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C Carlson

Publications and source records attributed to C Carlson.

At least 37 records · Page 2Linked to original sources
PubMed1996

Strategies for manipulating apoptosis for cancer therapy with tumor necrosis factor and lymphotoxin.

Tumor necrosis factor (TNF) and lymphotoxin (LT), initially described as tumoricidal proteins, may be useful as adjuncts in cancer therapy. Treatment with TNF or LT was found to protect cells and animals against damage mediated by radiation or cytotoxic anticancer drugs. By contrast, tumor cells treated with TNF or LT were sensitized to these insults. We present a model in which TNF or LT induces both the synthesis of "protective" proteins such as manganous superoxide dismutase (MnSOD) and the activation of "killing" proteins, such as proteases, depending on the level of the inducing signal. Although the p55-TNF/LT receptor is structurally related to the Fas receptor, they can each signal apoptosis by distinct pathways. Furthermore, activation of both receptors acts synergistically in stimulating apoptosis.

Animals↗
PubMed1996

Identifying DNA polymorphisms in human TCRA/D variable genes by direct sequencing of PCR products.

The T-cell receptor (TCR) is a highly variable molecule composed of two polypeptide chains that recognize antigenic peptides in the context of major histocompatibility complex (MHC) molecules. In this study, we describe a sequence-based search for germline polymorphisms in the variable (V) gene segments of the human TCRA/D locus. Thirty different V gene segments were amplified from six to eight unrelated individuals and sequenced from low melting point agarose. Twenty-seven polymorphisms were identified in 15 V gene segments. These polymorphisms are mainly single nucleotide substitutions, but an insertion/deletion polymorphism and a single dinucleotide repeat with variable length were also seen. Of the 15 sequence variations found in the coding regions, six are silent and nine encode amino acid changes. All of the amino acid changes are found at non-conserved residues, frequently in the hypervariable regions, where they may influence MHC and/or peptide recognition. Therefore, it is possible that germline variations in TCR genes could influence an individual's immune response, and may also contribute to susceptibility to diseases such as autoimmunity.

Amino Acid Sequence↗
PubMed1996

The influence of cutaneous tissue afferents on masticatory pain-pressure thresholds.

Pain-pressure thresholds are routinely used in orofacial pain research to record tenderness in masticatory muscles. This method is employed to stimulate deep tissue afferents, which are thought to be at least partially responsible for pain in temporomandibular disorders. Like other psychophysical measurements, however, this technique must stimulate cutaneous tissues before stimulating deeper tissues. This study examined 39 asymptomatic volunteers to quantify the effect of cutaneous sensory afferents on pain-pressure thresholds. In a randomized, double-blind fashion, pain-pressure thresholds were recorded at four facial sites before and after subjects received intradermal local anesthetic or a dry needle stick. Pain-pressure thresholds were significantly elevated after local anesthetic (P < .0001), suggesting that cutaneous tissues contribute significantly to the pain-pressure threshold. The authors discuss potentially important roles of cutaneous tissues in the assessment of deeper tissues and offer two theories of how the skin may be an important link in the assessment of temporomandibular disorders.

Administration, Cutaneous↗
PubMed1995

Identification, sequence, and transcriptional analysis of lef-3, a gene essential for Orgyia pseudotsugata baculovirus DNA replication.

Using a transient complementation assay for DNA replication of an origin-containing reporter plasmid, a 2.4-kb region (m.u. 48.3-50.1) of the Orgyia pseudotsugata multinucleocapsid nuclear polyhedrosis virus (OpMNPV) genome was identified that contains a gene essential for OpMNPV DNA replication. This region was sequenced and open reading frames were identified. Replication assays using subclones from this region identified a gene called late expression factor 3 (lef-3), as the essential replication gene. Transcriptional mapping using both Northern blot and S1 nuclease protection assays demonstrated that lef-3 was expressed as an early gene with a major transcript of 1.7 kb in length. OpMNPV lef-3 encodes a protein with a predicted molecular weight of 42.6 kDa (373 amino acids) and exhibits 41% amino acid sequence identity with its homolog in the genome of the Autographa californica MNPV. A pattern of amino acids similar to that found in single-stranded DNA binding proteins is present in the amino-terminus of both OpMNPV and AcMNPV LEF-3.

