Quartz dustiness: A key factor in controlling exposure to crystalline silica in the workplace.

The classification of Respirable Crystalline Silica (RCS) as carcinogenic for humans has drawn greater attention to crystalline silica exposure in the workplace in recent years, leading to recommendations by safety and health bodies in Europe and the U.S. for lower occupational exposure limits. In view of this new scenario, the present study examined quartz dustiness, as quartz handling is a major source of crystalline silica in the workplace. The study was conducted on test samples with different mean particle sizes, prepared from several commercial quartzes. The quartz particle samples were characterised and the influence of certain quartz particle parameters on quartz dustiness was determined. The results indicate that quartz dustiness may be significantly affected by mean particle size, specific surface area, the Hausner ratio, and fine particle content. The study shows that, in order to minimise the adverse health effects associated with the inhalation of crystalline silica, quartz dustiness may be deemed a key factor in controlling the generation of fugitive quartz emissions during quartz processing, both into the outside atmosphere (air pollution) and inside the facilities (occupational health).

Optimal excitation and emission wavelengths to analyze amino acids and optimize neurotransmitters quantification using precolumn OPA-derivatization by HPLC.

We describe an analytical methodology to obtain high sensitivity and better resolution through the study of fluorometric excitation (λex) and emission (λem) spectrum wavelengths of OPA-amino acids. The spectrum emission study revealed a maximum signal peak at 450 nm for aspartate and glutamine. For glycine, taurine, and GABA, the maximum signal peak was at 448 and for glutamate at 452 nm. The remaining amino acids analyzed showed a maximum emission around 450 nm. The best signal obtained within the spectrum excitation experiments was using 229- to 450-nm λex-λem. The drawbacks observed at these wavelengths were a baseline drift and negative peaks occurrence. Thus, the excitation wavelength of 240 nm was chosen (240- to 450-nm λex-λem) as a compromise between a very good signal response and a baseline stability to resolve the 18 amino acids studied. Furthermore, this protocol was properly validated. On the other hand, the elution gradient program used for neuroactive amino acids (aspartate, glutamate, glycine, taurine and GABA) showed separation to the baseline, in a 15-min run in all of them. Other amino acids, up to 18, also exhibited a very good separation in a 25-min run. In conclusion, we propose the use of 240- to 450-nm λex-λem wavelengths, in OPA-amino acids analysis, as the most suitable protocol to obtain the best signal response, maintaining an optimum chromatographic resolution.

Plasma progranulin levels in cortical dementia phenotypes with asymmetric perisylvian atrophy.

BACKGROUND AND PURPOSE: Decreased plasma progranulin levels are a very specific marker for the diagnosis of frontotemporal lobar degeneration (FTLD) caused by mutations in the progranulin gene (GRN). A frequent neuroimaging pattern in this type of dementia is asymmetric cortical atrophy. The aim of this study was to screen for GRN-linked FTLD in cases with different cortical dementia phenotypes and asymmetric perisylvian atrophy. METHODS: Progranulin plasma levels were analyzed in a variety of FTLD phenotypes (n = 71), dementia of the Alzheimer type (DAT) (n = 22) and probable Lewy body dementia (n = 8), both latter groups presented with asymmetric perisylvian atrophy. A group of elderly controls (n = 29) and DAT cases with symmetric atrophy (n = 33) were also analyzed. The GRN gene was sequenced in cases with lower plasma levels. RESULTS: Four cases with clinical FTLD phenotypes and plasma levels below 70 ng/ml were found to carry different GRN mutations: M1?, C139R, a point mutation in the splice donor site of intron 3 (A89VfsX41), and a deletion in exon 9 (A303AfsX57), this latter one being a new mutation. Thirteen cases with levels between 72 and 85 ng/ml did not show pathogenic changes in the GRN gene. None of the cases with asymmetric atrophy and clinical phenotypes other than FTLD had GRN mutations. CONCLUSIONS: Asymmetric perisylvian atrophy is not likely to predict progranulin-linked FTLD unless it is associated with a consistent FTLD clinical phenotype.

