A decade of the Catalonian Arthroplasty Register (RACat): Variability, exhaustivity, and survival of prostheses between 2005 and 2014. / Una década del Registro de Artroplastias de Cataluña (RACat): exhaustividad, variabilidad y supervivencia de las prótesis entre 2005 y 2014.

BACKGROUND AND AIM: The Catalonian Arthroplasty Register (RACat) is a public health-based population register used to analyse and evaluate hip and knee replacements in Catalonia. The aim of this study is to present the outcomes after 10 years in operation (January 2005-December 2014). METHODOLOGY: Using the information from the RACat and the minimum basic data set at hospital discharge, an analysis was made of the quality and exhaustivity of the data, as well as a descriptive analysis of the patients, prostheses, and care process. Survival was also analysed by calculating the accumulated incidence of revisions (according to the cause of intervention in hip replacements and conservation or sacrifice of the posterior cruciate ligament in knee replacement). The relationship between revision risk and the fixation technique of the prosthesis is also analysed, using competitive risk models adjusted for gender, age, and comorbidities. RESULTS: The main reason for the primary hip and knee replacement surgery was arthrosis. The accumulated incidence of revisions at 10 years was 3.9% in hip replacements caused by arthrosis, and 2.3% in those caused by fracture. Conservation of the posterior cruciate ligament was achieved in 4.4% of knee replacements, with sacrifice in 5.1%. DISCUSSION: The RACat is consolidated as a tool for the evaluation of joint replacements, with great potential in the analysis of medium and long-term efficacy, the study of the variability in clinical practice, and post-marketing surveillance.

COMT Val158Met polymorphism in relation to activation and de-activation in the prefrontal cortex: A study in patients with schizophrenia and healthy subjects.

The Val158Met polymorphism in the COMT gene has been found to be associated with differences in brain activation in both healthy subjects and patients with schizophrenia. The predominant finding has been increased prefrontal activation associated with the Val allele; however, genotype-related de-activations have not been studied. In this study 42 schizophrenia patients and 31 controls underwent fMRI while performing the n-back task. Brain differences related to presence/absence of disease and presence/absence of the Val/Val genotype were examined. Both disease and Val/Val genotype were associated with failure of de-activation in a cluster centred in the medial prefrontal cortex. There was no interaction between disease and genotype at this location, but clusters where there were significant interactions emerged in the right prefrontal cortex and left temporal/parietal cortex. These findings suggest that Val158Met polymorphism influences task-related de-activations in the default mode network in both healthy subjects and schizophrenia patients to an equivalent extent. However the Val158Met polymorphism also has disease-specific effects on DLPFC activation in schizophrenia.

Medial prefrontal cortex pathology in schizophrenia as revealed by convergent findings from multimodal imaging.

Neuroimaging studies have found evidence of altered brain structure and function in schizophrenia, but have had complex findings regarding the localization of abnormality. We applied multimodal imaging (voxel-based morphometry (VBM), functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) combined with tractography) to 32 chronic schizophrenic patients and matched healthy controls. At a conservative threshold of P=0.01 corrected, structural and functional imaging revealed overlapping regions of abnormality in the medial frontal cortex. DTI found that white matter abnormality predominated in the anterior corpus callosum, and analysis of the anatomical connectivity of representative seed regions again implicated fibres projecting to the medial frontal cortex. There was also evidence of convergent abnormality in the dorsolateral prefrontal cortex, although here the laterality was less consistent across techniques. The medial frontal region identified by these three imaging techniques corresponds to the anterior midline node of the default mode network, a brain system which is believed to support internally directed thought, a state of watchfulness, and/or the maintenance of one's sense of self, and which is of considerable current interest in neuropsychiatric disorders.

Creatine transporter deficiency in two adult patients with static encephalopathy.

