Debilitating hip degeneration in trichothiodystrophy: Association with ERCC2/XPD mutations, osteosclerosis, osteopenia, coxa valga, contractures, and osteonecrosis

Trichothiodystrophy (TTD) is a rare, autosomal recessive, multisystem disorder of DNA repair and transcription with developmental delay and abnormalities in brain, eye, skin, nervous, and musculoskeletal systems. We followed a cohort of 37 patients with TTD at the National Institutes of Health (NIH) from 2001 to 2019 with a median age at last observation of 12 years (range 2-36). Some children with TTD developed rapidly debilitating hip degeneration (DHD): a distinctive pattern of hip pain, inability to walk, and avascular necrosis on imaging. Ten (27%) of the 37 patients had DHD at median age 8 years (range 5-12), followed by onset of imaging findings at median age 9 years (range 5-13). All 10 had mutations in the ERCC2/XPD gene. In 7 of the 10 affected patients, DHD rapidly became bilateral. DHD was associated with coxa valga, central osteosclerosis with peripheral osteopenia of the skeleton, and contractures/tightness of the lower limbs. Except for one patient, surgical interventions were generally not effective at preventing DHD. Four patients with DHD died at a median age of 11 years (range 9-15). TTD patients with ERCC2/XPD gene mutations have a high risk of musculoskeletal abnormalities and DHD leading to poor outcomes. Monitoring by history, physical examination, imaging, and by physical medicine and rehabilitation specialists may be warranted.

Value of treatment by comprehensive stroke services for the reduction of critical gaps in acute stroke care in Europe

Stroke is the second leading cause of death and dependency in Europe and costs the European Union more than €30bn, yet significant gaps in the patient pathway remain and the cost-effectiveness of comprehensive stroke care to meet these needs is unknown. The European Brain Council Value of Treatment Initiative combined patient representatives, stroke experts, neurological societies and literature review to identify unmet needs in the patient pathway according to Rotterdam methodology. The cost-effectiveness of comprehensive stroke services was determined by a Markov model, using UK cost data as an exemplar and efficacy data for prevention of death and dependency from published systematic reviews and trials, expressing effectiveness as quality-adjusted life-years (QALYs). Model outcomes included total costs, total QALYs, incremental costs, incremental QALYs and the incremental cost-effectiveness ratio (ICER). Key unmet needs in the stroke patient pathway included inadequate treatment of atrial fibrillation (AF), access to neurorehabilitation and implementation of comprehensive stroke services. In the Markov model, full implementation of comprehensive stroke services was associated with a 9.8% absolute reduction in risk of death of dependency, at an intervention cost of £9566 versus £6640 for standard care, and long-term care costs of £35 169 per 5.1251 QALYS vs. £32 347.40 per 4.5853 QALYs, resulting in an ICER of £5227.89. Results were robust in one-way and probabilistic sensitivity analyses. Implementation of comprehensive stroke services is a cost-effective approach to meet unmet needs in the stroke patient pathway, to improve acute stroke care and support better treatment of AF and access to neurorehabilitation.

The Nab experiment: A precision measurement of unpolarized neutron beta decay

Neutron beta decay is one of the most fundamental processes in nuclear physics and provides sensitive means to uncover the details of the weak interaction. Neutron beta decay can evaluate the ratio of axial-vector to vector coupling constants in the standard model, λ = gA/gV, through multiple decay correlations. The Nab experiment will carry out measurements of the electron-neutrino correlation parameter a with a precision of δa/a = 10−3 and the Fierz interference term b to δb = 3 × 10−3 in unpolarized free neutron beta decay. These results, along with a more precise measurement of the neutron lifetime, aim to deliver an independent determination of the ratio λ with a precision of δλ/λ = 0.03% that will allow an evaluation of Vud and sensitively test CKM unitarity, independent of nuclear models. Nab utilizes a novel, long asymmetric spectrometer that guides the decay electron and proton to two large area silicon detectors in order to precisely determine the electron energy and an estimation of the proton momentum from the proton time of flight. The Nab spectrometer is being commissioned at the Fundamental Neutron Physics Beamline at the Spallation Neutron Source at Oak Ridge National Lab. We present an overview of the Nab experiment and recent updates on the spectrometer, analysis, and systematic effects.

Availability of secondary prevention services after stroke in Europe: An ESO/SAFE survey of national scientific societies and stroke experts

Background

Recurrent stroke is associated with increased disability and cognitive impairment, but the availability of secondary prevention measures after transient ischaemic attack (TIA) or stroke in Europe is uncertain. This limits prioritisation of investment and development of national stroke strategies.

Methods

National stroke representatives throughout Europe were surveyed. Consensus panels reported national data if available, or else expert opinion, estimating the availability of each intervention by quintiles of patients, dichotomised for analysis at 60%. Countries were classified into tertiles of gross domestic product per capita.

Results

Of 50 countries, 46 responded; 14/45 (31%) had national stroke registries and 25/46 (54.3%) had national stroke strategies incorporating secondary prevention. Respondents reported that the majority of TIA patients were assessed by specialist services within 48 hours in 74.4% of countries, but in nine countries more than 20% of patients were seen after more than seven days and usually assessed by non-specialists (7/46 countries). Eighty percent of countries deferred blood pressure assessment to primary care, whilst lifestyle management programmes were commonly available in only 46% of countries. Although basic interventions were widely available, interventions frequently not available to more than 60% of patients included: ambulatory cardiac monitoring (40% countries); prescription (26%) and continuation (46%) of statins; blood pressure control at follow-up (44%); carotid endarterectomy within one month (15%); face-to-face follow-up in hospital (33%); direct oral anticoagulants (21%). Gross domestic product per capita and reimbursement of interventions were the commonest predictors of availability of interventions.

