disease have been imaged with dynamic and conventional spin-echo techniques. In six of these patients, an equivalent diagnosis was reached with dynamic and conventional images, while in two, only the dynamic images showed the lesion; in the final two patients, only the conventional images showed the lesion.