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Children's Hospital Foundation

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Research output, citation impact, and the most-cited recent papers from Children's Hospital Foundation (United States). Aggregated across the NobleBlocks index of 300M+ scholarly works.

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485
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Children's Hospital Foundation

Top-cited papers from Children's Hospital Foundation

Evaluation of Myc E-Box Phylogenetic Footprints in Glycolytic Genes by Chromatin Immunoprecipitation Assays
Jung‐whan Kim, Karen Zeller, Yunyue Wang, Anil G. Jegga +3 more
2004· Molecular and Cellular Biology377doi:10.1128/mcb.24.13.5923-5936.2004

Prediction of gene regulatory sequences using phylogenetic footprinting has advanced considerably but lacks experimental validation. Here, we report whether transcription factor binding sites predicted by dot plotting or web-based Trafac analysis could be validated by chromatin immunoprecipitation assays. MYC overexpression enhances glycolysis without hypoxia and hence may contribute to altered tumor metabolism. Because the full spectrum of glycolytic genes directly regulated by Myc is not known, we chose Myc as a model transcription factor to determine whether it binds target glycolytic genes that have conserved canonical Myc binding sites or E boxes (5'-CACGTG-3'). Conserved canonical E boxes in ENO1, HK2, and LDHA occur in 31- to 111-bp islands with high interspecies sequence identity (>65%). Trafac analysis revealed another region in ENO1 that corresponds to a murine region with a noncanonical E box. Myc bound all these conserved regions well in the human P493-6 B lymphocytes. We also determined whether Myc could bind nonconserved canonical E boxes found in the remaining human glycolytic genes. Myc bound PFKM, but it did not significantly bind GPI, PGK1, and PKM2. Binding to BPGM, PGAM2, and PKLR was not detected. Both GAPD and TPI1 do not have conserved E boxes but are induced and bound by Myc through regions with noncanonical E boxes. Our results indicate that Myc binds well to conserved canonical E boxes, but not nonconserved E boxes. However, the binding of Myc to unpredicted genomic regions with noncanonical E boxes reveals a limitation of phylogenetic footprinting. In aggregate, these observations indicate that Myc is an important regulator of glycolytic genes, suggesting that MYC plays a key role in a switch to glycolytic metabolism during cell proliferation or tumorigenesis.

Urokinase-type plasminogen activator is effective in fibrin clearance in the absence of its receptor or tissue-type plasminogen activator.
Thomas H. Bugge, Matthew J. Flick, Mary Jo S. Danton, Cynthia C. Daugherty +4 more
1996· Proceedings of the National Academy of Sciences276doi:10.1073/pnas.93.12.5899

The availability of gene-targeted mice deficient in the urokinase-type plasminogen activator (uPA), urokinase receptor (uPAR), tissue-type plasminogen activator (tPA), and plasminogen permits a critical, genetic-based analysis of the physiological and pathological roles of the two mammalian plasminogen activators. We report a comparative study of animals with individual and combined deficits in uPAR and tPA and show that these proteins are complementary fibrinolytic factors in mice. Sinusoidal fibrin deposits are found within the livers of nearly all adult mice examined with a dual deficiency in uPAR and tPA, whereas fibrin deposits are never found in livers collected from animals lacking uPAR and rarely detected in animals lacking tPA alone. This is the first demonstration that uPAR has a physiological role in fibrinolysis. However, uPAR-/-/tPA-/- mice do not develop the pervasive, multi-organ fibrin deposits, severe tissue damage, reduced fertility, and high morbidity and mortality observed in mice with a combined deficiency in tPA and the uPAR ligand, uPA. Furthermore, uPAR-/-/tPA-/- mice do not exhibit the profound impairment in wound repair seen in uPA-/-/tPA-/- mice when they are challenged with a full-thickness skin incision. These results indicate that plasminogen activation focused at the cell surface by uPAR is important in fibrin surveillance in the liver, but that uPA supplies sufficient fibrinolytic potential to clear fibrin deposits from most tissues and support wound healing without the benefit of either uPAR or tPA.