Seaweed as a source of novel nutraceuticals: sulfated polysaccharides and peptides.

Seaweeds and seaweed-derived products are underexploited marine bioresources and a source of natural ingredients for functional foods. Nutritional studies on seaweeds indicate that brown and red seaweeds possess a good nutritional quality and could be used as an alternative source of dietary fiber, protein, and minerals. Moreover, bioactive sulfated polysaccharides are the main components of soluble fiber in seaweeds and also bioactive peptides can be prepared from seaweed protein. This chapter gives an overview of the main biological properties of sulfated polysaccharides and peptides from brown and red seaweeds. Recent studies have provided evidence that sulfated polysaccharides from seaweeds can play a vital role in human health and nutrition. Besides, peptides derived from algal protein are most promising as antihypertensive agents. Further research work, especially in vivo studies, are needed in order to gain a better knowledge of the relation structure-function by which bioactive compounds from seaweeds exert their bioactivity.

Simple estimates of vehicle-induced resuspension rates.

Road dust emissions are considered to be a major source of airborne particulate matter (PM). This is particularly true for industrial environments, where there are high resuspension rates of deposited dust. The calculation of roads as PM emission sources has mostly focused on the consequences of this emission, viz. the increase in PM concentrations. That approach addresses the atmospheric transport of the emitted dust, and not its primary origin. In contrast, this paper examines the causes of the emission. The study is based on mass conservation of the dust deposited on the road surface. On the basis of this premise, estimates of emission rates were calculated from experimental data obtained in a road in a ceramic industrial area.

Cerebrotendinous xanthomatosis in Spain: clinical, prognostic, and genetic survey.

BACKGROUND AND PURPOSE: Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive disorder caused by mutations in the CYP27A1 gene resulting in sterol-27-hydroxylase deficiency. Current information about CTX is based mainly on case reports, with only few large series reported. Although perceived as a potentially treatable condition, efficacy of chenodeoxycholic acid plus statin therapy remains unclear. To perform a nationwide survey of confirmed cases, with a thorough analysis of genotype-phenotype data and prognostic factors. METHODS: Retrospective review of the clinical and epidemiological aspects and mutations of all the patients diagnosed since 1992 in the main reference centers for genetic testing of CTX in Spain. RESULTS: Twenty-five patients from 19 families were identified. An average delay of 19 years was observed between symptom onset and clinical diagnosis. Two main clinical subgroups were recognizable: a classic form (cerebellar and other supratentorial symptoms) and a spinal form (chronic myelopathy). Cholestanol levels did not correlate with clinical presentation, severity or response to therapy. Despite treatment, five patients died during follow-up, one to 4 years after diagnosis. Thirteen different mutations were identified, with a higher frequency of p.R395C in Northwestern Spain and p.R405W in Southern Spain. None of the mutations could be associated with a particular clinical feature combination or prognosis. CONCLUSIONS: This is the first nationwide extensive series of CTX reported in Spain. The higher number of cases in some areas suggests a possible founder effect. Spinal forms had a less severe prognosis. A delayed diagnosis could contribute to the lack of significant response to treatment.

A novel myelin protein zero (V136G) homozygous mutation causing late onset demyelinating polyneuropathy with brain white matter lesions.

Although less common than peripheral myelin protein 22 (PMP22) duplication, there are mutations in myelin protein zero (MPZ) responsible for Charcot-Marie-Tooth disease (CMT) with a number of different clinical profiles. We report here a novel MPZ homozygous mutation, with a peculiar pattern characterized by a late-onset demyelinating profile. In addition, the patient presented brain white matter lesions seemingly ascribable to the mutation.

[Usefulness of cholestanol levels in the diagnosis and follow-up of patients with cerebrotendinous xanthomatosis]. / Utilidad de los niveles de colestanol en el diagnóstico y seguimiento de los pacientes con xantomatosis cerebrotendinosa.

