Beta-secretase cleavage of Alzheimer's amyloid precursor protein by the transmembrane aspartic protease BACE

Cerebral deposition of amyloid beta peptide (Abeta) is an early and critical feature of Alzheimer's disease. Abeta generation depends on proteolytic cleavage of the amyloid precursor protein (APP) by two unknown proteases: beta-secretase and gamma-secretase. These proteases are prime therapeutic targets. A transmembrane aspartic protease with all the known characteristics of beta-secretase was cloned and characterized. Overexpression of this protease, termed BACE (for beta-site APP-cleaving enzyme) increased the amount of beta-secretase cleavage products, and these were cleaved exactly and only at known beta-secretase positions. Antisense inhibition of endogenous BACE messenger RNA decreased the amount of beta-secretase cleavage products, and purified BACE protein cleaved APP-derived substrates with the same sequence specificity as beta-secretase. Finally, the expression pattern and subcellular localization of BACE were consistent with that expected for beta-secretase. Future development of BACE inhibitors may prove beneficial for the treatment of Alzheimer's disease.

The role of splenic irradiation in treating HIV-associated immune thrombocytopenia

PURPOSE

To evaluate our experience in treating patients with HIV-associated thrombocytopenia using splenic irradiation.

METHODS AND MATERIALS

From 1993 to 1998, 10 patients with HIV-related immune thrombocytopenia (ITP) were treated in our department with low-dose splenic irradiation. All patients had either failed more conventional treatment modalities or possessed some contraindication to them.

RESULTS

Nine of 10 patients had at least a small, transient rise in their platelet counts, but only two received a substantial therapeutic benefit. Of these two, one died shortly after completing his course of radiation therapy while the other maintained near normal platelet counts up to approximately 3(1/2) years following treatment. There were no treatment-related morbidities and one patient was treated twice.

CONCLUSION

While most patients with HIV-associated ITP may initially respond favorably to splenic irradiation with small rises in platelet count, few responses are likely to be sustained or provide clinically significant outcomes. Our results support those previously reported by others treating this same condition. What remains to be investigated is whether there are any prognostic indicators to help identify those patients most likely to respond to this treatment, thus enabling us to reserve splenic irradiation for those who might derive a substantial benefit from it.

Human papillomavirus type 16 E7 DNA vaccine: mutation in the open reading frame of E7 enhances specific cytotoxic T-lymphocyte induction and antitumor activity

A human papillomavirus type 16 E7 DNA vaccine with the open reading frame encoding mutations in two zinc-binding motifs expressed a rapidly degraded E7 protein. This vaccine induced a significantly stronger E7-specific cytotoxic T-lymphocyte response and better tumor protection in mice than did a wild-type E7 DNA vaccine expressing a stable E7 protein.

Reducing unnecessary coagulation testing in hypertensive disorders of pregnancy

OBJECTIVE

To estimate the magnitude of laboratory testing for hypertension in pregnancy and determine whether abnormalities in prothrombin time (PT), activated partial thromboplastin time (aPTT), and fibrinogen can be predicted by results of common, less expensive tests.

MATERIALS AND METHODS

Laboratory records were searched and charts were reviewed to identify gravidas tested for hypertension and to exclude conditions producing coagulopathy. Contingency tables were constructed to assess the ability of the platelet count, lactate dehydrogenase, and transaminases to predict coagulation test results.

RESULTS

Preliminary data on 73 gravidas found that a platelet count plus a lactate dehydrogenase test best predicted coagulation abnormalities. Results on another 732 gravidas indicated that coagulation tests were obtained in about 30%. No patient had a PT greater than 18 seconds, two had an aPTT greater than 40 seconds, and three had fibrinogen levels less than 200 mg/dL. The combination of a normal platelet count plus a normal lactate dehydrogenase had a negative predictive value of 100% for clinically significant abnormalities of PT and aPTT, and 99% for significant abnormalities of fibrinogen.

CONCLUSIONS

Substantial coagulation testing was done on gravidas evaluated for a hypertensive disorder even though the prevalence of clinically significant abnormalities was low. Laboratory evaluation of patients suspected of having preeclampsia need not include a PT, aPTT, or fibrinogen test when there is no evidence of bleeding or of a condition that could produce coagulopathy and when the platelet count and lactate dehydrogenase level are both normal.