Newly Recognized Myxoviruses from Children with Respiratory Disease
Robert M. Chanock, Robert H. Parrott, Katherine Cook, B. E. Andrews +4 more
1958· New England Journal of Medicine274doi:10.1056/nejm195801302580502

THE present study was designed to investigate the viral etiology of respiratory illness in infants and young children. One of the technics employed for isolation of the virus was the recently described hemadsorption method of Vogel and Shelokov.1 , 2 With this technic, several strains of Asian influenza A virus were isolated, but the majority of agents recovered were not influenza A, B or C. The noninfluenza agents appear to comprise two newly recognized groups of myxoviruses,3 probably responsible for a segment of common respiratory illnesses in children. Their properties, serologic characterization and the evidence bearing upon their relation to disease will . . .

Practice guideline summary: Use of fMRI in the presurgical evaluation of patients with epilepsy
Jerzy P. Szaflarski, David Gloss, Jeffrey R. Binder, William D. Gaillard +4 more
2017· Neurology243doi:10.1212/wnl.0000000000003532

OBJECTIVE: To assess the diagnostic accuracy and prognostic value of functional MRI (fMRI) in determining lateralization and predicting postsurgical language and memory outcomes. METHODS: An 11-member panel evaluated and rated available evidence according to the 2004 American Academy of Neurology process. At least 2 panelists reviewed the full text of 172 articles and selected 37 for data extraction. Case reports, reports with <15 cases, meta-analyses, and editorials were excluded. RESULTS AND RECOMMENDATIONS: The use of fMRI may be considered an option for lateralizing language functions in place of intracarotid amobarbital procedure (IAP) in patients with medial temporal lobe epilepsy (MTLE; Level C), temporal epilepsy in general (Level C), or extratemporal epilepsy (Level C). For patients with temporal neocortical epilepsy or temporal tumors, the evidence is insufficient (Level U). fMRI may be considered to predict postsurgical language deficits after anterior temporal lobe resection (Level C). The use of fMRI may be considered for lateralizing memory functions in place of IAP in patients with MTLE (Level C) but is of unclear utility in other epilepsy types (Level U). fMRI of verbal memory or language encoding should be considered for predicting verbal memory outcome (Level B). fMRI using nonverbal memory encoding may be considered for predicting visuospatial memory outcomes (Level C). Presurgical fMRI could be an adequate alternative to IAP memory testing for predicting verbal memory outcome (Level C). Clinicians should carefully advise patients of the risks and benefits of fMRI vs IAP during discussions concerning choice of specific modality in each case.

Practical Aspects of Conducting Large-Scale Functional Magnetic Resonance Imaging Studies in Children
Anna W. Byars, Scott K. Holland, Richard H. Strawsburg, Wendy Bommer +3 more
2002· Journal of Child Neurology212doi:10.1177/08830738020170122201

The potential benefits of functional magnetic resonance imaging (MRI) for the investigation of normal development have been limited by difficulties in its use with children. We describe the practical aspects, including failure rates, involved in conducting large-scale functional MRI studies with normal children. Two hundred and nine healthy children between the ages of 5 and 18 years participated in a functional MRI study of language development. Reliable activation maps were obtained across the age range. Younger children had significantly higher failure rates than older children and adolescents. It is concluded that it is feasible to conduct large-scale functional MRI studies of children as young as 5 years old. These findings can be used by other research groups to guide study design and plans for recruitment of young subjects.