Creatine transporter deficiency is a recently identified X-linked inborn error of metabolism. The natural course of the disease is not well delineated since clinical data from adult patients have scarcely been reported. A progressive course of the disease has been noted in a few described cases. We report the first two Spanish adult patients with creatine transporter deficiency and compare their clinical phenotype and the evolution of the disease with those of other published cases. The two brothers were identified in a study of a cohort of 610 mentally handicapped male patients. The disease was detected by biochemical studies and confirmed by DNA studies. The most significant clinical features were mental retardation, epilepsy and autistic behaviour, and these symptoms did not worsen, in contrast to other reports. They did not present gastrointestinal problems or movement disorders. Creatine transporter deficiency could be an underdiagnosed metabolic disorder and should be considered in adult patients with mental retardation. Clinical presentation of this disorder showed marked differences among adult patients and the course of the disease was static in our cases. Detection of additional adult patients might allow better understanding of the phenotypic outcome at a later age.

[Renal dynamics: comparison between diuretic renogram and magnetic resonance imaging]. / Dimámica renal: comparación entre el renograma diurético y la resonancia magnética.

OBJECTIVE: This study aimed to establish a comparison between the data obtained in the renal functional study through magnetic resonance using gadolinium with diuretic (furosemide) charge (MR-Gd/F), on the one hand, and the parameters obtained with the classical diuretic renogram (DR) (differential renal function -DRF- and renographic curve -RC-), on the other hand. MATERIAL AND METHOD: 10 patients were studied, 6 male and 4 female, aged between 1 month and 6 year-old. All the patients were submitted to a MR-Gd/F and a DR. In both cases, furosemide was used as overload. The pathologies observed included syndrome of the pyeloureteral junction, polar vessel, ureter valve, ectopic ureter, duplex kidney, renal dysplasia, renal ectasy, pelvic kidney and horseshoe kidney. The percentage of gadolinium uptake was compared versus the DRF, and the MR curve was compared versus the RC. Surgical treatment was required in 5 cases and an expectancy behaviour was taken in 3 cases. Among the operated patients, the diagnosis accurry was confirmed by the surgery and the pathological study. RESULTS: A 80% consistency was found between the gadolinium uptake and the DRF. There was a 90% correlation between the MR-Gd/F curve and the RC. In two cases, the MR-Gd/F required to modify the surgical criterion -previously based on the DR- and an expectancy behaviour was taken. In 90% of the operated cases, the diagnostic assumption obtained through the MR-Gd/F coincided with the surgical and pathological findings, whereas there was a coincidence in just 60% of the cases studied through the DR (p > 0.0008). CONCLUSIONS: The MR offers a real time study: anatomical, vascular and functional. Good correlation between DR and MR with respect to: (% DRF,%Gd MR and diuretic curve). The MR demonstrates greater precision in diagnosis.The MR allows recognition of non obstructive polar vessels that can then be conservatively managed.

Stage 1B cervical cancer in a pregnant woman at 25 weeks of gestation.

Cervical cancer associated with pregnancy is rare (0.05%), although it is the most frequently diagnosed malignancy in pregnant women. We present the case of a 28-year-old woman at 25 weeks of gestation diagnosed with Stage 1B cervical cancer. Treatment was delayed until fetal maturity, and an elective cesarean section was performed at 33 weeks' gestation, followed by a total hysterectomy preserving the ovaries, and a pelvic lymphadenectomy. A review of the literature on the treatment of cervical cancer during pregnancy relevant to the case described is also presented.

Failure to deactivate in the prefrontal cortex in schizophrenia: dysfunction of the default mode network?

