First Measurement of Discrimination between Helium and Electron Recoils in Liquid Xenon for Low-Mass Dark Matter Searches

We report the first measurement of discrimination between low-energy helium recoils and electron recoils in liquid xenon. This result is relevant to proposed low-mass dark matter searches which seek to dissolve light target nuclei in the active volume of liquid-xenon time projection chambers. Low-energy helium recoils were produced by degrading α particles from ^{210}Po with a gold foil situated on the cathode of a liquid xenon time-projection chamber. The resulting population of helium recoil events is well separated from electron recoils and is also offset from the expected position of xenon nuclear recoil events.

First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment

The LUX-ZEPLIN experiment is a dark matter detector centered on a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA. This Letter reports results from LUX-ZEPLIN's first search for weakly interacting massive particles (WIMPs) with an exposure of 60 live days using a fiducial mass of 5.5 t. A profile-likelihood ratio analysis shows the data to be consistent with a background-only hypothesis, setting new limits on spin-independent WIMP-nucleon, spin-dependent WIMP-neutron, and spin-dependent WIMP-proton cross sections for WIMP masses above 9  GeV/c^{2}. The most stringent limit is set for spin-independent scattering at 36  GeV/c^{2}, rejecting cross sections above 9.2×10^{-48}  cm at the 90% confidence level.

Synergistic silencing of α-globin and induction of γ-globin by histone deacetylase inhibitor, vorinostat as a potential therapy for β-thalassaemia

β-Thalassaemia is one of the most common monogenic diseases with no effective cure in the majority of patients. Unbalanced production of α-globin in the presence of defective synthesis of β-globin is the primary mechanism for anaemia in β-thalassaemia. Clinical genetic data accumulated over three decades have clearly demonstrated that direct suppression of α-globin and induction of γ-globin are effective in reducing the globin chain imbalance in erythroid cells hence improving the clinical outcome of patients with β-thalassaemia. Here, we show that the histone deacetylase inhibitor drug, vorinostat, in addition to its beneficial effects for patients with β-thalassaemia through induction of γ-globin, has the potential to simultaneously suppress α-globin. We further show that vorinostat exhibits these synergistic beneficial effects in globin gene expression at nanomolar concentrations without perturbing erythroid expansion, viability, differentiation or the transcriptome. This new evidence will be helpful for the interpretation of existing clinical trials and future clinical studies that are directed towards finding a cure for β-thalassaemia using vorinostat.

Bi-allelic Loss-of-Function CACNA1B Mutations in Progressive Epilepsy-Dyskinesia

The occurrence of non-epileptic hyperkinetic movements in the context of developmental epileptic encephalopathies is an increasingly recognized phenomenon. Identification of causative mutations provides an important insight into common pathogenic mechanisms that cause both seizures and abnormal motor control. We report bi-allelic loss-of-function CACNA1B variants in six children from three unrelated families whose affected members present with a complex and progressive neurological syndrome. All affected individuals presented with epileptic encephalopathy, severe neurodevelopmental delay (often with regression), and a hyperkinetic movement disorder. Additional neurological features included postnatal microcephaly and hypotonia. Five children died in childhood or adolescence (mean age of death: 9 years), mainly as a result of secondary respiratory complications. CACNA1B encodes the pore-forming subunit of the pre-synaptic neuronal voltage-gated calcium channel Ca_v2.2/N-type, crucial for SNARE-mediated neurotransmission, particularly in the early postnatal period. Bi-allelic loss-of-function variants in CACNA1B are predicted to cause disruption of Ca²⁺ influx, leading to impaired synaptic neurotransmission. The resultant effect on neuronal function is likely to be important in the development of involuntary movements and epilepsy. Overall, our findings provide further evidence for the key role of Ca_v2.2 in normal human neurodevelopment.

Anaemia among females in child-bearing age: Relative contributions, effects and interactions of α- and β-thalassaemia

Introduction

Anaemia in women during pregnancy and child bearing age is one of the most common global health problems. Reasons are numerous, but in many cases only minimal attempts are made to elucidate the underlying causes. In this study we aim to identify aetiology of anaemia in women of child bearing age and to determine the relative contributions, effects and interactions of α- and β-thalassaemia in a region of the world where thalassaemia is endemic.

