Incidence of factor VIII inhibitors in severe haemophilia: the importance of patient age

The potential effect of age at the start of replacement therapy on the development of factor VIII (FVIII) inhibitors was assessed in 62 severe (FVIII < 2 IU/dl) haemophilia A patients who started FVIII therapy at one of two haemophilia centres. Inhibitors were tested on an annual basis. Persistent or high-titre inhibitors were detected in 15 patients (24%). Kaplan-Meier cumulative incidence at 3 years from first FVIII exposure was 41% (95% CI 22-67%) in patients starting therapy before the age of 6 months, 29% (95% CI 13-57%) in patients starting therapy between 6 and 12 months of age, and 12% (95% CI 4-34%) in those starting therapy beyond 1 year of age (P = 0.03). By multivariate analysis, the influence of age was shown to be independent of other variables, including calendar year at the onset of therapy and baseline FVIII plasma levels. In conclusion, patient age at initial treatment appears to influence inhibitor formation. If confirmed, this finding would have a major impact on the management of haemophilia.

Selection of an infectious bursal disease virus mutant with increased immunogenicity following passage under humoral immune pressure

It is generally known that the pathogenicity of infectious bursal disease virus (IBDV) strains decreases following passage in cell culture. However, there is no information about the effect of passage under immune pressure on the phenotypic and molecular properties of IBDV. In the present study, a small plaque mutant virus with poor neutralization capability, but showing similar growth characteristics as the parental virus strain, QC2, was isolated after serial passage in Vero cells in presence of IBDV serotype 1 chicken polyclonal antiserum. This mutant virus showed reduced pathogenicity but enhanced immunogenicity compared to the parental virus. Sequence analysis of the non-coding regions of the genome revealed 4 and 3 nucleotide changes in the 3' non-coding regions of segments A and B, respectively, and none in the 5' non-coding regions. Restriction enzyme analysis of selected coding regions of the IBDV genome in both viruses revealed a loss of the PstI site in the VP2 region of the mutant virus. Selection of such mutant viruses by passaging under immune pressure may offer an improved method for developing safer and more effective attenuated vaccine strains against infectious bursal disease of chickens.

Transoral intratracheal inoculation method for use with neonatal rats

BACKGROUND AND PURPOSE

Studying the effects of toxic and infective compounds on the respiratory system requires a reliable method for delivering inoculum into the distal region of the lung. Although transoral intratracheal inoculation methods have been well documented for adult rats, to the authors' knowledge, a reliable method has not been validated for neonatal rats. The purpose of the study reported here was to develop a simple method for transoral inoculation in rat neonates.

METHODS

Seven-day-old Fischer 344 rats were anesthetized with halothane, and a spinal needle was inserted in the tracheal lumen, by use of illumination and a modified otoscope. Meconium was injected into the lungs as a marker, and the neonates were kept under close observation. After euthanasia at 24 h, lungs were removed and fixed in formalin, and the microscopic distribution of the inoculum was assessed in the left, right cranial, middle, median, and caudal lung lobes.

RESULTS

Microscopic examination of lungs indicated that intratracheal inoculation was achieved in 100% of neonatal lungs and the inoculum was consistently distributed in the alveoli of all pulmonary lobes. Important complications or mortality were not observed in the neonates.

CONCLUSIONS

Intratracheal inoculation of neonatal rats is possible by use of a modified otoscope for transoral illumination. This technique is simple and reproducible and ensures, without complications, widespread distribution of inoculum in the lungs of neonatal rats.

Autologous stem-cell transplantation for Hodgkin's disease: results and prognostic factors in 494 patients from the Grupo Español de Linfomas/Transplante Autólogo de Médula Osea Spanish Cooperative Group

PURPOSE

To analyze clinical outcome and significant prognostic factors for overall (OS) and time to treatment failure (TTF) in a group of 494 patients with Hodgkin's disease (HD) undergoing autologous stem-cell transplantation (ASCT).

