Subdural hygroma: an unwanted result of Sylvian arachnoid cyst marsupialization

INTRODUCTION

Subdural hygroma is a known complication of Sylvian fissure arachnoid cysts (SACs). However, most of the data in the literature refer to spontaneous or posttraumatic occurrence of subdural hygromas, regarded as either a favorable or an unfavorable event. Little is known about this phenomenon as a consequence of the surgical management of SACs. The present study was carried out to evaluate the significance of postoperative subdural hygromas in children with temporal arachnoid cysts, who have been treated with craniotomy and wide marsupialization of the cystic membrane.

CLINICAL MATERIAL AND RESULTS

Between 1980 and March 2002, 104 children were operated on for a SAC at the Pediatric Neurosurgical Unit of the Catholic University Medical School in Rome. Six patients (5.8%; boys/girls=4/2; mean age 3.28 years) developed a subdural hygroma postoperatively, which required further treatment. According to Galassi's classification 4 children had a Type III cyst and 2 children a Type II cyst. All the patients had previously been submitted to open marsupialization of their arachnoid cyst and extensive removal of the cyst wall. In 5 patients (Type III cyst: 4 patients; Type II cyst: 1 patient), acute or subacute symptoms and signs of increased intracranial pressure (ICP) developed at a temporal distance, varying from 5 days to 1 month (mean interval: 14.3 days). All these children needed surgical treatment for the hygroma. A subduro-peritoneal (SDP) shunt was implanted as the first step in 3 patients (Type III cyst: 2 patients; Type II cyst: 1 patient). In the remaining 2 patients of this group (Type III cysts) medical therapy was initially attempted (acetazolamide: 24 mg/kg) without any improvement in clinical manifestations; on these grounds an external spinal subarachnoid drainage was implanted, but led only to the transient clearance of symptoms. The direct drainage of the subdural collection (SDP shunt in 1 patient and temporary external subdural drainage in the other), was followed by complete clinical recovery in both cases. The last patient in this series showed a pathologic increase in head circumference during the 1st month after surgery for his arachnoid cyst, followed by a subsequent stabilization. A CT scan documented a subdural hygroma, which first of all increased in size, but stabilized 2 months after surgery. No surgical treatment was performed in this case. At a mean follow-up of 2.38 years (minimum: 1 month; maximum: 5 years) all the patients are in excellent clinical conditions. Complete neuroradiological resolution of the hygroma was observed in 2 of the 4 shunted patients, who have both been submitted to shunt removal (2 and 3 years after the implant respectively).

CONCLUSIONS

It is our opinion that a wide opening of the external membrane of SACs may predispose the CSF fluid to accumulate within the subdural space, where its absorption is insufficient. A ball mechanism created by CSF pulsation may further increase the subdural fluid accumulation. Secondary distortion and occlusion at the level of the basal cisterns may also contribute to the persistence of the subdural fluid collection. Clinical manifestations may be transient, but frequently have a progressive course and the drainage of the subdural collection is, though transient, required in most cases. On these grounds we suggest the selective opening of the basal cisterns associated with a limited resection of the outer cyst walls in order to limit CSF access to the subdural space.

Triple-q(-->) octupolar ordering in NpO2

We report the results of resonant x-ray scattering experiments performed at the Np M(4,5) edges in NpO2. Below T(0)=25 K, the development of long-range order of Np electric quadrupoles is revealed by the growth of superlattice Bragg peaks. The polarization and azimuthal dependence of the intensity of the resonant peaks are well reproduced assuming anisotropic tensor susceptibility scattering from a triple-q(-->) longitudinal antiferroquadrupolar structure. Electric-quadrupole order in NpO2 could be driven by the ordering at T0 of magnetic octupoles of Gamma(5) symmetry, splitting the Np ground state quartet and leading to a singlet ground state with zero dipole-magnetic moment.

[Investigation on the health of people living near mobile telephone relay stations: I/Incidence according to distance and sex]

A survey study using questionnaire was conducted in 530 people (270 men, 260 women) living or not in vicinity of cellular phone base stations, on 18 Non Specific Health Symptoms. Comparisons of complaints frequencies (CHI-SQUARE test with Yates correction) in relation with distance from base station and sex, show significant (p < 0.05) increase as compared to people living > 300 m or not exposed to base station, till 300 m for tiredness, 200 m for headache, sleep disturbance, discomfort, etc. 100 m for irritability, depression, loss of memory, dizziness, libido decrease, etc. Women significantly more often than men (p < 0.05) complained of headache, nausea, loss of appetite, sleep disturbance, depression, discomfort and visual perturbations. This first study on symptoms experienced by people living in vicinity of base stations shows that, in view of radioprotection, minimal distance of people from cellular phone base stations should not be < 300 m.