INTRODUCTION: cerebrotendinous xanthomatosis (CTX) is an autosomal recessive disease caused by a deficiency of mitochondrial enzyme sterol 27-hydrolylase. Such a deficiency results in a reduced production of chenodeoxycholic acid and in an increased formation of cholestanol. It is clinically characterized by cataracts, diarrhoea, xanthomas, premature arteriosclerosis and a number of progressive neurological symptoms. Although cholestanol levels are used for the diagnosis of CTX, their correlation with the clinical symptoms and their prognostic usefulness have not been assessed so far. METHODS: we reviewed 14 CTX patients diagnosed between 1995 and 2008 in two reference centres for the genetic diagnosis of this disorder, whose cholestanol levels had been recorded. We studied the main demographic, clinical and therapeutical data and their correlation with plasma cholestanol levels. RESULTS: the average cholestanol level at diagnosis was 105.8 µmol/l. These levels did not correlate with any neurological symptoms or with disability at diagnosis scored by the EDSS. After treatment, all patients achieved a significant reduction in plasma cholestanol levels (average reduction of 91 µmol/l in an average follow-up of 34 months), although only one patient remained clinically stable. CONCLUSIONS: high cholestanol levels are very useful for diagnosis of CTX but they do not have a prognostic value (they do not correlate with severity). Normalisation of cholestanol levels is not always associated with clinical stabilisation. However, follow-up of cholestanol levels can be useful for the dose adjustment.

Impact of fugitive emissions in ambient PM levels and composition: a case study in Southeast Spain.

The results of this study show the high impact that anthropogenic fugitive emissions of mineral dust have on air quality (levels of PM(10), PM(2.5) and some metals) in a region in SE Spain named L'Alacantí. This could be extensive to other areas of Europe with similar characteristics. Fugitive emissions, such as those arising from large public construction works, cement and ceramic manufacturing, mining, heavy industries, handling and transport of powdered raw materials and road dust, are very often left out of emission monitoring and inspections in Europe. The comparative study of daily PM(10) series in the area shows how the increase of annual average PM(10) concentrations over 40 microg/m(3) is due to extreme episodes occurring in 2006 and 2007, at a regional scale, given the simultaneous recording of PM episodes at distant monitoring sites. The annual average values of the PM(10) concentrations were close to or slightly higher than 40 microg/m(3) (limit value of Directive 2008/50/CE) during 2006-2007 (Alicante-University 39-41, Agost 40-42, Sant Vicent 42-46, Alicante-El Plà 40-42 microg/m(3)). The main PM(10) sources in the zone were identified with the assistance of the PMF receptor model. Six common factors were determined, mineral as a main source (37% at Agost and 32% at Sant Vicent), road traffic, secondary sulfate, petroleum coke, sea spray and industry. Mineralogical studies, with XRD and SEM-EDX techniques, support the hypothesis that the highest PM episodes are associated to fugitive emissions of mineral matter. Despite the fact that L'Alacantí region is a heavily industrialized area with two cement plants and a significant number of ceramic manufacturing plants, the fugitive emissions may have accounted for the exceedances of the PM limit values during these two years, part of them caused by the construction of a highway. These results may contribute to the interpretation of prior studies on source apportionment carried out in Southern Europe, with very high loads of anthropogenic dust in PM(10) and PM(2.5).

Familial Creutzfeldt-Jakob disease with E200K mutation presenting with neurosensorial hypoacusis.

Creutzfeldt-Jakob disease (CJD) is characterised by rapidly progressive dementia, myoclonus, ataxia, visual disturbances and motor dysfunction. Most of the cases are sporadic. Only 10% to 15% are familial, and the most frequent point mutation is E200K. A 53-year-old man presented with subacute progressive bilateral hypoacusis, with tinnitus in the left ear. During the following months, his hypoacusis worsened and he progressively developed bilateral stocking-type paresthaesia and gait instability. An audiometric examination showed bilateral neurosensorial hypoacusis and nerve conduction studies showed a mixed axonal polyneuropathy. A CT scan and MRI of the brain were normal and the electroencephalography (EEG) showed non-specific changes. He died of respiratory infection 10 months after onset of symptoms. Neuropathological examination showed neuronal loss, punctate, synaptic-like deposits of protease-resistant prionic protein (PrP(RES)) in the cerebral and cerebellar cortices and auditory nuclei. This is a rare case of sporadic CJD presenting with hearing loss.

