Clinical efficacy of seasonal influenza vaccination: characteristics of two outbreaks of influenza A(H1N1) in immunocompromised patients.

BACKGROUND: Influenza A(H1N1) causes serious complications in immunocompromised patients. The efficacy of seasonal vaccination in these patients has been questioned. AIM: To describe two outbreaks of influenza A(H1N1) in immunocompromised patients. METHODS: Two outbreaks of influenza A(H1N1) occurred in our institution: on the kidney transplant ward in 2014 including patients early after kidney or simultaneous pancreas-kidney transplantation, and on the oncology ward in 2016 including patients receiving chemotherapy for malignant tumours. Factors leading to these outbreaks and the clinical efficacy of seasonal influenza vaccination were analysed. FINDINGS: Altogether 86 patients were exposed to influenza A(H1N1) during the outbreaks, among whom the seasonal influenza vaccination status was unknown in 10. Only three out of 38 vaccinated patients were infected with influenza A(H1N1), compared with 20 out of 38 unvaccinated patients (P = 0.02). The death of one out of 38 vaccinated patients was associated with influenza, compared with seven out of 38 unvaccinated patients (P = 0.06). Shared factors behind the two outbreaks included outdated facilities not designed for the treatment of immunosuppressed patients. Vaccination coverage among patients was low, between 40% and 70% despite vaccination being offered to all patients free of charge. Vaccination coverage of healthcare workers on the transplant ward was low (46%), but, despite high coverage on the oncology ward (92%), the outbreak occurred. CONCLUSION: Seasonal influenza vaccination was clinically effective with both a reduced risk of influenza infection and a trend towards reduced mortality in these immunocompromised patients. Several possible causes were identified behind these two outbreaks, requiring continuous awareness in healthcare professionals to prevent further outbreaks.

Dose-densified chemoimmunotherapy followed by systemic central nervous system prophylaxis for younger high-risk diffuse large B-cell/follicular grade 3 lymphoma patients: results of a phase II Nordic Lymphoma Group study.

BACKGROUND: Many patients with aggressive B-cell lymphomas and high clinical risk score still die of lymphoma after conventional R-CHOP chemoimmunotherapy. We hypothesized that intensified chemoimmunotherapy including systemic central nervous system (CNS) prophylaxis improves outcome and reduces the incidence of CNS-related events. PATIENTS AND METHODS: Inclusion criteria were age 18-65 years, primary diffuse large B-cell lymphoma or grade III follicular lymphoma without clinical signs of CNS disease and negative cerebrospinal fluid cytology, age-adjusted International Prognostic Index 2-3 and WHO performance score 0-3. Treatment consisted of six courses of R-CHOEP-14 followed by a course of high-dose cytarabine and a course of high-dose methotrexate. Primary end point was failure-free survival (FFS) at 3 years. RESULTS: A total of 156 eligible patients with a median age of 54 years (range 20-64) were included. Three toxic deaths were observed. Three-year overall survival (OS) and FFS rates (median observation time 52 months for survivors) were 81% and 65%, respectively. Seven patients experienced CNS relapse, all within 6 months. CONCLUSIONS: The results are promising with favorable 3-year OS and FFS rates, a low toxic death rate and a lower than expected number of CNS events. CNS progression might be further reduced by earlier CNS prophylaxis. CinicalTrials.gov. identifier NCT01502982.

Complement activation in circulation and central nervous system after rituximab (anti-CD20) treatment of B-cell lymphoma.

Rituximab (IDEC-C2B8, Mabthera, Rituxan), a chimeric monoclonal antibody against the B-cell specific CD20-antigen, has been demonstrated to be effective in the treatment of non-Hodgkin's B-cell lymphoma (B-NHL). Previous in vitro studies have shown that direct complement-dependent cytotoxicity (CDC), ADCC and apoptosis are important in the rituximab-induced killing of lymphoma cells. It is, however, unknown whether rituximab penetrates the blood-brain barrier. Therefore, we studied rituximab levels and complement (C) activation in blood and cerebrospinal fluid (CSF) following intravenous rituximab therapy in a patient with relapsing non-Hodgkin's lymphoma with central nervous system (CNS) involvement. Longitudinal samples from blood and CSF were taken at 13 time-points during the treatment period. The results show that the C cascade becomes activated in blood during the first mAb infusion (C3a-desArg concentration rose from 55 to 138 microg/ml during the first 2 hours). After the first infusion the proportions of lymphocytes positive for the CD19- and CD20-antigens in the peripheral blood were reduced from 41% and 35%, respectively, to a level of 2% (for both). In CSF the rituximab concentration increased after successive infusions, but remained below 0.55 microg/ml (compared to a Cmax of 400 microg/ml in peripheral blood). Although a minor and delayed C activation response was seen in the CSF the treatment did not clear CD20-positive cells away from the CNS. Thus, it appears that an intact blood-brain barrier restricts the entry of rituximab into the CNS. Possible options to circumvent this would be dose escalation or intrathecal rituximab treatment.