Conclusions

Provision of secondary prevention varied, with gaps in care prevalent throughout Europe, particularly in lower income countries.

Exploring mechanisms of IgE-mediated autoimmunity through the lens of bullous pemphigoid

Bullous pemphigoid (BP) is the most common autoimmune blistering disease characterized by pathogenic autoantibodies targeting collagen XVII (col XVII), a hemidesmosomal adhesion molecule. Early studies utilizing IgG were critical for establishing col XVII-specific antibodies as primary mediators of blister formation; however, these studies lacked key features of the disease, including urticarial erythema and eosinophilic infiltration, which are often associated with IgE. Although it was recognized that BP patients often had elevated circulating IgE, investigations into the pathogenicity of these antibodies was delayed until discovery of col XVII-specific IgE in BP sera. Since then, a variety of in-vivo and in-vitro studies have provided clear evidence that IgE autoantibodies are a key component of BP. Furthermore, studies utilizing IgE receptor blockade in BP patients were the first to confirm a pathogenic role of IgE autoantibodies in human autoimmunity. In this review we will utilize BP as a prototypical autoimmune disease to better understand how IgE autoantibodies participate in human autoimmunity.

Grain-size-independent plastic flow at ultrahigh pressures and strain rates

A basic tenet of material science is that the flow stress of a metal increases as its grain size decreases, an effect described by the Hall-Petch relation. This relation is used extensively in material design to optimize the hardness, durability, survivability, and ductility of structural metals. This Letter reports experimental results in a new regime of high pressures and strain rates that challenge this basic tenet of mechanical metallurgy. We report measurements of the plastic flow of the model body-centered-cubic metal tantalum made under conditions of high pressure (>100  GPa) and strain rate (∼10(7)  s(-1)) achieved by using the Omega laser. Under these unique plastic deformation ("flow") conditions, the effect of grain size is found to be negligible for grain sizes >0.25  μm sizes. A multiscale model of the plastic flow suggests that pressure and strain rate hardening dominate over the grain-size effects. Theoretical estimates, based on grain compatibility and geometrically necessary dislocations, corroborate this conclusion.

Cortisol levels and history of depression in acute coronary syndrome patients

BACKGROUND

Depressed mood following an acute coronary syndrome (ACS) is a risk factor for future cardiac morbidity. Hypothalamic-pituitary-adrenal (HPA) axis dysregulation is associated with depression, and may be a process through which depressive symptoms influence later cardiac health. Additionally, a history of depression predicts depressive symptoms in the weeks following ACS. The purpose of this study was to determine whether a history of depression and/or current depression are associated with the HPA axis dysregulation following ACS.

METHOD

A total of 152 cardiac patients completed a structured diagnostic interview, a standardized depression questionnaire and a cortisol profile over the day, 3 weeks after an ACS. Cortisol was analysed using: the cortisol awakening response (CAR), total cortisol output estimated using the area under the curve method, and the slope of cortisol decline over the day.

RESULTS

Total cortisol output was positively associated with history of depression, after adjustment for age, gender, marital status, ethnicity, smoking status, body mass index (BMI), Global Registry of Acute Cardiac Events (GRACE) risk score, days in hospital, medication with statins and antiplatelet compounds, and current depression score. Men with clinically diagnosed depression after ACS showed a blunted CAR, but the CAR was not related to a history of depression.

CONCLUSIONS

Patients with a history of depression showed increased total cortisol output, but this is unlikely to be responsible for associations between depression after ACS and later cardiac morbidity. However, the blunted CAR in patients with severe depression following ACS indicates that HPA dysregulation is present.

Emotional triggering and low socio-economic status as determinants of depression following acute coronary syndrome

BACKGROUND

The determinants of depression following acute coronary syndrome (ACS) are poorly understood. Triggering of ACS by emotional stress and low socio-economic status (SES) are predictors of adverse outcomes. We therefore investigated whether emotional triggering and low SES predict depression and anxiety following ACS.

METHOD

This prospective observational clinical cohort study involved 298 patients with clinically verified ACS. Emotional stress was assessed for the 2 h before symptom onset and compared with the equivalent period 24 h earlier using case-crossover methods. SES was defined by household income and education. Depression was measured with the Beck Depression Inventory and the Hamilton Rating Scale for Depression and anxiety with the Hospital Anxiety and Depression Scale 3 weeks after ACS and again at 6 and 12 months. Age, gender, ethnicity, marital status, the Global Registry of Acute Coronary Events risk score, duration of hospital stay and history of depression were included as covariates.

RESULTS

Emotional stress during the 2-h hazard period was associated with increased risk of ACS (odds ratio 1.88, 95% confidence interval 1.01-3.61). Both low income and emotional triggering predicted depression and anxiety at 3 weeks and 6/12 months independently of covariates. The two factors interacted, with the greatest depression and anxiety in lower income patients who experienced acute emotional stress. Education was not related to depression.

CONCLUSIONS

Patients who experience acute emotional stress during their ACS and are lower SES as defined by current affluence and access to resources are particularly vulnerable to subsequent depression and anxiety.