A Double-Blind Evaluation of Ketorolac Tromethamine Versus Acetaminophen in Pediatric Tonsillectomy
Lynn M. Rusy, Constance S. Houck, Lorna J. Sullivan, Laurie A. Ohlms +3 more
1995· Anesthesia & Analgesia200doi:10.1097/00000539-199502000-00004

The study was designed to compare intravenous ketorolac to rectal acetaminophen for analgesia and bleeding in pediatric patients undergoing tonsillectomy. We studied 50 patients, aged 2-15 yr undergoing tonsillectomy with or without adenoidectomy. In a randomized, prospective double-blind fashion, patients were assigned to receive either ketorolac (1 mg/kg) or rectal acetaminophen (35 mg/kg). Bleeding was evaluated by measuring intraoperative blood loss and noting extra measures required to obtain hemostasis. Bleeding times were also measured before and during surgery. Pain was evaluated using a standard objective pain score for the first 3 h. Persistent pain was treated with morphine, acetaminophen, and codeine and recorded for 24 h. Blood for determination of acetaminophen levels was drawn at 20 and 40 min after the administration of study drugs. Pain scores were not significantly different between the ketorolac and acetaminophen groups. The majority of patients in both groups required additional opioid in the postoperative period. Acetaminophen levels were all less than the therapeutic range. Intraoperative bleeding times were normal in all patients, but blood loss was significantly higher in the ketorolac group (2.67 mL/kg) compared to the acetaminophen group (1.44 mL/kg), P = 0.025. Significantly more measures to achieve hemostasis were required in the ketorolac group (P = 0.012). We conclude that ketorolac is no more effective than high-dose rectal acetaminophen for analgesia in the patient undergoing tonsillectomy. Hemostasis during tonsillectomy was significantly more difficult to achieve in patients receiving ketorolac.

Structure and genetics of the partially duplicated gene RP located immediately upstream of the complement C4A and the C4B genes in the HLA class III region. Molecular cloning, exon-intron structure, composite retroposon, and breakpoint of gene duplication.
Like Shen, Lai‐Chu Wu, Salih Şanlıoğlu, Ruoyi Chen +4 more
1994· Journal of Biological Chemistry193doi:10.1016/s0021-9258(17)37217-4

The correlation of many HLA-associated autoimmune and genetic diseases with the polymorphic complement C4 genes may be attributed to the presence of disease susceptibility genes in the close proximity of C4. We have cloned and characterized a pair of partially duplicated genes, RP1 and RP2, located 611 base pairs upstream of the human C4A and C4B genes, respectively. The putative RP protein, consisting of 364 amino acid residues, is basic and highly hydrophilic. There is a bipartite nuclear localization signal at residues 114-131 and therefore RP may be a nuclear protein. Northern blot analysis suggested that RP is ubiquitously expressed. The 5' region of the RP1 gene is CpG rich, which is a characteristic of housekeeping genes. The RP1 gene contains nine exons. Located in the fourth intron is a cluster of Alu elements, and a newly defined composite retroposon SVA with a SINE, multiple copies of GC-rich VNTRs and an Alu element altogether enclosed by direct terminal repeats. Members of SVA are also present in the complement C2 gene located about 20 kilobases upstream of RP1 in the HLA and in the cytochrome CYP1A1 gene. Determination of the DNA sequences for RP2 from two different HLA haplotypes revealed identical hybrid sequences which resulted from fusion of RP with the tenascin-like Gene X and truncation of the 5' regions of both genes. Cumulative data suggest that the four tandemly arranged genes RP, complement C4, steroid 21-hydroxylase (CYP21), and Gene X altogether form a modular structure, RCCX. The number of RCCX modules varies from one to three or more in the population. Absence of the truncated genes RP2 and Gene XA have been detected in genomes with single RCCX modules. Duplication of the RCCX modules probably occurred before the speciation of great apes and humans as they contain the same breakpoint region of RP and Gene X gene duplication.