Methods

A cross sectional study was conducted at the Colombo North Teaching Hospital of Sri Lanka. The patient database of deliveries between January 2015 and September 2016 at University Obstetrics Unit was screened to identify women with anaemia during pregnancy and 253 anaemic females were randomly re-called for the study. Data were collected using an interviewer-administered questionnaire and haematological investigations were done to identify aetiologies.

Results

Out of the 253 females who were anaemic during pregnancy and were re-called, 8 were excluded due to being currently pregnant. Of the remaining 245 females, 117(47.8%) remained anaemic and another 22(9.0%) had non-anaemic microcytosis. Of anaemic females, 28(24.8%) were iron deficient, 40(35.4%) had low-normal serum ferritin without fulfilling the criteria for iron deficiency,18(15.3%) had β-haemoglobinopathy trait and 20(17.0%) had α-thalassaemia trait. Of females who had non-anaemic microcytosis, 14(66.0%) had α-thalassaemia trait. In 4 females, both α- and β-thalassaemia trait coexist. These females had higher levels of haemoglobin (p = 0.06), MCV (p<0.05) and MCH (p<0.01) compared to individuals with only β-thalassaemia trait. A significantly higher proportion of premature births (p<0.01) and lower mean birth weights (p<0.05) were observed in patients with α-thalassaemia trait.

Conclusions

Nearly one third of anaemic females in child bearing age had thalassaemia trait of which α-thalassemia contributes to a majority. Both α- and β-thalassaemia trait can co-exist and have ameliorating effects on red cell indices in heterozygous states. α-Thalassaemia trait was significantly associated with premature births and low birth weight. It is of paramount importance to investigate the causes of anaemia in women of child bearing age and during pregnancy in addition to providing universal iron supplementation.

The Loss of ATRX Increases Susceptibility to Pancreatic Injury and Oncogenic KRAS in Female But Not Male Mice

Background

Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer death in North America, accounting for >30,000 deaths annually. Although somatic activating mutations in KRAS appear in 97% of PDAC patients, additional factors are required to initiate PDAC. Because mutations in genes encoding chromatin remodelling proteins have been implicated in KRAS-mediated PDAC, we investigated whether loss of chromatin remodeler ɑ-thalassemia, mental-retardation, X-linked (ATRX) affects oncogenic KRAS's ability to promote PDAC. ATRX affects DNA replication, repair, and gene expression and is implicated in other cancers including glioblastomas and pancreatic neuroendocrine tumors. The hypothesis was that deletion of Atrx in pancreatic acinar cells will increase susceptibility to injury and oncogenic KRAS.

Methods

Mice allowing conditional loss of Atrx within pancreatic acinar cells were examined after induction of recurrent cerulein-induced pancreatitis or oncogenic KRAS (KRASG12D ). Histologic, biochemical, and molecular analysis examined pancreatic pathologies up to 2 months after induction of Atrx deletion.

Results

Mice lacking Atrx showed more progressive damage, inflammation, and acinar-to-duct cell metaplasia in response to injury relative to wild-type mice. In combination with KRASG12D, Atrx-deficient acinar cells showed increased fibrosis, inflammation, progression to acinar-to-duct cell metaplasia, and pre-cancerous lesions relative to mice expressing only KRASG12D. This sensitivity appears only in female mice, mimicking a significant prevalence of ATRX mutations in human female PDAC patients.

Conclusions

Our results indicate the absence of ATRX increases sensitivity to injury and oncogenic KRAS only in female mice. This is an instance of a sex-specific mutation that enhances oncogenic KRAS's ability to promote pancreatic intraepithelial lesion formation.

Large-scale discovery of novel genetic causes of developmental disorders

Despite three decades of successful, predominantly phenotype-driven discovery of the genetic causes of monogenic disorders, up to half of children with severe developmental disorders of probable genetic origin remain without a genetic diagnosis. Particularly challenging are those disorders rare enough to have eluded recognition as a discrete clinical entity, those with highly variable clinical manifestations, and those that are difficult to distinguish from other, very similar, disorders. Here we demonstrate the power of using an unbiased genotype-driven approach to identify subsets of patients with similar disorders. By studying 1,133 children with severe, undiagnosed developmental disorders, and their parents, using a combination of exome sequencing and array-based detection of chromosomal rearrangements, we discovered 12 novel genes associated with developmental disorders. These newly implicated genes increase by 10% (from 28% to 31%) the proportion of children that could be diagnosed. Clustering of missense mutations in six of these newly implicated genes suggests that normal development is being perturbed by an activating or dominant-negative mechanism. Our findings demonstrate the value of adopting a comprehensive strategy, both genome-wide and nationwide, to elucidate the underlying causes of rare genetic disorders.