Localized 4f states and dynamic Jahn-Teller effect in PrO2

Neutron spectroscopic measurements of the magnetic excitations in PrO2 reveal (1) sharp peaks characteristic of transitions between levels of the 4f(1) configuration of Pr4+ split by the cubic crystal field, and (2) broad bands of scattering centered near 30 and 160 meV. We present a simple model based on a vibronic Hamiltonian that accounts for these contrasting features of the data. The analysis shows that 90%+/-10% of the Pr ions have a localized 4f(1) configuration and provides strong evidence for a dynamic Jahn-Teller effect in the gamma(8) electronic ground state.

[Characterization and distribution of Citrobacter species in a university hospital]

OBJECTIVE

[corrected] a) To identify Citrobacter strains following the conventional biochemical reaction of Brenner and col; b) to evaluate the sensitivity and specificity of the O'Hara's method compared with Brenner's method, and c) to determine the rate and distribution of the strains in the clinical isolates.

MATERIAL AND METHODS

One hundred and twenty two clinical isolates, characterized as Citrobacter spp. were collected between May of 1994 and August of 1997. Clinical isolates included inpatients and outpatients from Hospital de Clínicas. Strains were identified following the methods of Brenner and O'Hara.

RESULTS

Methods of Brenner identified 111 of 122 strains: C. freundii 59 of 111; C. koseri 18 of 111; C. werkmanii 15 of 111; C. braakii 9 of 111; C. youngae 6 of 111 and C. amalonaticus 4 of 111. O'Hara's methods identified 104 of 111 strains (94%). C. freundii was recovered most frequently from urine and feces (p Fisher < 0.026 and 0.039 respectively), while C. koseri was isolated from urine principally (p Fisher < 0.0372).

CONCLUSIONS

The genus Citrobacter is an important opportunistic pathogen that can be identified in clinical microbiology laboratories using O'Hara's method.

Magnetic-octupole order in neptunium dioxide?

The phase transition occurring at 25 K in NpO2, discovered almost 50 years ago, is the most long-lasting mystery in the physics of actinide compounds. Theories based on magnetic or electric-quadrupole order lead inevitably to fundamental, qualitative inconsistencies with observations. We show that the phenomenology of NpO2 can be understood if the order parameter is assumed to be a magnetic octupole of gamma(2) ( xyz) symmetry. NpO2 is the first compound for which indications of an octupolar phase transition have been found.

Body composition changes induced by chronic ethanol abuse: evaluation by dual energy X-ray absorptiometry

OBJECTIVE

Nutritional disorders in alcoholics remain one of the most relevant medical problems in Western societies. As ethanol can supply >50% of the dietary energy in alcoholics, body composition alterations may easily occur. The aim of the present study was to evaluate the influence of chronic alcohol consumption on body composition in alcoholics compared to healthy social drinkers.

METHODS

A total of 34 alcoholics defined according to DSM III R criteria, aged 41.6 +/- 9.3 yr and with a body mass index (BMI) 23.8 +/- 3.2 kg/m2, were consecutively enrolled in the study. In addition, 43 healthy male social drinkers were used as controls. Body composition was assessed using dual energy x-ray absorptiometry (DXA), and dietary habits were determined by a 3-day food diary.

RESULTS

Mean daily alcohol intake was 194 +/- 62.4 g/day in alcoholics and 35.7 +/- 5.2 in healthy subjects (p < 0.0001). Body weight did not differ between alcoholics and controls (70.1 +/- 9.9 vs 71.8 +/- 6.4 kg). Alcoholics had a lower percent body fat (PBF) than control subjects (18.7 +/- 3.7 vs 23.9 +/- 3.9%; p < 0.01), as well as a lower fat mass content (13.4 +/- 3.8 vs 17.0 +/- 3.7 kg; p < 0.01). BMI was highly correlated with PBF in the patient population studied (R = 0.79; p < 0.0001). Significantly higher waist-to-hip ratios were found in alcoholics than in healthy subjects (p < 0.01). No correlation was found between dose of ethanol or duration of alcohol abuse and any of the variables examined.

CONCLUSIONS

Alcoholics showed a reduced fat mass and a good preservation of lean body mass with respect to control subjects, and duration of alcohol use and alcohol dose did not seem to influence body composition. These data suggest that, unlike control subjects, alcoholics cannot store the calories provided by ethanol as fat deposits.