Synchrotron radiation circular dichroism spectroscopy of proteins: secondary structure, fold recognition and structural genomics.

Recent developments in instrumentation and bioinformatics show that the technique of synchrotron radiation circular dichroism spectroscopy can provide novel information on protein secondary structures and folding motifs, and has the potential to play an important role in structural genomics studies, both as a means of target selection and as a high-throughput, low-sample-requiring screening method. This is possible because of the additional information content in the low-vacuum ultraviolet wavelength data obtainable with intense synchrotron radiation light sources, compared with that present in spectra from conventional lab-based circular dichroism instruments.

Synchrotron radiation circular dichroism spectroscopy: vacuum ultraviolet irradiation does not damage protein integrity.

Synchrotron radiation circular dichroism (SRCD) spectroscopy is an emerging technique for sensitive determination of protein secondary structures and for monitoring of conformational changes. An important issue for its adoption as a useful technique is whether the high-intensity low-wavelength vacuum ultraviolet radiation in the SRCD chemically damages proteins. In this paper, using horse myoglobin as a test sample, it is shown that extensive irradiation in the SRCD does not produce any change in the chemical nature of the protein as detected by either SDS gel electrophoresis or mass spectrometry. In addition, no changes in the protein secondary structure are detectable from the SRCD spectra after extensive exposure to the SRCD beam.

Screening of a library of phage-displayed peptides identifies human bcl-2 as a taxol-binding protein.

A random library of phage displayed peptides was screened for binding to a biotinylated derivative of paclitaxel (Taxol). Affinity-selected peptides were analyzed for similarity to human proteins. There was no significant similarity between the paclitaxel-selected peptides and tubulin. However, a subset of the peptides was identified that exhibits significant similarity to a non-conserved region of the anti-apoptotic human protein Bcl-2: ELISA assays confirmed binding of paclitaxel to Bcl-2, and circular dichroism spectroscopy demonstrated that a substantial conformational change accompanies this binding. In vivo, treatment with paclitaxel has been shown to lead to Bcl-2 inactivation with concomitant phosphorylation of residues in a disordered, regulatory loop region of the protein. Similarity between paclitaxel-selected peptides and this loop region implicate these residues in drug binding, and suggest that the apoptotic action of paclitaxel may involve the binding of paclitaxel to Bcl-2. These results demonstrate that peptides displayed on the surface of bacteriophage particles can mimic the ligand-binding properties of disordered regions of proteins.

Urinary 5-hydroxyindoleacetic acid (5-HIAA) excretion during multiple-day high-dose chemotherapy.

Highly emetogenic drugs such as cisplatin induce an increase in the urinary 5-hydroxyindoleacetic acid (5-HIAA) level, the main metabolite of serotonin (5-HT), within the first 24 h following a single infusion, thus providing a possible cause for acute emesis and an explanation for the action of 5-HT3 antagonists. No further excretion peaks have been observed, suggesting that additional or serotonin-independent mechanisms cause delayed emesis. Our aim was to study the mechanisms behind emesis seen during a highly emetogenic chemotherapy regimen given as a continuous infusion over several days. Seven women treated with a 4-day high-dose chemotherapy (HDCT) regimen for breast cancer entered the study. Pooled urine samples were collected prior to and during chemotherapy for determining 5-HIAA excretion. An excretion peak in the urinary 5-HIAA level was observed within the first 24 h with no further peaks thereafter. Thus, the mechanisms behind the emesis experienced during this highly emetogenic multiple-day chemotherapy regimen from days 2-3 onwards would appear to be at least partially serotonin independent and would not be expected to be completely relieved by 5-HT3 antagonists alone.

A molecular model for human Big-Endothelin-1 (Big ET-1).

A molecular model has been developed for human Big Endothelin-1, which is the immediate precursor to the potent vasoconstrictor polypeptide endothelin-1 and the target of the highly specific endothelin converting enzyme. This model is produced by a threading algorithm protocol and is consistent with all the currently available structural and biochemical data for this molecule.

National patterns of care for pancreatic cancer. Results of a survey by the Commission on Cancer.