Amino Acid Sequence↗
PubMed1995

Velo-cardio-facial syndrome: frequency and extent of 22q11 deletions.

Velo-cardio-facial (VCFS) or Shprintzen syndrome is associated with deletions in a region of chromosome 22q11.2 also deleted in DiGeorge anomaly and some forms of congenital heart disease. Due to the variability of phenotype, the evaluation of the incidence of deletions has been hampered by uncertainty of diagnosis. In this study, 54 patients were diagnosed with VCFS by a single group of clinicians using homogeneous clinical criteria independent of the deletion status. Cell lines of these patients were established and the deletion status evaluated for three loci within the commonly deleted region at 22q11.2 using fluorescence in situ hybridization (FISH). In 81% of the patients all three loci were hemizygous. In one patient we observed a smaller interstitial deletion than that defined by the three loci. The phenotype of this patient was not different from that observed in patients with larger deletions.

Abnormalities, Multiple↗
PubMed1995

Peak height variations in automated sequencing of PCR products using Taq dye-terminator chemistry.

Direct sequencing of PCR products using Taq DNA polymerase with dye-labeled dideoxy chain terminators results in traces with uneven peaks. The peak height variations reflect the disproportionate rate of incorporation of deoxynucleotides vs. their analogs, a phenomenon that is highly dependent on the neighboring DNA sequence. Such peak height variations make it difficult to call bases correctly or to interpret whether or not a polymorphism is present. We have systematically examined pairs of sequence-tagged sites that vary at only one nucleotide to determine how a single base change will affect the peak heights of neighboring bases. We have found that the peak height of a particular base can often be predicted from the knowledge of just one or two nucleotides 5'- to the base in question. We have also observed several artifacts that occur consistently in the sequencing traces. These artifacts can be misinterpreted as polymorphisms or can obscure the real peak at that site. The empirically derived trends presented in this report can be utilized profitably when one is editing sequence data or examining them for polymorphisms and mutations.

Coloring Agents↗
PubMed1995

Molecular definition of the 22q11 deletions in velo-cardio-facial syndrome.

Velo-cardio-facial syndrome (VCFS) is a common genetic disorder among individuals with cleft palate and is associated with hemizygous deletions in human chromosome 22q11. Toward the molecular definition of the deletions, we constructed a physical map of 22q11 in the form of overlapping YACs. The physical map covers > 9 cM of genetic distance, estimated to span 5 Mb of DNA, and contains a total of 64 markers. Eleven highly polymorphic short tandem-repeat polymorphic (STRP) markers were placed on the physical map, and 10 of these were unambiguously ordered. The 11 polymorphic markers were used to type the DNA from a total of 61 VCFS patients and 49 unaffected relatives. Comparison of levels of heterozygosity of these markers in VCFS patients and their unaffected relatives revealed that four of these markers are commonly hemizygous among VCFS patients. To confirm these results and to define further the breakpoints in VCFS patients, 15 VCFS individuals and their unaffected parents were genotyped for the 11 STRP markers. Haplotypes generated from this study revealed that 82% of the patients have deletions that can be defined by the STRP markers. The results revealed that all patients who have a deletion share a common proximal breakpoint, while there are two distinct distal breakpoints. Markers D22S941 and D22S944 appear to be consistently hemizygous in patients with deletions. Both of these markers are located on a single nonchimeric YAC that is 400 kb long. The results also show that the parental origin of the deleted chromosome does not have any effect on the phenotypic manifestation.

Abnormalities, Multiple↗
PubMed1994

A targeted chain-termination mutation in the mouse Apc gene results in multiple intestinal tumors.

