Auxiliary device for calibration of roller pumps: development and experimental results.

INTRODUCTION: Roller pumps are commonly used in surgeries involving extracorporeal circulation and its regulation may influence the hemolysis rate. OBJECTIVE: To describe an auxiliary device for adjusting roller pumps using the dynamic calibration method and show preliminary results of its application in surgical procedures. METHOD: The device was tested in the laboratory environment with three disposable pressure transducers normally used in surgeries. In the operation room, tests were carried out with two groups of patients. Free hemoglobin plasma rates were measured, 5 minutes after perfusion started and immediately before the passage of the residual volume of the pump. For Group 1 (n = 22), occlusion measurements were carried out using the drop rate method and for Group 2 (n = 18), measurements were carried out using the auxiliary device and 300 mmHg calibration (mean pressure for the dynamic calibration method). RESULTS: The auxiliary calibration device has shown calibration results statistically equal to those obtained with a reference device in the laboratory environment. We have found less variability of hemolysis rates in the operating room, using the auxiliary device and we did not observe any influence of unbalanced rollers in the hemolysis rates.

[Simultaneous occurrence of neurofibromatosis and tuberous sclerosis, acquired as neo-mutations]. / Ocurrencia simultánea de neurofibromatosis y esclerosis tuberosa, adquiridas como neomutaciones.

INTRODUCTION: Neurofibromatosis type 1 and tuberous sclerosis are two distinct neurocutaneous syndromes that result of a mutation of tumoral suppressor genes, increasing the risk of tumorigenesis. They both have dominant autosomal hereditariness with half of the cases corresponding to new mutations. They are situations rarely associated. CASE REPORT: A boy without any family history of neurocutaneous disorders who had characteristics of both neurofibromatosis and tuberous sclerosis, as cafe-au-lait patches, six greater than 0.5 cm, macrocephaly, optic nerve glioma, focal alterations of the myelin vacuolization of the white matter from both cerebellar hemispheres, brain stem, basal ganglia, characteristic of type 1 neurofibromatosis. He also presented hypopigmentation spots, infantile spasms, and imagiologic findings of cortical areas with altered mielinization on the white matter, left talamo-caudado sulcus calcifications, cortical tubers, Taylor cortical dysplasia, subependimary nodes, characteristically of tuberous sclerosis. The child also had psycho motor development delay. CONCLUSION: The diagnosis of both disorders was confirmed by genetic study. Parents study was negative, so we can confirm the simultaneous occurrence of two new mutations which is unusually rare.

Ocurrencia simultánea de neurofibromatosis y esclerosis tuberosa, adquiridas como neomutaciones / Simultaneous occurrence of neurofibromatosis and tuberous sclerosis, acquired as neo-mutations

La neurofibromatosis tipo 1 y la esclerosis tuberosa son dos síndromes neurocutáneos distintos, resultadode la mutación de genes supresores tumorales, que aumentan la propensión a la génesis tumoral. Ambas tienen una herencia autosómica dominante y la mitad de los casos corresponden a nuevas mutaciones. Estas enfermedades raramente se presentan asociadas. Caso clínico. Niño sin antecedentes familiares de enfermedades neurocutáneas, que presenta característicasde neurofibromatosis y de esclerosis tuberosa, principalmente manchas ‘café con leche’ (seis de ellas con un diámetro superior a 0,5 cm), macrocefalia, glioma del nervio óptico y alteraciones focales de vacuolización de la mielina en la sustanciablanca de los hemisferios cerebelosos, tronco cerebral y ganglios de la base, características de la neurofibromatosis tipo 1. Por otro lado, presenta manchas hipopigmentadas, espasmos infantiles y evaluación imaginológica de las áreas de alteraciónde la mielinización de la corteza para la sustancia blanca, calcificaciones en el surco talamocaudado a la izquierda, tuberosidades corticales, displasia cortical focal de Taylor y múltiples nódulos subependimarios, características que son compatibles con la esclerosis tuberosa. El niño también presenta retraso en el desarrollo psicomotor. Conclusión. El diagnósticode ambas enfermedades se confirmó gracias al estudio genético. La evaluación de los progenitores fue negativa, por lo que se puede confirmar la presencia de dos neomutaciones concomitantes, un hecho que es excepcionalmente raro