Modular Variations of the Human Major Histocompatibility Complex Class III Genes for Serine/Threonine Kinase RP, Complement Component C4, Steroid 21-Hydroxylase CYP21, and Tenascin TNX (the RCCX Module)
Zhenyu Yang, Anna R. Mendoza, Thomas R. Welch, William B. Zipf +1 more
1999· Journal of Biological Chemistry183doi:10.1074/jbc.274.17.12147

The frequent variations of human complement component C4 gene size and gene numbers, plus the extensive polymorphism of the proteins, render C4 an excellent marker for major histocompatibility complex disease associations. As shown by definitive RFLPs, the tandemly arranged genes RP, C4, CYP21, and TNX are duplicated together as a discrete genetic unit termed the RCCX module. Duplications of the RCCX modules occurred by the addition of genomic fragments containing a long (L) or a short (S) C4 gene, a CYP21A or a CYP21B gene, and the gene fragments TNXA and RP2. Four major RCCX structures with bimodular L-L, bimodular L-S, monomodular L, and monomodular S are present in the Caucasian population. These modules are readily detectable by TaqI RFLPs. The RCCX modular variations appear to be a root cause for the acquisition of deleterious mutations from pseudogenes or gene segments in the RCCX to their corresponding functional genes. In a patient with congenital adrenal hyperplasia, we discovered a TNXB-TNXA recombinant with the deletion of RP2-C4B-CYP21B. Elucidation of the DNA sequence for the recombination breakpoint region and sequence analyses yielded definitive proof for an unequal crossover between TNXA from a bimodular chromosome and TNXB from a monomodular chromosome.

Murine Eotaxin-2: A Constitutive Eosinophil Chemokine Induced by Allergen Challenge and IL-4 Overexpression
Nives Zimmermann, Simon P. Hogan, Anil Mishra, Eric B. Brandt +4 more
2000· The Journal of Immunology176doi:10.4049/jimmunol.165.10.5839

The generation of tissue eosinophilia is governed in part by chemokines; initial investigation has identified three chemokines in the human genome with eosinophil selectivity, referred to as eotaxin-1, -2, and -3. Elucidation of the role of these chemokines is dependent in part upon analysis of murine homologues; however, only one murine homologue, eotaxin-1, has been identified. We now report the characterization of the murine eotaxin-2 cDNA, gene and protein. The eotaxin-2 cDNA contains an open reading frame that encodes for a 119-amino acid protein. The mature protein, which is predicted to contain 93 amino acids, is most homologous to human eotaxin-2 (59.1% identity), but is only 38.9% identical with murine eotaxin-1. Northern blot analysis reveals three predominant mRNA species and highest constitutive expression in the jejunum and spleen. Additionally, allergen challenge in the lung with Aspergillus fumigatus or OVA revealed marked induction of eotaxin-2 mRNA. Furthermore, eotaxin-2 mRNA was strongly induced by both transgenic over-expression of IL-4 in the lung and administration of intranasal IL-4. Analysis of eotaxin-2 mRNA expression in mice transgenic for IL-4 but genetically deficient in STAT-6 revealed that the IL-4-induced expression was STAT-6 dependent. Recombinant eotaxin-2 protein induced dose-dependent chemotactic responses on murine eosinophils at concentrations between 1-1000 ng/ml, whereas no activity was displayed on murine macrophages or neutrophils. Functional analysis of recombinant protein variants revealed a critical role for the amino terminus. Thus, murine eotaxin-2 is a constitutively expressed eosinophil chemokine likely to be involved in homeostatic, allergen-induced, and IL-4-associated immune responses.