Limiting photoreceptor death and deconstruction during experimental retinal detachment: the value of oxygen supplementation

PURPOSE

To assess the role of hypoxia in causing the death and deconstruction of photoreceptors in detached retinas and the effectiveness of supplemental oxygen in limiting such damage.

METHODS

Retinal detachment was induced surgically in the right eye of each of 10 cats. The cats were allowed to survive surgery for 3 days. Two were kept for these 3 days in normoxia (room air, 21% oxygen) and eight in hyperoxia (70% oxygen). The retinas were examined for cell death by use of labels for normal and fragmenting DNA, with antibodies and a cone sheath-specific lectin to demonstrate the status of their inner and outer segments, the synaptic structures of the outer plexiform layer, and the distribution of basic fibroblast growth factor (bFGF) and with in situ hybridization to demonstrate bFGF mRNA.

RESULTS

Retinal detachment without oxygen supplementation caused the death of some photoreceptors; the loss of cytochrome oxidase from the inner segments and the collapse of the outer segments of surviving photoreceptors; the loss of synaptophysin profiles from the outer plexiform layer; and the loss of bFGF protein from retinal neurons and neuroglia but not from retinal vessels. Oxygen supplementation (hyperoxia) during detachment mitigated all these changes, reducing photoreceptor death, maintaining the specialized structures of surviving photoreceptors, and stabilizing the bFGF within the retina.

CONCLUSIONS

In experimental retinal detachment, hypoxia caused by the separation of outer retina from its normal source of nutrients is a factor in inducing the death and deconstruction of photoreceptors as well as in the loss of bFGF from the detached retina. Hyperoxia offered to human patients between diagnosis of retinal detachment and surgery may enhance the function of the reattached retina.

New molecular and epidemiological issues in mesothelioma: role of SV40

Mesotheliomas are malignant tumors usually associated with occupational asbestos exposure. Simian virus 40 (SV40) is a DNA tumor virus that preferentially causes mesotheliomas when injected intracardially and/or intrapleurally into hamsters. SV40 also transforms human cells in tissue culture, and these cells contain extensive DNA damage. In the United States, at least 60% of human mesotheliomas contain and express SV40. In these tumor cells, the SV40 tumor antigen binds and inhibits the cellular tumor suppressors p53 and Rb. These findings suggest that SV40 may contribute to the development of those human mesotheliomas that occur in people not exposed to asbestos. SV40 may also facilitate asbestos-mediated carcinogenicity. The epidemiological data available are insufficient to address the role that SV40 may have played in contributing to the increased incidence of mesothelioma in the second half of this century.

Limiting the proliferation and reactivity of retinal Müller cells during experimental retinal detachment: the value of oxygen supplementation

PURPOSE

To assess the role of hypoxia in inducing the proliferation, hypertrophy, and dysfunction of Muller cells in detached retina and the effectiveness of supplemental oxygen in limiting these reactions.

METHODS

Retinal detachments were produced in the right eye of each of 13 cats; the cats survived surgery for 3 days, during which six were kept in normoxia (room air, 21%) and seven in hyperoxia (70% oxygen). Retinas were labeled for proliferation with an antibody (MIB-1) to a cell cycle protein (Ki-67), for evidence of hypertrophy employing antibodies to the intermediate filament protein glial fibrillary acidic protein (GFAP) and to beta-tubulin and for disturbance of glutamate neurochemistry employing antibodies to glutamate to a glutamate receptor (GluR-2) and to glutamine synthetase.

RESULTS

Results from the two animals kept in normoxia after retinal detachment confirmed previous reports that detachment caused the proliferation of Muller cells, the hypertrophy of Muller cell processes, and the disruption of glutamate recycling by Muller cells. Oxygen supplementation during detachment reduced Muller cell proliferation and hypertrophy and reduced the abnormalities in the distributions of glutamate, GluR-2, and glutamine synthetase.

CONCLUSIONS

Oxygen supplementation reduced the reaction of retinal Muller cells to retinal detachment, limiting their proliferation and helping to maintain their normal structure and function. In the clinical setting, oxygen supplementation between diagnosis and reattachment surgery may reduce the incidence and severity of glial-based complications, such as proliferative vitreoretinopathy.