Neurofibromatosis type 1 and tuberous sclerosis are two distinct neurocutaneous syndromes thatresult of a mutation of tumoral suppressor genes, increasing the risk of tumorogenese. They both have dominant autosomal hereditariness with half of the cases corresponding to new mutations. They are situations rarely associated. Case report. A boy without any family history of neurocutaneous disorders who had characteristics of both neurofibromatosis and tuberoussclerosis, as café-au-lait patches, six greater than 0.5 cm, macrocephaly, optic nerve glioma, focal alterations of the myelin vacuolization of the white matter from both cerebellar hemispheres, brain stem, basal ganglia, characteristic of type 1 neurofibromatosis. He also presented hypopigmentation spots, infantile spasms, and imagiologic findings of cortical areaswith altered mielinization on the white matter, left talamo-caudado sulcus calcifications, cortical tubers, Taylor cortical dysplasia, subependimary nodes, characteristically of tuberous sclerosis. The child also had psycho motor development delay.Conclusion. The diagnosis of both disorders was confirmed by genetic study. Parents study was negative, so we can confirm the simultaneous occurrence of two new mutations which is unusually rare

In vitro susceptibilities of field isolates of Mycoplasma agalactiae.

In order to determine how widespread antibiotic resistance has become to standard treatments, the in vitro susceptibilities of 28 Mycoplasma agalactiae Spanish field isolates to 16 antimicrobial agents were determined using a broth microdilution method. The most effective antimicrobials based on minimum inhibitory concentration (MIC)(90) values were fluoroquinolones, tetracyclines and macrolides. Two strains were tetracycline resistant. Streptomycin, erythromycin and nalidixic acid resistance was observed in all strains.

In vitro susceptibilities of Mycoplasma putrefaciens field isolates.

MICs were determined for 15 antimicrobial agents against 37 Mycoplasma putrefaciens isolates. The most effective antimicrobial drug classes were the fluoroquinolones, the tetracyclines, the lincosamide lincomycin, and the macrolides. The susceptibility profile of the isolates correlated with the geographic origin. This is the first report of decreased susceptibility to the macrolides, lincomycin, and the tetracyclines in M. putrefaciens strains.

Application of flow cytometry for the determination of minimal inhibitory concentration of several antibacterial agents on Mycoplasma hyopneumoniae.

AIM: In this study, flow cytometry was evaluated for the determination of the minimal inhibitory concentrations (MICs) of nine antibacterial agents (enrofloxacin, ciprofloxacin, oxytetracycline, chloramphenicol, tylosin, lincomycin, gentamycin, spectinomycin and streptomycin) against M. hyopneumoniae. METHODS AND RESULTS: Flow cytometry was able to detect Mycoplasma hyopneumoniae inhibition at 12 h postincubation, whereas the results obtained by the traditional method were only obtained at 48 h, when a visible change in the medium had occurred. At 48 h, both methods gave the same result for eight antibacterial agents, whereas flow cytometry gave slightly higher MIC values for one antibacterial agent (tylosin). This was attributed to the fact that the M. hyopneumoniae growth that had occurred in those tubes was not enough to visibly change the colour of the medium. A good relationship was found between the flow cytometry and the traditional method. CONCLUSION: Flow cytometry was found to be a good method for the determination of antimicrobial MICs in M. hyopneumoniae. SIGNIFICANCE AND IMPACT OF THE STUDY: The flow cytometric method allows the determination of the response of M. hyopneumoniae to each of the antibacterial agents in near real time, and has potential for the identification and study of resistant subpopulations.

In vitro susceptibilities of field isolates of Mycoplasma mycoides subsp. mycoides large colony type to 15 antimicrobials.

