Cytogenetic findings in 73 osteosarcoma specimens and a review of the literature

Tumor-specific chromosomal abnormalities have been identified in several histologic subtypes of sarcomas. Characterization of recurrent chromosomal abnormalities has provided direction for molecular investigations of pathogenetically important genes. Cytogenetic reports of osteosarcoma, the most common primary malignant bone tumor, are relatively rare. In this study, 73 osteosarcoma specimens from 51 patients were cytogenetically analyzed following short-term culture. Clonal chromosomal abnormalities were detected in 47 and included one haploid specimen, 18 near-diploid specimens, 17 near-triploid, 8 near-tetraploid, 1 near-hexaploid, and 2 specimens with multiple clones of different ploidy levels. Examination of the present data and previously published data (111 clonally abnormal osteosarcoma specimens) reveals that chromosomal bands or regions 1p11-13, 1q10-12, 1q21-22, 11p15, 12p13, 17p12-13, 19q13, and 22q11-13 are most frequently rearranged and the most common numerical abnormalities are +1, -9, -10, -13, and -17. Partial or complete loss of the long arm of chromosome 6 also was seen in all cases of the present study and all previously published cases describing structural abnormalities of 6q. Parosteal osteosarcoma, a prognostically favorable osteosarcoma subtype, was characterized by the presence of a ring chromosome accompanied by no or few other abnormalities. Complex karyotypes were seen nearly exclusively in the high-grade lesions. These findings indicate that specific chromosomal bands and/or regions are nonrandomly involved in osteosarcoma and may provide useful clinical information.

Improving the predictability of intraocular lens power calculations

We reviewed the intraocular lens power calculations on 512 posterior chamber lens implantations and determined four ways to reduce the estimated 5% incidence of large postoperative refractive "surprises" (greater than 2 diopters [D]): First, preoperatively identify those patients who have greater than a 1-D difference between the theoretical and linear regression formulas. Second, repeat axial length and corneal power measurements in these patients to eliminate random error. Third, develop an individualized theoretical formula that accounts for constant bias. Fourth, encourage manufacturers to improve instrumentation for measuring corneal power and axial length. We also examined the disparity between the linear regression formula and the curvilinear theoretical formula.

Body fat distribution measured with CT: correlations in healthy subjects, patients with anorexia nervosa, and patients with Cushing syndrome

Computed tomography (CT) was used to study fat distribution in three groups of women of comparable age: 39 healthy volunteers, 15 patients with anorexia nervosa, and seven with Cushing syndrome. Patients with anorexia nervosa had a fivefold decrease in subcutaneous fat and only a twofold decrease in intraabdominal fat compared with the values for the volunteers. Patients with Cushing syndrome had less than a twofold increase in subcutaneous fat and greater than a fivefold increase in intraabdominal fat compared with values for the healthy subjects. These findings suggest that fat in different body compartments responds differently to disease processes and that CT can be used to measure these changes.

Larger numbers of CD4(bright) dendritic cells in donor bone marrow are associated with increased relapse after allogeneic bone marrow transplantation

Relapse is the major cause of death after allogeneic bone marrow transplantation (BMT). This study tested the hypothesis that the numbers of donor mononuclear cells, lymphocytes, and CD34(+) cells influence relapse and event-free survival (EFS) after BMT. The study population consisted of 113 consecutive patients with hematologic malignancies who underwent non-T-cell-depleted BMT from HLA-matched siblings. Sixty-four patients had low-risk diagnoses (ALL/AML CR1, MDS RA/RARS, and CML CP1); 49 patients had high-risk diagnoses (all others). CD34(+) cells, T cells, B cells, natural killer cells, monocytes, and a rare population of CD3(-), CD4(bright) cells in the allografts were measured by flow cytometry. The CD3(-), CD4(bright) cells in bone marrow had the same frequency and phenotype as CD123(bright) type 2 dendritic cell (DC) progenitors, and they differentiated into typical DCs after short-term culture. Cox regression analyses evaluated risk strata, age, gender, and the numbers of nucleated cells, CD3(+) T cells, CD34(+) hematopoietic cells, and CD4(bright) cells as covariates for EFS, relapse, and nonrelapse mortality. Recipients of larger numbers of CD4(bright) cells had significantly lower EFS, a lower incidence of chronic graft-versus-host disease (cGVHD), and an increased incidence of relapse. Recipients of larger numbers of CD34(+) cells had improved EFS; recipients of fewer CD34(+) cells had delayed hematopoietic engraftment and increased death from infections. In conclusion, the content of donor CD4(bright) cells was associated with decreased cGVHD and graft-versus-leukemia effects in recipients of allogeneic bone marrow transplantation, consistent with a role for donor DCs in determining immune responses after allogeneic BMT.