Treatment of Congenital Osteopetrosis with High-Dose Calcitriol
Lyndon Key, David L. Carnes, Sessions Cole, Marijke Holtrop +4 more
1984· New England Journal of Medicine173doi:10.1056/nejm198402163100701

We administered high doses of calcitriol (up to 32 micrograms per day) to an infant with malignant osteopetrosis, in an attempt to stimulate bone resorption. The patient was placed on a low-calcium diet to prevent hypercalcemia. Measures of bone turnover increased during calcitriol therapy; hydroxyproline excretion rose from 140 to 1358 micrograms per milligram of creatinine per 24 hours, with parallel increases in the ratio of calcium to creatinine in the urine, urinary gamma-carboxyglutamic acid, serum osteocalcin, and serum alkaline phosphatase. A pretreatment bone-biopsy specimen contained no osteoclasts with ruffled borders, a feature of active osteoclasts. After 11 days of calcitriol, ruffled borders were noted. After three months, numerous osteoclasts with ruffled borders and associated bony disruption were evident. Before therapy, the patient's monocytes were incapable of in vitro bone resorption, but after calcitriol, their resorptive capacity was increased to 3.3 times control levels. These data demonstrate that calcitriol increased bone mineral and matrix turnover in our patient. However, during the three months of calcitriol therapy there was only slight clinical improvement in her severe disease. Early and sustained treatment with calcitriol may be useful in osteopetrosis.

COMPARATIVE EPIDEMIOLOGY OF TWO ROTAVIRUS SEROTYPES AND OTHER VIRAL AGENTS ASSOCIATED WITH PEDIATRIC GASTROENTERITIS
Carl D. Brandt, H. W. Kim, R H Yolken, A. Z. Kapikian +4 more
1979· American Journal of Epidemiology141doi:10.1093/oxfordjournals.aje.a112809

Human rotavirus (HRV) type 1 or 2, adenovirus, or non-cultivatable 27 nm virus-like particles were demonstrated by electron microscopy and/or rotavirus ELISA in fecal samples from 45.5% of 604 gastroenteritis inpatients, 25.0% of 200 gastroenteritis outpatients and 6.0% of 812 control subjects, all sampled at Children's Hospital National Medical Center. Washington, DC. Rotaviruses were the most common pathogens detected as 39% and 22% of gastroenteritis inpatients and outpatients, respectively, shed HRV. About three-fourths of the rotaviruses were type 2, which was prevalent during five successive epidemic years from January, 1974, through June, 1978. HRV type 1 was detected in the last four successive epidemic years and represented nearly half of the HRV infections observed among gastroenteritis inpatients during the year 1977--1978. Both rotavirus serotypes were detected most often in the month of January, when 71% of 123 gastroenteritis inpatients and 62% of 34 gastroenteritis outpatients shed one of these viruses. Uncultivatable adenoviruses were detected significantly more frequently in stools from patients with gastroenteritis (3.9%) than from control subjects (0.6%), suggesting that these viruses played a role in acute enteric disease. The frequency of detection of 27 nm particles was not significantly different in gastroenteritis and control patients. Numerically, HRV infection was detected most often in gastroenteritis inpatients who were 10 through 12 months of age. The group of gastroenteritis inpatients with the highest percentage of HRV infection was 13 through 15 months of age. The excess of type 2 HRV infection relative to type 1 infection was especially large in those aged 7 through 24 months. Lower socioeconomic status or greater crowding appeared to be associated with the occurrence of rotavirus infection earlier in life and earlier in the epidemic year.

Treatment of newly diagnosed children and adolescents with acute myeloid leukemia: a Childrens Cancer Group study.
Robert J. Wells, William G. Woods, Jonathan D. Buckley, Lorrie F. Odom +4 more
1994· Journal of Clinical Oncology131doi:10.1200/jco.1994.12.11.2367