In vitro susceptibilities of 16 Mycoplasma mycoides subsp. mycoides large colony type field isolates to 15 antimicrobial agents were determined using a broth microdilution method. The most effective antimicrobials were fluoroquinolones, tetracyclines and macrolides, with MIC values under 2 microg/ml. Resistance to nalidixic acid, gentamicin, streptomycin and spectinomycin was observed.

Use of flow cytometry for enumeration of Mycoplasma mycoides subsp. mycoides large-colony type in broth medium.

AIMS: The potential of using flow cytometry (FC) in combination with a fluorescent dye (SYBR green-I) for rapidly estimating Mycoplasma mycoides subSPS. mycoides large-colony type (MmmLC) in broth culture was examined. METHODS AND RESULTS: The FC analysis was performed by staining the MmmLC cells with a fluorescent dye, SYBR green-I (SYBR), and the results were compared with plate count method (colony forming units, - CFUs). There was a good correlation (linear regression, r(2) = 0.93) between mycoplasma counts determined by FC (cells ml(-1)) and by traditional plate count method (CFU ml(-1)). The lowest bacterial concentration detected by FC and traditional plate count was of the order of 10(4) cells ml(-1) and 10(3) CFU ml(-1), respectively. FC method allowed results in 20-30 min, whereas at least 24 h were necessary to obtain results with the traditional plate count method (CFU). CONCLUSION: Growth rates of MmmLC in broth medium determined by FC were highly reproducible and correlated well with mycoplasma counts assessed by the plate count method. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings suggest that FC could be a good alternative to replace other time-consuming techniques that are currently used to enumerate mycoplasma in broth medium, such as plate count method (CFU).

Fructose-1,6 diphosphate as a protective agent for experimental ischemic acute renal failure.

Cold ischemia time is a risk factor for the development of acute renal failure in the immediate post-transplant period. In this study, we aimed to determine if intravenous fructose-1,6-diphosphate (FDP), given before nephrectomy, attenuates renal cell injury in a cold ischemia model. Male adult Wistar rats were subjected to infusion of either FDP 350 mg/kg (group F, n=6), an equal volume of 0.9% NaCl (group S, n=6), an equal volume/osmolality of mannitol (group M, n=6) or no infusion (group C, n=7). Kidneys were then perfused in situ with Collins solution and nephrectomy was performed. Other kidney slices were stored in Collins solution at 4 degrees C. Adenosine triphosphate (ATP) levels and lactate dehydrogenase (LDH) release were examined at 0, 24, 48 and 72 h. Other slices, obtained after 50 min immersion in Collins solution at 37 degrees C, were frozen for characterization of cytoskeletal preservation using phalloidin-FITC staining. Apical fluorescence intensity of proximal tubule cells, indicative of the F-actin concentration, was measured in a fluorescence microscope interfaced with computer image analysis system. Adenosine triphosphate levels, after up to 72 h of tissue incubation, were higher (P<0.05) in the FDP group when compared to other groups. In addition, LDH release was smaller (P<0.0001) in the FDP group. The F-actin concentration of proximal tubule cells cells was greater in the FDP group (P<0.0001). Results indicate that FDP is a useful tool to increase tissue viability in a rat kidney subjected to cold ischemia, by maintaining ATP cell content, decreasing LDH release and preventing microfilament disruption of proximal tubule cells.

[Tropical spastic paraparesis and HTLV-I associated myelopathy in infancy. A case report and review of the literature]. / Paraparesia espástica tropical/mielopatía asociada al HTLV-I en la infancia. Caso clínico y revisión bibliográfica.