Translocation t(1;3)(p36.3;q25) is a nonrandom aberration in epithelioid hemangioendothelioma

The cytogenetic findings for two epithelioid hemangioendotheliomas are reported. An identical chromosomal translocation involving chromosomes 1 and 3 [t(1;3)(p36.3;q25)] was detected in both cases of epithelioid hemangioendothelioma, possibly representing a characteristic rearrangement for this histopathologic entity. The presence of clonal karyotypic abnormalities supports a neoplastic origin for the epithelioid variant of hemangioendothelioma. Identification of the 1;3 translocation may be useful diagnostically. Should additional studies confirm these data, this could lead to the identification of the gene(s) central to this neoplastic process.

MRI of breast cancer: influence of chemotherapy on sensitivity

MR mammography (MRM) seems to be a sensitive method for detection of breast cancer. The effect of cytotoxic agents on the dynamics of contrast medium uptake in primary breast carcinoma or recurrent disease is not known. This study addresses this question and evaluates MRM as a method of monitoring therapeutic success. A total of 13 patients (age range 34-62 years) with histologically confirmed breast cancer were investigated. The patients received neoadjuvant intravenous (iv) chemotherapy. MRM and interpretation of the dynamic measurements were performed in a standardized manner after positioning the patient in a double breast coil. A gradient echo sequence (Flash 3D, TE 5 ms, TR 12 ms, flip angle 25 degrees) was acquired before and 1, 2, 3 and 8 min after intravenous injection of Gd-DTPA 0.15 mmol kg-1 body weight. A T2 weighted SE sequence (TE 103 ms, TR 6900 ms, 4 mm, field of view 350 mm) was also obtained. MRM was performed prior to histological evaluation and after chemotherapy. All cases of malignancy were correctly diagnosed with MRM. Based on MR findings, eight patients were classified as "responders" and the remaining as "non-responders". In the "responders" a flattening of the Gd-DTPA uptake curve after the first cycle of chemotherapy of complete absence of Gd-DTPA uptake after the fourth cycle was observed. The change in Gd-DTPA uptake behaviour led to an underestimation of the extent of tumour in two patients and false negative findings in four patients. MRM provides information regarding response to therapy following the first cycle. MRM does not provide information regarding invasive tumour tissue in "responders".

Intravascular ultrasound-guided percutaneous fenestration of the intimal flap in the dissected aorta

BACKGROUND

Aortic dissection with branch obstruction is associated with high morbidity and mortality. Fenestration of the dissection flap to relieve distal vessel ischemia is at present largely performed surgically. The surgical mortality and morbidity are high, because most patients are poor candidates for anesthesia or surgery.

METHODS AND RESULTS

Nine percutaneous fenestrations (one with additional stenting of the infrarenal true aortic lumen) were performed under local anesthesia in seven patients with aortic dissection. The presenting symptoms were abdominal angina or claudication. By the transfemoral approach, the intimal flap was initially punctured with a needle-catheter combination through which a guidewire was placed across the dissection flap. The fenestration was carried out with a balloon catheter introduced over the guidewire. The procedure was performed under on-line guidance with intravascular ultrasound imaging. The procedure was performed successfully and without complications in all patients. After intervention, symptoms resolved in all seven patients.