Intra- and inter-rater reliability of jumping mechanography muscle function assessments

Muscle function can be assessed through jumping mechanography, where portable ground reaction force plates collect dynamic information as a subject jumps. The aim of this study was to assess both intra- and inter- rater reliability of jumping mechanography. Ten healthy adults underwent 3 sets of testing (collected by 3 different raters) at two separate sessions, one week apart. They performed a number of tests in each session: multiple one-legged hopping (M1LH; on right and left legs) and single two-legged jumps (S2LJ; with or without arm swing). The S2LJ assessed variables of power per body mass, jump height, velocity and efficiency; whereas, M1LH assessed maximum force per body mass and stiffness. Inter-rater coefficients of variation (CV) were less than 0.6% and 2.6% for the S2LJ and M1LH, respectively, for the primary outcome variables of power/body mass and force/body mass. Analyzing intra-rater results also produced CVs less than 5.3% for all variables. The present study reports that the Leonardo ground reaction force plate system yields reproducible results between sessions, without significant contribution of variability from the test operator. Jumping mechanography is an easy, safe and reliable method for the assessment of lower limb musculoskeletal function.

Standardization of the Maristán Scale of Informal Care in people with schizophrenia and other psychoses

OBJECTIVE

No instrument has been developed and validated across cultures to measure the degree of support provided by informal carers to people with schizophrenia. We aimed to develop such a measure.

METHOD

The Maristán Scale of Informal Care was developed directly from the views of patients with schizophrenia in six countries. Face-to-face interviews were carried out with participants and 103 were repeated after 30 days. Principal Axis Factoring followed by Promax rotation evaluated the structure of the scale. Horn's parallel combined with bootstrapping determined the number of factors. Cronbach's alpha estimated the scale's internal consistency and intra-class correlation its test-retest reliability.

RESULTS

A total of 164 interviews were undertaken, 103 with re-test. The Horn's Parallel Analysis and the analysis of the Promax rotation revealed one factor. Cronbach's alpha was 0.89. Intra-class correlation coefficient was 0.56 (95% CI 0.42-0.68) and this increased to 0.64 (95% CI 0.51-0.75) after removing two outlying values. Patients from Argentina recorded the lowest scores (poor informal support/care).

CONCLUSION

The Maristán Scale of Informal Care is a reliable instrument to assess the degree of support provided by informal carers to people with schizophrenia across cultures. A confirmatory factor analysis is needed to evaluate the stability of its factor structure.

A systematic genome-wide analysis of zebrafish protein-coding gene function

Since the publication of the human reference genome, the identities of specific genes associated with human diseases are being discovered at a rapid rate. A central problem is that the biological activity of these genes is often unclear. Detailed investigations in model vertebrate organisms, typically mice, have been essential for understanding the activities of many orthologues of these disease-associated genes. Although gene-targeting approaches and phenotype analysis have led to a detailed understanding of nearly 6,000 protein-coding genes, this number falls considerably short of the more than 22,000 mouse protein-coding genes. Similarly, in zebrafish genetics, one-by-one gene studies using positional cloning, insertional mutagenesis, antisense morpholino oligonucleotides, targeted re-sequencing, and zinc finger and TAL endonucleases have made substantial contributions to our understanding of the biological activity of vertebrate genes, but again the number of genes studied falls well short of the more than 26,000 zebrafish protein-coding genes. Importantly, for both mice and zebrafish, none of these strategies are particularly suited to the rapid generation of knockouts in thousands of genes and the assessment of their biological activity. Here we describe an active project that aims to identify and phenotype the disruptive mutations in every zebrafish protein-coding gene, using a well-annotated zebrafish reference genome sequence, high-throughput sequencing and efficient chemical mutagenesis. So far we have identified potentially disruptive mutations in more than 38% of all known zebrafish protein-coding genes. We have developed a multi-allelic phenotyping scheme to efficiently assess the effects of each allele during embryogenesis and have analysed the phenotypic consequences of over 1,000 alleles. All mutant alleles and data are available to the community and our phenotyping scheme is adaptable to phenotypic analysis beyond embryogenesis.