INTRODUCTION: HTLV-I associated myelopathy is characterised by a clinical picture of slowly progressive spastic paraparesis that generally presents when the patient is at an age somewhere between his or her thirties and sixties; few cases have been reported involving children. It is a pathology that is prevalent in tropical regions that are endemic for HTLV-I (southern Japan, the Caribbean, Central and South America, and some areas of Africa). CASE REPORT: The authors report the case of a 9-year-old child from Guinea who was admitted to the Paediatric Neurology Unit in the Hospital de Santa Maria with a two-year-old clinical history of spastic paraparesis. Computerised tomography and magnetic resonance imaging did not show any alterations to the spinal cord. Somatosensory evoked potentials revealed a lesion in the posterior dorsolumbar spinal cord. The exclusion of other (infectious, metabolic and demyelinating) pathologies and the confirmation of infection by HTLV-I (by means of PCR) led to a diagnosis of myelopathy associated to this virus. Therapy was established with interferon alfa, but no appreciable significant improvement was observed. DISCUSSION: This case stands out because of the uncommonness of this pathology at the paediatric age. We review the most relevant aspects of this disorder at the earliest ages, above all with regard to its epidemiology, transmission, clinical symptoms and complementary diagnostic examinations. Known therapeutic options (corticoids, interferon alfa, antiretroviral agents, among others) and prognosis are also discussed.

Paraparesia espástica tropical/mielopatía asociada al HTLV-I en la infancia. Caso clínico y revisión bibliográfica / Tropical spastic paraparesis and HTLV-I associatd myelopathy in infancy. A case report and review of the literature

Introducción. La mielopatía asociada al HTLV-I se caracteriza por un cuadro de paraparesia espástica lentamente progresiva, que se inicia generalmente entre la tercera y la sexta década de la vida, y son raros los casos descritos en niños. Es una patología prevalente en regiones tropicales endémicas para el HTLV-I (sur del Japón, Caribe, América central y del sur y algunas regiones de África). Caso clínico. Se presenta un niño de 9 años, oriundo de Guinea, ingresado en la Unidad de Neurología Pediátrica del Hospital de Santa Maria con un cuadro de paraparesia espática de dos años de evolución. Ni en la tomografía computarizada ni en la resonancia magnética de la médula se detectaron alteraciones. Los potenciales evocados somatosensitivos revelaron una lesión cordonal posterior dorsolumbar. La exclusión de otras patologías, fundamentalmente infecciosas, metabólicas y desmielinizantes, y la confirmación de infección por el HTLV-I (mediante PCR) condujeron al diagnóstico de mielopatía asociada a este virus. Se trató con interferón α, sin apreciarse una mejora significativa. Discusión. Nuestro caso destaca por la rareza de esta patología en la edad pediátrica. Se revisan los aspectos más relevantes de esta patología en las edades más jóvenes, básicamente en lo relativo a su epidemiología, transmisión, manifestaciones clínicas y exámenes complementarios de diagnóstico. Se discuten, incluso, las opciones terapéuticas conocidas (corticoides, interferón α, antirretrovirales, entre otras) y el pronóstico (AU)

Introduction. HTLV-I associated myelopathy is characterised by a clinical picture of slowly progressive spastic paraparesis that generally presents when the patient is at an age somewhere between his or her thirties and sixties; few cases have been reported involving children. It is a pathology that is prevalent in tropical regions that are endemic for HTLV-I (southern Japan, the Caribbean, Central and South America, and some areas of Africa). Case report. The authors report the case of a 9-year-old child from Guinea who was admitted to the Paediatric Neurology Unit in the Hospital de Santa Maria with a twoyear-old clinical history of spastic paraparesis. Computerised tomography and magnetic resonance imaging did not show any alterations to the spinal cord. Somatosensory evoked potentials revealed a lesion in the posterior dorsolumbar spinal cord. The exclusion of other (infectious, metabolic and demyelinating) pathologies and the confirmation of infection by HTLV-I (by means of PCR) led to a diagnosis of myelopathy associated to this virus. Therapy was established with interferon alfa, but no appreciable significant improvement was observed. Discussion. This case stands out because of the uncommonness of this pathology at the paediatric age. We review the most relevant aspects of this disorder at the earliest ages, above all with regard to its epidemiology, transmission, clinical symptoms and complementary diagnostic examinations. Known therapeutic options (corticoids, interferon alfa, antiretroviral agents, among others) and prognosis are also discussed (AU)

Quantum effects after decoherence in a quenched phase transition.

