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B Connolly

Publications and source records attributed to B Connolly.

At least 37 records · Page 2Linked to original sources
PubMed2001

Ratios of multijet Cross Sections in p p collisions at radical(s) = 1.8 TeV.

We report on a study of the ratio of inclusive three-jet to inclusive two-jet production cross sections as a function of total transverse energy in p&pmacr; collisions at a center-of-mass energy sqrt[s] = 1.8 TeV, using data collected with the D0 detector during the 1992-1993 run of the Fermilab Tevatron Collider. The measurements are used to deduce preferred renormalization scales in perturbative O(alpha(3)(s)) QCD calculations in modeling soft-jet emission.

Journal Article↗
PubMed2001

Inclusive jet production in pp(macro) collisions.

We report a new measurement of the pseudorapidity (eta) and transverse-energy ( E(T)) dependence of the inclusive jet production cross section in pp(macro) collisions at square root of s = 1.8 TeV using 95 pb(-1) of data collected with the D0 detector at the Fermilab Tevatron. The differential cross section d(2)sigma/(dE(T)d eta) is presented up to eta = 3, significantly extending previous measurements. The results are in good overall agreement with next-to-leading order predictions from QCD and indicate a preference for certain parton distribution functions.

Journal Article↗
PubMed2001

Search for large extra dimensions in dielectron and diphoton production.

We report a search for effects of large extra spatial dimensions in pp collisions at a center-of-mass energy of 1.8 TeV with the D0 detector, using events containing a pair of electrons or photons. The data are in good agreement with the expected background and do not exhibit evidence for large extra dimensions. We set the most restrictive lower limits to date, at the 95% C.L. on the effective Planck scale between 1.0 and 1.4 TeV for several formalisms and numbers of extra dimensions.

Journal Article↗
PubMed2001

Secretion of the novel Trichinella protein TSJ5 by T. spiralis and T. pseudospiralis muscle larvae.

The Trichinella tsJ5 gene is preferentially expressed in muscle larvae of Trichinella spiralis and encodes a novel protein. Previous observations have shown tsJ5 to be expressed at higher levels in encapsulating species than in non-encapsulating species and down-regulation of gene expression in T. pseudospiralis to be correlated with a lower protein abundance in the muscle larva of this species. In the present study we have determined the full-length cDNA sequence of the tsJ5 homologue in T. pseudospiralis (tpJ5). Antigens recognised by an anti-J5 antibody are found on the cuticular surface of both T. spiralis and T. pseudospiralis muscle larvae, as well as in the body wall muscle. We show that both the TSJ5 and TPJ5 proteins are found in the excretory/secretory fractions collected from muscle larva cultured in vitro and that despite the absence of a typical N-terminal signal sequence, secretion of pTSJ5 is mediated through the classical ER/Golgi secretory pathway.

Amino Acid Sequence↗
PubMed2000

Measurement of the W-->taunu production cross section in pp collisions at square root s=1.8 TeV.

We report on a measurement of sigma(pp-->W+X)B(W-->taunu) in pp collisions at sqrt[s]=1.8 TeV at the Fermilab Tevatron. The measurement is based on an integrated luminosity (lum) of 18 pb-1 of data collected with the D0 detector during 1994-1995. We find that sigma(pp-->W+X)B(W-->taunu)=2.22+/-0.09 (stat)+/-0. 10 (syst)+/-0.10 (lum) nb. Lepton universality predicts that the ratio of the tau and electron electroweak charged current couplings to the W boson, gWtau/gWe, be unity. We find gWtau/gWe=0.980+/-0.031, in agreement with lepton universality.

Journal Article↗
PubMed2000

Probing Balitsky-Fadin-Kuraev-Lipatov dynamics in the dijet cross section at large rapidity intervals in pp collisions at sqrt[s]=1800 and 630 GeV.

Inclusive dijet production at large pseudorapidity intervals (Deltaeta) between the two jets has been suggested as a regime for observing Balitsky-Fadin-Kuraev-Lipatov (BFKL) dynamics. We have measured the dijet cross section for large Deltaeta in pp collisions at sqrt[s]=1800 and 630 GeV using the D0 detector. The partonic cross section increases strongly with the size of Deltaeta. The observed growth is even stronger than expected on the basis of BFKL resummation in the leading logarithmic approximation. The growth of the partonic cross section can be accommodated with an effective BFKL intercept of alphaBFKL(20 GeV)=1.65+/-0.07.

Journal Article↗
PubMed2000

Overexpression of M68/DcR3 in human gastrointestinal tract tumors independent of gene amplification and its location in a four-gene cluster.