PATIENTS AND METHODS

Detailed records from the Grupo Español de Linfomas/Transplante Autólogo de Médula Osea Spanish Cooperative Group Database on 494 HD patients who received an ASCT between January 1984 and May 1998 were reviewed. Two hundred ninety-eight males and 196 females with a median age of 27 years (range, 1 to 63 years) received autografts while in complete remission (n = 203) or when they had sensitive disease (n = 206) or resistant disease (n = 75) at a median time of 26 months (range, 4 to 259 months) after diagnosis. Most patients received high-dose chemotherapy without radiation for conditioning (n = 443). The graft consisted of bone marrow (n = 244) or peripheral blood (n = 250).

RESULTS

The 100-day mortality rate was 9%. The 5-year actuarial TTF and OS rates were 45.0% (95% confidence interval [CI], 39.5% to 50.5%) and 54.5% (95% CI, 48.4% to 60.6%), respectively. In multivariate analysis, the presence of active disease at transplantation, transplantation before 1992, and two or more lines of therapy before transplantation were adverse prognostic factors for outcome. Sixteen patients developed a secondary malignancy (5-year cumulative incidence of 4.3%) after transplantation. Adjuvant radiotherapy before transplantation, the use of total-body irradiation (TBI) in the conditioning regimen, and age > or = 40 years were found to be predictive factors for the development of second cancers after ASCT.

CONCLUSION

ASCT achieves long-term disease-free survival in HD patients. Disease status before ASCT is the most important prognostic factor for final outcome; thus, transplantation should be considered in early stages of the disease. TBI must be avoided in the conditioning regimen because of a significantly higher rate of late complications, including secondary malignancies.

Anisotropic 2-D and 3-D averaging of fMRI signals

A novel method for denoising functional magnetic resonance imaging temporal signals is presented in this note. The method is based on progressively enhancing the temporal signal by means of adaptive anisotropic spatial averaging. This average is based on a new metric for comparing temporal signals corresponding to active fMRI regions. Examples are presented both for simulated and real two and three-dimensional data. The software implementing the proposed technique is publicly available for the research community.

Usefulness and reproducibility of cytomorphologic evaluations to differentiate myeloma from monoclonal gammopathies of unknown significance

We attempted to differentiate monoclonal gammopathies of unknown significance (MGUS) and multiple myeloma (MM) on morphologic grounds and to determine interobserver reproducibility of the differentiation. Cytologists blindly evaluated bone marrow smears from 154 patients with bone marrow plasmacytosis for the proportion of plasma cells with predefined cellular atypias. The single morphologic characteristic that most strongly differentiated MM from MGUS was the presence of nucleoli. The percentage of plasma cells, cytoplasmic contour irregularities, and anisocytosis also predicted a diagnosis of myeloma in multivariate analysis. Six cytologists independently evaluated 68 consecutive cases to determine sensitivity and specificity of these cytomorphologic features. The interobserver coefficient of variation for the plasma cell count was 33%. On consideration of the diagnosis, 36 of 41 MGUS cases and all 24 cases of myeloma were classified correctly. The use of a predesigned score system did not present such a bias, although it did not improve overall efficiency. The plasma cell count is the most predictive characteristic of myeloma from a cytologic viewpoint, but the interobserver variability is high. Interobserver variability is also high in the assessment of morphologic atypia, and atypical traits are not uncommon in plasma cells in MGUS.

[Morphology of peripheral nerves, their sheaths, and their vascularization]

This review aims to update our understanding of peripheral nerves, including the nature and function of their sheaths and, finally, their vascularization. The peripheral nervous system is made up of nerves whose function is to gather stimuli from the periphery as well as to transport the motor, secretory or vegetative responses that are triggered to the periphery. The connective tissue surrounding peripheral nerves all along their extension is made up of endoneurial, perineurial and epineurial. The endoneurium surrounds individual axons, which are grouped in fasciculi, each of which is surrounded by the perineurium and finally, the group of fasciculi that comprise all the axons present in this nerve are surrounded by the epineurium. Axons form an intraneural plexus such that they occupy positions in the various fasciculi along the trajectory of the plexus. The number and size of fasciculi vary along the trajectory of a nerve as a result of the plexus positioning of the axons. Peripheral nerves are richly vascularized throughout their length, with multiple anastomoses forming the intraneural vascular network, which is made up mainly of arterioles, capillaries, postcapillary venules and venules. Regarding the blood-nerve barrier and the existence of capillary permeability: endoneural capillaries have junctions that are stronger than those of the endothelial cells of vessels in the epineurium and perineurium. Two distinct lymph channels networks are present in the peripheral nerve stems and are separated by the perineural barrier. The nervi-nervorum are special nerves of a sympathetic and sensory nature that arise from the nerve itself and the perivascular plexuses.