Classification and 3D averaging with missing wedge correction in biological electron tomography

Strategies for the determination of 3D structures of biological macromolecules using electron crystallography and single-particle electron microscopy utilize powerful tools for the averaging of information obtained from 2D projection images of structurally homogeneous specimens. In contrast, electron tomographic approaches have often been used to study the 3D structures of heterogeneous, one-of-a-kind objects such as whole cells where image-averaging strategies are not applicable. Complex entities such as cells and viruses, nevertheless, contain multiple copies of numerous macromolecules that can individually be subjected to 3D averaging. Here we present a complete framework for alignment, classification, and averaging of volumes derived by electron tomography that is computationally efficient and effectively accounts for the missing wedge that is inherent to limited-angle electron tomography. Modeling the missing data as a multiplying mask in reciprocal space we show that the effect of the missing wedge can be accounted for seamlessly in all alignment and classification operations. We solve the alignment problem using the convolution theorem in harmonic analysis, thus eliminating the need for approaches that require exhaustive angular search, and adopt an iterative approach to alignment and classification that does not require the use of external references. We demonstrate that our method can be successfully applied for 3D classification and averaging of phantom volumes as well as experimentally obtained tomograms of GroEL where the outcomes of the analysis can be quantitatively compared against the expected results.

Initiatives to improve minority participation in cancer clinical trials

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Background: Barriers to minority research participation fall into two categories with respect to research institutions: 1) Community-based factors: historical events, attitudes towards the medical system, trust in research, and referral patterns and geographic distribution of providers serving minority patients. 2) Institutional factors: system and policy issues that define where patients receive care, researcher and staff attitudes and practices, and infrastructure availability to support minority accrual. Much attention has focused on community factors but with little evidence to support specific interventions. Recent studies suggest that internal barriers may play an even more significant role. The Siteman Cancer Center’s Program for the Elimination of Cancer Disparities (PECaD) uses several internal strategies as part of its comprehensive program. Methods: First, the Siteman Cancer has raised substantial funds and changed institutional policies to improve access to cancer services for minority populations, particularly from the African-American community. Second, PECaD implemented a trial monitoring program requiring cancer investigators to set and achieve appropriate accrual based on the patient population treated in each disease area. Third, through trial monitoring and consultation with investigators, PECaD is developing core resources to help recruit and retain minority participants. Results: This approach has led to marked improvement in representative participation in cancer research. In all categories of breast research, African-American participation has climbed from 9% to 28% over five years. In nearly all disease areas, African American participation in therapeutic trials has increased steadily and in some cases exceeds the proportion of African-American patients treated in that disease area. Conclusions: Eliminating cancer disparities requires representative research participation. To achieve this goal, research institutions need to critically examine and implement changes in systems, practices and culture. Leadership, institutional commitment, and operational restructuring can result in significant change even with relatively modest financial investment.

No significant financial relationships to disclose.

209 RISKS OF TRANSMITTING MYCOBACTERIUM AVIUM SSP. PARATUBERCULOSIS BY TRANSFER OF IN VIVO-DERIVED AND IN VITRO-FERTILIZED BOVINE EMBRYOS

Paratuberculosis (Johne's disease) is a chronic infectious disease of cattle and other domestic and wild ruminants caused by Mycobacterium avium ssp. paratuberculosis (Map) which is widespread throughout the world. The disease is characterized by persistent diarrhea, weight loss, and eventually death. In addition to interest in the economic losses, there has been an increasing interest in eradicating the disease due to the potential involvement of the causative microorganism in Crohn's disease, a debilitating chronic enteritis in man. Experiments were conducted to determine the possibility of transmission of Map by embryo transfer (ET) and the association of Map with in vivo-derived and in vitro-fertilized (IVF) embryos. These experiments involved (1) collection of embryos from naturally infected donors (n = 5) and transfer of those embryos to uninfected recipients (n = 12) and testing of others for Map by culture on Herrold's medium with mycobactin or by PCR; and (2) in vitro exposure of in vivo-derived and IVF embryos to Map and their subsequent transfer to uninfected recipients. Experiment 1 revealed the presence of Map in the uterine horns of all five subclinically infected donors, but it was not detected in association with sequentially washed in vivo-derived embryos by culture or by PCR. In Experiment 2, a high proportion of both in vivo-derived and IVF embryos exposed to Map in vitro tested positive for Map even after sequential washings as recommended by IETS. Transfer of in vivo-derived and IVF embryos that had been exposed to Map, and then washed, into 18 recipients resulted in 13 pregnancies and 8 calves born without evidence of disease transmission to either the recipients or the offspring over the following 5 year period. In conclusion, it is unlikely that Map will be transmitted by ET when the embryos have been processed according to the washing protocols recommended by the IETS.

Transcription factor binding and induced transcription alter chromosomal c-myc replicator activity

The observation that transcriptionally active genes generally replicate early in S phase and observations of the interaction between transcription factors and replication proteins support the thesis that promoter elements may have a role in DNA replication. To test the relationship between transcription and replication we constructed HeLa cell lines in which inducible green fluorescent protein (GFP)-encoding genes replaced the proximal approximately 820-bp promoter region of the c-myc gene. Without the presence of an inducer, basal expression occurred from the GFP gene in either orientation and origin activity was restored to the mutant c-myc replicator. In contrast, replication initiation was repressed upon induction of transcription. When basal or induced transcription complexes were slowed by the presence of alpha-amanitin, origin activity depended on the orientation of the transcription unit. To test mechanistically whether basal transcription or transcription factor binding was sufficient for replication rescue by the uninduced GFP genes, a GAL4p binding cassette was used to replace all regulatory sequences within approximately 1,400 bp 5' to the c-myc gene. In these cells, expression of a CREB-GAL4 fusion protein restored replication origin activity. These results suggest that transcription factor binding can enhance replication origin activity and that high levels of expression or the persistence of transcription complexes can repress it.