Fas-mediated apoptosis is an important regulator of cell survival, and abnormalities in this system have been shown to result in a number of human pathological conditions. A secreted member of the tumor necrosis factor receptor superfamily, DcR3, was recently reported to be amplified in human lung and colon cancers as a negative regulator of Fas-mediated apoptosis. We identified this gene, which we call M68. M68 genomic DNA, mRNA, and protein levels were examined in a series of human gastrointestinal tract tumors. Using M68 immunohistochemistry and a scoring system similar to that used for HER-2/neu, we found that M68 protein was overexpressed in 30 of 68 (44%) human adenocarcinomas of the esophagus, stomach, colon, and rectum. Tumors examined by Northern blot revealed M68 mRNA highly elevated in a similar fraction of primary tumors from the same gastrointestinal tract regions, as well as in the colon adenocarcinoma cell lines SW480 and SW1116. Further, we found M68 protein to be overexpressed in a substantial number of tumors in which gene amplification could not be detected by fluorescence in situ hybridization or quantitative genomic PCR, suggesting that overexpression of M68 may precede amplification in tumors. Finally, we find that M68 lies within a four-gene cluster that includes a novel helicase-like gene (NHL) related to RAD3/ERCC2, a plasma membrane Ras-related GTPase and a member of the stathmin family, amplification or overexpression of which may also contribute to cell growth and tumor progression.

ADP-Ribosylation Factors↗
PubMed2000

Jefferson fracture resulting in Collet-Sicard syndrome.

STUDY DESIGN: A case report and review of the literature. OBJECTIVE: To increase awareness of and add to the spectrum of injury that can result from Jefferson fractures, to suggest a possible mechanism of injury, and to give a brief review of pertinent facts regarding C1 burst fractures and the Collet-Sicard Syndrome. SUMMARY OF BACKGROUND DATA: To the author's knowledge, this is the first reported case of a Jefferson fracture resulting in Collet-Sicard Syndrome. It represents only the second reported case of cranial nerve palsy caused by Jefferson fracture. METHODS: A 56-year-old man sustained a C1 burst fracture in a rollover motor vehicle accident. Repeated neurologic examinations over the ensuing days revealed lesions of cranial nerves IX, X, XI, and XII on the left side. RESULTS: Two weeks of traction, 10 weeks in a halo vest, and 2 weeks in a cervical collar resulted in adequate fracture healing and almost complete resolution of the patient's neurologic symptoms. CONCLUSION: Although this is the first reported case of Collet-Sicard Syndrome caused by Jefferson fracture, the authors' review of the literature suggests that cranial nerve injuries may go unrecognized in some patients with C1 burst fractures. The importance of a thorough neurologic examination, including examination of the cranial nerves, in all cases of cervical spine injury cannot be overemphasized.

Accessory Nerve Diseases↗
PubMed2000

Efficacy and safety of radiologically placed gastrostomy tubes in paediatric haematology/oncology patients.

BACKGROUND: The treatment of malnutrition, which is of great concern in paediatric haematology/oncology patients, is fraught with problems. The goals of our study were to document the complications and assess the weight gain with gastrostomy tubes (G-tubes) in this population. PROCEDURE: Patient data were acquired by retrospective review of all haematology, oncology, and bone marrow transplant (BMT) patients (n = 44) who received radiologically placed G-tubes at our institution over a 4-year period. RESULTS: Forty-four G-tubes were placed (59% peri-BMT). At tube placement, 55% of patients were malnourished and 45% were nourished. Seventy-five percent of patients had the procedure without general anaesthetic. Localized G-tube-site infection was the most common complication (41%). Major complications occurred in 3 patients; 2 patients experienced localized peritonitis, and 1 patient developed a localized collection of pus in the abdominal wall. There were no G-tube-related deaths. At 1 month after the tube insertion, 39% of patients had gained, 54% maintained, and 7% lost weight. At 3 months, 69% had gained, 28% maintained, and 3% lost weight. There was a statistically significant weight gain from the time of the G-tube placement to both 1 month (P < 0.018) and 3 months (P < 0.0001) after G-tube placement. Patients in all diagnosis categories showed improvement from 1 to 3 months. CONCLUSIONS: We conclude that retrograde tube placement is safe and can frequently be done without general anaesthetic and that G-tube feeding effectively reverses malnutrition and prevents weight loss in this patient population.

Adolescent↗
PubMed2000

Fluoroscopic landmark for SVC-RA junction for central venous catheter placement in children.

BACKGROUND: Vascular access devices are commonly placed under image guidance. The usual aim is to place the tip at the superior vena cava-right atrial junction (SVC-RA). OBJECTIVE: To identify a radiographic landmark for the SVC-RA junction that would be useful for accurate central venous catheter tip placement in children. MATERIALS AND METHODS: Images from 56 children undergoing contrast studies of their upper limb venous systems were examined for location of the SVC-RA in relation to a radiographic landmark. RESULTS: Most patients (92.5%) showed the SVC-RA junction to lie at the sixth thoracic vertebral level or the interspace above or below. The SVC-RA junction lay lower than the right main bronchus and the notch on the right cardiomediastinal contour. CONCLUSION: The vertebral body provides a useful and radiographically visible landmark for accurate central catheter tip placement.

Adolescent↗
PubMed2000

Spontaneous reduction of intussusception: clinical spectrum, management and outcome.