We study a quantum mechanical toy model that mimics some features of a quenched phase transition. Both by virtue of a time-dependent Hamiltonian or by changing the temperature of the bath we are able to show that even after classicalization has been reached, the system may display quantum behavior again. We explain this behavior in terms of simple nonlinear analysis and estimate relevant time scales that match the results of numerical simulations of the master equation. This opens new possibilities both in the study of quantum effects in nonequilibrium phase transitions and in general time-dependent problems where quantum effects may be relevant even after decoherence has been completed.

The spectrum of neurologic disease in children with systemic cancer.

To determine the range of neurologic complications in children with systemic cancer, we evaluated prospectively all of the neurologic consultations requested by the pediatric department of Memorial Sloan-Kettering Cancer Center from October 1997 until January 2001. Demographic data, main complaints, diagnosis, cancer status, etiology, and neuroradiologic studies were reviewed for the 528 consultations. Headache was the most frequent complaint (18.3%), followed by altered mental status (8.4%) and back pain (7.1%). Many children with these complaints had underlying structural disorders despite a normal neurologic examination. The symptoms varied with the underlying cancer and tumor status. Headaches were more common in patients with hematologic cancers, and back pain was more common in patients with solid tumors. Chronic headaches were frequent in patients in remission. Iatrogenic complications, particularly related to chemotherapy, constituted the largest etiologic group (27.7%). A high percentage of neuroradiologic studies were abnormal, and 63% of the magnetic resonance imagine studies were diagnostic. The broad spectrum of conditions underlying the neurologic complaints of children with systemic cancer illustrates the complexity of problems presented by these patients and requires a thorough knowledge of pediatric cancer, its effects on the nervous system, and the complications of its treatment from the neurology consultant.

Cavernous angioma of the brain stem simulating diffuse pontine glioma.

Brainstem vascular malformations can sometimes simulate other conditions such as multiple sclerosis and pontine glioma. We report a case of brainstem cavernous angioma for which clinical course and radiologic appearance were suggestive of a pontine glioma. The diagnosis was uncertain until the clinical and radiologic evolution made it clear that the patient had a cavernous angioma. We suggest that brainstem angioma be considered as a differential diagnosis for pontine glioma.

Intracranial Ewing sarcoma/'peripheral' primitive neuroectodermal tumor of dural origin with molecular genetic confirmation.

Ewing sarcoma/'peripheral' primitive neuroectodermal tumor (ES/pPNET) is the designation given to a family of small cell neoplasms that typically arise in bone or soft tissue and are unified by their common expression of the MIC2 antigen and specific translocations involving a gene on chromosome 22q12 [the most common being t(11;22)(q24;q12)]. ES/pPNET of intracranial origin is extraordinary. We report the case of a 6-year-old boy with a large left frontal region mass that adhered to dura and was extracerebral at surgery. Histologic study revealed a high-grade, undifferentiated-appearing neoplasm of small cell type that was negative on immunostudy for glial fibrillary acidic protein, synaptophysin, desmin, leukocyte common antigen, smooth muscle actin and epithelial membrane antigen, but positive for vimentin and neuron-specific enolase and diffusely labeled by antibody O13 (which recognizes the MIC2 gene product). RNA-based polymerase chain reaction assay confirmed the diagnosis of ES/pPNET by demonstrating fusion transcripts indicative of t(11;22) translocation. Bone scan, computerized tomography of the chest and bone marrow examination revealed no systemic tumor. The limited observations published to date suggest that primary intracranial ES/pPNET is most likely to present in childhood as a circumscribed, contrast-enhancing and dural-based extracerebral mass. It must be distinguished from a variety of small cell neoplasms, particularly PNETs of central neuroepithelial origin.

Opsoclonus-myoclonus-ataxia syndrome in neuroblastoma: clinical outcome and antineuronal antibodies-a report from the Children's Cancer Group Study.