BACKGROUND: The Commission on Cancer of the American College of Surgeons conducted a large, national survey to assess methods of diagnosis, American Joint Commission on Cancer staging, treatment, and outcome of patients with adenocarcinoma of the pancreas. STUDY DESIGN: The survey questionnaire contained 160 questions and covered two study periods, 1983 to 1985 and 1990, for time-trend analysis. Nine hundred seventy-eight institutions throughout the United States voluntarily participated, contributing 8917 case reports for 1983 to 1985 and 8025 reports for 1990, resulting in a total of 16,942 patient reports. Most, but not all, of the participating hospitals maintain approval status with the Commission on Cancer of the American College of Surgeons. RESULTS: The ratio of male-to-female cases was 1:1. Patient characteristics including age, ethnicity, neighborhood income, type of insurance coverage, and hospital characteristics--including annual caseload and type of facility (e.g., teaching, community)--appeared to influence surgical multimodality treatment patterns. The most common presenting symptom was abdominal pain. The reported history of smoking for these patients with pancreatic cancer was higher than U.S. population averages. The frequency of using abdominal computed tomography scans, endoscopic retrograde cholangiopancreatography, carcinoembryonic antigen, and CA 19-9 during patient evaluation all increased. Time trends toward lower operative mortality and more extirpative surgery were reported, as was a slightly higher survival for those patients who were resected surgically. CONCLUSIONS: Pancreatic cancer continues to be a disease of older patients. There were slight improvements in operative mortality. For a highly selective category of patients, cancer-directed surgery offers a chance for cure with excellent operative mortality and acceptable complication rates, especially when performed in institutions that have a 20 or greater case per year experience.

Initial 300 consecutive stereotactic core-needle breast biopsies by a surgical group.

BACKGROUND: Stereotactic localization and breast biopsy by fine needle and 14-gauge core needle is a new technique for diagnosing nonpalpable breast lesions. The procedure employs a device that affords extremely accurate localization and sampling of nonpalpable breast abnormalities. METHODS: We are a 5-man surgical group reporting on the experience of our initial 300 consecutive stereotactic core-needle biopsies (SCNB). RESULTS: The procedures, conducted over a 13-month period, revealed 37 cancers, for a malignancy rate of 12%. Seven percent were infiltrating ductal carcinoma and 4% ductal carcinoma in situ. There were 2 cases of adenocarcinoma, and 1 case of mucinous carcinoma. Benign microscopic diagnoses included 193 categorized as "fibrocystic change," 34 "fibroadenomas," 19 "benign breast tissue," and 5 lesions that were suspected of being malignant but were proven to be benign. There were 12 "others." CONCLUSION: We conclude that SCNB is an essentially painless, short outpatient procedure with a reduced cost compared to open biopsy. It can be easily mastered by surgeons. Results are comparable to controlled series in the literature, and rates of malignant diagnosis are similar to our group's experience in previous years.

The crystal structure of human endothelin.

The three-dimensional structure of the vasoactive polypeptide endothelin, the most potent vasoconstrictor yet identified, has been determined by X-ray crystallography to 2.18 A resolution. This intermediate-sized structure was solved by molecular replacement techniques using a fragment of an NMR-derived model for initial phasing of the data. However, comparisons of the final X-ray structure with the many diverse models derived from NMR data indicate some important differences, especially in the carboxy-terminal region of the molecule: the entire carboxy terminal tail (residues 16-21) is helical in the crystal structure, but not in any of the NMR structures. This may be a functionally significant difference as this region is crucial for receptor binding and vasoactivity.

Preliminary crystallization and X-ray analysis of orthorhombic human endothelin.

Human endothelin (ET-1) is a highly potent, ubiquitous, endogenous 21 amino acid residue polypeptide, which acts as a vaso- and bronchoconstrictor. Crystals of the active, uncomplexed form of ET-1 have been grown from aqueous solutions. These crystals, which are long hexagonal prisms, diffract to 2.98 A and are apparently of the space group P222(1) with cell dimensions a = 33.5 A, b = 57.9 A, c = 59.6 A. The six molecules in the asymmetric unit are related by non-crystallographic symmetry operations, which result in a pseudo 6(1) appearance to the data.

Co-crystals of gramicidin A and phospholipid. A system for studying the structure of a transmembrane channel.

Single crystals of a complex of gramicidin A, a transmembrane channel-forming polypeptide, and dipalmitoyl phosphatidylcholine, a phospholipid, have been prepared and characterized by X-ray diffraction. They belong to space group P222(1), with unit cell dimensions a = 26.8 A, b = 27.5 A, c = 32.8 A. The asymmetric unit appears to be a complex of one gramicidin monomer and two phospholipid molecules. The unit cell dimensions, space group, and chemical composition are compatible with lipids packing in a bilayer-like motif, and an end-to-end association of gramicidin monomers to form a functional dimeric unit. The crystals diffract to 2 A and are suitable for structural studies by single-crystal X-ray analysis. This represents the first example of a well-ordered crystalline channel complexed with lipids, and solution of its structure may give insight into mechanisms of ion transport across membranes.