How genetically heterogeneous is Kabuki syndrome?: MLL2 testing in 116 patients, review and analyses of mutation and phenotypic spectrum

MLL2 mutations are detected in 55 to 80% of patients with Kabuki syndrome (KS). In 20 to 45% patients with KS, the genetic basis remains unknown, suggesting possible genetic heterogeneity. Here, we present the largest yet reported cohort of 116 patients with KS. We identified MLL2 variants in 74 patients, of which 47 are novel and a majority are truncating. We show that pathogenic missense mutations were commonly located in exon 48. We undertook a systematic facial KS morphology study of patients with KS at our regional dysmorphology meeting. Our data suggest that nearly all patients with typical KS facial features have pathogenic MLL2 mutations, although KS can be phenotypically variable. Furthermore, we show that MLL2 mutation-positive KS patients are more likely to have feeding problems, kidney anomalies, early breast bud development, joint dislocations and palatal malformations in comparison with MLL2 mutation-negative patients. Our work expands the mutation spectrum of MLL2 that may help in better understanding of this molecule, which is important in gene expression, epigenetic control of active chromatin states, embryonic development and cancer. Our analyses of the phenotype indicates that MLL2 mutation-positive and -negative patients differ systematically, and genetic heterogeneity of KS is not as extensive as previously suggested. Moreover, phenotypic variability of KS suggests that MLL2 testing should be considered even in atypical patients.

[Alpha-thalassemia/mental retardation syndrome (ATR-X) in two brothers - clinical characteristics, diagnostics and genetic counselling issues]

Alpha-thalassemia/mental retardation syndrome (ATR-X) is a neurodevelopmental disorder with characteristic clinical picture as well as presence of pathognomonic haemoglobin H inclusions (HbH) on peripheral blood examination. Typical features of this condition are: severe intellectual impairment, muscular hypotonia, delay of growth, genitourinary/skeletal abnormalities and characteristic facial dysmorphism. Molecular basis of the syndrome constitute mutations in ATR-X gene located on the long arm of X chromosome (Xq13). In this work, clinical characteristics of the molecularly confirmed case of ATR-X syndrome in two brothers are presented. The mother of both affected boys is an asymptomatic mutation carrier. In one of the brothers additional studies revealed the presence of de novo 1q21.1 microdeletion. ATR-X syndrome symptomatology, differential diagnostics issues as well as the aims of genetic counselling are described.

Design and characterization of thin multiple aperture infrared cameras

We describe a multiple-aperture long-wave infrared camera built on an uncooled microbolometer array with the objective of decreasing camera thickness. The 5 mm thick optical system is an f/1.2 design with a 6.15 mm effective focal length. An integrated image is formed from the subapertures using correlation-based registration and a least gradient reconstruction algorithm. We measure a 131 mK NETD. The system's spatial frequency is analyzed with 4 bar targets. With proper calibration, our multichannel interpolation results recover contrast for targets at frequencies beyond the aliasing limit of the individual subimages.

The structure of lifetime manic-hypomanic spectrum

BACKGROUND

The observation that bipolar disorders frequently go unrecognized has prompted the development of screening instruments designed to improve the identification of bipolarity in clinical and non-clinical samples. Starting from a lifetime approach, researchers of the Spectrum Project developed the Mood Spectrum Self-Report (MOODS-SR) that assesses threshold-level manifestations of unipolar and bipolar mood psychopathology, but also atypical symptoms, behavioral traits and temperamental features. The aim of the present study is to examine the structure of mania/hypomania using 68 items of the MOODS-SR that explore cognitive, mood and energy/activity features associated with mania/hypomania.

METHODS

A data pool of 617 patients with bipolar disorders, recruited at Pittsburgh and Pisa, Italy was used for this purpose. Classical exploratory factor analysis, based on a tetrachoric matrix, was carried out on the 68 items, followed by an Item Response Theory (IRT)-based factor analytic approach.