BACKGROUND: Functional imaging studies using working memory tasks have documented both prefrontal cortex (PFC) hypo- and hyperactivation in schizophrenia. However, these studies have often failed to consider the potential role of task-related deactivation. METHOD: Thirty-two patients with chronic schizophrenia and 32 age- and sex-matched normal controls underwent functional magnetic resonance imaging (fMRI) scanning while performing baseline, 1-back and 2-back versions of the n-back task. Linear models were used to obtain maps of activations and deactivations in the groups. RESULTS: The controls showed activation in the expected frontal regions. There were also clusters of deactivation, particularly in the anterior cingulate/ventromedial PFC and the posterior cingulate cortex/precuneus. Compared to the controls, the schizophrenic patients showed reduced activation in the right dorsolateral prefrontal cortex (DLPFC) and other frontal areas. There was also an area in the anterior cingulate/ventromedial PFC where the patients showed apparently greater activation than the controls. This represented a failure of deactivation in the schizophrenic patients. Failure to activate was a function of the patients' impaired performance on the n-back task, whereas the failure to deactivate was less performance dependent. CONCLUSIONS: Patients with schizophrenia show both failure to activate and failure to deactivate during performance of a working memory task. The area of failure of deactivation is in the anterior prefrontal/anterior cingulate cortex and corresponds to one of the two midline components of the 'default mode network' implicated in functions related to maintaining one's sense of self.

Early and late complications among 15 victims exposed to indoor fire and smoke inhalation.

AIM: To evaluate early and late complications among victims exposed to indoor fire and smoke inhalation. METHOD: An observational, descriptive and prospective longitudinal study of 15 victims of smoke inhalation admitted to the intensive care unit. RESULTS: Although without significant burns, 13 of the victims were unconscious, with airway injury, abnormal temperature and hypokalaemia, and underwent mechanical ventilation. Initial carbon monoxide concentration averaged 20.4+/-8.3%, dropping to 3.9+/-3.3% 4h later. On the 1st day, two victims recovered and were transferred, and another two died. Creatine kinase levels (2594+/-2455 U/l) correlated with duration of intensive care. Of the remaining 11 patients, 10 had early pneumonia. Steroid treatment was initiated for four patients receiving prolonged mechanical ventilation, because of persistent fever and dry cough without evidence of infection. CONCLUSIONS: Mortality and systemic involvement were related to burn of the upper airway and contact with combustion products. Initial creatine kinase levels emerged as a prognostic marker of injury severity. Bronchoscopy was useful in grading airway injury and obtaining bronchoalveolar culture. Corticosteroids were effective, after the acute phase, in treating non-infectious pulmonary complications.

A simple view of the brain through a frequency-specific functional connectivity measure.

Here we develop a measure of functional connectivity describing the degree of covariability between a brain region and the rest of the brain. This measure is based on previous formulas for the mutual information (MI) between clusters of regions in the frequency domain. Under the current scenario, the MI can be given as a simple monotonous function of the multiple coherence and it leads to an easy visual representation of connectivity patterns. Computationally efficient formulas, adequate for short time series, are presented and applied to functional magnetic resonance imaging (fMRI) data measured in subjects (N=34) performing a working memory task or being at rest. While resting state coherence in high (0.17-0.25 Hz) and middle (0.08-0.17 Hz) frequency intervals is bilaterally salient in several limbic and temporal areas including the insula, the amygdala, and the primary auditory cortex, low frequencies (<0.08 Hz) have greatest connectivity in frontal structures. Results from the comparison between resting and N-back conditions show enhanced low frequency coherence in many of the areas previously reported in standard fMRI activation studies of working memory, but task related reductions in high frequency connectivity are also found in regions of the default mode network. Finally, potentially confounding effects of head movement and regional volume on MI are identified and addressed.

[Comparison between MRI and the techniques traditionally used in the study of uropathies in children]. / Análisis prospectivo y comparativo entre la resonancia magnética y las exploraciones tradicionales utilizadas en el estudio de las uropatías con afectación funcional del niño.