Gene expression and synthesis of natriuretic peptides by cultured human glomerular cells

BACKGROUND

Atrial natriuretic peptide, brain natriuretic peptide and C-type natriuretic peptide belong to a family of hormones that have natriuretic and vasodepressor activity and may play a pathophysiologic role in hypertension, heart failure and renal failure. Whereas immunoreactive human forms of these three natriuretic peptides are found in renal tubules, it is not clear whether they are derived from the systemic circulation or from local production.

OBJECTIVE

To examine the gene expression of natriuretic peptides in cultured human glomerular cells.

MATERIALS AND METHODS

We sought to determine the presence of messenger RNA encoding for these natriuretic peptides using polymerase chain reaction following reverse transcription. The polymerase chain reaction products were confirmed by direct sequencing. Atrial natriuretic peptide, brain natriuretic peptide and C-type natriuretic peptide in cell-culture supernatants were measured by radioimmunoassays (with detection limits of 2.1, 2.1 and 0.21 pmol/l, respectively).

RESULTS

Atrial natriuretic peptide messenger RNA was not found in mesangial or glomerular epithelial cells (despite stimulation with tumor necrosis factor-alpha) except when the cells were cultured with a high concentration of fetal bovine serum (> 10%). Similarly, this peptide was not detected in supernatant unless the cells were cultured with fetal bovine serum at concentrations of > 10%. Brain natriuretic peptide messenger RNA was readily detected in cultured mesangial and glomerular epithelial cells with a lower concentration in the former. Brain natriuretic peptide was not found in the supernatant of resting mesangial cells but became detectable when incubated with tumor necrosis factor-alpha or fetal bovine serum. C-type natriuretic peptide messenger RNA was detected in mesangial and glomerular epithelial cells with a higher concentration in the latter. C-type natriuretic peptide was detected in the supernatant of resting glomerular epithelial cells and levels rose when incubated with increasing concentrations of tumor necrosis factor-alpha or fetal bovine serum. However, C-type natriuretic peptide was not detected in the supernatant of resting mesangial cells and remained undetectable following incubation with tumor necrosis factor-alpha or fetal bovine serum.

CONCLUSION

Our results suggest differences in the synthesis of natriuretic peptides between glomerular mesangial and epithelial cells.

Subgroups of frequent users of an inpatient mental health program at a community hospital in Canada

OBJECTIVE

The study examined demographic and clinical characteristics of frequent users of mental health services at a large community hospital in an urban-suburban area in Canada to identify subgroups within this patient population.

METHODS

Patients who had had three or more inpatient admissions over any 12-month period between January 1, 1993, and December 31, 1995, were included in the study. Medical records were reviewed to collect summary data on 23 variables encompassing demographic characteristics and admission and discharge information. Quick cluster analysis was performed to identify subgroups within the frequent-user population. Chi square tests and analysis of variance were used to analyze group differences between clusters.

RESULTS

Three patient subgroups accounted for 67 of the 83 patients (80.7 percent) identified as frequent users. Admission patterns were the strongest predictors of subgroup differences.

CONCLUSIONS

Identifying subgroups within the frequent-user population may help in developing appropriate treatment and discharge plans with the aim of reducing the need for frequent utilization of inpatient mental health services.

Spontaneous conversion and maintenance of sinus rhythm by amiodarone in patients with heart failure and atrial fibrillation: observations from the veterans affairs congestive heart failure survival trial of antiarrhythmic therapy (CHF-STAT). The Department of Veterans Affairs CHF-STAT Investigators

BACKGROUND

In a multicenter, double-blind, placebo-controlled study, the long-term effects of amiodarone on morbidity and mortality in patients with congestive heart failure (CHF) and atrial fibrillation (AF) were evaluated during a 4-year period.