A rating system for prompt clinical diagnosis of ischemic stroke

BACKGROUND

When a CT scan is not available, an early accurate clinical diagnosis of ischemic stroke is essential to initiate prompt therapy. Our objective was to construct a clinical index that is easy to use when stroke patients are first evaluated at the hospital, to identify those who probably are experiencing an acute ischemic episode. The study was conducted at a university-affiliated medical referral center and two community general hospitals in Mexico.

METHODS

Clinical records were reviewed for 801 patients with sudden onset of a focal or global neurologic dysfunction, presumably of vascular origin lasting more than 24 h. Eligibility criteria for this study were admission to the hospital within the first 24 h after symptomatic onset, CT scan diagnosis between 24 and 72 h, and age >45 years. Ischemic stroke included cases of arterial brain infarction, while nonischemic stroke included subarachnoid or intraparenchymatous hemorrhage, mass lesion, venous infarction, and in cases without a CT scan evidence that could explain the clinical manifestations. Data excerpted for analysis were age, sex, history of diabetes mellitus or previous stroke/transient ischemic attack (TIA), time of onset of symptoms, presence of headache, vomiting, neck stiffness, hemiplegia, leukocytosis or atrial fibrillation, diastolic blood pressure, and Glasgow coma scale (GCS) rating. Two multivariable analyses were used: 1) step-wise multiple logistic regression (SMLR), and 2) conjunctive consolidation (CC).

RESULTS

After appropriate exclusions, the study proceeded with 83 ischemic and 42 nonischemic stroke patients. With SMLR, six variables were selected as predictive for ischemic stroke, including neck stiffness, diastolic blood pressure, previous history of stroke/TIA, hemiplegia, GCS, and atrial fibrillation. An appropriate sum of weighted ratings had a positive predictive value (PPV) of 100% for ischemic stroke. With consolidated categories, the PPV was 97% when patients had the following: no neck stiffness; no atrial fibrillation but history of stroke/TIA and GCS > or =12, or no neck stiffness but atrial fibrillation.

CONCLUSIONS

Among patients with acute stroke, clinical data can be used to identify a group with a high probability of ischemic stroke. There are slightly different results between both methods; while SMLR includes the four variables selected by CC, the latter included neither diastolic blood pressure nor hemiplegia/hemiparesia. However, CC results seem easier to understand and interpret than with SMLR.

Incidence and epidemiology of Citrus tristeza virus in the Valencian community of Spain

The first outbreak of citrus tristeza disease in Spain caused by Citrus tristeza virus (CTV) was recorded in 1957 in the Valencian Community (VC). In total c. 40 million trees, mainly of sweet orange and mandarin grafted on sour orange rootstocks, declined due to CTV. Large-scale surveys in different municipalities of the VC indicated that the disease spread very fast. Incidence increased from 11% in 1989 to 53% in 1998. Toxoptera aurantii and Aphis spiraecola (inefficient aphid vectors of CTV) predominated before 1985-87. Since then the relatively efficient vector Aphis gossypii has become dominant and induced an epidemic that has been modelled. The large number of A.gossypii that visited each clementine tree (estimated to exceed 97000 per year) explained the difference between the temporal pattern of spread of CTV in clementine which followed the Gompertz model and that in sweet orange (logistic model). The susceptibility of the different citrus species to CTV infection by aphids seems to depend on the number of young, succulent shoots produced. The epidemiological data allowed specific recommendations to be made to growers in order to facilitate a change to a modern citrus industry based on the use of selected varieties grafted on tristeza-tolerant rootstocks produced within a certification scheme. This has been done already in almost 90% of the VC citrus-growing area. The tristeza problem has been solved unless more aggressive isolates are introduced and become prevalent.