Hepatitis C virus cell culture replication systems: their potential use for the development of antiviral therapies

Hepatitis C virus is a significant public health problem. Current drug regimens have low efficacy against some hepatitis C virus genotypes, while no vaccine is available. The absence of an efficient cell culture system and an accessible small animal model to study hepatitis C virus replication and pathogenesis are major obstacles to the development of effective antiviral therapies. Studies of surrogate model systems, either related viruses or chimeric viruses containing part of the hepatitis C virus genome, have given insight into hepatitis C virus replication, in addition to being a powerful tool for drug discovery. The recent development of an efficient system for the initiation of replication in cell culture provides a viable screen for inhibitors of hepatitis C virus replication. It also brings us much closer to the ultimate goal of an infectious cell culture system for hepatitis C virus.

A unique murine monoclonal antibody recognizing HLA-B53, B37, B51, B52, +/-B44

Monoclonal antibodies have played an important role in studying the biochemistry of the HLA-Class I molecules. Some murine anti-HLA mAbs can identify configurations of HLA epitopes that have never been reported in human allosera. One of these configurations is identified by an IgM mAb designated as: BHA-1441. This antibody was produced using a lymphoblastoid cell line typed as: A*02, A*25; B*38, B*4402/4405; C*0501, C*07, BW4, as the immunogen. A lymphocytotoxicity test of this mAb over a panel of 109 frozen, 452 fresh and, later, 44 DNA typed T cells revealed its specificity as B53, 37, 51, 52, +/- 44. All of the antigens recognized by this mAb share the Bw4 motif at positions 81-83, except for the HLA-B37, which shares only 82L and 83R. Furthermore, while B37 and B44 cross-react due to the aspartic acid (D) substitution at position 156, the reactivity with B53, B5 (51,52), B37 and 60% of B44 cells, makes it unlikely that the target epitope could be due only to the primary amino-acid sequence. The antibody-binding site might involve changes in tertiary structure and peptides bound by the MHC. BHA-1441 is an interesting tool to study and type the HLA-B53 antigen and its cross-reactive epitopes.

Herpes simplex virus 1 open reading frames O and P are not necessary for establishment of latent infection in mice

Open reading frame (ORF) O and ORF P partially overlap and are located antisense to the gamma(1)34.5 gene within the domain transcribed during latency. In wild-type virus-infected cells, ORF O and ORF P are completely repressed during productive infection by ICP4, the major viral transcriptional activator/repressor. In cells infected with a mutant in which ORF P was derepressed there was a significant delay in the appearance of the viral alpha-regulatory proteins ICP0 and ICP22. The ORF O protein binds to and inhibits ICP4 binding to its cognate DNA site in vitro. These characteristics suggested a role for ORF O and ORF P in the establishment of latency. To test this hypothesis, two recombinant viruses were constructed. In the first, R7538(P-/O-), the ORF P initiator methionine codon, which also serves as the initiator methionine codon for ORF O, was replaced and a diagnostic restriction endonuclease was introduced upstream. In the second, R7543(P-/O-)R, the mutations were repaired to restore the wild-type virus sequences. We report the following. (i) The R7538(P-/O-) mutant failed to express ORF O and ORF P proteins but expressed a wild-type gamma(1)34.5 protein. (ii) R7538(P-/O-) yields were similar to that of the wild type following infection of cell culture or following infection of mice by intracerebral or ocular routes. (iii) R7538(P-/O-) virus reactivated from latency following explanation and cocultivation of murine trigeminal ganglia with Vero cells at a frequency similar to that of the wild type, herpes simplex virus 1(F). (iv) The amount of latent R7538(P-/O-) virus as assayed by quantitative PCR is eightfold less than that of the repair virus. The repaired virus could not be differentiated from the wild-type parent in any of the assays done in this study. We conclude that ORF O and ORF P are not essential for the establishment of latency in mice but may play a role in determining the quantity of latent virus maintained in sensory neurons.

Clinical practice guidelines: the need for improved implementation strategies

Although substantial resources have been spent developing clinical practice guidelines, little effort has been made to evaluate the effectiveness of their implementation. In the absence of effective implementation, CPGs will have minimal impact on changing behaviours. This article critically reviews the literature and identifies a number of reasons why these guidelines have not been implemented successfully. If CPGs are to have a positive impact upon clinical behaviour and practice, then more aggressive and positive implementation strategies are indicated. Five key ingredients for successful implementation of quality CPGs are identified and recommended.

Region tracking on level-sets methods

Since the work by Osher and Sethian on level-sets algorithms for numerical shape evolutions, this technique has been used for a large number of applications in numerous fields. In medical imaging, this numerical technique has been successfully used, for example, in segmentation and cortex unfolding algorithms. The migration from a Lagrangian implementation to a Eulerian one via implicit representations or level-sets brought some of the main advantages of the technique, i.e., topology independence and stability. This migration means also that the evolution is parametrization free. Therefore, we do not know exactly how each part of the shape is deforming and the point-wise correspondence is lost. In this note we present a technique to numerically track regions on surfaces that are being deformed using the level-sets method. The basic idea is to represent the region of interest as the intersection of two implicit surfaces and then track its deformation from the deformation of these surfaces. This technique then solves one of the main shortcomings of the very useful level-sets approach. Applications include lesion localization in medical images, region tracking in functional MRI (fMRI) visualization, and geometric surface mapping.