Germ-line mutations in the human adenomatous polyposis coli (APC) gene result in familial adenomatous polyposis, an autosomal dominant disorder characterized by the early onset of multiple adenomatous polyps in the large bowel with a high likelihood of developing colorectal carcinomas. To understand the role of APC in intestinal tumor formation, we have introduced a chain-termination mutation in the 15th exon of the mouse Apc gene and employed it to modify the endogenous gene by homologous recombination in embryonic stem cells. Mice which are heterozygous for the Apc gene modification progressively develop intestinal tumors in a manner that is similar to that observed in patients with familial adenomatous polyposis and in mice which carry a mutation called multiple intestinal neoplasia (Min). Our results indicate that the Apc gene modification is a critical event in the initiation of intestinal tumor formation and results in an autosomal dominant predisposition toward development of spontaneous colonic and intestinal tumors in mice.

Adenomatous Polyposis Coli↗
PubMed1994

Comparative analysis of human DNA variations by fluorescence-based sequencing of PCR products.

Automated, direct cycle sequencing of purified double-stranded PCR products using Taq polymerase and fluorescently labeled dideoxynucleotide terminators provides a robust and highly reproducible method for identifying DNA sequence variations in sequence-tagged sites. We describe a simple and sensitive strategy that reliably detects the presence of DNA variations when sequencing traces from several different individuals are compared. We also demonstrate the use of this strategy to estimate allele frequencies of single nucleotide substitutions in a population. Taken together, this approach provides an automated method for conducting rapid population studies of candidate gene regions that are in linkage or association with a specific disease and for comparative evolutionary analysis of selected regions of the human genome.

Alleles↗
PubMed1992

The effect of sodium cromoglycate eyedrops compared to the effect of terfenadine on acute symptoms of seasonal allergic conjunctivitis.

A multicentre, group comparative open study was carried out on 68 patients to compare the effects of 2% sodium cromoglycate eyedrops and an oral antihistamine, terfenadine, on acute symptoms of seasonal allergic conjunctivitis. The study was continued for one week after the onset of acute symptoms. Both medications were equally efficient in reducing symptoms during the first hour of observation. During the one-week follow-up both medications reduced symptoms to a low level, and both medications were equally effective for allergic symptoms, except that terfenadine was more effective in reducing the watering of eyes.

Acute Disease↗
PubMed1991

Problems affecting the liquid chromatographic quantitation of chlorhexidine digluconate in ophthalmic solutions.

A liquid chromatogrpahic (LC) assay was recommended by the Food and Drug Administration of the United States for the uptake and release study of chlorhexidine digluconate (CHDG) in ophthalmic solutions by contact lenses. The results from this and other reversed-phase LC assays of CHDG were inaccurate when the working standard and sample solution matrices were different. The error was caused by binding of the analyte onto the container surface and LC column packings. The loss of chlorhexidine due to binding was dependent upon, and very sensitive to, the counter ions in the sample solutions. Relative to water solutions of CHDG, solutions containing chloride, thiosulphate and edetate reduced the loss of the analyte, while solutions containing borate enhanced the loss. To assay CHDG reliably with reversed-phase LC, the media of the working standard and the sample solutions should be closely matched.

Chlorhexidine↗
PubMed1990

Group therapy with sexually abused boys: leadership, projective identification, and countertransference issues.

Group therapy is an essential component of the treatment of sexually abused children. Since the painful effects associated with the abuse are often dissociated or acted out, the group leaders learn of the affective experience of the abuse through the process of projective identification. The leaders must be aware of this process, set limits on the abusive acting out in the group, and help moderate, label, and empathize with the affect. It is through this difficult process that the children have a chance to reintegrate and work through their abuse experiences so they no longer feel compelled to act them out through repetitive abusive relationships. Specific leadership, countertransference, and projective identification issues in group therapy with sexually abused boys are discussed.

Adolescent↗
PubMed1990

Classification of pressure ulcers.