METHODS AND RESULTS

Of 667 patients with CHF, 103 (15%) had AF at baseline. Of these, 51 were randomized to amiodarone and 52 to placebo. The group with sinus rhythm and the group in AF were comparable except for a higher proportion of AF in patients with nonischemic versus ischemic cardiomyopathy (41% versus 27%, P<0.005). The mean ventricular response (VR) during AF over 24 hours was reduced by amiodarone at 2 weeks (20%, P=0.001), at 6 months (18%, P=0.001), and at 12 months (16%, P=0.006). Maximal VR was reduced 22% (P=0.001) at 2 weeks, 19% (P=0.001) at 6 months, and 14% (P=0.001) at 12 months. Sixteen of 51 patients on amiodarone and 4 of 52 on placebo converted to sinus rhythm during the study (chi2=9.23, P=0.002). During follow-up, 11 of 268 patients in sinus rhythm on amiodarone at baseline and 22 of the 263 in sinus rhythm on placebo developed AF; the difference was significant (chi2=12.88, P=0.005). Analysis of total mortality during follow-up showed a significantly lower mortality rate (P=0. 04) in patients in AF at baseline who subsequently converted to sinus rhythm on amiodarone than in those who did not convert to sinus rhythm on the drug.

CONCLUSIONS

In patients with CHF, amiodarone has a significant potential to spontaneously convert patients in AF to sinus rhythm, with patients who convert having a lower mortality rate than those who do not. The drug prevented the development of new-onset AF and significantly reduced the VR in those with persistent AF.

Effects of short heat exposure on human red and white blood cells

BACKGROUND

The infusion of warm intravenous fluid (IVF) is a simple and effective method used to maintain or restore core body temperature. At present, 40 degrees C is believed to be the highest temperature that can be safely administered. There is concern that temperatures greater than 40 degrees C may harm blood cells. The mixing time of IVF infused into a high-flow vein such as the superior vena cava is very short, however, approximately 300 milliseconds. We will determine the maximum temperature and exposure time tolerated by human red and white blood cells without producing injury.

METHODS

Whole blood and isolated neutrophils were exposed to temperatures (40-80 degrees C) for short time intervals (150-1,200 milliseconds). Lethal injury to red and white blood cells was measured by the plasma free hemoglobin and percent viability, respectively. Neutrophil viability was measured by trypan blue staining. Sublethal injury to red and white cells was measured by osmotic fragility and oxidative burst, respectively. Neutrophil oxidative burst was measured by chemiluminescence. Control values were compared with postexposure values using analysis of variance with p < 0.05 indicating significance.

RESULTS

Lethal injury to red blood cells did not occur until exposure at 70 degrees C for 300 milliseconds (plasma free hemoglobin, 116.3 +/- 34.7 mg%; p < 0.05). Lethal injury to neutrophils did not occur, even at exposure at 80 degrees C for 1,200 milliseconds. Sublethal injury to red blood cells did not occur until exposure at 60 degrees C for 1,200 milliseconds. Sublethal injury to neutrophils did not occur until exposure at 60 degrees C for 600 milliseconds (percent change in oxidative burst = 28.9 +/- 0.96%; p < 0.05).

CONCLUSIONS

The exposure of human red blood cells and neutrophils to temperatures up to 60 degrees C for up to 600 milliseconds does not cause lethal or sublethal injury. These findings contribute to the body of evidence supporting the use of centrally infused IVF at temperatures greater than 40 degrees C for active core rewarming.

Prototype Internet consultation system for radiologists

The overall purpose of this study is to develop a prototype radiological consultation system. We concentrate our work on prototype software environment for the system. The system provides a second diagnostic opinion based on similar cases, incorporating the experience of radiologists, their diagnostic rules and a database of previous cases. The system allows a radiologist to enter the description of a particular case using the lexicon such as BI-RADS of American College of Radiology and retrieve the second diagnostic opinion (probable diagnosis) for a given case. The system also allows a radiologist to get other important information too. These advances are based on a new computational intelligence technique and first-order logic. We implemented a rule-based prototype diagnostic system. Two experimental Internet versions are currently available on the web and are under testing and evaluation of design. The diagnosis is based on the opinions of radiologists in combination with the statistically significant diagnostic rules extracted from the available database.

Iodine-131 anti-B1 antibody for B-cell lymphoma: an update on the Michigan Phase I experience

Iodine-131 anti-B1 antibody radioimmunotherapy for B-cell lymphoma was previously reported to have substantial antitumor activity in B-cell non-Hodgkin's lymphoma (NHL) after failures of standard and salvage chemotherapy. In this article, the University of Michigan Phase I clinical experience is updated, with follow-up of up to 6 yr since initial treatment reported.