Prospective randomized comparative study of bipolar electrocoagulation versus heater probe for treatment of chronically bleeding internal hemorrhoids

BACKGROUND

Our purpose was to compare the efficacy, complications, failure rates, and crossovers of heater and bipolar probe treatments of chronically bleeding internal hemorrhoids.

METHODS

Eighty-one patients (31 female, 50 male) with mean age of 53 years had large (grade 2 to 3) internal hemorrhoids with bleeding for a mean of 12 years, had failed medical management, and were randomized in a prospective study of anoscopic treatments to heater versus bipolar probes. Failure was defined as a major complication or failure to reduce the size of all internal hemorrhoids with three or more treatments.

RESULTS

With similar background variables and no difference in treatment times, rectal bleeding and other symptoms were controlled in a shorter time with the heater probe than with the bipolar probe (77 versus 121 days). Five complications (fissures, bleeding, or rectal spasm) occurred with the bipolar probe, and two occurred with the heater probe. The heater probe caused more pain during treatments but had significantly fewer failures and crossovers.

CONCLUSIONS

For patients who had failed medical management of chronically bleeding internal hemorrhoids, the techniques and complications of heater and bipolar probes were similar, but pain was more common, failures and crossovers were less frequent, and the time to symptom relief was shorter with the heater probe than with the bipolar probe.

Identification of a 35-kilodalton serovar-cross-reactive flagellar protein, FlaB, from Leptospira interrogans by N-terminal sequencing, gene cloning, and sequence analysis

During the screening of antibodies to pathogenic leptospires, a murine monoclonal antibody (designated M138) was found to react with various serovars. An antigen of approximately 35 kDa from Leptospira interrogans serovar pomona, which reacted strongly with M138, was characterized by N-terminal amino acid sequencing and identified as a flagellin, a class B polypeptide subunit (FlaB) of the periplasmic flagella. The gene encoding the FlaB protein, flaB, was amplified from the genomic DNA of several pathogenic serovars by PCR with a single pair of oligonucleotide primers, suggesting that FlaB is highly conserved among these serovars. Cloning and sequence analysis of flaB from serovar pomona revealed that it contains an 849-bp open reading frame with a G + C content of 46.88% which encodes a 283-amino-acid protein with a calculated molecular mass of 31.297 kDa and a predicted pI of 9.065. A sequence comparison of flagellin proteins revealed that the amino acid sequence is most variable in the central portion of the serovar pomona FlaB, which is believed to contain specific sequence information and which may thus be useful in the design of DNA or synthetic peptide probes suitable for the detection of infection with pathogenic leptospires.

Transcription of the derepressed open reading frame P of herpes simplex virus 1 precludes the expression of the antisense gamma(1)34.5 gene and may account for the attenuation of the mutant virus

Open reading frame P (ORF P), located at the 3' terminus of the 8.5-kb DNA sequence transcribed during latency and almost completely antisense to the gamma(1)34.5 gene, is naturally repressed by infected cell protein 4 (ICP4), the major herpes simplex virus 1 regulatory protein. Earlier studies on cells infected with a mutant in which the expression of ORF P is derepressed have shown that (i) the accumulation of the alpha infected cell proteins 0 (ICP0) and 22 (ICP22), the products of spliced mRNAs, is reduced congruent with the binding of ORF P protein to p32, a component of the ASF/SF2 splicing factors, (ii) ORF P protein colocalizes with spliceosomes, (iii) both gamma(1)34.5 mRNA and protein are virtually undetectable, and (iv) the virus is attenuated on intracerebral inoculation in mice. We report the construction and characterization of two recombinant viruses: R7546, in which ORF P transcription was derepressed and the initiator methionine codon was replaced; and R7547, in which both mutations were repaired to the wild-type genotype. The mutations in R7546 do not alter the amino acid sequence of the gamma(1)34.5 gene. We report that (i) the reduction in the accumulation of gamma(1)34.5 mRNA and protein in cells infected with mutant viruses expressing derepressed ORF P genes reflects the effects of antisense transcription of ORF P rather than a function of ORF P protein, (ii) the attenuated phenotype of the viruses carrying derepressed ORF P genes is due largely to the absence of the gamma(1)34.5 protein, and (iii) the reduction in accumulation of ICP0 and ICP22 requires the expression of ORF P protein.

The product of ORF O located within the domain of herpes simplex virus 1 genome transcribed during latent infection binds to and inhibits in vitro binding of infected cell protein 4 to its cognate DNA site

The partially overlapping ORF P and ORF O are located within the domains of the herpes simplex virus 1 genome transcribed during latency. Earlier studies have shown that ORF P is repressed by infected cell protein 4 (ICP4), the major viral regulatory protein, binding to its cognate site at the transcription initiation site of ORF P. The ORF P protein binds to p32, a component of the ASF/SF2 alternate splicing factors; in cells infected with a recombinant virus in which ORF P was derepressed there was a significant decrease in the expression of products of key regulatory genes containing introns. We report that (i) the expression of ORF O is repressed during productive infection by the same mechanism as that determining the expression of ORF P; (ii) in cells infected at the nonpermissive temperature for ICP4, ORF O protein is made in significantly lower amounts than the ORF P protein; (iii) the results of insertion of a sequence encoding 20 amino acids between the putative initiator methionine codons of ORF O and ORF P suggest that ORF O initiates at the methionine codon of ORF P and that the synthesis of ORF O results from frameshift or editing of its RNA; and (iv) glutathione S-transferase-ORF O fusion protein bound specifically ICP4 and precluded its binding to its cognate site on DNA in vitro. These and earlier results indicate that ORF P and ORF O together have the capacity to reduce the synthesis or block the expression of regulatory proteins essential for viral replication in productive infection.