CONCLUSIONS

Intravascular ultrasound-guided percutaneous fenestration of the intimal flap in symptomatic aortic dissections with distal vessel involvement is a technically feasible and safe procedure that can effectively relieve the patient's symptoms.

Magnetic susceptibility effects of trabecular bone on magnetic resonance imaging of bone marrow

High-field spectroscopic studies at 5.88 tesla (T) indicate significant T2* shortening of water in suspensions of powdered bone, interpreted to be a result of magnetic susceptibility differences between bone particles and water. The authors investigated the effects of magnetic susceptibility differences between trabecular bone and water on magnetic resonance (MR) images at 0.6 T. The phantom was constructed of macerated intact trabecular human bone immersed in water. Although susceptibility-induced magnetic field inhomogeneities were detected by spectral line broadening by using an asymmetric spin-echo technique, the results show only a modest T2* shortening at this field strength. As expected, no T1 effect of trabecular bone was observed. Although susceptibility effects of trabecular bone may have a small impact on the signal intensity of MR images of bone marrow at midfield strength, the observed field strength dependence of these effects would predict significant susceptibility effects on clinical images at higher field strength.

Nipple discharge and abnormal galactogram. Results of a long-term study (1964-1990)

In case of abnormal nipple discharge of the female breast, galactography can detect variations of ductal calibre, intraductal alterations and ductal discontinuities. Between 1964 and 1990 we examined 2588 women by galactography and performed 826 duct excisions. In one out of 8 patients (13.4%) we diagnosed invasive carcinoma or ductal carcinoma in situ. In more than 40% a solitary ductal papilloma was detected. 13.7% of the patients were found to have extensive intraductal solid papillary or adenomatous epithelial proliferations. Comparison with collected statistical data reveals that other investigators are able to detect malignant changes in 1-23% of cases. We have managed the largest number of cases and have diagnosed pathologic ductal secretion in more than 3% of women we screened by physical inspection, mammography and sonography. The colour of the ductal discharge is of minor importance, as histologic analysis is mandated by the presence of ductal system alterations.

Fate of the transpedicular intervertebral bone graft after posterior stabilisation of thoracolumbar fractures

The authors present a retrospective clinical and radiological study addressing the outcome after posterior stabilisation of thoracolumbar fractures with intervertebral fusion via transpedicular bone grafting. The study included computed tomographic (CT) scan after implant removal for analysis of the intervertebral fusion and incorporation of the intervertebral bone graft and its influence on postoperative re-kyphosing. Twenty-nine patients with acute fractures of the thoracolumbar spine, treated between 1988 and 1995 at the Department of Trauma Surgery, Hannover Medical School, underwent posterior stabilisation and interbody fusion with transpedicular cancellous bone grafting. This study group was followed clinically and radiologically for a mean of 3.5 years. All patients underwent spiral CT scan with sagittal reconstruction after implant removal. Twenty-four type A, four type B, and one type C lesion were posteriorly stabilised and transpedicular intervertebral bone grafting was performed. The operative time averaged 2 h 50 min, the intraoperative fluoroscopy time 4 min 7 s, and the mean intraoperative blood loss was 376 ml. Four patients out of six with an incomplete neurologic lesion (Frankel/ASIA D) improved to Frankel/ASIA grade E. Two complications were observed: one delayed wound healing and one venous thrombosis with secondary pulmonary embolism. Compared to the preoperative status, our follow-up examinations demonstrated permanent social sequelae: the percentage of individuals able to do physical labor was reduced, whereas the proportion of unemployed or retired patients increased. The assessment of complaints and functional outcome with the Hannover Spine Score reflected a significant difference ( P<0.001) between the status before injury (96.6/100 points) and at follow-up (64.4/100 points). The radiographic follow-up revealed a mean loss of correction of 7.8 degrees ( P<0.005). CT scans after implant removal showed an interbody fusion and incorporation of the transpedicular bone graft in ten patients (34%). In another ten patients (34%), the CT scans demonstrated the interbody fusion at the anterior and posterior walls of the vertebral body via direct contact due to collapse of the disc space. In these patients, the bone graft was not incorporated and no central interbody fusion could be found. In nine patients (31%) neither interbody fusion nor incorporation of the transpedicular graft was achieved. A frequent and reliable intervertebral fusion could not be achieved with the described technique of transpedicular bone grafting. The ineffectiveness of the intervertebral graft was found to be a reason for postoperative re-kyphosing.