METHODS

Thirty-four patients with CD20-expressing NHL were first studied with one or more dosimetric doses of approximately 5 mCi of 1311 anti-B1 antibody (after varying predoses of unlabeled anti-B1 antibody). They were then treated with a patient-specific radioimmunotherapeutic dose designed to deliver a specified radiation dose to the whole body of between 25 and 85 cGy. Patients were observed for toxicity and tumor response.

RESULTS

Seventeen (50%) patients had low-grade NHL, 9 (26%) had low-grade transformed NHL and 8 (24%) had de novo intermediate-grade NHL. At study entry, 17 (50%) had an elevated lactate dehydrogenase level, 12 (35%) had high tumor burden and 18 (53%) had not responded to their last chemotherapy. The median number of prior NHL therapies was 4.1. Twenty-eight of 34 patients completed treatment, with 22 of 28 (79%) achieving a response and 14 of 28 (50%) achieving a complete response (CR). The median duration of response was 357 days. The median duration of response for CRs was 471 days, with 4 CRs having a duration of > 1000 days (maximum = > 1460 days). Bone marrow toxicity was dose-limiting and dependent on the total-body dose (TBD) of radiation. Thrombocytopenia appeared to be more marked in patients with prior bone marrow transplantation. The TBD of 75 cGy was established as the maximum tolerated dose in patients who had not had prior bone marrow transplantation. Duration of CR was significantly longer (p < 0.04) in patients who received a TBD of 65-75 cGy (1109 days) than it was in those who received a lower TBD of 25-60 cGy (385 days). Four of 34 (12%) patients developed detectable human antimouse antibody levels. The median survival from study entry for all patients was 1508 days (range = 63 to >2226 days). Sixteen of 17 patients who achieved a response of > or = 6 mo duration remain alive.

CONCLUSION

This update of the Phase I results after 1311 anti-B1 antibody treatment for NHL indicates that CRs can be durable and that survival can be of long duration. This form of therapy for NHL should have increasing application in clinical practice after confirmation of these results in larger multicenter studies.

HLA-G isoforms produced by placental cytotrophoblasts and found in amniotic fluid are due to unusual glycosylation

The human placenta expresses HLA-G, a nonclassical (class Ib) MHC molecule that could play a central role in maternal tolerance of the semiallogeneic fetus. In this work, we report the production of a new mAb, 4H84, that specifically reacts with HLA-G in two formats: immunocytochemistry and immunoblotting. Immunolocalization experiments with 4H84 confirmed our previous finding that cytotrophoblasts within the uterine wall are the only cells in tissue sections of placenta that express the HLA-G protein. Additional experiments showed that both amniocytes and cytotrophoblasts in the amnion-chorion express this protein. Since multiple HLA-G transcripts have been described, we used immunoblotting to study the HLA-G isoforms produced by cytotrophoblasts in vitro and by the amnion-chorion in vivo. Cytotrophoblasts, their conditioned medium, and amniotic fluid samples contained heterodisperse immunoreactive bands (Mr 35,000-50,000). N-deglycosylation by peptide-N-glycosidase F digestion resolved these isoforms into two distinct bands. Cell samples contained primarily an Mr 37,000-42,000 protein, most likely encoded by the full-length mRNA. Conditioned medium and amniotic fluid contained a slightly smaller protein, most likely the secreted form lacking the transmembrane and cytoplasmic regions. Removal of polylactosamine chains by endo-beta D-galactosidase digestion significantly reduced the electrophoretic mobility of the immunoreactive bands, suggesting that HLA-G, unlike class Ib molecules studied to date, carries N-acetyllactosamine units. These data show that Mr heterogeneity of HLA-G is due to its novel glycosylation, rather than to the translation of alternatively spliced mRNAs. We postulate that the unusual carbohydrate structures this molecule carries could interact with maternal immune cells and/or stabilize the molecule.