Phenotypic properties of herpes simplex virus 1 containing a derepressed open reading frame P gene

Open reading frame P (ORF P) maps in the viral DNA sequences transcribed during latency and is located antisense to the gamma 1 34.5 gene. Earlier studies have shown that the expression of ORF P is repressed by an infected cell protein no. 4 binding site straddling the transcription initiation site. We have made monospecific polyclonal antibodies to the protein and constructed a virus, designated ORF P++, in which the infected cell protein no. 4 binding site has been mutagenized, thereby allowing full expression of an unmodified ORF P gene from its natural promoter. We report the following findings. (i) The native protein forms multiple bands on denaturing polyacrylamide gels suggestive of extensive processing and aggregation of the protein; (ii) the protein accumulates in the nucleus in rod-shaped structures perpendicular to the axis of attachment of the infected cell to the solid matrix; (iii) the virus was highly attenuated on inoculation into mice by the intracerebral or ocular route, and virus was not recovered upon explantation of trigeminal ganglia; (iv) although protein synthesis was not prematurely shut off in the human neuroblastoma cell line SK-N-SH, gamma 1 34.5 protein was not detected in immunoblasts. Analyses of electrophoretically separated denatured RNAs indicated that in cells infected with the ORF P++ virus, there was a large increase in the amount of ORF P RNA and a corresponding decrease in the amount of gamma 1 34.5 RNA. We conclude that either the overproduction of ORF P protein blocks the expression of some herpes simplex virus 1 genes or derepression of the transcription of ORF P has a negative effect on the transcription of the antisense gamma 1 34.5 RNA.

A controlled study of ranitidine for the prevention of recurrent hemorrhage from duodenal ulcer

BACKGROUND

Hemorrhage is the most common complication of duodenal ulcer disease, but there is little information about the effectiveness and safety of long-term maintenance therapy with histamine H2-receptor blockers.

METHODS

We conducted a double-blind study in patients with endoscopically documented hemorrhage from duodenal ulcers. Patients were randomly assigned to maintenance therapy with ranitidine (150 mg at night) or placebo and were followed for up to three years. Endoscopy was performed at base line (to document that the ulcers had healed), at exit from the study, and when a patient had persistent ulcer symptoms unrelieved by antacids or had gastrointestinal bleeding. Symptomatic relapses without bleeding were treated with ranitidine; if the ulcer healed within eight weeks, the patient resumed taking the assigned study medication.

RESULTS

The two groups were similar at entry, which usually occurred about three months after the index hemorrhage. After a mean follow-up of 61 weeks, 3 of the 32 patients treated with ranitidine had recurrent hemorrhage, as compared with 12 of the 33 given placebo (P < 0.05). Half the episodes of recurrent bleeding were asymptomatic. One patient in the ranitidine group withdrew from the study because of asymptomatic thrombocytopenia during the first month.

CONCLUSIONS

For patients whose duodenal ulcers heal after severe hemorrhage, long-term maintenance therapy with ranitidine is safe and reduces the risk of recurrent bleeding.

Burst-promoting activity in the serum of patients with chronic renal failure undergoing long-term hemodialysis

Anemia in patients with chronic renal failure (CRF) is multifactorial, and while the majority will respond to the paternal administration of recombinant human erythropoietin (r-HuEPO), a role for coexistent plasma inhibitors and stimulators, such as burst-promoting activity (BPA), remains controversial. To evaluate the latter possibility, eight individuals with CRF on long-term hemodialysis, were studied before (mean hemoglobin 58.4 +/- 8.0 g/l and after 12 weeks of r-HuEPO therapy (mean hemoglobin 100.4 +/- 18.3 g/l). In vitro erythroid cultures using erythroid burst forming unit (BFU-E) and erythroid colony forming unit (CFU-E) assays were performed, plating 5 x 10(4) bone marrow mononuclear cells and comparing growth in heat-inactivated autologous serum with AB serum. Using Step III sheep erythropoietin (Connaught Laboratories, Willowdale, Ontario, Canada) (n = 4), mean BFU-E pre-therapy were 89.7 +/- 75.1, CFU-E were 418.5 +/- 150.6, whereas the corresponding figures in AB serum were 2.5 +/- 2.9 and 197 +/- 94.19, p = 0.1, p = 0.01, respectively. Similarly, with r-HuEPO (EPOCONN: Connaught Laboratories, Willowdale, Ontario, Canada) (n = 4), mean BFU-E were 145.25 +/- 103.3 in autologous serum and 31.0 +/- 56.75 in AB serum (p = 0.04). As controls, erythroid progenitors from two normal donors yielded 69 and 61 BFU-E colonies in autologous serum and 103 and 42 in AB serum; the corresponding CFU-E were 52 and 235 versus 136 and 137.(ABSTRACT TRUNCATED AT 250 WORDS)