Imaging glial activation in patients with post-treatment Lyme disease symptoms: a pilot study using [11C]DPA-713 PET

The pathophysiology of post-treatment Lyme disease syndrome (PTLDS) may be linked to overactive immunity including aberrant activity of the brain's resident immune cells, microglia. Here we used [¹¹C]DPA-713 and positron emission tomography to quantify the 18 kDa translocator protein, a marker of activated microglia or reactive astrocytes, in the brains of patients with post-treatment Lyme disease symptoms of any duration compared to healthy controls. Genotyping for the TSPO rs6971 polymorphism was completed, and individuals with the rare, low affinity binding genotype were excluded. Data from eight brain regions demonstrated higher [¹¹C]DPA-713 binding in 12 patients relative to 19 controls. [¹¹C]DPA-713 PET is a promising tool to study cerebral glial activation in PTLDS and its link to cognitive symptoms.

Improved control of image optical density with low-dose digital and conventional radiography in bedside imaging

The technical and diagnostic performance of simultaneously acquired low-dose (44% of standard dose) storage-phosphor digital radiographs (system resolution = 0.2 mm, 10 bits) were compared with those of standard-dose conventional bedside radiographs of the chest in 32 patients. The mean optical density (OD) of the lungs (800 measurements) was closer to the ideal density with digital radiography (1.45 OD +/- 0.20 [standard deviation] vs 1.75 OD +/- 0.53) and was less often outside the usable range (2.5% vs 42.5%). Receiver operating characteristic analysis for detection of simulated nodules and monitoring devices (nine readers, 4,608 observations) showed that digital radiography was superior to conventional radiography (P less than .05) for four of the nine readers and equivalent to conventional radiography for five readers. The authors concluded that digital radiography produces more consistent and ideal image density and performs at least as well as conventional radiography under phantom test conditions.

Hibernoma

Hibernoma is a rare, benign soft tissue tumor composed of brown fat. A 42-year-old white man presented with an enlarging soft tissue mass located in his left medial thigh. This was evaluated radiographically by CT as well as MR imaging. An open biopsy revealed a hibernoma. The mass was subsequently excised in its entirety, maintaining a cuff of normal tissue. The patient has done very well postoperatively. Although nearly 100 cases have been reported, this case is presented to review the clinical and pathological presentation of this tumor and to describe its MR imaging characteristics.

Chemoocclusion vs chemoperfusion for treatment of advanced hepatocellular carcinoma: a randomised trial

AIMS

Transarterial chemoembolization (TACE) can be associated with considerable toxicity and treatment-associated mortality. Transient transarterial chemoocclusion (TACO) using degradable starch microspheres (DSM) has been proposed as a potentially safer alternative while maintaining anti-tumour efficiency. In a randomised phase II trial TACO was compared to transarterial chemoperfusion without DSM (TACP).

METHODS

Seventy-four patients with advanced HCC were randomised to two treatment arms: (i) TACO (600-1200 mg DSM) and (ii) TACP. In both arms regional chemotherapy consisted of cisplatin (100 mg/m2) and doxorubicin (60 mg/m2). Both arms were corresponding in terms of age, gender, liver performance state, and tumour-stage. A maximum of six treatment cycles was applied in monthly intervals. Follow-up was performed in terms of tumour response, time to progression, survival and quality of life.

