SETD2 loss-of-function promotes renal cancer branched evolution through replication stress and impaired DNA repair

Defining mechanisms that generate intratumour heterogeneity and branched evolution may inspire novel therapeutic approaches to limit tumour diversity and adaptation. SETD2 (Su(var), Enhancer of zeste, Trithorax-domain containing 2) trimethylates histone-3 lysine-36 (H3K36me3) at sites of active transcription and is mutated in diverse tumour types, including clear cell renal carcinomas (ccRCCs). Distinct SETD2 mutations have been identified in spatially separated regions in ccRCC, indicative of intratumour heterogeneity. In this study, we have addressed the consequences of SETD2 loss-of-function through an integrated bioinformatics and functional genomics approach. We find that bi-allelic SETD2 aberrations are not associated with microsatellite instability in ccRCC. SETD2 depletion in ccRCC cells revealed aberrant and reduced nucleosome compaction and chromatin association of the key replication proteins minichromosome maintenance complex component (MCM7) and DNA polymerase δ hindering replication fork progression, and failure to load lens epithelium-derived growth factor and the Rad51 homologous recombination repair factor at DNA breaks. Consistent with these data, we observe chromosomal breakpoint locations are biased away from H3K36me3 sites in SETD2 wild-type ccRCCs relative to tumours with bi-allelic SETD2 aberrations and that H3K36me3-negative ccRCCs display elevated DNA damage in vivo. These data suggest a role for SETD2 in maintaining genome integrity through nucleosome stabilization, suppression of replication stress and the coordination of DNA repair.

Genetic analysis of bacteriophage P4 using P4-plasmid ColE1 hybrids

A set of plasmids that contain fragments of the bacteriophage P4 genome has been constructed by deleting portions of a P4-ColE1 hybrid. A P4 genetic map has been established and related to the physical map by examining the ability of these plasmids to rescue various P4 mutations. The P4 virl mutation and P4 genes involved in DNA replication (alpha), activation of P2 helper genes (delta and epsilon), polarity suppression (psu) and head size determination (sid) have been mapped, as has the region responsible for synthesis of a nonessential P4 protein. One of the deleted plasmids contains only 5900 base pairs (52%) of P4 but will form plaques if additional DNA is added to increase its total size to near that of P4. This plasmid is also unique in that it will not form stable associations with P2 lysogens of E. coli which are recA+. P4 alpha mutants can be suppressed as a result of replication under control of the ColE1 part of the hybrid.

Human T-cell lymphotropic virus type I (HTLV-I)-associated adult T-cell leukemia-lymphoma in a patient infected with human immunodeficiency virus type 1 (HIV-1)

A patient had adult T-cell leukemia-lymphoma in the unusual setting of coinfection with human immunodeficiency virus type 1 (HIV-1) and human T-cell lymphotropic virus type I (HTLV-I). The leukemic cells were CD4 positive and showed clonal genetic rearrangement of the T-cell receptor complex. Cytogenetic analysis showed three clonal karyotypic abnormalities: trisomy 3 and two translocations [t(1;15), (X;1)]. The patient was seropositive for HIV and HTLV-I; HTLV-I and HIV-1 DNA sequences were detected in peripheral blood leukocytes by the polymerase chain reaction. The HTLV-I sequences were detected in a relatively high proportion of mononuclear cells (at least 1 in 30 cells), whereas HIV-1 sequences were detected in a smaller proportion of cells (at least 1 in 3000 cells). Clinical remission was achieved after chemotherapy. There was a decrease in the proportion of HTLV-I positive mononuclear cells (at least 1 in 1000 cells), whereas the proportion of HIV-1 positive cells was relatively unchanged (at least 1 in 1000 cells). Adult T-cell leukemia-lymphoma in the setting of HIV coinfection may become increasingly common because asymptomatic retroviral coinfections are frequent.

