Quantitative assessment of haemolysis secondary to modern infusion pumps.

BACKGROUND: Although most studies have shown that little haemolysis is induced by infusion pumps, there are some notable exceptions. Only limited data are available on the actual infusion pumps that are most used in hospitals in Quebec and elsewhere, namely, the Infusomat® Space (peristaltic), Plum A+™ (piston) and Colleague® CXE (shuttle) pumps. METHODS: Haemolysis and potassium levels were compared before and after the use of the three different infusion pumps. Using 135 units of packed red blood cells (RBCs) aged from 10 to 28 days, 27 measurements were taken for each pump at various flow rates (30, 60, 150, 300 and 450 ml/h) and were compared with measurements taken before using the pumps. The range of flow rates was chosen to cover those of paediatric and adult transfusions. RESULTS: The shuttle- and piston-type pumps resulted in low haemolysis levels. The peristaltic-type pump produced significantly more haemolysis, which worsened at low flow rates, but the absolute value of haemolysis remained within the range recommended by the regulatory agencies in North America and Europe. Approximately two-thirds of the haemolysis produced by the peristaltic-type pump seemed to be secondary to the use of an antisiphon valve (ASV) on the transfusion line recommended by the manufacturer. Potassium levels did not increase with the use of the pumps. CONCLUSION: Modern infusion pumps widely used in hospitals in Quebec and elsewhere produce non-threatening levels of haemolysis during the transfusion of packed RBCs aged from 10 to 28 days. ASVs appear to induce additional haemolysis, and we do not recommend using them for blood transfusion.

Synchronous metastatic skull base chordoma to the breast: case report and literature review.

CLINICAL SCENARIO: During routine staging work-up for a left breast mass, a 68-year-old woman complained of dysphagia and dysphonia. During further investigations, a left-sided lesion at the foramen magnum was observed on brain imaging. Both lesions were biopsied and showed a classical chordoma. MANAGEMENT: The skull-base lesion and the breast lesion were surgically resected, and adjuvant radiotherapy was given. SUMMARY: Chordoma is a rare primary central nervous system tumour that seldom metastasizes. The lung is the most common site of metastasis. Synchronous breast metastasis from a skull-base chordoma is very rare, and a safe management option includes a maximum resection followed by adjuvant radiotherapy.

A Canadian national expert consensus on neoadjuvant therapy for breast cancer: linking practice to evidence and beyond.

BACKGROUND: Use of the neoadjuvant approach to treat breast cancer patients has increased since the early 2000s, but the overall pathway of care for such patients can be highly variable. The aim of our project was to establish a multidisciplinary consensus among clinicians with expertise in neoadjuvant therapy (nat) for breast cancer and to determine if that consensus reflects published methods used in randomized controlled trials (rcts) in this area. METHODS: A modified Delphi protocol, which used iterative surveys administered to 85 experts across Canada, was established to obtain expert consensus concerning all aspects of the care pathway for patients undergoing nat for breast cancer. All rcts published between January 1, 1967, and December 1, 2012, were systematically reviewed. Data extracted from the rcts were analyzed to determine if the methods used matched the expert consensus for specific areas of nat management. A scoring system determined the strength of the agreement between the literature and the expert consensus. RESULTS: Consensus was achieved for all areas of the pathway of care for patients undergoing nat for breast cancer, with the exception of the role of magnetic resonance imaging in the pre-treatment or preoperative setting. The levels of agreement between the consensus statements and the published rcts varied, primarily because specific aspects of the pathway of care were not well described in the reviewed literature. CONCLUSIONS: A true consensus of expert opinion concerning the pathway of care appropriate for patients receiving nat for breast cancer has been achieved. A review of the literature illuminated gaps in the evidence about some elements of nat management. Where evidence is available, agreement with expert opinion is strong overall. Our study is unique in its approach to establishing consensus among medical experts in this field and has established a pathway of care that can be applied in practice for patients receiving nat.

Concurrent chemoradiotherapy for locally advanced breast cancer-time for a new paradigm?

BACKGROUND: In cases of locally advanced breast cancer (labc), preoperative ("neoadjuvant") therapy was traditionally reserved to render the patient operable. More recently, neoadjuvant therapy, particularly chemotherapy, is being used in patients with operable disease to increase the opportunity for breast conservation. Despite the increasing use of preoperative chemotherapy, rates of pathologic complete response, a surrogate marker for disease-free survival, remain modest in patients with locally advanced disease and particularly so when the tumour is estrogen or progesterone receptor-positive and her2-negative. A new paradigm for labc patients is needed. In other solid tumours (for example, rectal, esophageal, and lung cancers), concurrent chemoradiotherapy (ccrt) is routinely used in neoadjuvant and adjuvant treatment protocols alike. RESULTS: The literature suggests that ccrt in labc patients with inoperable disease is associated with response rates higher than would be anticipated with systemic therapy alone. CONCLUSIONS: Ongoing trials in this field are eagerly awaited to determine if ccrt should become the new paradigm.