RESULTS

Tumour response rates did not differ significantly between the two treatment arms, however, there was a tendency towards higher response rates in the TACO arm (TACO vs TACP): partial response: 26 vs 9%, stable disease: 41 vs 55%, progressive disease: 33 vs 36%. Time to tumour progression (32 vs 27 weeks), and overall survival (60 vs 69 weeks) were not significantly different. Grade 4 adverse events were rare in both arms and treatment-associated mortality was not observed. In addition, there was no significant difference in terms of quality of life under therapy (EORTC).

CONCLUSION

TACO with DSM did not improve response or survival significantly compared to TACP in advanced non-resectable HCC.

Biodistribution and Radiation Dosimetry of 124I-DPA-713, a PET Radiotracer for Macrophage-Associated Inflammation

Whole-body PET/CT was performed using 124I-DPA-713, a radioligand for the 18-kDa translocator protein (TSPO), to determine biodistribution and radiation dosimetry. Methods: Healthy subjects aged 18-65 y underwent whole-body PET/CT either at 4, 24, and 48 h or at 24, 48, and 72 h after intravenous injection of 124I-DPA-713. Time-activity curves were generated and used to calculate organ time-integrated activity coefficients for each subject. The resulting time-integrated activity coefficients provided input data for calculation of organ absorbed doses and effective dose for each subject using OLINDA. Subjects were genotyped for the TSPO polymorphism rs6971, and plasma protein binding of 124I-DPA-713 was measured. Results: Three male and 3 female adults with a mean age of 40 ± 19 y were imaged. The mean administered activity and mass were 70.5 ± 5.1 MBq (range, 62.4-78.1 MBq) and 469 ± 34 ng (range, 416-520 ng), respectively. There were no adverse or clinically detectable pharmacologic effects in any of the 6 subjects. No changes in vital signs, laboratory values, or electrocardiograms were observed. 124I-DPA-713 cleared rapidly (4 h after injection) from the lungs, with hepatic elimination and localization to the gastrointestinal tract. The mean effective dose over the 6 subjects was 0.459 ± 0.127 mSv/MBq, with the liver being the dose-limiting organ (0.924 ± 0.501 mGy/MBq). The percentage of free radiotracer in blood was approximately 30% at 30 and 60 min after injection. Conclusion:124I-DPA-713 clears rapidly from the lungs, with predominantly hepatic elimination, and is safe and well tolerated in healthy adults.

Storage phosphor versus screen-film radiography: effect of varying exposure parameters and unsharp mask filtering on the detectability of cortical bone defects

Diagnostic performance with storage phosphor radiography is influenced by exposure parameters and digital filtering algorithms. The authors compared the detectability of cortical lesions in excised human femoral shafts on state-of-the-art screen-film radiographs and storage phosphor digital radiographs. For the digital system, the effect of varying exposure parameters (photon flux and tube voltage) and unsharp mask filtering (kernel size and enhancement factor) was tested. Analysis of receiver operating characteristics was performed for 10,560 observations made by eight radiologists. Under identical exposure conditions, storage phosphor imaging yielded no significant advantages over conventional screen-film radiography. Although large variations in exposure dose are possible with storage phosphors, the potential for dose reduction was limited even by means of an increase in tube voltage. The performance with unsharp masked images declined with decreasing kernel size and pronounced enhancement.

The distribution of the alpha7 nicotinic acetylcholine receptor in healthy aging: An in vivo positron emission tomography study with [18F]ASEM

Altered function of the alpha7 nicotinic acetylcholine receptor (α7-nAChR) is implicated in several neuropsychiatric diseases. Nevertheless, studies of the human cerebral α7-nAChR even in healthy aging are limited in number and to postmortem tissue.