PURPOSE The objectives of this study were to determine if the addition of etoposide, thioguanine, and dexamethasone to daunorubicin and cytarabine (five-drug regimen) during induction would improve remission induction rates and survival of children with acute myeloid leukemia (AML) when compared with the standard regimen of cytarabine and daunorubicin (7 + 3) and whether allogeneic bone marrow transplantation (BMT) or intensive chemotherapy consolidation with or without maintenance would give a superior outcome. PATIENTS AND METHODS A total of 591 assessable children with AML entered Childrens Cancer Group (CCG) trial 213 between January 1986 and February 1989. The status of patients as of September 1, 1992 forms the basis of this report. The results were compared with previous AML studies. RESULTS The projected survival rate of all patients at 5 years is 39% (event-free survival [EFS] rate, 31%), which is superior to that of the prior CCG study (P = .01). The induction rate was 79% for 7 + 3 and 76% for the five-drug regimen (not significant). Comparisons of BMT to chemotherapy favored BMT, but these differences do not always reach statistical significance (eg, 5-year disease-free survival [DFS] rate, 46% v 38% [P = .06] with donor available and 54% v 37% [P = .002] if treated according to protocol intent). No benefit for maintenance therapy was found and, in some comparisons, it was inferior to discontinuation of therapy (5-year survival rate, 46% v 68%, P &lt; .01). CONCLUSION The 5-year EFS rate of patients with AML is 31% and has improved. The five-drug induction regimen is no better than standard induction, BMT appears superior to chemotherapy, and maintenance therapy was not beneficial.

Neonatal Thrombocytopenia Associated with Ante-Partum Administration of Thiazide Drugs
Salud U. Rodriguez, Sanford Leikin, Marilyn C. Hiller
1964· New England Journal of Medicine128doi:10.1056/nejm196404232701706

WITHIN the last several years there have been scattered reports of purpura occurring in patients receiving chlorothiazide and hydrochlorothiazide.1 2 3 4 5 6 7 Since the conditions for which these drugs are used occur chiefly in the older age groups, purpura in association with the administration of the drugs mentioned above has not been reported in the pediatric literature.Recently, we observed a group of newborn infants with thrombocytopenia whose mothers had neither a platelet deficiency nor detectable anti-platelet antibody in the serum. However, these mothers had received either chlorothiazide, hydrochlorothiazide or methyclothiazide during pregnancy, and the thrombocytopenia in their infants was possibly due to . . .

The effect of enzyme replacement therapy on bone crisis and bone pain in patients with type 1 Gaucher disease
Joel Charrow, Brian Dulisse, GA Grabowski, NJ Weinreb
2007· Clinical Genetics124doi:10.1111/j.1399-0004.2007.00769.x

The effect of enzyme replacement therapy (ERT) on bone crisis and bone pain was investigated in patients with Gaucher disease (GD) type 1 followed over 4 years. Data from the International Collaborative Gaucher Group Gaucher Registry were used. Only patients with bone crisis and/or bone pain data for 1 year prior to ERT, and for each of 3 years after the start of ERT, were included. Bone crises were reported in 17% of patients during the year before starting ERT. The frequencies of bone crises decreased to 5%, <1% and 3% for 1, 2, and 3 years after initiation of treatment, respectively (p < 0.0001). Bone pain followed a similar pattern of response. Bone pain was reported in 49% of patients the year before treatment and decreased to 30% in the first year, 29% in the second year, and 30% in the third year of ERT (p < 0.0001). ERT is associated with a reduction in bone crisis and bone pain in patients with GD type 1 . This study shows that significant improvements in symptoms of skeletal disease are achievable clinical outcomes and treatment goals in GD type 1.

Controlled Study of Child Health Supervision: Behavioral Results
Margaret F. Gutelius, Arthur D. Kirsch, Sally Macdonald, Marion Riddick Brooks +1 more
1977· PEDIATRICS117doi:10.1542/peds.60.3.294

Extensive child health supervision, with emphasis on counseling and anticipatory guidance, was provided for the first three years of life to an experimental series of 47 normal first-born black infants from low-income families living in the environs of Children's Hospital in Washington, D.C. The mothers were unmarried schoolgirls in normal physical and mental health. A control series consisted of 48 similar mother-child dyads from the same area. Data were collected, in part by an outside evaluator, at yearly intervals on both experimental and control series in a form suitable for coding on computer cards. Comparison of differences in behavioral results between the two series showed statistically significant findings in favor of the experimental children, as well as numerous favorable trends during the first six years of life. Positive effects became evident in diet and eating, habits, in some developmental problems of growing up (such as toilet training), and in certain abstract qualities including self-confidence. Significant differences were also noted between the experimental and control mothers for various child rearing practices and personality characteristics. No significant difference or trend favored the control series. We believe that a causal relationship existed between the intervention and at least some of the significant findings.