How does loss to follow-up influence cohort findings on HIV infection? A joint analysis of the French hospital database on HIV, Mortalité 2000 survey and death certificates.

OBJECTIVE: We aimed to retrieve the vital status of patients lost to follow-up (LFU), with no further visits for at least 12 months, for the 34,835 patients in the Agence Nationale de Recherche sur le SIDA CO4 French Hospital Database on HIV (ANRS CO4 FHDH) seen in 1999 and to examine how loss to follow-up might influence estimates of survival and the impact of delayed access to care (DAC) on survival. METHODS: The status of LFU patients was established by using the mid-2006 update of the FHDH in which their status 12 months after loss to follow-up was added when available and by matching with the Mortalité 2000-Epidemiological Centre for Medical Causes of Death (CépiDc) database, which included HIV-infected patients dying in 2000. We compared Kaplan-Meier and hazard ratio (HR) estimates before and after correction for the status of LFU patients. RESULTS: In the mid-2006 updated FHDH, of the patients seen in 1999, 7.5% were LFU: of these, 2.1% later returned for follow-up, with a median time without follow-up in an FHDH centre of 3.5 years, and 5.4% had no further FHDH visits whatsoever, of whom 29.8% died according to Mortalité 2000-CépiDc. After correction, the estimated 1-year survival rates following enrolment in 1999 differed between the original and updated analyses (97.1 vs. 95.9%, respectively; P=0.017); the estimates of mortality HRs associated with DAC did not differ during the first 6 months, but did differ for the 6-18-month period. CONCLUSIONS: Among LFU patients, 28.1% returned to follow-up after several years and at least 21.4% died, which led to a slight overestimation of both survival and the impact of DAC on survival.

[Inherited primitive and secondary polycythemia]. / Polyglobulies héréditaires primitives et secondaires.

Myeloproliferative disorders and secondary polycythemia cover most of the polycythemia cases encountered in daily practice. Inherited polycythemias are rare entities that have to be suspected when the classical causes of acquired polycythemia have been ruled out. Recent advances were made in the understanding of these pathologies, which are still little known to the physicians. This review reports the state of knowledge and proposes an algorithm to follow when confronted to a possible case of inherited polycythemia.

Allogeneic transplantation for multiple myeloma: further evidence for a GVHD-associated graft-versus-myeloma effect.

We report a series of 37 consecutive patients with multiple myeloma (MM) who received an allograft between 1990 and 2000 at our institution. Median age was 47 years, and nearly 70% of patients were Durie-Salmon stage III. A median of five cycles of chemotherapy were given before transplant, with a median interval between diagnosis and transplant of 9.3 months. We report a nonrelapse mortality rate of 22% with a median follow-up period of 40 months, whereas complete remission (CR) rate at 12 months is estimated at 57%. Treatment failure rate and overall survival at 40 months are estimated at 52% and 32%, respectively. The number of chemotherapy cycles prior to allotransplantation achieved borderline statistical significance as a poor prognosis factor for overall survival (P = 0.05), while the presence of chronic graft-versus-host disease (cGVHD) was significantly correlated with CR achievement (P = 0.036). Our study confirms that early allografting in MM can yield toxicity rates significantly lower than those associated with historical cohorts, and supports the hypothesis that cumulative chemotoxicity has a negative influence on mortality and survival rates. More importantly, our study clearly demonstrates an association between cGVHD and CR and brings further evidence in favor of a graft-versus-myeloma effect.

[Criteria of the diagnosis and treatment of carotid atheromatosis]. / Critères d'investigation et de traitement de l'athéromatose carotidienne.

This retrospective study concerning 102 patients was undertaken to study the therapeutic decisions in these patients when they presented with symptoms of cerebral vascular insufficiency, mostly from the territory of the carotid artery, either transient or accompanied by a deficit. The current literature on the subject is also mentioned. The clinical outcome with regard to the quality of life, seems to have been better in patients who were subjected to carotid endarterectomies than in those who received medical treatment.

Brain abscess due to Petriellidium boydii.

A 22 year-old man died from multiple cerebral abscesses due to Petriellidium boydii 4 1/2 months after an episode of near drowning. The autopsy showed dissemination to heart and kidney. This patient had no immunocompromising disease but was treated with corticosteroids. The treatment of this condition with ventricular shunting and amphotericin B is discussed and compared with the experience of ten other cases reported in the literature.