Alcoholic liver cirrhosis is associated with a decreased expression of the CD28 costimulatory molecule, a lower ability of T cells to bind exogenous IL-2, and increased soluble CD8 levels

Despite the existence of high interleukin (IL)-12 serum levels in patients with chronic active alcoholism, previous studies from our group have shown that, during active ethanol intake, alcoholic patients with alcoholic liver cirrhosis (ALC) display an impaired T-helper-1 response together with abnormalities in the peripheral blood (PB) cytotoxic compartment. The aim of the present study was to gain further insights into the mechanisms underlying these abnormalities. For that purpose, we analyzed the expression on PB B- and T-cell subsets of both the CD28 and CD80 costimulatory molecules, the ability of T lymphocytes to bind to exogenous recombinant IL-2, and the serum levels of soluble CD8 (sCD8) that might interfere with CD8+ T-cell activation in a group of 10 ALC patients with active ethanol intake (ALCET group). As reference groups, we analyzed 10 healthy individuals, 10 chronic alcoholic patients without liver disease (AWLD group) but with active ethanol intake, and 10 ALC patients who had quit drinking for at least 1 year. Our results showed that ALCET patients display a significant decrease in the number of PB CD28+/CD8(hi) T cells (P < 0.05) and CD80+ B cells (P < 0.01) compared with both healthy controls and AWLD patients. In addition, in ALCET patients, PB T cells also showed a decreased ability to bind to exogenous IL-2 (P < 0.01). This was associated with the existence of increased serum levels of sCD8 in ALC patients, the highest levels being detected in the ALCET group (P < 0.01). Altogether, our results point to the existence of several abnormalities that would affect the cytotoxic response in ALCET patients.

Skin necrosis at the injection site induced by low-molecular-weight heparin: case report and review

Heparin-induced skin necrosis at the injection site is a rare adverse effect, more commonly associated with standard heparins than with low-molecular-weight heparins (LMWH) and its mechanism remains unclear. We report a case of LMWH-induced skin necrosis in a female during prophylactic treatment with LMWH after a surgical procedure. Determination of heparin-platelet-factor-4(PF4)-induced antibodies was positive. This case describes the occurrence of LMWH-induced skin necrosis and antibodies to heparin-PF4 complex, suggesting that this effect is more frequent than previously suspected.

Autoimmune thrombocytopenia associated with hepatitis C virus infection

We have retrospectively analyzed a series of 19 patients with hepatitis C virus (HCV) infection and chronic thrombocytopenia not attributable to hypersplenism or to other causes. Antiplatelet antibodies were present in 81% of cases. Response to prednisone was observed in 6 of 7 patients and 1 of 3 patients responded to intravenous immunoglobulins. No case of reactivation of liver disease was observed during or after therapy. We consider that the possibility of an underlying mechanism should be evaluated in thrombocytopenic patients with HCV infection who do not present hypersplenism. These patients could benefit from steroid treatment.

P53 protein expression in gastric adenocarcinoma. Negative predictor of survival after postoperative adjuvant chemotherapy

BACKGROUND

The aim of the present study was to evaluate the influence of p53 protein on the survival of patients undergoing radical gastrectomy and postoperative adjuvant chemotherapy for gastric cancer.

PATIENTS AND METHODS

It was a retrospective study of 46 patients with gastric adenocarcinoma (Stage II and III of the Japanese staging system). Alypatients were treated by curative radical gastrectomy with regional lymphadenectomy plus adjuvant chemotherapy. This regime included Mitomycin (20 mg one hour before surgery, followed by 10 mg the day after) and Fluorinated Pyrimidine (UFT) (400 mg/m2/day orally) (started four weeks after operation, and continued for one year). Immunohistochemical expression of p53 protein was determined on tumor samples from the removed specimens. The influence of p53 on survival was assessed in a Cox's proportional hazard regression analysis.

RESULTS

Sixteen tumors (34.7%) manifested nuclear overexpression of p53 protein. Patients with p53-negative tumors showed higher cumulative survival at 4 years follow-up than patients with p53-positive tumors (82% versus 45%) (p < 0.01). Multivariate analysis identified p53 overexpression as a negative independent predictive factor (hazard ratio: 11.15) (95% CI: 1.93-64.42). Multivariate analysis performed on patients with Stage III tumors, separately, confirmed the predictive effect of p53 overexpression.