Distribution of dysplasias and early invasive carcinoma in Barrett's esophagus

To assess the anatomic relationships between areas of dysplasia and "early" carcinoma, we evaluated histologically the entire mucosal surfaces of seven esophagectomy specimens resected for high-grade dysplasia or early invasive (intramucosal and submucosal) carcinoma. We developed surface area maps and assessed the various degrees of dysplasia or carcinoma at 10 equidistant points. Our analysis shows an equal likelihood of high-grade dysplasia and/or early invasive carcinoma occurring throughout the length of Barrett's epithelium. Foci of carcinoma appear within fields of Barrett's epithelium and adjacent to areas of dysplasia, supporting a dysplasia-carcinoma sequence. The amount of dysplastic epithelium appears related to the surface area of Barrett's epithelium present. However, we found no association between the extent of dysplasia and the likelihood of finding carcinoma. This study supports the current standard of practice for clinical surveillance of patients with Barrett's esophagus by uniformly distributed endoscopic biopsy of the complete length. In addition, the presence of any degree of dysplasia may be an indication for close clinical follow-up.

In vivo growth hormone (GH) response to human GH-releasing factor (GRF) or somatostatin (SRIF) in foetal pigs

The short-term effect of hypothalamic GRF and SRIF on the pituitary release of GH at different stages of gestation has been studied. In the present experiment eighteen gilts were used, six at each of 66, 88 and 110 days of gestation. Ventral laparotomy was performed under general anaesthesia and a section of uterus was exteriorized. Blood samples were obtained from the umbilical vein of three foetuses per gilt just prior to the injection of each foetus with either saline, 5 micrograms/kg of hGRF (1-44)NH2 or 50 micrograms/kg of SRIF into the umbilical vein. Additional blood samples were obtained 15, 30, 45 and 60 min post-injection. Serum samples were radioimmuno-assayed for GH (porcine). There was a treatment by gestational age interaction (P less than 0.01) on mean GH concentrations, area under the GH curve and GH peaks. While treatments had no effect (P greater than 0.1) on GH variables at 66 days of gestation, the area under the GH curve was slightly increased by GRF (P = 0.14) at day 88 and all GH variables were significantly increased (P less than 0.01)) by GRF at 110 days of gestation. There was a quadratic effect of time post-injection on GH concentrations at 88 (P less than 0.05) and 110 (P less than 0.001) days of gestation. There was no effect of SRIF injection (P greater than 0.1) on GH concentrations at any gestational age. In conclusion, the foetal pituitary responsiveness to GRF develops with foetal age and is maximal at the end of gestation, whereas there is no short-term response to a bolus of SRIF at any stage of gestation.

The effects of the anti-tumor agent mezerein on the cytotoxic capacity and oxidative metabolism of human blood cells

Mezerein, the most active antitumor compound isolated from the daphne species of plants, has a structural similarity to phorbol myristate acetate (PMA), the major active compound isolated from croton oil. PMA is known to have tumor promoting activity and is a potent inflammatory agent. Mezerein has similarly been reported to have potent inflammatory properties but appears to be a weaker tumor promoter than PMA. While the effect of PMA on the function and metabolism of human blood cells has been extensively studied, there is little similar information concerning mezerein. Therefore, in these studies, we have compared the capacities of mezerein and PMA to activate the cytotoxic capacity and oxidative metabolism of human granulocyte (PMNs), monocyte, lymphocyte, and mononuclear cell (lymphocytes and monocytes) cultures in vitro. Mezerein stimulated the oxidative metabolism of PMNs in an identical manner to PMA as indicated by a burst in the activity of the HMPS pathway, the production of H2O2, hydroxyl radical and stable oxidants. Mezerein also stimulated the release of thromboxane B2 from PMNs. Both compounds activated the oxidative metabolism of monocytes but not the oxidative metabolism of lymphocytes. The enhanced oxidative metabolism of the phagocytic cells was associated with an increased cytotoxicity against human red cells which are sensitive to oxidant damage but not against the NK resistant Raji lymphoblast cell line or the SW1116 colon tumor cell line. Of interest is that mezerein did not augment significantly the minimal cytotoxic capacity (NK activity) of mononuclear cells, monocytes or freshly isolated lymphocyte cultures against the tumor cell targets used in our experiments. However, lymphocyte cultures preincubated for 15 hours with mezerein had a marked enhancement of cytotoxicity against the tumor targets. This activation was not observed in similarly treated mononuclear cell cultures suggesting a suppressor activity of the monocytes. Our data suggest that the potent inflammatory activity of mezerein similar to PMA, may be related to its capacity to activate the oxidative and arachidonic metabolism of phagocytic cells. In addition, the capacity of mezerein to activate the cytotoxic capacity of lymphocytes may relate to its reported in vivo antitumor activity.