BACKGROUND: To correlate the anatomical and functional information obtained using MRI in comparison to the techniques traditionally used in the study of uropathies, and to compare their physical and socioeconomic impacts. METHODS: For a period of eleven months we carried out a prospective study of 22 patients of both sexes ranging in age from 1 to 180 months. All suffered from one or another uropathy. Fifty-five percent of the patients were from external consultation while 45% had been diagnosed prenatally. The imaging techniques compared with MRI were as follows: echography, renogram, renal DMSA scan, urography and cystography. For the MRI gadolinium was used, as well as general anesthesia in some cases. RESULTS: There was a significant correlation (r = 0.942 p < 0.01) between MRI and the traditional explorations for the diagnosis of hydronephrosis, horseshoe kidney, kidney duplication, kidney hypoplasia and hypertrophy, multicystic kidney, ureterocele, pyeloureteral stenosis, vesicoureteral stenosis, atrophy of the renal artery, and missing kidney. It was not useful for reflux. Comparing to renal function differential on renogram there was an 86% agreement between the results. The average number of visits was 5.7 and missed workdays 4.1. The cost as a result of MRI was less than that for other explorations (Chi2 = 27,909 p < 0.001). CONCLUSIONS: MRI provides the same information, both morphological and concerning functional quality, as well as vascular, as that obtained through traditional explorations. Irradiation with MRI is nil. At times it requires anesthesia. Its practice reduces costs, visits, missed workdays, and travel time. In the future it could probably be possible to carry out cystography and hydric/diuretic overload testing at the same time, the efficacy will be increased.

Plasma S-adenosylhomocysteine is a more sensitive indicator of cardiovascular disease than plasma homocysteine.

BACKGROUND: Although plasma total homocysteine has been identified as an independent risk factor for vascular disease in a multitude of studies, there is a considerable overlap in values between patients at risk and control subjects. The difference in values can be used to distinguish statistically between the 2 groups, provided each group is large enough; however, discriminating between individual patients at risk and control subjects is difficult. OBJECTIVE: We investigated whether the precursor of homocysteine, S-adenosylhomocysteine, is a more sensitive indicator of risk. DESIGN: We measured plasma total homocysteine, S-adenosylhomocysteine, S-adenosylmethionine, creatinine, folate, and vitamin B-12 in 30 patients with proven cardiovascular disease and 29 age- and sex-matched control subjects. RESULTS: The homocysteine values (+/-SD) were 12.8 +/- 4.9 (95% CI: 11.0, 14.7) micromol/L for patients and 11.0 +/- 3.2 (9.8, 12.2) micromol/L for control subjects. The S-adenosylhomocysteine values were 40.0 +/- 20.6 (32.3, 47.7) nmol/L for patients and 27.0 +/- 6.7 (24.5, 30.0) nmol/L for control subjects (P = 0.0021). The S-adenosylmethionine values were 121.8 +/- 42.9 (105.8, 137.8) nmol/L for patients and 103.9 +/- 21.8 (95.6, 112.2) nmol/L for control subjects (P = 0.0493). The creatinine values were 110 +/- 27 (97, 120) micromol/L for patients and 97 +/- 9 (80, 100) micromol/L for control subjects (P = 0.0025). Values for folate and vitamin B-12 did not differ significantly between groups. CONCLUSIONS: Plasma S-adenosylhomocysteine appears to be a much more sensitive indicator of the difference between patients with cardiovascular disease and control subjects than is homocysteine. Both plasma total homocysteine and S-adenosylhomocysteine are significantly correlated with plasma creatinine in patients.

A prototype decision support system for MR spectroscopy-assisted diagnosis of brain tumours.

Our objective is to develop a decision support system that improves the accuracy of non-invasive brain tumour diagnosis and grading by enabling radiologists to use data from Magnetic Resonance Spectroscopy (MRS). The system, which uses pattern recognition techniques, is trained on a validated database of spectra and associated clinical information to provide automated classification of spectra from brain tumours. An innovative user-interface presents classification results as a two-dimensional overview plot in which points representing cases of different diseases form distinct clusters. Users can inspect any cases in these plots and compare them with the new, unknown spectrum. Hence, the overview plot can both communicate the classification of a case and help provide explanation for that classification in part by supporting human case-based reasoning. This paper describes the development of a prototype system implemented in JAVA.

Glycine N-methyltransferase deficiency: a novel inborn error causing persistent isolated hypermethioninaemia.