METHODS

The distribution of the cerebral α7-nAChR was estimated in nine brain regions in 25 healthy volunteers (ages 21-86 years; median 57 years, interquartile range 52 years) using [18F]ASEM with positron emission tomography (PET) imaging. Regional total distribution volume (VT) measurements were calculated using the Logan method from each subject's 90 min dynamic PET data and their metabolite-corrected plasma input function. Spearman's rank or Pearson's correlation analysis was used depending on the normality of the data. Correlation between age and regional 1) volume relative to intracranial volume (volume ratio) and 2) [18F]ASEM VT was tested. Correlation between regional volume ratio and [18F]ASEM VT was also evaluated. Finally, the relationship between [18F]ASEM VT and neuropsychological measures was investigated in a subpopulation of 15 elderly healthy participants (those 50 years of age and older). Bonferroni correction for multiple comparisons was applied to statistical analyses.

RESULTS

A negative correlation between tissue volume ratio and age was observed in six of the nine brain regions including striatum and five cortical (temporal, occipital, cingulate, frontal, or parietal) regions. A positive correlation between [18F]ASEM VT and age was observed in all nine brain regions of interest (ROIs). There was no correlation between [18F]ASEM VT and volume ratio in any ROI after controlling for age. Regional [18F]ASEM VT and neuropsychological performance on each of eight representative subtests were not correlated among the well-performing subpopulation of elderly healthy participants.

CONCLUSIONS

Our results suggest an increase in cerebral α7-nAChR distribution over the course of healthy aging that should be tested in future longitudinal studies. The preservation of the α7-nAChR in the aging human brain supports the development of therapeutic agents that target this receptor for use in the elderly. Further study of the relationship between α7-nAChR availability and cognitive impairment over aging is needed.

High Availability of the α7-Nicotinic Acetylcholine Receptor in Brains of Individuals with Mild Cognitive Impairment: A Pilot Study Using 18F-ASEM PET

Emerging evidence supports a hypothesized role for the α7-nicotinic acetylcholine receptor (α7-nAChR) in the pathophysiology of Alzheimer's disease. 18F-ASEM (3-(1,4-diazabicyclo[3.2.2]nonan-4-yl)-6-18F-fluorodibenzo[b,d]thiophene 5,5-dioxide) is a radioligand for estimating the availability of α7-nAChR in the brain in vivo with PET. Methods: In this cross-sectional study, 14 patients with mild cognitive impairment (MCI), a prodromal stage to dementia, and 17 cognitively intact, elderly controls completed 18F-ASEM PET. For each participant, binding in each region of interest was estimated using Logan graphical analysis with a metabolite-corrected arterial input function. Results: Higher 18F-ASEM binding was observed in MCI patients than in controls across all regions, supporting higher availability of α7-nAChR in MCI. 18F-ASEM binding was not associated with verbal memory in this small MCI sample. Conclusion: These data support use of 18F-ASEM PET to examine further the relationship between α7-nAChR availability and MCI.

"Single-exposure" dual energy digital radiography in the detection of pulmonary nodules and calcifications

We studied the detectability of mineralized and non-mineralized simulated pulmonary nodules with dual energy digital radiography. "Soft tissue" and "bone" images (pixel size = 0.2 mm, 10 bits deep) were obtained with subtraction image processing after a single simultaneous exposure (100 kVp, 8 mAs, 17 mR skin exposure dose) of two storage phosphors with an interleaved 0.9 mm copper wafer. Three classes of paraffin-based nodules (0.5 to 3.0 cm) of varying mineral concentration (0, 120 and 190 mg/cm3 K2HPO4) were randomly positioned on the chest wall of two healthy volunteers to simulate calcified and non-calcified nodules. The average receiver operating characteristics (ROC) area of six readers (n = 2880 observations) showed that digital "bone" images (ROC area: 0.77 +/- 0.03) were significantly better (P less than 0.04) than conventional radiographs (OC Film, Lanex medium screens, 141 kVp, 19 mR skin exposure dose) (ROC area: 0.71 +/- 0.05) in detecting calcification in nodules. The unsubtracted digital images of lower kilovoltage were not superior to the 141 kVp conventional radiographs in a subgroup of two readers (ROC area: 0.73 +/- 0.02). Digital "soft tissue" images were equivalent to conventional chest radiographs in detecting soft tissue pulmonary nodules (ROC areas: 0.92 +/- 0.04 and 0.92 +/- 0.05, respectively.

