CA15-3, CASA,MSA, and TPS as diagnostic serum markers in breast cancer

Summary This is the first comparison of the three mucin based tests CA15-3, CASA, and MSA, and the cytokeratin-related TPS assay in breast cancer. The mucin markers were superior to TPS in receiver-operator analysis, though no marker was of use in the diagnosis of malignancy due to low sensitivity. Using cutpoints that gave 95% specificity in benign disease (n = 83), corresponding sensitivities in pre-treatment breast cancer (n = 123: 13in situ, 54 stage I, 45 stage II, 4 stage III, 7 stage IV) were 17% (CA15-3), 16% (CASA), 13% (MSA), and 8% (TPS), with a strong relationship between marker levels and disease stage. These assays did not always detect the same patients, and the use of CA15-3 combined with CASA gave the highest sensitivity (23%), though this was not significantly better than the use of CA15-3 alone. Despite detecting similar antigens, these assays can show markedly different responses in some patients, indicating that one mucin-based test cannot be sub-stituted for another.     

Dilation and evacuation during the second trimester of pregnancy in a woman with primary pulmonary hypertension. A case report

A woman with primary pulmonary hypertension was managed with second-trimester dilation and evacuation for pregnancy termination. This procedure can be of value in this clinical setting.     

Effect of telephone follow-up on the physical well-being dimension of quality of life in patients with cancer

OBJECTIVE: To evaluate the effect of telephone follow-up on the physical well-being dimension of health-related quality of life in patients with cancer. DESIGN: Randomized, controlled trial. SETTING: Public teaching hospital. PATIENTS: One hundred fifty patients with cancer who were discharged to home from the hospital. INTERVENTION: Patients received a telephone follow-up call 48-72 hours after discharge. Information was solicited regarding drug-related (and other) problems. Problems were addressed, and advice and support were given. MEASUREMENTS AND MAIN RESULTS: Analysis of variance revealed no differences in the physical well-being dimension of health-related quality of life between patients who received telephone follow-up and a control group who did not. Sixty-eight percent of the follow-up group and 40% of the control group (p = 0.007) reported having had at least one contact with a health professional. CONCLUSION: One possible explanation for the lack of effect of the intervention is that high-risk patients in the control group received a similar intervention from other health care professionals. We suggest that telephone follow-up be coordinated among health professionals.     

Nonorthologous replacement of lysyl-tRNA synthetase prevents addition of lysine analogues to the genetic code

Insertion of lysine during protein synthesis depends on the enzyme lysyl-tRNA synthetase (LysRS), which exists in two unrelated forms, LysRS1 and LysRS2. LysRS1 has been found in most archaea and some bacteria, and LysRS2 has been found in eukarya, most bacteria, and a few archaea, but the two proteins are almost never found together in a single organism. Comparison of structures of LysRS1 and LysRS2 complexed with lysine suggested significant differences in their potential to bind lysine analogues with backbone replacements. One such naturally occurring compound, the metabolic intermediate S-(2-aminoethyl)-L-cysteine, is a bactericidal agent incorporated during protein synthesis via LysRS2. In vitro tests showed that S-(2-aminoethyl)-L-cysteine is a poor substrate for LysRS1, and that it inhibits LysRS1 200-fold less effectively than it inhibits LysRS2. In vivo inhibition by S-(2-aminoethyl)-L-cysteine was investigated by replacing the endogenous LysRS2 of Bacillus subtilis with LysRS1 from the Lyme disease pathogen Borrelia burgdorferi. B. subtilis strains producing LysRS1 alone were relatively insensitive to growth inhibition by S-(2-aminoethyl)-L-cysteine, whereas a WT strain or merodiploid strains producing both LysRS1 and LysRS2 showed significant growth inhibition under the same conditions. These growth effects arising from differences in amino acid recognition could contribute to the distribution of LysRS1 and LysRS2 in different organisms. More broadly, these data demonstrate how diversity of the aminoacyl-tRNA synthetases prevents infiltration of the genetic code by noncanonical amino acids, thereby providing a natural reservoir of potential antibiotic resistance.     

MRI and neuropsychological correlates of carbon monoxide exposure: a case report

A 45-year-old woman experienced long-term, chronic exposure to carbon monoxide in the restaurant kitchen where she was employed as a cook. After returning to the restaurant after 5 days off work, she noticed that her symptoms returned immediately; she then aired out the room and called the gas company. Approximately 6 hr after a leak was detected, the patient went to the hospital, where her carboxyhemoglobin was found to be within normal limits and results of a neurologic examination were described as normal. Based on her symptoms, the patient believed she had been exposed to CO for at least 1 year before the leak was discovered. Initially, she experienced flu-like symptoms, which eventually resolved. At the time of her first neuropsychological evaluation (17 months after the exposure was identified), her persisting complaints included difficulties in reading, writing, speaking and word retrieval. The test results were consistent with secondary frontal lobe dysfunction associated with subcortical disorders such as those seen after CO exposure. Results of a subsequent neuropsychological examination (29 months postexposure) showed slight improvement in performance, but her performance was still consistent with mild frontal/subcortical dysfunction. Although the initial screening of a brain magnetic resonance image (MRI) performed 15 months after the exposure was interpreted as being within normal limits, two subsequent blind reviews of the same scans identified multiple bilateral lesions in the basal ganglia, which were consistent with chronic CO exposure. We present this case as an example of the utility of MRI and neuropsychological examinations in detecting central nervous system dysfunction secondary to CO exposure.     