This paper reports clinical and metabolic studies of two Italian siblings with a novel form of persistent isolated hypermethioninaemia, i.e. abnormally elevated plasma methionine that lasted beyond the first months of life and is not due to cystathionine beta-synthase deficiency, tyrosinaemia I or liver disease. Abnormal elevations of their plasma S-adenosylmethionine (AdoMet) concentrations proved they do not have deficient activity of methionine adenosyltransferase I/III. A variety of studies provided evidence that the elevations of methionine and AdoMet are not caused by defects in the methionine transamination pathway, deficient activity of methionine adenosyltransferase II, a mutation in methylenetetrahydrofolate reductase rendering this activity resistant to inhibition by AdoMet, or deficient activity of guanidinoacetate methyltransferase. Plasma sarcosine (N-methylglycine) is elevated, together with elevated plasma AdoMet in normal subjects following oral methionine loads and in association with increased plasma levels of both methionine and AdoMet in cystathionine beta-synthase-deficient individuals. However, plasma sarcosine is not elevated in these siblings. The latter result provides evidence they are deficient in activity of glycine N-methyltransferase (GNMT). The only clinical abnormalities in these siblings are mild hepatomegaly and chronic elevation of serum transaminases not attributable to conventional causes of liver disease. A possible causative connection between GNMT deficiency and these hepatitis-like manifestations is discussed. Further studies are required to evaluate whether dietary methionine restriction will be useful in this situation.

Right prefrontal repetitive transcranial magnetic stimulation in obsessive-compulsive disorder: a double-blind, placebo-controlled study.

OBJECTIVE: The efficacy of repetitive transcranial magnetic stimulation (rTMS) of the right prefrontal cortex for patients with obsessive-compulsive disorder (OCD) was studied under double-blind, placebo-controlled conditions. METHOD: Patients were randomly assigned to 18 sessions of real (N=10) or sham (N=8) rTMS. Treatments lasted 20 minutes, and the frequency was 1 Hz for both conditions, but the intensity was 110% of motor threshold for real rTMS and 20% for the sham condition. RESULTS: No significant changes in OCD were detected in either group after treatment. Two patients who received real rTMS, with checking compulsions, and one receiving sham treatment, with sexual/religious obsessions, were considered responders. CONCLUSIONS: Low-frequency rTMS of the right prefrontal cortex failed to produce significant improvement of OCD and was not significantly different from sham treatment. Further studies are indicated to assess the efficacy of rTMS in OCD and to clarify the optimal stimulation characteristics.

The value of endorectal MR imaging to predict positive biopsies in clinically intermediate-risk prostate cancer patients.

The aim of this study was to assess the effectiveness of endorectal MR imaging in predicting the positive biopsy results in patients with clinically intermediate risk for prostate cancer. We performed a prospective endorectal MR imaging study with 81 patients at intermediate risk to detect prostate cancer between January 1997 and December 1998. Intermediate risk was defined as: prostatic specific antigen (PSA) levels between 4 and 10 ng/ml or PSA levels in the range of 10-20 ng/ml but negative digital rectal examination (DRE) or PSA levels progressively higher (0.75 ng/ml year(-1)). A transrectal sextant biopsy was performed after the endorectal MR exam, and also of the area of suspicion detected by MR imaging. The accuracies were measured, both singly for MR imaging and combined for PSA level and DRE, by calculating the area index of the receiver operating characteristics (ROC) curve. Cancer was detected in 23 patients (28%). Overall sensitivity and specificity of endorectal MRI was 70 and 76%, respectively. Accuracy was 71% estimated from the area under the ROC curve for the total patient group and 84% for the group of patients with PSA level between 10-20 ng/ml. Positive biopsy rate (PBR) was 63% for the group with PSA 10-20 ng/ml and a positive MR imaging, and 15% with a negative MR exam. The PBR was 43% for the group with PSA 4-10 ng/ml and a positive MR study, and 13% with a negative MR imaging examination. We would have avoided 63% of negative biopsies, while missing 30% of cancers for the total group of patients. Endorectal MR imaging was not a sufficient predictor of positive biopsies for patients clinically at intermediate risk for prostate cancer. Although we should not avoid performing systematic biopsies in patients with endorectal MR imaging negative results, as it will miss a significant number of cancers, selected patients with a PSA levels between 10-20 ng/ml or clinical-biopsy disagreement might benefit from endorectal MR imaging.