Complementary expression of HIP, a cell-surface heparan sulfate binding protein, and perlecan at the human fetal-maternal interface

The human hemochorial placenta is a structure formed by the invasion of cytotrophoblasts into the uterus. Previous studies from our laboratory have demonstrated a role for heparan sulfate proteoglycans (HSPGs) and their binding proteins in interactions between human trophoblastic and uterine cell lines in vitro. In this study, expression of both mRNA and protein of a novel, cell surface, heparin/heparan sulfate interacting protein (HIP), by human trophoblastic cell lines-i.e., JAR, JEG, and BeWo-and by human cytotrophoblast was examined throughout gestation. Immunohistochemistry of the human fetal-maternal interface demonstrated abundant HIP expression in cytotrophoblast cells, with lesser staining in syncytiotrophoblast and little or no staining in surrounding stromal or decidual cells. Staining with antibodies to the basement membrane HSPG, perlecan, demonstrated a pattern of staining complementary to that of HIP. Cytotrophoblasts in the uterine stroma, not affiliated with attached villi, displayed a less intense deposition of perlecan. In vitro binding studies of 125I-perlecan to a 17-amino acid synthetic peptide sequence of HIP, which has a high affinity and specificity for heparin/heparan sulfate, indicates that perlecan binds to the HIP peptide with high affinity (KDapp = 0.6 nM) and in a heparin-inhibitable manner. Furthermore, HIP antibodies inhibited by 61-88% in vitro invasion by trophoblasts in assays using primary cultures of normal human cytotrophoblasts. Consistent with this was the observation that immunohistochemically detectable HIP expression was greatly reduced in pre-eclamptic cytotrophoblasts, a condition in which trophoblast invasion is abnormally shallow. It is suggested that HIP potentiates human cytotrophoblast interactions with HSPGs, in vivo, and facilitates trophoblast invasion processes.

Home intravenous antibiotic treatment for febrile episodes in immune-compromised pediatric patients

The purpose of this work was to assess the feasibility of home intravenous antibiotic treatment (HIAT) for febrile episodes in immune-compromised (neutropenic, splenectomized), low-risk pediatric patients. Thirty hematology-oncology patients who presented to our emergency room from January 1993 to January 1995 and who suffered from a febrile episode and were considered at low risk for septic complications were immediately discharged on HIAT. Patients were followed for at least 3 weeks after recovery. Patients and parents were retrospectively questioned about adverse effects and about their degree of satisfaction with home treatment. Patients who required hospitalization during this period were considered unresponsive to HIAT and were analyzed for causes and adverse effects. Thirteen out of 60 (22%) febrile episodes, or eight out of 42 (19%) episodes of fever and neutropenia eventually led to hospitalization. Pseudomonas species infections were associated with the highest rate of unresponsiveness (88%). A central venous catheter infection developed in two cases following HIAT (two cases out of 640 days of therapy). No other complications were identified. No infection-related morbidity was observed. Patients and parents were highly satisfied with HIAT and wanted to use it again, if necessary. Immediate discharge on HIAT for low-risk pediatric immune-compromised patients suffering from a febrile episode is feasible, safe, and well accepted by patients and families. Patients who are found to have Pseudomonas infections should probably be hospitalized. Our results are preliminary and must be confirmed by a prospective, randomized trial before definite recommendations can be made.

Differential regulation of chordin expression domains in mutant zebrafish

Patterning along the dorsal-ventral (D-V) axis of Xenopus and Drosophila embryos is believed to occur through a conserved molecular mechanism, with homologous proteins Chordin and Short gastrulation (Sog) antagonizing signaling by bone morphogenetic protein 4 (BMP-4) and Decapentaplegic (Dpp), respectively. We have isolated a zebrafish gene that is highly homologous to chordin and sog within cysteine-rich domains and exhibits conserved aspects of expression and function. As in Xenopus embryos, zebrafish chordin is expressed in the organizer region and transiently in axial mesoderm. Injection of zebrafish chordin mRNA to the ventral side of Xenopus embryos induced secondary axes. Ectopic overexpression in zebrafish resulted in an expansion of paraxial mesoderm and neurectoderm at the expense of more lateral and ventral derivatives, producing a range of defects similar to those of dorsalized zebrafish mutants (Mullins et al., 1996). In accordance with the proposed function of chordin in D-V patterning, dorsalized zebrafish mutants showed expanded domains of chordin expression by midgastrulation, while some ventralized mutants had reduced expression; however, in all mutants examined, early organizer expression was unaltered. In contrast to Xenopus, zebrafish chordin is also expressed in paraxial mesoderm and ectoderm and in localized regions of the developing brain, suggesting that there are additional roles for chordin in zebrafish embryonic development. Surprisingly, paraxial mesodermal expression of chordin appeared unaltered in spadetail mutants that later lack trunk muscle (Kimmel et al., 1989), while axial mesodermal expression was affected. This finding reveals an unexpected function for spadetail in midline mesoderm and in differential regulation of chordin expression during gastrulation.