RESULTS

Nine factors were initially identified, that include Psychomotor Activation, Creativity, Mixed Instability, Sociability/Extraversion, Spirituality/Mysticism/Psychoticism, Mixed Irritability, Inflated Self-esteem, Euphoria, Wastefulness/Recklessness, and account overall for 56.4% of the variance of items. In a subsequent IRT-based bi-factor analysis, only five of them (Psychomotor Activation, Mixed Instability, Spirituality/Mysticism/Psychoticism, Mixed Irritability, Euphoria) were retained.

CONCLUSIONS

Our data confirm the central role of Psychomotor Activation in mania/hypomania and support the definitions of pure manic (Psychomotor Activation and Euphoria) and mixed manic (Mixed Instability and Mixed Irritability) components, bearing the opportunity to identify patients with specific profiles for a better clinical and neurobiological definition.

Using genomics to study how chromatin influences gene expression

A postgenome challenge is to understand how the code in DNA is converted into the biological processes underlying various cell fates. By establishing the appropriate technical tools, we are moving from an era in which such questions have been asked by studying individual genes to one in which large domains, whole chromosomes, and the entire human genome can be investigated. These developments will allow us to study in parallel the transcriptional program and components of the epigenetic program (nuclear position, timing of replication, chromatin structure and modification, DNA methylation) to determine the hierarchy and order of events required to switch genes on and off during differentiation and development.

Alpha thalassaemia-mental retardation, X linked

X-linked alpha thalassaemia mental retardation (ATR-X) syndrome in males is associated with profound developmental delay, facial dysmorphism, genital abnormalities and alpha thalassaemia. Female carriers are usually physically and intellectually normal. So far, 168 patients have been reported. Language is usually very limited. Seizures occur in about one third of the cases. While many patients are affectionate with their caregivers, some exhibit autistic-like behaviour. Patients present with facial hypotonia and a characteristic mouth. Genital abnormalities are observed in 80% of children and range from undescended testes to ambiguous genitalia. Alpha-thalassaemia is not always present. This syndrome is X-linked recessive and results from mutations in the ATRX gene. This gene encodes the widely expressed ATRX protein. ATRX mutations cause diverse changes in the pattern of DNA methylation at heterochromatic loci but it is not yet known whether this is responsible for the clinical phenotype. The diagnosis can be established by detection of alpha thalassaemia, identification of ATRX gene mutations, ATRX protein studies and X-inactivation studies. Genetic counselling can be offered to families. Management is multidisciplinary: young children must be carefully monitored for gastro-oesophageal reflux as it may cause death. A number of individuals with ATR-X are fit and well in their 30s and 40s.

Understanding α-Globin Gene Regulation: Aiming to Improve the Management of Thalassemia

Over the past 50 years, many advances in our understanding of the general principles controlling gene expression during hematopoiesis have come from studying the synthesis of hemoglobin. Discovering how the alpha- and beta-globin genes are normally regulated and documenting the effects of inherited mutations that cause thalassemia have played a major role in establishing our current understanding of how genes are switched on or off in hematopoietic cells. Previously, nearly all mutations causing thalassemia have been found in or around the globin loci, but rare inherited and acquired trans-acting mutations are being found more often. Such mutations have demonstrated new mechanisms underlying human genetic disease. Furthermore, they are revealing new pathways in the regulation of globin gene expression that, in turn, may open up new avenues for improving the management of patients with common types of thalassemia.

The ATRX syndrome protein forms a chromatin-remodeling complex with Daxx and localizes in promyelocytic leukemia nuclear bodies