Extramedullary plasmacytoma associated with angiofollicular lymph node hyperplasia.

We report a case of hyaline-vascular type of angiofollicular lymph node hyperplasia involving the left pulmonary lymph nodes and lung. It clinically presented as an obstruction of the left lower lobe main bronchus secondary to the development of an extramedullary plasmacytoma in the lesion. An immunoperoxidase stain revealed a monoclonal IgG-lambda pattern of the tumor, contrasting with the polyclonal plasma cell population of the angiofollicular lymph node hyperplasia. This case demonstrates the neoplastic potential of angiofollicular lymph node hyperplasia.

Experimental quantum communication without a shared reference frame.

We present an experimental realization of a robust quantum communication scheme [Phys. Rev. Lett. 93, 220501 (2004)] using pairs of photons entangled in polarization and time. Our method overcomes errors due to collective rotation of the polarization modes (e.g., birefringence in optical fiber or misalignment), is insensitive to the phase's fluctuation of the interferometer, and does not require any shared reference frame including time reference, except the need to label different photons. The practical robustness of the scheme is further shown by implementing a variation of the Bennett-Brassard 1984 quantum key distribution protocol over 1 km optical fiber.

Unconditional security of a three state quantum key distribution protocol.

Quantum key distribution (QKD) protocols are cryptographic techniques with security based only on the laws of quantum mechanics. Two prominent QKD schemes are the Bennett-Brassard 1984 and Bennett 1992 protocols that use four and two quantum states, respectively. In 2000, Phoenix et al. proposed a new family of three-state protocols that offers advantages over the previous schemes. Until now, an error rate threshold for security of the symmetric trine spherical code QKD protocol has been shown only for the trivial intercept-resend eavesdropping strategy. In this Letter, we prove the unconditional security of the trine spherical code QKD protocol, demonstrating its security up to a bit error rate of 9.81%. We also discuss how this proof applies to a version of the trine spherical code QKD protocol where the error rate is evaluated from the number of inconclusive events.

An exactly solvable Ogston model of gel electrophoresis. VI. Towards a theory for macromolecules.

In this article, we present a generalized version of our lattice model of low-field gel electrophoresis that allows us to treat the case of macromolecules such as short linear or circular oligomers and semi-flexible rods. We show that free-solution electrophoresis problems can be seen as random walks in the conformational space of the analyte. For sufficiently small molecules, our mathematical approach provides exact mobilities. In a quenched gel-like environment, however, both conformational and positional degrees of freedom must be used, but exact solutions can also be obtained. As an example, we then investigate several two-dimensional model gels, as well as a simple channel system where we see evidence of entropic effects that cannot be captured by the traditional Ogston concept of free volume.

Robust polarization-based quantum key distribution over a collective-noise channel.

We present two polarization-based protocols for quantum key distribution. The protocols encode key bits in noiseless subspaces or subsystems and so can function over a quantum channel subjected to an arbitrary degree of collective noise, as occurs, for instance, due to rotation of polarizations in an optical fiber. These protocols can be implemented using only entangled photon-pair sources, single-photon rotations, and single-photon detectors. Thus, our proposals offer practical and realistic alternatives to existing schemes for quantum key distribution over optical fibers without resorting to interferometry or two-way quantum communication, thereby circumventing, respectively, the need for high precision timing and the threat of Trojan horse attacks.

Treatment of therapy-induced preleukemic syndrome.

Two young adult patients with therapy-induced preleukemic syndrome and Hodgkin's disease as primary malignancy were treated with aggressive antileukemic regimens before the establishment of leukemic conversion. Pretreatment clinical staging procedures did not reveal recurrence of Hodgkin's disease. One of the regimens consisted of an HLA-identical allogeneic bone marrow transplant and the other of high dose cytosine arabinoside. Both therapeutic approaches have proved successful in restoring normal hematopoiesis with reversal to normal karyotypes and unmaintained remissions 556 and 192 days post-treatment. The rationale for such a therapeutic approach in the preleukemic stage of therapy-induced leukemogenesis is discussed.

Robust quantum communication using a polarization-entangled photon pair.

Noise and imperfection of realistic devices are major obstacles for implementing quantum cryptography. In particular, birefringence in optical fibers leads to decoherence of qubits encoded in photon polarization. We show how to overcome this problem by doing single qubit quantum communication without a shared spatial reference frame and precise timing. Quantum information will be encoded in pairs of photons using tag operations, which corresponds to the time delay of one of the polarization modes. This method is robust against the phase instability of the interferometers despite the use of time bins. Moreover synchronized clocks are not required in the ideal no photon loss case as they are necessary only to label the different encoded qubits.