CONCLUSION

The results suggest that postoperative adjuvant chemotherapy acted differently in p53-positive than in p53-negative gastric tumors. Absence of p53 overexpression is associated to longer survival when adjuvant therapy is administered.

[Assessment of mediastinal tumor involvement (T factor) in lung cancer with transesophageal ultrasonography]

Transesophageal sonography was originally used to assess esophageal-gastric neoplasm. The technique may also be useful in the evaluation of pulmonary neoplasms for possible mediastinal involvement, with regard to both T and N factors.

OBJECTIVE

To consider the validity of this minimally-invasive technique for assessing possible mediastinal involvement by direct tumoral invasion (T4) and to help obtain the most accurate staging of lung cancer.

PATIENTS AND METHODS

Sixteen patients with confirmed histopathological diagnoses of pulmonary neoplasm were examined by transesophageal sonography in order to evaluate possible mediastinal involvement. They had previously been classified by computed tomography as T4 (12 patients) or possible T4 (4 patients). Mediastinal involvement was also assessed by mediastinotomy or thoracotomy in 15 of the 16 patients.

RESULTS

Transesophageal sonography revealed mediastinal involvement in eight of the 16 patients; the rest had no such involvement. Surgical exploration of the mediastinum confirmed involvement in seven of those who had been so classified by sonography (with the remaining patient not having been assessed surgically). Among the eight patients who were considered free of mediastinal involvement, there was in fact none, although we found previously undetected infiltration of the posterior surface of the right pulmonary artery in one patient. Sensitivity was 87.5%, specificity 100% and accuracy 93.3%.

CONCLUSION

Transesophageal ultrasound is a diagnostic tool that can provide additional information to complement other diagnostic strategies.

Elemental analysis of cetacean skull lesions associated with nematode infections

The elemental composition of both healthy and eroded cetacean skulls associated with nematode infections was evaluated. A total of 27 samples of eroded and non-eroded prepared museum cetacean skulls were characterised by elemental (CHN), X-ray fluorescence, and X-ray diffraction methods. The inorganic composition and crystal line structure (hydroxylapatite-like minerals) were similar for both types of skull samples, but the CHN values clearly differed. The results suggest that the carbon-rich fraction is lost in eroded areas, probably as a result of glycosaminoglycan-degrading Crassicauda enzymes.

[The capacity of the rest-dobutamine gated SPECT protocol to predict contractile recovery after revascularization of myocardial dysinergic areas]

INTRODUCTION AND AIM

Gated-SPECT is a promising method to analyze myocardial viability. We have assessed the accuracy of a new protocol of rest/Dobutamine gated-SPECT, based on the evaluation of contractile reserve induced by 10 microg/kg/min of Dobutamine, to predict contractile recovery after revascularization of dysinergic myocardial territories.

PATIENTS AND METHODS

In a group of 36 patients submitted to percutaneous revascularization, we selected 40 vascular territories (21 left descending artery, 19 right coronary-circumflex) with severely depressed contractility (contrast ventriculography, center line method). Follow up evaluation at 6 months showed the absence of angiographic restenosis and control contrast ventriculography assessed the contractile changes of the selected territories, considering those with contractile restoration as viable. Before revascularization, rest/Dobutamine gated-SPECT study was applied and viability was defined as the presence of contractile reserve (positive or improvement [n = 21] and negative or impairment [n = 7]) with non viability being the absence of contractile reserve (n = 12). We analyzed the evolution of the ejection fraction in a group of 27 patients with impaired ventricular function and complete revascularization.

RESULTS

Gated-SPECT showed a sensitivity of 0.96 (95% CI 0.78-0.99) and a specificity of 0.78 (95% CI 0.48-0.94) in the diagnosis of viability. The ejection fraction (median [interquartile range]) increased after revascularization: 0.42 (0.15) vs 0.55 (0.22), Z = -3.9; p < 0. 001. The diagnosis of viability by gated-SPECT (p < 0.001) and the extent of severely depressed myocardium (p = 0.04) independently predicted the increase of the ejection fraction after revascularization.

CONCLUSIONS

The analysis of contractile reserve by rest/Dobutamine gated-SPECT is adequate to diagnose viability in territories with severely depressed contractility and independently predicts the increase of ejection fraction after revascularization.