Body composition changes induced by chronic ethanol abuse: evaluation by dual energy X-ray absorptiometry

OBJECTIVE

Nutritional disorders in alcoholics remain one of the most relevant medical problems in Western societies. As ethanol can supply >50% of the dietary energy in alcoholics, body composition alterations may easily occur. The aim of the present study was to evaluate the influence of chronic alcohol consumption on body composition in alcoholics compared to healthy social drinkers.

METHODS

A total of 34 alcoholics defined according to DSM III R criteria, aged 41.6 +/- 9.3 yr and with a body mass index (BMI) 23.8 +/- 3.2 kg/m2, were consecutively enrolled in the study. In addition, 43 healthy male social drinkers were used as controls. Body composition was assessed using dual energy x-ray absorptiometry (DXA), and dietary habits were determined by a 3-day food diary.

RESULTS

Mean daily alcohol intake was 194 +/- 62.4 g/day in alcoholics and 35.7 +/- 5.2 in healthy subjects (p < 0.0001). Body weight did not differ between alcoholics and controls (70.1 +/- 9.9 vs 71.8 +/- 6.4 kg). Alcoholics had a lower percent body fat (PBF) than control subjects (18.7 +/- 3.7 vs 23.9 +/- 3.9%; p < 0.01), as well as a lower fat mass content (13.4 +/- 3.8 vs 17.0 +/- 3.7 kg; p < 0.01). BMI was highly correlated with PBF in the patient population studied (R = 0.79; p < 0.0001). Significantly higher waist-to-hip ratios were found in alcoholics than in healthy subjects (p < 0.01). No correlation was found between dose of ethanol or duration of alcohol abuse and any of the variables examined.

CONCLUSIONS

Alcoholics showed a reduced fat mass and a good preservation of lean body mass with respect to control subjects, and duration of alcohol use and alcohol dose did not seem to influence body composition. These data suggest that, unlike control subjects, alcoholics cannot store the calories provided by ethanol as fat deposits.

Field-dependent energy scales in URu(2)Si(2)

At low temperature, macroscopic properties of URu(2)Si(2) display a characteristic energy scale delta(0)(B) which decreases when a magnetic field is applied, and eventually vanishes at an extrapolated value of the field of about 40 T. We have performed inelastic neutron scattering measurements of the magnetic dynamics of URu(2)Si(2) in applied fields along the c axis of intensities up to 12 T. We show that delta(0)(B) is not related to gaps in the magnetic fluctuations spectra. This provides direct evidence of the fact that two distinct energy scales govern the physics of this compound.

Levy scaling in random walks with fluctuating variance

Truncated Levy flights with correlated fluctuations of the variance (heteroskedasticity) are considered. A stylized model is introduced, in which the variance fluctuates between two possible values following a Markov chain process. Analogously to conventional truncated Levy flights with fixed variance, the central part of the probability distribution function of the increments at short time scales is found to be close to a Levy distribution. What makes these processes interesting is the fact that the crossover to the Gaussian regime may occur for times considerably larger than for uncorrelated (or no) variance fluctuations. Processes of this type may find direct application in the modeling of some economic time series, in which Levy scaling and heteroskedasticity are known to coexist.

["N2" carcinoma of the lung. Therapeutic considerations]

The follow-up of 240 N2 lung cancer cases operated in Thoracic and Cardiovascular Surgery Department of Florence is examined. The analysis is performed in compliance with global survival, "T", histology, therapeutic choices. Global survival is 81% after 6 months, 60% after 1 year, 37% after 2 years, 26% after 3 years, 23% after 4 years, 23% after 5 years. Significative difference on survival does not exist between principal histologic types (squamous, adenocarcinoma, adenosquamous). Raising the "T" survival decreases, but only for adenocarcinoma. Different therapeutic options (only surgery, surgery+radiotherapy, surgery+chemotherapy, surgery+radio and chemotherapy) do not influence the survival in a way statistically significative. From the literature, any certainty about radiotherapy and chemotherapy associated to surgery for N2 lung cancer treatment does not exist at the moment. Thus radical surgery is essential.