Differences in risk of Crohn's disease in offspring of mothers and fathers with inflammatory bowel disease

OBJECTIVE

To determine whether there are any unusual patterns of transmission of susceptibility to inflammatory bowel disease (IBD) within multiplex families.

METHODS

Individuals with IBD were recruited for genome-wide screening of susceptibility genes. The extent of familial aggregation and blood relationships in multiplex families were determined by questionnaires given to participants followed up by confirmation of disease diagnosis by participants' physicians.

RESULTS

Of 135 families identified in which both a parent and a child had IBD, 93 involved transmission of susceptibility to disease from mother to child versus 42 examples of transmission from father to child (p = 0.00001, exact two-tailed binomial test). This distortion in transmission on the basis of the sex of the parent was observed only among non-Jewish pairs with Crohn's disease (CD), in which, of 33 parent-child pairs with CD, disease susceptibility was transmitted from the mother 28 times (p = 0.00007).

CONCLUSION

Susceptibility to CD in a subset of patients may involve a gene that is imprinted.

Whole-abdomen radiation therapy as salvage treatment for epithelial ovarian carcinoma

PURPOSE

This study aimed to evaluate the efficacy and safety of whole-abdomen radiation therapy as salvage treatment in patients with ovarian cancer.

PATIENTS AND METHODS

Twenty-seven patients who failed aggressive cytoreductive surgery followed by multiple-drug platinum-based chemotherapy were found to have recurrent epithelial carcinoma of the ovary and were treated with whole-abdomen radiation as salvage therapy. Dosage fractions were planned at 100 to 150 cGy daily to 3000 to 3500 cGy, followed by a pelvic boost at 150 to 180 cGy daily. All patients completed the planned treatment. The average treatment program required 53.5 days (range, 42-71 days).

RESULTS

Survival rates at years 1 through 5 were 66%, 48%, 26%, 15%, and 15%, respectively. Residual disease at initiation of radiation correlated strongly with length of survival. The patients with microscopic disease survived an average of 63 months (range, 30-111 months). Patients with disease larger than 2 cm survived an average of 9 months (range, 5-17 months). Toxicity was seen in all patients. Eight patients experienced grade 3 or 4 toxicity, primarily white blood cell count and gastrointestinal toxicity. There were no deaths related to toxicity.

DISCUSSION

This experience strongly suggests that whole-abdomen radiation is a viable salvage option, especially for patients with microscopic retroperitoneal disease or small-volume macroscopic disease.

Uptake of 2-deoxy-2-[18F]fluoro-D-glucose in the normal testis: retrospective PET study and animal experiment

Our retrospective PET and animal studies were conducted on a total of eight patients with normal testes and five male Sprague-Dawley rats. All the rats were necropsied at 60 minute post-injection of FDG, and the organs were removed and counted. The human tests were visualized on 60-70 minute FDG-PET images and whole- or partial-body images in all of the patients. The correlations between patient age over 50 years old and testis-to-muscle ratios, and patient age and SUVs were statistically significant, r = -0.755, p < 10(-6)(n = 7), r = -0.900, p < 0.007 (n = 4), respectively. FDG uptake of the rat tests was 0.162 +/- 0.004% kg injected dose/g (n = 5). The uptake was approximately 6.0 and 3.6 times as high as muscle and blood levels, respectively. In conclusion, there is substantial uptake of FDG into the normal testis which declines with age. The normal levels of FDG uptake in the testis relative to the patient's age should be considered in the interpretation of FDG scans of the inguinal and lower pelvic regions.