Usefulness of coronary stenting for cardiogenic shock

Coronary stenting was performed in 15 selected patients with cardiogenic shock, with favorable clinical and angiographic outcomes. This experience suggests that coronary stenting may play an important adjunctive role in the management of cardiogenic shock and may improve outcome beyond that achieved with balloon angioplasty alone.

Molecular cloning and preliminary genetic analysis of the men gene cluster of Bacillus subtilis

The Bacillus subtilis chromosomal locus that contains the genes encoding the menaquinone biosynthetic enzymes (the men genes) was cloned by using an integrable plasmid vector. The men cluster was reconstituted on three overlapping recombinant plasmids, and a tentative gene order was derived. Evaluations of the direction of transcription and of transcriptional boundaries suggested that the men genes are expressed in the form of at least one polycistronic message. In addition, a spectrum of Men phenotypes resulting from the integration of different internal fragments of the cluster indicate transcriptional complexities, possibly including an internal promoter. The size of cloned DNA fragments required to encompass the transcription unit, as well as the locations of known men mutations within these fragments, suggests that a gene(s) not previously identified with the men system is also located within the cluster. The cloned men sequences make available probes to examine the patterns of transcription from the men locus in response to changing environmental conditions and during the developmental sequence represented by endospore formation.

Variable contribution of monoclonal antibodies to ADCC in patients with chronic lymphocytic leukemia

Monoclonal antibodies (mAbs) are increasingly used in treatment protocols for chronic lymphocytic leukemia (CLL). Here we determined (i) the extent of antibody-dependent cellular cytotoxicity (ADCC) of four different mAbs against primary CLL cells, (ii) whether ADCC correlates with antigen density on CLL cells, and (iii) whether allogeneic natural killer (NK) cells display superior ADCC than autologous. Effector cells for ADCC were (i) NK-92 cells not expressing FcR, (ii) NK-92 cells transfected with a high-affinity Fc receptor, (iii) autologous NK cells from patients with CLL, (iv) allogeneic NK cells. Results suggest that ADCC contributes to killing of CLL cells by anti-CD20 antibodies (rituximab and veltuzumab), whereas mAbs against CD22 (epratuzumab) and CD23 (lumiliximab) showed minimal ADCC. The magnitude of anti-CD20 mediated ADCC did not correlate with antigen density of CD20. ADCC was not influenced by the FcR genotype expressed by autologous NK cells. Allogeneic NK cells were superior to autologous NK cells in killing primary CLL cells.

Iron-deficiency anemia: a medically treatable chronic anemia as a model for transfusion overuse

PURPOSE

Transfusion practice in patients with iron deficiency was reviewed.

PATIENTS AND METHODS

During the study period, records of 265 consecutive patients with an unsaturated iron-binding capacity of greater than 53.7 mumol/L were evaluated for possible iron-deficiency anemia.

RESULTS

Two hundred sixty-three patients met the study criteria for iron deficiency. Of these patients, 50 received 1 or more units of red blood cells (RBCs). The transfusion therapy of 12 patients could not be justified; physicians used laboratory results rather than the clinical status of the patients to initiate transfusion therapy. As a result, units of RBCs were transfused to raise the hematocrit to an arbitrarily chosen level. Furthermore, iron therapy was not prescribed for 97 of the 263 iron-deficient patients, including 11 of the patients for whom transfusion was justifiable and 2 patients for whom transfusion could not be justified. Based on records reviewed, no work-up was initiated to identify the cause of iron deficiency in 13 patients, including 4 patients who received transfusions.

CONCLUSION

These findings suggest that the evaluation and treatment of iron deficiency, including transfusion therapy for that condition, may be problematic. In view of the risks of blood transfusion therapy, improvement in transfusion practices for iron deficiency should be emphasized.