CLINICAL AND IMMUNOLOGICAL RESPONSE OF INFANTS AND CHILDREN TO ADMINISTRATION OF LOW- TEMPERATURE ADAPTED RESPIRATORY SYNCYTIAL VIRUS
Hyun Wha Kim, Julita O. Arrobio, Gloria Pyles, Carl D. Brandt +3 more
1971· PEDIATRICS116doi:10.1542/peds.48.5.745

Thirty-nine infants and children 6 months to 13 years of age received live 26°C grown respiratory syncytical (RS) virus (strain A2) by the oropharyngeal and nasopharyngeal route. RS virus was recovered from 22 individuals and 17 of these showed a significant rise in CF and/or plaque reduction serum antibody. Twelve of those from whom virus was recovered and an additional three from whom virus was not recovered showed a threefold or greater rise of RS nasal neutralizing activity. Thus 26 of the total showed some evidence of having been infected with the ES strain. The rate of infection was significantly greater in infants and children under 2 years of age than in older children. Infection in individuals older than 8 months of age was asymptomatic. Three infants infected with the vaccine strain had relatively minor respiratory tract illness. The findings from this study indicate that the low-temperature adapted virus retains a low level of virulence which is expressed only in individuals undergoing primary infection. Nonetheless, these studies have shown that it is possible to induce local and systemic immune responses to RS virus by means other than fully virulent natural infection.

Mice Lacking Skeletal Muscle Actin Show Reduced Muscle Strength and Growth Deficits and Die during the Neonatal Period
Kelly Crawford, Robert W. Flick, L. Close, Daniel A. Shelly +4 more
2002· Molecular and Cellular Biology113doi:10.1128/mcb.22.16.5887-5896.2002

All four of the muscle actins (skeletal, cardiac, vascular, and enteric) in higher vertebrates show distinct expression patterns and display highly conserved amino acid sequences. While it is hypothesized that each of the muscle isoactins is specifically adapted to its respective tissue and that the minor variations among them have developmental and/or physiological relevance, the exact functional and developmental significance of these proteins remains largely unknown. In order to begin to assess these issues, we disrupted the skeletal actin gene by homologous recombination. All mice lacking skeletal actin die in the early neonatal period (day 1 to 9). These null animals appear normal at birth and can breathe, walk, and suckle, but within 4 days, they show a markedly lower body weight than normal littermates and many develop scoliosis. Null mice show a loss of glycogen and reduced brown fat that is consistent with malnutrition leading to death. Newborn skeletal muscles from null mice are similar to those of wild-type mice in size, fiber type, and ultrastructural organization. At birth, both hemizygous and homozygous null animals show an increase in cardiac and vascular actin mRNA in skeletal muscle, with no skeletal actin mRNA present in null mice. Adult hemizygous animals show an increased level of skeletal actin mRNA in hind limb muscle but no overt phenotype. Extensor digitorum longus (EDL) muscle isolated from skeletal-actin-deficient mice at day 2 to 3 showed a marked reduction in force production compared to that of control littermates, and EDL muscle from hemizygous animals displayed an intermediate force generation. Thus, while increases in cardiac and vascular smooth-muscle actin can partially compensate for the lack of skeletal actin in null mice, this is not sufficient to support adequate skeletal muscle growth and/or function.