Magnetic resonance spectroscopy of brain hemangiopericytomas: high myoinositol concentrations and discrimination from meningiomas.

OBJECT: Hemangiopericytomas are a rare type of brain tumor that are very similar to meningiomas in appearance and symptoms but require different treatment. It is not normally possible to distinguish between them by using magnetic resonance (MR) imaging and computerized tomography studies. However, discrimination may be possible by using in vivo MR spectroscopy (MRS) because the biochemical composition of these two lesions is different. The goal of this study was to describe the use of MRS in discriminating between these similar tumor types. METHODS: In vivo MRS spectra were acquired in 27 patients (three with hemangiopericytomas and 24 with meningiomas) by using a single-voxel proton brain examination system at 1.5 teslas with short- (20-msec) and long- (135-msec) echo times. In addition, brain biopsy specimens obtained by open craniotomy were frozen within 5 minutes of resection and stored in liquid nitrogen until they were used. The specimens were powdered, extracted with perchloric acid, redissolved in 2H2O2 and high-resolution in vitro MRS was used at 9.4 teslas to record their spectra. CONCLUSIONS: In this study the authors show that hemangiopericytomas could be clearly distinguished from meningiomas because they have a larger peak at 3.56 ppm. Measurements of extracts of the tumors and comparison of spectra acquired with MRS at long- (135-msec) and short- (20-msec) echo times established that this was due to the much higher levels of myoinositol in the hemangiopericytomas.

The effect of medial frontal and posterior parietal demyelinating lesions on stroop interference.

Functional imaging has consistently shown that attention-related areas of medial frontal and posterior parietal cortices are active during the attentional conflict induced by color naming in the presence of distracting words (Stroop task). Such studies, however, have provided few details of the correlational nature between observed regional brain activations and reaction time delay occurring in this situation. We analyzed the effect of medial frontal and posterior parietal lesions on the Stroop response in a group of patients with multiple sclerosis, a neurological disorder in which Stroop response speed is affected to varying degrees. Forty-five patients were assessed using a computer-presented verbal version of the Stroop task and specific MRI protocol. Demyelination areas were measured on five anatomical divisions of the medial frontal white matter and on white matter of the posterior parietal lobe. We found that a combination of frontal and parietal lesion measurements accounted for 45% of the Stroop interference time variance. Patients with more right frontal than left parietal demyelination showed slowed Stroop responses, whereas the predominance of lesions in the left posterior parietal region was associated with a reduced Stroop interference. These results may contribute to defining the specific participation of these attention-related brain areas in the conflict of attention represented by the Stroop paradigm. They also help to explain the variability of the Stroop effect in multiple sclerosis patients and suggest that the Stroop test does not assess just a single cognitive operation, but rather the combined effect of anatomically segregated neural processes.

Beck Depression Inventory factors related to demyelinating lesions of the left arcuate fasciculus region.

This study was conducted to further establish the significance of the previously reported association between depressive symptoms and demyelinating lesions in the region of the left arcuate fasciculus in multiple sclerosis patients. The Beck Depression Inventory (BDI) was broken down into its main symptom categories on the basis of well-established factor analyses from the literature, and the correlation pattern between the resulting BDI subscores and lesion measurements was analyzed. We found that lesions of the left arcuate fasciculus region were selectively associated with BDI items expressing patients' Affective Symptoms and Somatic Complaints. Specifically, lesion measurements from this brain location accounted for 26% of symptom score variance of the BDI part that includes only these two factors. Performance Difficulties and Cognitive Distortions were not consistently associated with the lesion measurement. Performance Difficulties, however, showed a high correlation with the neurologic deficit detected in the physical examination. These results show that lesions in the left arcuate fasciculus region are associated with the core of the depressive syndrome rather than marginal symptoms and, thus, further suggest that this left suprainsular brain region involves white matter tracts relevant to mood regulation.