Metabolic evidence of cobalamin deficiency in bone marrow cells harvested for transplantation from donors given nitrous oxide

Nitrous oxide inactivates cobalamin, but clinically apparent sequelae ensue in nondeficient individuals only when exposure is prolonged. The gas is widely used in anesthesia, therefore, and is commonly given to donors during harvesting of their bone marrow cells for transplantation. The present study shows that nitrous oxide administered for only 75-120 minutes induced mild but unequivocal DNA synthetic abnormalities attributable to cobalamin deficiency in the harvested marrow cells of 4 out of 5 donors; the deoxyuridine suppression test in these 4 patients showed abnormal results more than 4 standard deviations above the reference mean. Metabolic evidence of cobalamin deficiency in cryopreserved cells diminished only slightly when they were thawed and retested 1 day later, but was no longer detectable in cells thawed and tested on the 3rd day. In contrast, cells harvested under nitrous oxide-free anesthesia in 4 subjects showed no evidence of cobalamin deficiency in the deoxyuridine suppression test. These results demonstrate that even relatively brief exposure to nitrous oxide induces cobalamin deficiency in harvested bone marrow cells, and that the cells remain metabolically impaired for more than 24 hours. Although clinical sequelae are not apparent at this time, the several potential implications of our findings indicate that the use of nitrous oxide in bone marrow transplantation needs to be evaluated further.

Autoimmune cytopenias in pernicious anemia: a report of four cases and review of the literature

Pernicious anemia appears to be autoimmune in origin and is associated with immune disorders of several organ systems. We report 4 patients with pernicious anemia and immune cytopenias, an association that may sometimes pose diagnostic problems unless specifically considered. Pernicious anemia coexisted with or was closely followed by idiopathic thrombocytopenic purpura in 3 patients and by autoimmune hemolytic anemia in a 4th patient. In addition to cobalamin therapy, all patients required corticosteroids (2 also received danazol), while 1 also required splenectomy. All 4 patients were women. The 3 patients with idiopathic thrombocytopenic purpura were also blood group O and were iron-deficient. Autoimmune cytopenias may occur in patients with treated or untreated pernicious anemia and require specific therapy.

Hostility measurement and its relationship to fantasy capacity

Two-hundred and three male high school freshmen and sophomore students were administered a daydreaming questionnaire, Buss-Durkee Hostility Inventory, and Rotter ISB. The latter was scored for hostility by the Renner, Maher, and Campbell method. The Subjects also rated one another on a sociometric scale measuring behavioral hostility. Subjects were divided into high and low fantasy groups. Analyses of variance were computed on the hostility measure data for 108 Subjects. The independent variables were obtained for the fantasy capacity measure and not for the peer rating measure. There was no positive correlation between the sociometric ratings and the hostility measures. In view of the results, the hostility measurement instruments are interpreted as measures of an individual's capacity to regard himself as hostile, rather than as measures of the actual hostility of his behavoir.

Severe neutropenia in CHOP occurs most frequently in cycle 1: a predictive model

Chemotherapy used to treat lymphoma can cause severe neutropenia. Risk models have identified factors that predict neutropenia across all chemotherapy cycles. We used clinical information obtained during pretreatment evaluation to develop a predictive model for severe neutropenia in the first cycle of cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) chemotherapy. This case series study included lymphoma patients receiving CHOP chemotherapy with or without rituximab who did not receive pre-emptive hematopoietic growth factor. Risk factors for neutropenia were identified from previously published models and included age >or=65 years, hypoalbuminemia, renal/cardiovascular disease, anemia, abnormal bone marrow and increased lactate dehydrogenase (LDH). A composite score equal to the number of pretreatment risk factors was used to predict severe neutropenia in cycle 1. Fifty-three percent of patients (47 of 89) had severe neutropenia, with 70% of first episodes occurring during cycle 1. Eighty-two percent of first-cycle, severe neutropenia events occurred in patients >or=65-years-old. In univariate analysis, age >or=65 years and increased baseline LDH were significantly associated with increased risk for severe neutropenia in cycle 1. In logistic regression modeling, the probability of severe neutropenia in cycle 1 increased as the number of pretreatment risk factors increased, with a one-unit increase in risk score resulting in a 2.3-fold increase in severe neutropenia. The study results suggest that data obtained before initiating CHOP-based chemotherapy can be used to identify those patients who are at risk for severe neutropenia in cycle 1. If validated, our model could be used to identify patients who would benefit from early use of growth factors.