A stable cell line carrying adenovirus-inducible rep and cap genes allows for infectivity titration of adeno-associated virus vectors.
K. Reed Clark, Frosso Voulgaropoulou, Paul Johnson
1996· PubMed111

Adeno-associated virus (AAV) vectors are being developed for in vivo and ex vivo gene transfer to human cells. At present, widespread usage of AAV vectors is limited primarily by difficulties in generating recombinant virions on a scale sufficient for in-depth preclinical and clinical trials. However, recent work in several laboratories suggests that this technical obstacle should be overcome in the near future. As a result, it can be anticipated that the interest in AAV vectors will expand, Thus, it becomes important to develop assay systems that will permit accurate quantification of the infectivity of AAV vectors derived from a variety of sources. We have developed an assay using a cell line that expresses AAV helper functions (rep and cap) upon induction by adenovirus infection. This assay system is based on the replication of input rAAV genomes rather than transgene expression (transduction). Thus, infectivity titrations in this system yield an estimation of rAAV infectious particles irrespective of the promoter or transgene present in the vector genome. Moreover, this assay method is more sensitive than conventional methods being used in other laboratories.

A Possible Autoimmune Basis for Addison's Disease in Three Siblings, One with Idiopathic Hypoparathyroidism, Pernicious Anemia and Superficial Moniliasis
Wellington Hung, Claude J. Migeon, Robert H. Parrott
1963· New England Journal of Medicine107doi:10.1056/nejm196309262691303

FAMILIAL Addison's disease is an uncommon entity. In 1959 Meakin, Nelson and Thorn1 reviewed the literature and found 5 cases of familial Addison's disease documented by steroid studies or autopsy findings,2 3 4 5 6 and reported another case. Since that time 4 additional cases fulfilling their criteria have been reported.7 8 9 10 The association of superficial moniliasis, idiopathic hypoparathyroidism and Addison's disease is even rarer, only 6 cases being found in the literature.11 12 13 14 15 The purpose of this report is to describe a family in which Addison's disease was present in 3 siblings, 1 of whom also had superficial moniliasis, idiopathic hypoparathyroidism and pernicious anemia. We . . .

Passive Immunotherapy in Simian Immunodeficiency Virus-Infected Macaques Accelerates the Development of Neutralizing Antibodies
Nancy L. Haigwood, David C. Montefiori, William F. Sutton, Janela McClure +4 more
2004· Journal of Virology104doi:10.1128/jvi.78.11.5983-5995.2004

Passively transferred neutralizing antibodies can block lentivirus infection, but their role in postexposure prophylaxis is poorly understood. In this nonhuman-primate study, the effects of short-term antibody therapy on 5-year disease progression, virus load, and host immunity were explored. We reported previously that postinfection passive treatment with polyclonal immune globulin with high neutralizing titers against SIVsmE660 (SIVIG) significantly improved the 67-week health of SIVsmE660-infected Macaca mulatta macaques. Four of six treated macaques maintained low or undetectable levels of virus in plasma, compared with one of ten controls, while two rapid progressors controlled viremia only as long as the SIVIG was present. SIVIG treatment delayed the de novo production of envelope (Env)-specific antibodies by 8 weeks (13). We show here that differences in disease progression were also significant at 5 years postinfection, excluding rapid progressors (P = 0.05). Macaques that maintained </=10(3) virus particles per ml of plasma and </=30 infectious virus particles per 10(6) mononuclear cells from peripheral blood and lymph nodes had delayed disease onset. All macaques that survived beyond 18 months had measurable Gag-specific CD8(+) cytotoxic T cells, regardless of treatment. Humoral immunity in survivors beyond 20 weeks was strikingly different in the SIVIG and control groups. Despite a delay in Env-specific binding antibodies, de novo production of neutralizing antibodies was significantly accelerated in SIVIG-treated macaques. Titers of de novo neutralizing antibodies at week 12 were comparable to levels achieved in controls only by week 32 or later. Acceleration of de novo simian immunodeficiency virus immunity in the presence of passively transferred neutralizing antibodies is a novel finding with implications for postexposure prophylaxis and vaccines.