Comparison of low-power YAG laser and BICAP tumor probe for palliation of esophageal cancer strictures

The purposes of this study were (a) to determine the applicability of endoscopic palliation for patients with esophagogastric cancer strictures in a referral center, and (b) to compare the efficacy and safety of the BICAP tumor probe with the neodymiumyttrium-aluminum-garnet (YAG) laser for such palliation. Forty-two consecutive patients with weight loss and obstructive symptoms from an unresectable, malignant esophageal stricture were referred for endoscopic palliation. Fourteen patients did not meet the criteria for YAG laser or BICAP tumor probe treatment and other therapies were recommended. Twenty-eight patients were treated, the first 14 with low-power YAG laser and the last 14 with BICAP tumor probe. All patients had coagulation of malignant strictures in one session. Treated patients were similar in background variables and stricture lengths but twice as much thermal energy was needed for the YAG laser as the BICAP tumor probe treatment. Treatment results were not statistically different during the median follow-up and survival of 16 wk. As minor complications, either pain or edema requiring dilatation was more common in the YAG laser-treated group than the BICAP tumor probe group. Treatment-related esophageal strictures developed in 21% of patients treated with YAG laser. A fistula developed in 1 patient with noncircumferential cancer in the BICAP tumor probe group. Compared with only the intake of liquids before treatment, 86% of patients could eat a soft or solid diet after initial treatment with BICAP tumor probe or YAG laser. Our conclusions were that for BICAP tumor probe and YAG laser, endoscopic palliation efficacy and safety for circumferential esophageal cancer strictures were similar. The advantages of using the BICAP tumor probe were portability, lower equipment costs, and the ability to treat submucosal, long, or high esophageal cancer strictures in one session. Treatment with YAG laser was safer than BICAP tumor probe for exophytic, noncircumferential cancers because the laser could be directed endoscopically. Use of the BICAP tumor probe is not recommended for noncircumferential esophagogastric cancer strictures.

Cyclosporin-A radioimmunoassay: a modified method for whole blood determination

Cyclosporin-A levels were determined by radioimmunoassay in plasma or whole blood, using split samples collected from patients receiving this agent as the only form of immunosuppression following allogeneic bone marrow transplantation. In the plasma assay the temperature at which centrifugation took place was critical since the mean levels were approximately 30% higher with separation at 37 degrees C in comparison to 20 degrees C or lower. Furthermore, the level in whole blood samples was 2.4 times higher than that from the matching serum. In addition, anticoagulated blood that had been frozen and then thawed was technically more difficult to pipette and resulted in a recovery of only 83% of the cyclosporin when compared with assay using fresh blood. In contrast, consistent measurements were obtained either when whole blood was stored at 4 degrees C and then well mixed and diluted in buffer immediately prior to use or when such buffered samples were frozen and thawed immediately before analysis. The latter modifications render the whole blood assay a practical and reliable means for monitoring cyclosporin-A concentrations and may avoid excessive and the potentially nephrotoxic levels achieved when plasma levels are held in ranges previously considered therapeutic.

Malaria

Malaria continues to present staggering morbidity and mortality statistics. In this well-detailed article, the authors examine the increased incidence of malaria in many areas, describe the malarial parasites, discuss the clinical course, pathogenesis, diagnosis, and treatment, and address the issues of transfusion malaria, congenital malaria, immunity, chemoprophylaxis, and vaccine.

Alternaria osteomyelitis. Evidence of specific immunologic tolerance

A 31-year-old man had a maxillary sinus infection and osteomyelitis. In vitro lymphocyte transformation studies indicated that he had a specific immune tolerance to Alternaria organisms. The etiologic agent was recovered and was identified as Alternaria alternata.

Carpal tunnel syndrome caused by Mycobacterium fortuitum and Histoplasma capsulatum. Report of two cases

✓ Two unusual cases are presented in which carpal tunnel syndrome was found to be the presenting manifestation of Histoplasma capsulatum and atypical mycobacterial infection. General diagnostic and therapeutic points are reviewed.

Bone marrow culture in vitro. A technique for analysis and permanent recording of cellular composition

The in vitro cloning of haematopoietic progenitor cells derived from blood or bone marrow is now an established technique for the study of normal and abnormal blood formation. In semi-solid agar the results are conventionally recorded as the number of clusters or colonies that grow on the plate under controlled culture conditions. However, the demonstration of detailed morphology within these cellular aggregates remains unsatisfactory. Aspiration techniques are cumbersome and invariably disturb cellular relationships within the supporting matrix while supravital staining is limited by variable uptake of dye by the agar. We describe a method in which the entire cell-containing layer is removed from the Petri dish, fixed, and after mounting on a glass-slide, is air-dried. This preparation stains well with a wide variety of biological dyes, is minimally influenced by background colouration of the culture medium and excellent demonstration of morphologic detail is possible. A permanent record of the cellular composition of the culture is easily obtained by mounting the stained agar disc.

Acute leukaemia and allogeneic granulocyte support

Infusion of functional allogeneic granulocytes is rational therapy in pyrexial patients with severe neutropenia when combined with appropriate antibiotic administration. On the basis of our first year's experience we endorse this approach, but emphasise the need for further critical evaluation of these cells, and present an approach to placing this procedure on a more scientific basis.

Spindle cell carcinoma (pseudosarcoma) of the larynx

"Pseudosarcoma", initially considered a benign response of connective tissue to an adjacent squamous carcinoma, is now regarded as a spindle cell variant of epidermoid carcinoma. Nine cases of spindle cell carcinoma of the larynx are presented. Characteristically, the lesion appears as a large, gray, polypoid tumor. In contrast to other reports, a correlation between gross morphology and prognosis could not be made. The prognosis is more closely related to the size and location of the tumor. Biopsy specimens of the tumors in seven of the nine cases showed only the spindle cell pattern. This may be confused with granulation tissue. Spindle cell carcinoma was metastatic to the neck and lungs in three patients. Our average follow-up time was 3.8 years with two of the nine patients dying of recurrent disease. Most of our patients were successfully treated with conservation surgery.