Initiation and perpetuation of rat adjuvant arthritis is inhibited by the anti-CD2 monoclonal antibody (mAb) OX34

OBJECTIVE

The purpose of this study was to investigate the therapeutic potential of the anti-CD2 mAb OX34 first with regard to bone protection in established rat adjuvant arthritis (AA) and secondly with regard to prevention of AA induction.

METHODS

Established AA was treated with dexamethasone (1 mg/kg body weight) for two days plus OX34 mAb or control mAb over three days (2 mg and then 1 mg) starting at different time points of the disease. For prevention studies animals were injected as above with mAb before induction of AA. Arthritis score (AS), hindpaw thickness, and body weight were blindly measured three times per week. Flow cytometry and hindpaw radiography were performed at the end of the study (day 29).

RESULTS

Treatment of early AA with OX34 mAb combined with dexamethasone but not dexamethasone plus control mAb dramatically suppressed established AA as assessed by AS and hind paw thickness (> 65% and > 80% reduction, respectively; p < 0.05). Most importantly, early treatment in the course of AA almost completely prevented bone destruction in established AA. When given before AA induction OX34 alone prevented the initiation of arthritis compared with controls (AS reduction 83-95%, p < 0.05). In addition, OX34 plus dexamethasone treatment resulted in depletion of CD4+ T cells but not CD8+ T cells. IL2R+ and CD45RC- ('memory') T cells were significantly reduced.

CONCLUSIONS

Anti-CD2 mAb treatment prevents AA induction confirming the role of CD4+ T cells in the induction phase of AA. In addition, early OX34 plus dexamethasone treatment resulted in pronounced clinical improvement and joint protection. OX34 treatment therefore inhibits the initiation and the perpetuation of rat AA.

Cerebrospinal fluid derived from progressive multiple sclerosis patients promotes neuronal and oligodendroglial differentiation of human neural precursor cells in vitro

In the adult CNS, tissue-specific germinal niches, such as the subventricular zone of the lateral ventricles and the subgranular zone of the dentate gyrus of the hippocampus, contain multipotent neural precursor cells (NPCs) with the capacity to self-renew and differentiate into functional brain cells (i.e. neurons, astrocytes or oligodendrocytes). Due to their intrinsic plasticity, NPCs can be considered an essential part of the cellular mechanism(s) by which the CNS tries to repair itself after an injury. In inflammatory CNS disorders, such as multiple sclerosis (MS), neurogenesis and gliogenesis occur as part of an 'intrinsic' self-repair process. However, full and long-lasting repair in progressive MS is not achieved. Recent data suggest that endogenous NPCs, while trying to repair the damaged CNS in MS, may become the target of the disease itself. It is possible that factors produced during MS, like CNS-infiltrating blood-borne inflammatory mononuclear cells, reactive CNS-resident cells, and humoral mediators, can alter the physiological properties of NPCs, ultimately impairing their ability to promote neural regeneration. Here, we investigate the effect of cerebrospinal fluid (CSF) derived from primary progressive (PPMS) and secondary progressive (SPMS) MS patients (CSF-MS) on the survival, proliferation, and differentiation of commercially available human embryonic-derived NPCs named ENStem-A. We found that PPMS derived CSF markedly reduced the proliferation of ENStem-A and increased their differentiation toward neuronal and oligodendroglial cells, compared to control CSF. Similar but less striking results were seen when ENstem-A were treated with SPMS derived CSF. Our findings suggest that in both SPMS and PPMS the CNS milieu, as determined by extrapolation from CSF findings, may stimulate the endogenous pool of NPCs to differentiate into neurons and oligodendrocytes.