[Water disinfection: comparative activities of ozone and chlorine on a wide spectrum of bacteria]

Ozone and chlorine are agents that disinfect by destroying, neutralizing or inhibiting the growth of pathogenic microorganisms. The treatment of drinking water with ozone has shown to be more efficient against spores of Bacillus subtilis. It was observed that the ozone already in dose of 0.35 mg/l produced the reduction of at least 5 log in populations of approximately 1 x 10(6) cells/ml of Escherichia coli, Vibrio cholerae, Salmonella typhi, Yersinia enterocolitica, Pseudomonas aeruginosa, Aeromonas hydrophila, Listeria monocytogenes and Staphylococcus aureus. With a dose of 0.50 mg/l of chlorine, the reduction was much smaller for the tested microorganisms (except Vibrio cholerae), while the effect of 2 mg/l of chlorine was similar to the ozone treatment. For spores of Bacillus subtilis, the reduction observed with ozone concentrations of 0.35 and 0.70 mg/l was of almost 3 log, while no considerable effect was obtained with chlorine in the tested conditions. Our results have shown that both disinfectans were consumed during the treatment period, probably because of the own water demand and the added bacterial mass.

Antimicrobial effect of chlorine on Yersinia enterocolitica

The effects of chlorine at varying pH, culture media and incubation temperatures on one type and two wild type strains of Yersinia enterocolitica were studied. Exposure to 1 and 5 mg 1(-1) did not diminish viability, even after prolonged exposure. A level of 10 mg 1(-1) was required to achieve a 5-log reduction in 120 s for the type strain and 80 s for the wild strains. There was an increase of more than 30% in the rate of disinfection with a 10 degrees C rise, a remarkable increase in antimicrobial activity at pH 5-log reduction in 20 s, as well as marked neutralization of the effect in the presence of 0.1% peptone. Younger cells were more susceptible than older ones, and those from liquid medium more resistant than those from solid medium. Incubation temperature of a 24-h inoculum failed to show any influence. Lastly, there was a noteworthy demand for free chlorine by bacterial biomass, with agreement of the curve depicting the drop in free chlorine in the presence of inoculum with biphasic kinetics of survival curves.

Inappropriate emergency test ordering in a general hospital: preliminary reports

An assessment was made on emergency laboratory test ordering at Udine General Hospital (Italy) to investigate the reasons for the excessive number of requested tests. All the orders for emergency laboratory tests during one week in June 1990 were studied. For each test the time of the order was recorded for every day of the week. The most important aspect of our investigation is the distribution of the orders during the day: in fact, test orders reached two peaks, the upper between 7 and 11 a.m., and the lower between 3 and 6 p.m. The analysis of the record cards showed that 42% of the orders were inappropriate. These preliminary findings were very useful in making the consensus on a Quality Assurance program easier, to improve the use of the Emergency Laboratory by doctors and nurses. Some preliminary results in the Emergency Medicine Department confirmed the validity of this program.

[Idiopathic monoclonal gammopathy. Long-term study of 313 cases]

The records of 519 patients with a paraproteinaemia who where examined at our institutions before January, 1, 1983, were reviewed. After patients with multiple myeloma, macroglobulinemia, amyloidosis, lymphoma or related diseases had been excluded, 363 cases remained which fulfilled the criteria for a diagnosis of idiopathic monoclonal gammopathy (IMG). Also excluded were the cases in which follow-up efforts failed and those in which the paraprotein had disappeared. A long-term study was thus possible in 313 patients with IMG. They were arbitrarily subdivided into two groups: 213 patients with a follow-up of 5-8 years and 100 patients whose follow-up was longer than 8 years. Fourteen per cent of the patients from the former group and 18 per cent from the latter developed a malignant B cell dyscrasia, on the average this event becoming clinically detectable after 63 months (27-138 months) from initial recognition of the paraprotein. A retrospective analysis of the clinical data at the diagnosis of IMG, revealed that none of the patients could have been identified in advance in whom a malignant transformation later occurred.

[Partial and multiple correlations between 4 types of enzymuria in 2 groups of chronic nephropathic patients]

The urinary activity of four enzymes (NAG, GLU, GRS and GAL) was studied in two groups of patients suffering respectively from interstitial nephritis and chronic glomerulonephritis with the aim of further investigating enzyme variability through the theory of partial and multiple correlation. This study permitted the effects of two enzymes on the known correlations between the remaining two enzyme types to be studied. It was established that very stable relationships exist between each enzyme and the group composed of the remaining three. In particular, in patients with interstizial nephritis, correlations with GAL were all highly significant even if the effect of the other two enzymes was ignored. Similarly, correlations with GRS were strongly significant in patients with chronic glomerulonephritis. In the two groups studied, each enzyme appears to have a highly stable relationship with the other three. Accurate estimates may probably be achieved for GAL and GRS in both groups and for NAG in the glomerulonephritis sufferers. This is further evidence that the enzyme procedure may be used to differentiate between interstitial and glomerular nephritis.