BACKGROUND: Opsoclonus-myoclonus-ataxia (OMA) is a paraneoplastic neurologic syndrome affecting 2-3% of children with neuroblastoma. Although children with OMA and neuroblastoma may have higher survival, many experience a significant amount of late neurologic impairment, which may be immunologically mediated. The aim of this study was to compare the outcome of neuroblastoma patients with and without OMA, relating to prognostic factors, treatment, and the presence or absence of anti-neuronal antibodies. PROCEDURE: Questionnaires were mailed out requesting information on the current neurologic status of patients who submitted sera at diagnosis to the Children's Cancer Group serum bank from 1980 to 1994. Information was requested on clinical and biological patient characteristics as well as clinical aspects of the patients identified as having OMA syndrome, including presentation and treatment for OMA, late sequelae of OMA, the presence or absence of antineuronal antibodies, and survival. Sera from 16 of the OMA patients and 48 case-controls with neuroblastoma were assayed for anti-neuronal antibodies. RESULTS: Of the 675 responses received, 21 patients had OMA. Ninety percent of OMA patients presented with non-metastatic disease, vs. 35% of non-OMA patients. Estimated 3-year survival for the OMA patients with nonmetastatic disease (stage I, II, III) greater than 1 year of age was 100% vs. 77% for similar non-OMA patients (P = 0.0222). At follow-up, 14/19 evaluable OMA patients displayed some form of developmental or neurologic abnormality. There was no significant correlation of late sequelae with antineuronal antibodies, age, time between OMA symptoms and diagnosis, or treatment given for tumor or OMA. There was a significant correlation of late sequelae with lower stage disease (I and II) compared to more advanced disease (III and IV). CONCLUSIONS: Patients with OMA and neuroblastoma have excellent survival but a high risk of neurologic sequelae. Favorable disease stage correlates with a higher risk for development of neurologic sequelae. The role of anti-neuronal antibodies in late sequelae of OMA needs further clarification.

Acute neurologic complications in children with systemic cancer.

Neurologic complications are common in children with cancer, but the literature dealing with this subject is sparse. Using a symptoms and signs approach, the most common causes for requesting a neurologic evaluation for this population are reviewed. The spectrum of neurologic symptoms in children with cancer differs from adults and requires the consulting neurologist to have a thorough knowledge of childhood cancer and its effects on the nervous system.

Targeted radioimmunotherapy for leptomeningeal cancer using (131)I-3F8.

BACKGROUND: Intrathecal antibody-based targeted therapies may have clinical potential for patients with leptomeningeal (LM) cancer. PROCEDURE: Five patients with GD2-positive LM tumors were injected with 1-2 mCi intra-Ommaya (131)I-3F8, a murine IgG3 antibody specific for GD2. Serial cerebrospinal fluid (CSF) and serum samples and SPECT imagings (4, 24, and 48 hr) were performed to predict radiation doses to the tumor and normal brain and blood prior to the administration of larger therapeutic doses. RESULTS: Side effects included self-limited fever, headache, and vomiting. Focal (131)I-3F8 uptake consistent with tumors was seen along the craniospinal axis in four patients. Calculated radiation dose to the CSF was 14.9-56 cGy/mCi and to blood and other organs outside the CNS less than 2 cGy/mCi. CONCLUSIONS: Intraventricular (131)I-3F8 successfully detected LM disease and resulted in a large favorable CSF/blood ratio. Intraventricular (131)I-3F8 may have clinical utility in the diagnosis and radioimmunotherapy of GD2-positive LM cancers. Med. Pediatr. Oncol. 35:716-718. 2000.

Numb chin syndrome in Ewing sarcoma.

The numb chin syndrome consists of unilateral hypesthesia of the chin and lower lip. In adults, it is often associated with metastatic disease to the mandible, base of the skull, or leptomeninges. In children, it has been associated with infiltration of the inferior alveolar nerve by leukemic cells. We describe two cases of numb chin syndrome in children with Ewing sarcoma. In a child with a solid tumor, this symptom seems to have an ominous meaning and should lead to the investigation of progressive skeletal involvement.