Intracellular factor XIII crosslinks platelet cytoskeletal elements upon platelet activation

The platelet cytoplasm contains approximately half of the factor XIII (FXIII) transglutaminase content circulating in blood, yet the function of cytoplasmic FXIII is poorly understood. This study investigated functions of platelet FXIII in internal platelet processes by studying the interactions of FXIII with platelet cytoskeletal proteins. FXIII was present in cytoskeletal fractions of platelet lysate separated by centrifugation. When cytoskeletal fractions were immobilized on nitrocellulose membranes, thrombin-activated rFXIII (rFXIIIa*) or calcium ion-treated rFXIII (rFXIIIa degree) bound to some of these proteins, whereas untreated rFXIII did not. Utilizing fluorescence microscopy, an actin polymerization-dependent transient translocation of FXIII from a diffuse homogeneous distribution throughout the cytoplasm to the platelet periphery was observed upon platelet activation, suggesting an association with cytoskeletal proteins. Transglutaminase activity increased in cytoskeletal fractions of activated versus non-activated platelets. Immunoblotting analysis of platelet cytoskeletal fractions identified filamin and vinculin as being crosslinked upon platelet activation.     

Chronic radiographic lung changes in children with vertically transmitted HIV-1 infection

OBJECTIVE: We prospectively studied children with and without maternally transmitted HIV-1 infection born to mothers infected with HIV-1 to determine the incidence of chronic radiographic lung changes (CRC) and to correlate these changes with clinical assessments. SUBJECTS AND METHODS: Between 1990 and 1997, we scored 3050 chest radiographs using a standardized form. Group I children (n = 201) were HIV-1-infected at enrollment. Group II children (n = 512) were enrolled prenatally or before 28 days postpartum and subsequently subdivided into group IIa (n = 86), children identified as HIV-1-infected; and group IIb (n = 426), those who were HIV-1-uninfected. CRC were defined as parenchymal consolidations or nodular disease lasting 3 months or more or increased bronchovascular markings or reticular densities lasting 6 months or more. Morbidity was assessed by CD4 counts, viral load, the presence of low oxygen saturation, wheezing, tachypnea, crackles, and clubbing. RESULTS: The cumulative incidence of chronic radiographic lung changes in HIV-1-infected children was 32.8% by 4 years old, with increased bronchovascular markings or reticular densities being most common. Chronic changes were associated with lower CD4 cell counts and higher viral loads. Resolution of these chronic changes was associated with decreasing CD4 cell counts but not with lower rates of clinical findings, viral load, or difference in survival. CONCLUSION: With increased survival, CRC are becoming more common. The resolution of these changes may indicate immunologic deterioration rather than clinical improvement.     

High mobility group proteins 1 and 2 recognize chromium-damaged DNA

Chromium (Cr) is a human carcinogen and a potent DNA damaging agent. Incubation of DNA with CrCl3 resulted in dose-dependent binding of Cr to DNA and, at concentrations >20 microM, altered the electrophoretic mobility of a 100 bp oligonucleotide. We also demonstrate that high mobility group (HMG) proteins 1 and 2 bind Cr-damaged DNA (Cr-DNA). Protein binding was lesion density-dependent, with maximal binding to DNA treated with 100 microM CrCl3. HMG2 binds to Cr-DNA with a calculated Kd of approximately 10(-9) M. These proteins also bound DNA obtained from chromate-treated cells. These results suggest that the covalent attachment of Cr to DNA induces alterations in DNA structure which are recognized by HMG1 and HMG2. Therefore, these proteins may function as Cr-damaged DNA recognition proteins in vivo and as a consequence of binding, may play a role in directing the cellular response to Cr-DNA adduct formation.      

Monoclonal antibodies reacting with the MUC2 mucin core protein.

This study sought to produce monoclonal antibodies (MAbs) which reacted with the MUC2 core protein. Two MAbs [3A2 (IgG1) and 4F1 (IgM)] were produced by immunising female BALB/c mice with gel-formed mucin from the LS174T colon cancer cell line followed by a KLH conjugate of a 29 amino acid synthetic peptide whose sequence was derived from the variable number of tandem repeats (VNTR) region of a MUC2 cDNA clone. The MAbs reacted with synthetic MUC2 VNTR peptides but not synthetic MUC1 or MUC3 VNTR peptides, and showed specific reactivity in Western blotting with a high molecular weight protein produced by the LS174T colon carcinoma cell line. The use of shorter peptides indicated that the minimum peptide epitopes for these MAbs were different. Mab 3A2 reacted with amino acids 5-19 of the MUC2 VNTR by inhibition ELISA but not by direct ELISA, while 4F1 reacted with this peptide in both assays. Furthermore, 4F1 reacted in direct ELISA when a larger (29 amino acid) MUC2-derived peptide was coated onto the assay plate by incubating in carbonate buffer or by drying the peptide onto the assay plate, while 3A2 only reacted when this peptide was coated in carbonate buffer. The different specificity of the MAbs was also illustrated by the reactivity of 4F1 but not 3A2 with partially deglycosylated cystic fibrosis mucin. Immunohistochemical analysis with these MAbs revealed a strong reactivity with lung, gastric and colon tumours relative to normal tissue, with some breast and ovarian tumours also reacting. Both MAbs stained some normal goblet cells in the perinuclear region but not the mucin droplet or secreted mucin, indicating a reaction with immature (poorly glycosylated) mucin in the endoplasmic reticulum and/or golgi, but not with mature (fully glycosylated) mucin. In contrast, tumours showed strong diffuse cytoplasmic staining. 4F1 also showed weak apical cytoplasmic staining in some goblet cells and stained some tumours which showed no reactivity with 3A2. These antibodies should prove useful in the study of MUC2 structure and function, and in the diagnosis of some tumours.