ATRX syndrome is characterized by X-linked mental retardation associated with alpha-thalassemia. The gene mutated in this disease, ATRX, encodes a plant homeodomain-like finger and a SWI2/SNF2-like ATPase motif, both of which are often found in chromatin-remodeling enzymes, but ATRX has not been characterized biochemically. By immunoprecipitation from HeLa extract, we found that ATRX is in a complex with transcription cofactor Daxx. The following evidence supports that ATRX and Daxx are components of an ATP-dependent chromatin-remodeling complex: (i) Daxx and ATRX can be coimmunoisolated by antibodies specific for each protein; (ii) a proportion of Daxx cofractionates with ATRX as a complex of 1 MDa by gel-filtration analysis; (iii) in extract from cells of a patient with ATRX syndrome, the level of the Daxx-ATRX complex is correspondingly reduced; (iv) a proportion of ATRX and Daxx colocalize in promyelocytic leukemia nuclear bodies, with which Daxx had previously been located; and (v) the ATRX complex displays ATP-dependent activities that resemble those of other chromatin-remodeling complexes, including triple-helix DNA displacement and alteration of mononucleosome disruption patterns. But unlike the previously described SWI/SNF or NURD complexes, the ATRX complex does not randomize DNA phasing of the mononucleosomes, suggesting that it may remodel chromatin differently. Taken together, the results suggest that ATRX functions in conjunction with Daxx in a novel chromatin-remodeling complex. The defects in ATRX syndrome may result from inappropriate expression of genes controlled by this complex.

V beta 6+ T cells are obligatory for vaccine-induced immunity to Histoplasma capsulatum

We examined TCR usage to a protective fragment of heat shock protein 60 from the fungus, Histoplasma capsulatum. Nearly 90% of T cell clones from C57BL/6 mice vaccinated with this protein were Vbeta6+; the remainder were Vbeta14+. Amino acid motifs of the CDR3 region from Vbeta6+ cells were predominantly IxGGG, IGG, or SxxGG, whereas it was uniformly SFSGG for Vbeta14+ clones. Short term T cell lines from Vbeta6+-depleted mice failed to recognize Ag, and no T cell clones could be generated. To determine whether Vbeta6+ cells were functionally important, we eliminated them during vaccination. Depletion of Vbeta6+ cells abrogated protection in vivo and upon adoptive transfer of cells into TCR alphabeta(-/-) mice. Transfer of a Vbeta6+, but not a Vbeta14+, clone into TCR alphabeta(-/-) mice prolonged survival. Cytokine generation by Ag-stimulated splenocytes from immunized mice depleted of Vbeta6+ cells was similar to that of controls. The efficacy of the Vbeta6+ clone was associated with elevated production of IFN-gamma, TNF-alpha, and GM-CSF compared with that of the Vbeta14+ clone. More Vbeta6+ cells were present in lungs and spleens of TCR alphabeta(-/-) on day 3 postinfection compared with Vbeta14+ cells. Thus, a single Vbeta family was essential for vaccine-induced immunity. Moreover, the mechanism by which Vbeta6+ contributed to protective immunity differed between unfractionated splenocytes and T cell clones.

Penile cancer and human papilloma virus (HPV) in a human immunodeficiency virus (HIV)-infected patient

Only a handful of cases of penile carcinoma among human immunodeficiency virus (HIV)-infected males have been reported. This is surprising insofar as other anogenital malignancies associated with human papillomavirus (HPV) are over-represented in HIV-infected men and women. Herein we describe the case of an HIV seropositive 64-year-old Caucasian with a CD4+ T-lymphocyte count of 550 cells/mm3 and an invasive squamous cell cancer of the penis. He underwent radical penectomy to treat cancer initially confined to the penile shaft and glans penis, but ultimately succumbed to complications associated with metastatic disease. HPV type 18 was identified by in situ hybridization and polymerase chain reaction (PCR) studies in the primary tumor and in groin and lung metastasis. We also briefly review current thoughts regarding the epidemiology and pathogenesis of penile cancer, particularly in the setting of HPV and HIV co-infection.

Protective efficacy of H antigen from Histoplasma capsulatum in a murine model of pulmonary histoplasmosis

We previously reported that immunization with H antigen from Histoplasma capsulatum did not protect mice against an intravenous challenge with yeasts. Here, we investigated the utility of H antigen to protect mice in a model of pulmonary histoplasmosis. Mice immunized with H antigen and challenged intranasally 4 weeks postvaccination were protected against sublethal and lethal challenges with H. capsulatum yeasts. If the challenge was performed 3 months after vaccination, there was a reduction in fungal burden following sublethal challenge and a modest delay in mortality in mice given a lethal inoculum. Vaccination was associated with production of gamma interferon, granulocyte-macrophage colony-stimulating factor, interleukin-4, and interleukin-10 by splenocytes. Vaccination with H antigen was not accompanied by a major expansion of CD4(+) or CD8(+) cells in spleens of mice. These results demonstrate that H antigen may be useful as a protective immunogen against pulmonary exposure to H. capsulatum.