Several systems exist for classifying pressure ulcers, though none of them have been evaluated for interrater reliability. A new grading scale was compared with the commonly used Shea classification. This new scale was developed to provide a more complete description of pressure ulcer healing. The advantages of this scale include a classification of red areas as ulcers to help prevent further deterioration and classification of healed sores to note potential problems. The Yarkony-Kirk scale classifies a red area as a grade 1 ulcer, and involvement of the epidermis and dermis with no subcutaneous fat observed as a grade 2 ulcer. Grade 3 indicates exposed subcutaneous fat with no muscle observed. Exposed muscle without bone involvement is classified as a grade 4 ulcer, and grade 5 describes exposed bone with no joint space involvement. Grade 6 indicates joint space involvement. There is a classification of pressure sore healed to indicate a healed pressure ulcer. Interrater reliability was assessed by two nurses. In spite of an increased number of categories for the Yarkony-Kirk scale, there was no decline in reliability. Reliability was excellent with an interrater correlation of 0.90 for the Yarkony-Kirk scale and 0.86 for the Shea classification when measured for 72 patients. Eighty-five percent of the ratings for the Yarkony-Kirk scale were identical, whereas only 68% were identical for the Shea classification. Three percent of the ratings for the Shea classification were greater than +/- 1 category; 6% of the ratings for the Yarkony-Kirk scale were greater than +/- 1 category. This scale appears to possess good reliability and to describe pressure ulcers more completely. This scale may also be used to teach prevention activities as well as ulcer classification.

Humans↗
PubMed1990

Double-blind group comparative study of 2% nedocromil sodium eye drops with placebo eye drops in the treatment of seasonal allergic conjunctivitis.

A multicenter double-blind group comparative study was carried out in 126 patients, 64 of whom received 2% nedocromil sodium eye drops, and 62 placebo eyedrops twice each day for the treatment of seasonal allergic conjunctivitis to birch pollen. The patients were evaluated at 2 week intervals for clinical signs of conjunctivitis and kept daily diary records of eye symptoms (0-4 severity scales) and concomitant therapy. Diary trends favored active treatment, and reached significance for excessive lacrimation (P less than .05) during peak pollen challenge. Clinic assessments showed the same directional trend and final opinions of treatment efficacy were significantly in favor of nedocromil sodium (P = .003, patients; P = .006, clinicians). In addition, the placebo group used significantly more topical (P less than .05) and oral (P less than .01) concomitant antihistamine therapy. Nedocromil sodium and placebo treatments were equally acceptable and well tolerated. The results show that 2% nedocromil sodium used topically twice each day is an effective therapy for seasonal allergic conjunctivitis.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1990

Antibiotic prophylaxis for cesarean delivery: is an extended-spectrum agent necessary?

The purpose of this investigation was to determine whether an extended-spectrum antibiotic with a long duration of action was more effective for prophylaxis for cesarean delivery than a limited-spectrum agent with a shorter duration of action. Patients were eligible for the study if they were in labor or had ruptured membranes at the time of surgery. In a randomized, double-blind manner, 377 women were assigned to receive 2 g of cefazolin (192) or 2 g of cefotetan (185) intravenously immediately after the infant's umbilical cord was clamped. There were no significant differences between groups with respect to the frequency of febrile morbidity (22.4 versus 21.6%), the mean fever index (15.8 versus 14.9 degree-hours), the frequency of endometritis (19.3 versus 21.1%), or the mean duration of postoperative hospitalization (3.8 versus 3.9 days). Among patients who became infected despite prophylaxis, enterococcus was isolated with disproportionate frequency. This organism was responsible for 89% of the postoperative urinary tract infections and all three cases of bacteremia. It was also the second most common isolate in women with endometritis. A single dose of cefazolin is comparable in effectiveness to cefotetan. In view of the cost difference between the two antibiotics, there is no justification for use of the more expensive, extended-spectrum agent.

Cefazolin↗
PubMed1989

A computer graphics study of multistranded DNA models.

A range of related nucleic acid models has been built using the computer graphics system at EMBL (Heidelberg). The relationship between these models is considered in terms of a simple "core" structure. One of these models is a four-strand structure in which two duplexes of the Watson-Crick kind are specifically related by a twofold rotation axis and which has already been discussed in some detail. The models fall into two principal classes. In one, each sugar phosphate chain is attached to every layer of bases in the "core" structure; in the other, each chain is attached to alternate layers of bases. Several of the models discussed have specificity both of complementarity and of identity.

Computer Graphics↗