Racial differences in blood pressure among urban adolescents

The purpose of this study was to determine if there are racial differences in the blood pressure patterns among urban adolescents. Blood pressure (BP) was measured according to Task Force guidelines in health-screening and education sessions conducted in urban public and parochial high schools. The prevalence of BP > or = 95th% (HBP) on initial screening was determined in a population of 3,349 students. Differences in prevalence of HBP among race, sex, and age groups were tested for significance by chi 2 analysis. The overall prevalence of HBP in this urban adolescent population was 8.1%. Significant race differences were present in females (blacks = 6.6% versus non-Hispanics = 2.9%, p < 0.01). Within the black females, HBP occurred more frequently among the girls attending predominantly black public schools (7.7%) compared to an interracial parochial school (2.0%) p < 0.001. This difference could not be explained by weight, height, or the occurrence of obesity. The observed BP differences within black females, by school, may reflect a family-environment effect on cardiovascular risk.

Stenting for treatment of coronary vasospasm

Following an acute anterior myocardial infarction, a 56-yr-old female underwent two balloon angioplasty procedures for a recurrent proximal left anterior descending artery stenosis. She had recurrent angina pectoris. Angiography showed a noncritical restenosis with marked provocable superimposed vasospasm. Despite repeat balloon dilatation and stenting of the lesion, she developed recurrent symptoms. One month later, angiography showed progressive fixed disease and reversible spasm proximal and distal to, but not involving, the stented arterial segment. She underwent single-vessel coronary artery bypass grafting, and is asymptomatic at 6-mo follow-up.

Cerebrospinal fluid beta-endorphin and cortisol study in Rett syndrome

An evaluation of cerebrospinal fluid and plasma beta-endorphin and cortisol levels was performed in 15 girls affected with classic Rett syndrome. There were no differences between the patient group and the control group in plasma cortisol and beta-endorphin levels. But in Rett syndrome, a significant increase in beta-endorphin was noted in the cerebrospinal fluid, with an elevation of the cerebrospinal fluid/plasma beta-endorphin ratio and a decrease in cerebrospinal fluid cortisol. A substantial overlap between patients and control group diminishes the diagnostic value of cerebrospinal fluid beta-endorphin assay in girls suspected of having Rett syndrome.

Locus of control and effects of failure on perfomance and perceived competence

Reactions to related performance feedback of 117 internal and external eighth-grade children were investigated under conditions which made denial of personal responsibility for outcomes difficult. Both internals and externals were equally pleased by success feedback and displeased by failure and their competence judgement was influenced by the feedback received. However, internals exhibited more effective coping with failure than did externals. They improved their performance following failure feedback relatively more than after success and no external feedback conditions, and their percieved competance did not decrease in comparison with externals.

Early and late assessment of the Micro Stent PL coronary stent for restenosis and suboptimal balloon angioplasty

This prospective study represents the initial assessment of the Micro Stent PL (Arterial Vascular Engineering, Inc.) coronary stent. From one to three radiopaque stainless steel stents, each measuring 4 mm long, were premounted onto specially designed balloon catheters. A total of 123 stents were implanted in 41 patients without procedural failure or complications. Stent dislodgment proved a concern, with 7 of 123 stents (5.7%) moving > 3 mm from the site of placement and late downstream migration occurring in an additional patient. Subacute stent thrombosis occurred in two patients (5%). Six-month angiographic follow-up was available in 37 of 41 patients (90%). Minimal lumen diameter at baseline was 0.93 +/- 0.51 mm, increasing to 2.74 +/- 0.49 mm after stenting, and falling to 1.66 +/- 0.89 mm at 6 months; this represents a late loss of 60% of the initial gain. Restenosis, based on a binary definition of > 50% diameter stenosis, was documented in 18 patients (49%). Advantages of the Micro Stent PL include its radiopacity and marked ease of distal delivery. The potential for stent dislodgment has implications for future stent designs. The role of the Micro Stent PL in managing restenosis is unclear, but it appears useful in the management of dissection and threatened closure after balloon angioplasty.