A longitudinal subspecialty experience for internal medicine residents

OBJECTIVE

Market and technology innovations have greatly changed the teaching and practice of medicine in the past 10 years. This report describes an innovation in the ambulatory education of internal medicine residents: a subspecialty continuity clinic.

METHODS

A subspecialty continuity clinic was developed to improve the training of internal medicine residents in caring for complex ambulatory patients. The clinic structure is discussed from the perspective of patients, residents, and subspecialists. Logistical challenges and solutions are described.

RESULTS

Two and one-half years into the program, feedback from residents and subspecialists has been positive. In-training examination scores are relatively higher in the involved specialties, and residents are managing illnesses they rarely saw in an outpatient setting before this program.

CONCLUSION

This experience suggests that a subspecialty continuity clinic is worthwhile and practical in educating primary care residents.

Recombinant murine granulocyte-macrophage colony-stimulating factor modulates the course of pulmonary histoplasmosis in immunocompetent and immunodeficient mice

Several endogenous cytokines, including granulocyte-macrophage colony-stimulating factor (GM-CSF), are necessary for eliminating Histoplasma capsulatum from tissues. In this study, we explored the efficacy of recombinant murine GM-CSF in the treatment of pulmonary histoplasmosis. This cytokine significantly reduced fungal burden in a dose-dependent manner. Pretreatment did not consistently produce a better result than treatment started after infection. The biological effectiveness of GM-CSF was not associated with modulation of lung cytokine production or alteration in lung inflammation, but it directly activated a nonadherent lung cell population to exert anti-Histoplasma activity. GM-CSF improved survival of T-cell-depleted mice exposed to H. capsulatum. When combined with a suboptimal amount of amphotericin B, GM-CSF enhanced survival of normal or T-cell-depleted mice given a lethal challenge. These results suggest that this cytokine may be useful as an adjunctive treatment for histoplasmosis.

Neutralization of endogenous granulocyte-macrophage colony-stimulating factor subverts the protective immune response to Histoplasma capsulatum

We examined the influence of endogenous GM-CSF on the course of primary and secondary pulmonary histoplasmosis. A high proportion (>/=75%) of C57BL/6 mice given mAb to GM-CSF did not survive primary infection, whereas 88-94% of infected controls survived. Analysis of leukocytes revealed significantly fewer CD4+ and CD8+ cells in lungs, but not airways, of anti-GM-CSF-treated mice as compared with infected controls. However, the histopathology was similar between the two groups. Lungs of mice given mAb to GM-CSF manifested depressed levels of TNF-alpha, IFN-gamma, and reactive nitrogen intermediates and elevated levels of IL-4 and IL-10. Administration of mAb to IL-4, to IL-10, or both restored protective immunity in GM-CSF-neutralized mice. In secondary infection, administration of mAb to GM-CSF exacerbated infection but did not alter survival over 30 days. The character of the inflammatory response was similar, and no differences were detected in Th1 or Th2 cytokine production between the two groups. Thus, endogenous GM-CSF is essential for survival in primary but not secondary infection, and blockade perturbs protective immunity. These findings reveal a new mechanism whereby GM-CSF contributes to host protection and demonstrate differences in control of primary and secondary histoplasmosis.

Treatment outcomes for female octogenarians with breast cancer

Scant information is available comparing the treatment outcomes of minor surgery (lumpectomy) versus extensive treatment (radical and simple mastectomy or lumpectomy and radiation) in octogenarians with breast cancer. Medical records of women (ages 80-89) who received treatment for breast cancer from 1984 through 1994 were reviewed. All patients were stage T1 or T2, and none had palpable lymph nodes. The recurrence rate, disease-free interval, and death rate for both groups were compared. Of the 41 patients representing 43 minor surgeries, 12 per cent (5 of 41) of patients developed recurrence, all of which were related to the primary breast tumor. The mean disease-free interval was 28.6 +/- 24.7 months (range, 6-65). Forty-six per cent (18 of 39) of patients died, 10 per cent (4 of 39) from recurrence and metastatic disease from breast cancer and 36 per cent (14 of 39) from other causes. Of those who underwent extensive treatment, 14.6 per cent (7 of 48) of patients experienced recurrence, all related to the primary breast tumor. The mean disease-free interval was 24.0 +/- 21.9 months (range, 2-71). Forty-eight per cent (23 of 48) of patients died, 10 per cent (5 of 48) from recurrence and metastatic disease from breast cancer and 37 per cent (18 of 48) from other causes. None of the differences between the minor surgery versus extensive treatment groups were statistically significant. The recurrence rate, disease-free interval, and death rate from recurrent disease are similar for patients undergoing minor surgery compared with those undergoing extensive treatment.