BACKGROUND: To analyze the spectrum of clinical features, management and outcome of children with documented spontaneous reduction of intussusception (SROI). MATERIALS AND METHODS: Review of records of 50 children (33 boys, 17 girls; age range 11 days-15 years; mean age 4 years) with documented SROI, in whom intussusception was initially diagnosed by sonography (US) in 44, air enema in 2, and computed tomography in 4, in the 6-year period 1992-1998. RESULTS: Symptoms suggestive of intussusception were present in 21 (3 of whom had Henoch-Schönlein purpura and 4 had previous ileocolic intussusception reduced by air enema). Intussusception was an incidental finding in the other 29, in 28 of whom the finding was in the small bowel. Intussusception was limited to the small bowel in 43 and was ileocolic in 7. SROI was usually documented on US. Laparotomy performed in only 4 showed no evidence of intussusception or pathologic lead point. Outcome in all patients was favorable. CONCLUSIONS: SROI may present in symptomatic or asymptomatic children and occurs more commonly than previously reported. These intussusceptions are usually short-segment, small-bowel intussusceptions with no recognizable lead point. In asymptomatic patients, conservative observation is warranted. Intervention should be dictated by the clinical findings in symptomatic patients.

Adolescent↗
PubMed2000

Methicillin-resistant Staphylococcus aureus in a finger felon.

Methicillin-resistant Staphylococcus aureus is an increasingly prevalent nosocomial pathogen that presents therapeutic challenges. We report an incidence of methicillin-resistant S aureus in a felon. The biochemical and clinical characteristics of methicillin-resistant S aureus are reviewed. The alarming increase of this organism in various types of infections demands the attention of all surgeons and emphasizes the importance of early surgical drainage and culture of pus in all cases of infection. (J Hand Surg 2000; 25A:173-175.

Abscess↗
PubMed1999

Immunolocalization of cyclooxygenase-2 in the macula densa of human elderly.

To gain insight into the role of prostanoids in human kidney function, we examined the distribution of cyclooxygenase (COX) 1 and COX-2 by immunofluorescence and immunohistochemistry in human kidneys from adults of various age groups. COX-1 was detected in the collecting ducts, thin loops of Henle and portions of the renal vasculature. COX-2 was detected in the renal vasculature, medullary interstitial cells, and the macula densa. In addition, COX-2 immunoreactivity was noted in afferent arteries and the macula densa of the renal cortex and was more evident in the kidneys of older adults.

Adolescent↗
PubMed1999

Lymphoproliferative disorders after organ transplantation in children.

BACKGROUND: After organ transplant, patients are at risk of posttransplant lymphoproliferative disorders (PTLD). The purpose of this study was to analyze 26 pediatric cases of PTLD observed at our institution between 1988 and 1996, and to evaluate the validity of the Society for Hematopathology Workshop (SHPW) 1997 classification in our patient population. METHODS: Charts were reviewed for analysis of incidence, clinical course, and outcome. Tissue samples were classified by a pathologist according to SHPW recommendations. RESULTS: By morphology, 20 were monomorphic, 5 polymorphic, and 1 hyperplastic. Assessment of lineage by morphology, molecular studies, and immunophenotyping did not correlate in six cases. By immunophenotyping, 12 were B cell, 4 T cell, 8 mixed B/T cells, and 2 undetermined. The 20 patients evaluable for treatment efficacy were treated with various therapeutic combinations, including immunosuppressive drug reduction, acyclovir/ganciclovir, interferon-alpha, immunoglobulins, surgery, and local irradiation. No patient received systemic chemotherapy. Thirteen patients achieved complete remission and 3, partial; 1 died 5 days after starting therapy, and 3 of progressive disease. Adverse prognostic factors included low platelet or neutrophil counts; stage III-IV and SHPW morphology were marginally significant. CONCLUSIONS: The majority of patients eligible for treatment can be cured with immunosuppressive drug reduction and antiviral drugs, along with surgery and irradiation when indicated. Systemic chemotherapy or innovative approaches may have a role in unresponsive cases. Morphologic SHPW grouping is feasible and seems to have clinical relevance. However, correlation with clonality and immunophenotyping is not always possible, necessitating modifications including segregation of descriptive morphology from clonality and cell origin.

Adolescent↗
PubMed1999

Trichinella spp.: differential expression of two genes in the muscle larva of encapsulating and nonencapsulating species.

Kuratli, S., Lindh, J. G., Gottstein, B., Smith, D. F., and Connolly, B. 1999. Trichinella spp.: Differential expression of two genes in the muscle larva of encapsulating and nonencapsulating species. Experimental Parasitology 93, 153-159. The expression of the two genes tsmyd-1 and tsJ5 was studied in the muscle stage larva of three different species of Trichinella. T. spiralis and T. britovi are both encapsulating species, while T. pseudospiralis is a nonencapsulating species. Expression of tsJ5 is developmentally regulated in T. spiralis and has been shown in this study to be down-regulated in the T. pseudospiralis muscle larva compared with the other two species. Immunoblot analysis has also revealed that the relative abundance of the protein product of this gene, TSJ5, is lower in T. pseudospiralis muscle larvae. It has previously been shown that expression of tsmyd-1 is not developmentally regulated in T. spiralis (Connolly et al. 1996). In contrast, expression of this gene is slightly increased in the muscle larvae of T. pseudospiralis. Southern analysis of genomic DNA from the three Trichinella species shows that both genes are highly conserved.

Animals↗