Paracentric inversion of chromosome 3 (q21q26) in a patient with chronic myelomonocytic leukemia and a normal platelet count

Clonal chromosomal abnormalities occur in about one-third of patients with chronic myelomonocytic leukemia (CMMoL) and are usually those found in other myelodysplastic syndromes. Abnormalities of chromosome 3, which have been associated with abnormal thrombopoiesis, are relatively uncommon. A patient with CMMoL with inv(3)(q21q26) and normal thrombopoiesis is presented, and the cytogenetics of CMMoL are reviewed. The possible significance of chromosome 3 in thrombopoiesis is discussed.

Parental influence on adolescents' imagination

It was hypothesized that a permissive democratic parental attitude towards childrearing and favorable accepting attitude towards children's imagination are conducive to the development of their adolescent children's imaginative ability. It was also hypothesized that the mothers' role is more crucial than that of the fathers. The subjects were 104 adolescent Israeli boys and girls and their parents. The subjects were administered four scales of the Imaginal Processes Inventory and the Children's Report of Parental Behavior Inventory. The parents filled out a questionnaire devised to study their attitude to children's imagination. The first two hypotheses were not confirmed. The data point in the opposite direction as regards the first hypothesis. There was partial conformation for the third hypothesis. The data were also discussed in relation to healthy and neurotic daydreaming.

Pullback atherectomy with the Arrow-Fischell atherectomy device

The Arrow-Fischell pullback atherectomy catheter is designed to circumferentially debulk and retrieve coronary atheroma. We performed pullback atherectomy before balloon angioplasty or stenting in 41 patients. The device crossed the target lesion in 38 (93%) and obtained tissue in 36 (88%). All procedures were completed successfully and without myocardial infarction, emergency cardiac surgery, or death. Complications included major spasm in 8 patients, postprocedural abrupt closure in 1, and otherwise uncomplicated arterial perforation in 2. Pullback atherectomy can be performed relatively safely, but is more difficult than balloon angioplasty, obtains less tissue than directional atherectomy, and is associated with significant limitations.

Hypotension during surgery for femoral neck fracture in elderly patients: effect of anaesthetic techniques. A retrospective study

BACKGROUND

The aim of this retrospective study was to compare the incidence of hypotension between different anaesthetic techniques, including general anaesthesia (GA), spinal anaesthesia single injection (SA), continuous spinal anaesthesia with 2.5 mg bolus injections as needed (CSA 2.5) or 5 mg bolus injections as needed (CSA 5) in elderly patients (>75 yrs old) undergoing surgery for femoral neck fractures.

METHODS

Demographic, surgical and hemodynamic data from 333 patients over a four year period within a single hospital were recorded and examined.

RESULTS

Forty-two patients underwent GA, 109 underwent SA, 61 underwent CSA 5, and 121 underwent CSA 2.5. Patients receiving GA, SA or CSA 5 had a higher incidence of hypotension (83%, 68%, and 34%, respectively) than patients who underwent CSA 2.5 (4%; P<0.05). The CSA 2.5 group required less colloid infusion (490+/-50 mL) than the GA and SA groups (810+/-330 and 645+/-230 mL, respectively). The CSA 2.5 group also required less crystalloid infusion volume (760+/-371 mL) than the GA group (1140+/-770 mL). Ephedrine infusion was higher in the GA and SA groups (30+/-10 and 26+/-9 mg, respectively) than the CSA 2.5 (15+/-8 mg; P<0.05).

CONCLUSION

This study demonstrated that CSA 2.5 causes fewer episodes of hypotension than other anaesthetic techniques for surgical repair of hip fracture in elderly patients.