The URA5 gene is necessary for histoplasma capsulatum growth during infection of mouse and human cells

The Histoplasma capsulatum URA5 gene, which has recently been cloned and disrupted by allelic replacement, encodes orotidine-5'-monophosphate pyrophosphorylase. Inactivation of URA5 by either targeted or UV mutagenesis results in disruption of the pyrimidine biosynthetic pathway and uracil auxotrophy. We examined the effect of uracil auxotrophy due to a ura5 mutation on H. capsulatum virulence in both cell culture and whole-animal models. Uracil auxotrophs of two H. capsulatum restriction fragment length polymorphism classes were found to be avirulent in cultured murine and human cells, as well as in mice. Moreover, virulence could be restored either by supplying a functional URA5 gene in trans or by supplying exogenous uracil during infection in vitro. These experiments demonstrate that the pyrimidine biosynthetic pathway is essential for H. capsulatum growth and virulence.

Testimony psychotherapy in Bosnian refugees: a pilot study

OBJECTIVE

The authors sought to describe the use of the testimony method of psychotherapy in a group of traumatized adult refugees from genocide in Bosnia-Herzegovina.

METHOD

The subjects were 20 Bosnian refugees in Chicago who gave written informed consent to participate in a case series study of testimony psychotherapy. All subjects received testimony psychotherapy, averaging six sessions, approximately 90 minutes, weekly or biweekly. Subjects received standardized instruments for posttraumatic stress disorder (PTSD), depression, traumatic events, global functioning, and prior psychiatric history. The instruments were administered before treatment, at the conclusion of the treatment, and at the 2- and 6-month follow-ups.

RESULTS

The posttreatment assessments demonstrated significant decreases in the rate of PTSD diagnosis, PTSD symptom severity, and the severity of reexperiencing, avoidance, and hyperarousal symptom clusters. Depressive symptoms demonstrated a significant decrease, and there was a significant increase in scores on the Global Assessment of Functioning Scale. Two-month and 6-month follow-up assessments demonstrated further significant decreases in all symptoms and an increase in scores on the Global Assessment of Functioning Scale.

CONCLUSIONS

This pilot study provides preliminary evidence that testimony psychotherapy may lead to improvements in PTSD and depressive symptoms, as well as to improvement of functioning, in survivors of state-sponsored violence.

Vbeta4(+) T cells promote clearance of infection in murine pulmonary histoplasmosis

T cells are essential for controlling infection with Histoplasma capsulatum. Because the T cell receptor is vital for transducing the biological activities of these cells, we sought to determine if exposure to this fungus induced an alteration in the Vbeta repertoire in lungs of C57BL/6 mice infected intranasally. Vbeta2(+) cells were elevated on day 3 after infection; Vbeta4(+) cells were higher than controls on days 7, 10, and 14 after infection. Vbeta10(+) cells were increased on days 14 and 21, and Vbeta11(+) exceeded controls only on day 14. We investigated the clonality and function of Vbeta4(+) cells because their expansion transpired during the critical time of infection, that is, when cellular immunity is activated. Sequence analysis demonstrated preferential use of a restricted set of sequences in the complementarity-determining region 3. Elimination of Vbeta4(+) cells from mice impaired their ability to resolve infection. In contrast, depletion of Vbeta7(+) cells, the abundance of which was similar to that of Vbeta4(+), did not alter elimination of the fungus. The identification of clonotypes of Vbeta4(+) cells suggests that a few antigenic determinants may drive proliferation of this subset, which is necessary for optimal clearance.