Concentration dependent alterations of DNA replication initiation and elongation by benzo[a]pyrene diol epoxide

Vero cells treated with various concentrations of (+/-)7 beta, 8 alpha-dihydroxy-9 alpha, 10 alpha-epoxy, 7,8,9,10-dihydrobenzo[a]pyrene (BP-diol epoxide I) exhibited dose-dependent inhibition in both the rate of DNA synthesis and in the size of nascent DNA. The maximum inhibition was seen 2--3 h after addition of BP-diol epoxide I. A recovery in both the rate of synthesis and size of nascent DNA was observed 5--10 h after treatment. The pH step alkaline elution assay which separates different nascent DNA replication intermediates was used to investigate whether the inhibition and recovery noted above could be accounted for by alterations in DNA replication initiation (DNA synthesis within a replicon) or elongation (rejoining of replicons). At lowest dose studied (0.166 muM BP-diol epoxide I) a reversible inhibition in DNA initiation was observed. At the higher dose levels (0.66 muM and 1.66 muM BP-diol epoxide I) inhibition of both DNA initiation and elongation were observed and inhibition of elongation predominated. The inhibition in elongation was detected by an increase in the relative amount of low molecular weight nascent DNA associated with DNA synthesis within a replicon and a relative decrease in the higher molecular weight elongated DNA. A reversal in the inhibition of both initiation and elongation was noted.

Prostatic cancer. Transcortin levels during treatment with estramustine phosphate

Plasma transcortin and cortisol levels, which are significantly elevated by estrogens, were determinied in a group of patients with prostatic cancer who were on estramustine phosphate (Estracyt) therapy. In a series of 44 male patients studied transcortin and corticol levels became elevated above normal and were maintained at these high levels as long as the patients were on estramustine phosphate therapy. The levels observed in this study may serve as reliable indices to monitor patients who are on this drug.

18F-XTRA PET for Enhanced Imaging of the Extrathalamic α4β2 Nicotinic Acetylcholine Receptor

Reduced density of the α4β2 nicotinic acetylcholine receptor (α4β2-nAChR) in the cortex and hippocampus of the human brain has been reported in aging and patients with neurodegenerative disease. This study assessed the pharmacokinetic behavior of ¹⁸F-(-)-JHU86428 (¹⁸F-XTRA), a new radiotracer for in vivo PET imaging of the α4β2-nAChR, particularly in extrathalamic regions of interest in which the α4β2-nAChR is less densely expressed than in thalamus. ¹⁸F-XTRA was also used to evaluate the α4β2-nAChR in the hippocampus in human aging. Methods: Seventeen healthy nonsmoker adults (11 men, 6 women; age, 30-82 y) underwent PET neuroimaging over 90 or 180 min in a high-resolution research tomograph after bolus injection of ¹⁸F-XTRA. Methods to quantify binding of ¹⁸F-XTRA to the α4β2-nAChR in the human brain were compared, and the relationship between age and binding in the hippocampus was tested. Results: ¹⁸F-XTRA rapidly entered the brain, and time-activity curves peaked within 10 min after injection for extrathalamic regions and at approximately 70 min in the thalamus. The 2-tissue-compartment model (2TCM) predicted the regional time-activity curves better than the 1-tissue-compartment model, and total distribution volume (V_T) was well identified by the 2TCM in all ROIs. V_T values estimated using Logan analysis with metabolite-corrected arterial input were highly correlated with those from the 2TCM in all regions, and values from 90-min scan duration were on average within 5% of those values from 180 min of data. Parametric images of V_T were consistent with the known distribution of the α4β2-nAChR across the brain. Finally, an inverse correlation between V_T in the hippocampus and age was observed. Conclusion: Our results extend support for use of ¹⁸F-XTRA with 90 min of emission scanning in quantitative human neuroimaging of the extrathalamic α4β2-nAChR, including in studies of aging.