[Behavior of 4 urinary enzymes in healthy subjects in relation to age, sex, body weight and height]

105 healthy subjects were studied in order to verify results obtained on a smaller sample and revealed some correlations between NAG and GLU and age. It was also found that in male subjects, GAL tended to vary in relation to body weight and in females in relation to age.

[Normal values of the urinary activity of 4 enzymes]

The urinary activity of 4 enzymes (NAG, GLU, GAL, GRS) was investigated in 105 healthy subjects in order to evaluate the variability of standard levels and establish the degree of such variations in relation to sex, age, weight and height. The results obtained demonstrate that these enzymurias do vary in relation to the parameters examined. Age and sex produced the most pronounced variations though height and body weight also appeared to have some influence. The study of variations in standard levels is of value in the interpretation of pathological enzymurias.

In vitro selective expansion of allergen specific T cells from atopic patients

Peripheral blood mononuclear cells from atopic donors were stimulated in vitro with allergens (Rye group I or Dermatophagoides pteronyssinus). T cell lines were originated and maintained in long term culture using IL-2 and periodical restimulations with allergen. The lines were antigen specific (i.e. responded to the allergen used to raise them and not to other antigens) and required that the antigen was presented by autologous cells (i.e. they were restricted). The restriction elements were probably at the level of HLA-DR antigens since the proliferative response was specifically blocked by anti-HLA-DR antibodies. Surface marker analysis revealed that the lines comprised mainly cells with an helper/inducer phenotype, although cells with markers of the suppressor/cytotoxic T cells were also present. The lines could be cloned by limiting dilution and clones with the same restriction and specificity as the parental line were isolated. These studies demonstrate the possibility of obtaining a large number of allergen specific human T cells that can be used for further in vitro studies on the regulation of the IgE response.

[Comparative study of microbial methods for the detection of genetic toxicity]

It is important to have a rapid and accurate method to detect the toxic action of drugs and chemical compounds used by man. A comparative study with two microbial systems was carried out: one using Salmonella typhimurium and the other using Bacillus subtilis. The 1-8-dihydroxyantraquinone was the tested drug and the N-methyl-N'-nitro-N-nitrosoguanidine and the 2-aminofluorene were used as control substances. These compounds were used as such or after previous transformation by a microsomal system. The results obtained showed that both systems: the S. typhimurium and the B. subtilis work in a similar way, but the latter allows a more direct action of drug on the genetic material. The effect of the solvents: ethanol and dimethylsulfoxide was analysed, because they affected the transformation and reversion processes that were carried out.

[Chromatographic fractionation of cholesterol esters in Morgagni's hepatic cirrhosis. Preliminary note]

The behaviour of plasma cholesteryl esters has been investigated in patients with liver cirrhosis (so-called Laennec's cirrhosis). Both absolute and percentage values of esters containing di-, tri- and tetra-unsaturated fatty acids were decreased below the normal range; however, the various esters groups showed unequal decrement rates. These findings may be the result of a low lecithin: cholesterol-acyltransferase (LCAT) activity, due either to depression of the enzyme syntesis in the liver, or to inadequate substrate supply (possibly related with an impaired fatty acid production and lecithin synthesis). A decrease of all ester fractions, or a selective one, could also be induced by the releasing of abnormal hydrolases from damaged liver tissues.

[Food additives and their possible genetic toxicity; microbiological determination]

In the present work we intend to find an accurat methodology to establish in an easy way the mutagenic potential of drugs employed as food additives. For that purpose we first selected a microbiological system for performing this assay. The method assayed consisted of investigating the effect exerted on genetic recombination by the following chemical agents: Chloroacetic Acid, Iodoacetic Acid, Sorbic Acid, Potassium Metabisulfite, Sodium Nitrite, Auramine and Erythrossine. The activity of these agents was detected though their effect on the transformation of an auxotrophic strain of Bacillus subtilis. Comparative assays of reversion of characters have been made with strains of Salmonella typimurium already used by other authors. These assays have also been repeated with several auxotrophic strains of Bacillus subtilis and different genetic characters have been studied. Most results suggest that changes in the recombination process should have occured at different levels according with the drugs assayed. On the other hand, the results of reversion have not been significant enough. We think that more accuracy is afforded by both the recombination and the reversion assay developed to other for this kind of detection.