[Frontotemporal lobar degeneration: a descriptive study of 42 patients]. / Degeneración lobular frontotemporal: estudio descriptivo de 42 pacientes.

INTRODUCTION: Frontotemporal lobar degeneration (FTLD) is considered to be the second cause of presenile dementia. In spite of the great interest it has generated over the last few years, few studies have been published in our country. METHODS: A descriptive retrospective study of 42 patients with FTLD evaluated in our unit during the period 1996-2006 was performed. RESULTS: Thirty one patients presented with frontal variant FTLD (FTD), eigth with non-fluent progressive aphasia and three with semantic dementia. Mean age at onset was 56 years, diagnostic delay 3.5 years and mean survival 6.8 years. 35% had a family history suggestive of dementia. In patients with FTD the clinical expression was a combination of behavioral and personality disorders together with language impairment. Magnetic resonance imaging showed frontal and/or temporal atrophy in 62% of cases and SPECT showed frontal and/or temporal hypoperfusion in 75%. The P301L tau mutation was detected in four patients (two of them siblings) and the A303AfsX57 progranulin mutation in one. Necropsy was performed in five patients, revealing FTLD with ubiquitininmunoreactive inclusions (FTLD-U) and motor neuron disease in two cases, FTLD-U with <> shaped intranuclear inclusions in the case with the progranulin mutation and FTLD tauopathy with predominance of 4R tau in the remaining two, both with the P301L mutation. CONCLUSIONS: Our results are similar to those of the great European series. FTLD must be suspected in presenile patients with prominent behavioral and/or language disorders. Neuroimaging supports the diagnosis in the majority of cases. The huge sociofamiliar impact of FTLD, presenile onset, high frequency of familial history of dementia and possibility of genetic study and counseling highlight its clinical relevance.

Cerebrotendinous xanthomatosis: neuropathological findings.

Cerebrotendinous xanthomatosis is an inherited autosomal recessive lipid storage disease caused by a 27-hydroxylase enzyme deficiency, characterised clinically by tendon xanthomas, premature cataracts, chronic diarrhoea and progressive neurologic dysfunction. The disease is very uncommon and there are very few pathological descriptions. We report a 52-year-old male who presented with a neuropsychiatric disorder and cognitive decline. Despite treatment the patient developed optic atrophy, parkinsonism and dementia and died. The autopsy revealed a nonspecific brain and cerebellar atrophy. Under microscopic examination, lipid crystal clefts, neuronal loss, demyelination, reactive astrocytosis and perivascular macrophages were found. These findings suggest the limited reversibility of the disease, and its poor prognosis, specially if treatment is not started early.

[Clinical variability and diagnostic controversies in CADASIL]. / Variabilidad clínica y controversias diagnósticas en el CADASIL.

Cardiovascular risk factors are present in 85% of patients with stroke. However, up to 6%-15% of patients have a stroke secondary to unusual reasons such as systemic diseases, coagulation disorders, etc., and, in some cases, no reason can be identified even after performing an extensive study. This usually happens in young people. In this regard, the diagnostic screening must consider hereditary causes of stroke. CADASIL, an autosomal dominant brain white matter angiopathy, is emerging as a not uncommon cause of stroke with diverse clinical manifestations. Its clinical diagnosis is controversial because of the diverse role of the brain imaging study, the biopsy of the vessels of skin or other tissues and the DNA study.

[Humidifier fever: and unusual variant of hypersensitivity pneumonitis]. / Fiebre de los humidificadores: una rara variante de neumonitis por hipersensibilidad.

A case of a patient suffering three episodes consistent in fever, lung infiltrates, lymphocitosis in bronchoalveolar lavage and non-caseificant granulomata in transbronchial biopsy is reported.A relationship between exposition to the air conditioner in the office and the clinical picture was stablished, and the patient was finally diagnosed from humidifiers fever. We enfatize the manifestations of this uncommon disease, probably infradiagnosed, and the patogenic mechanisms are reviewed.

[Young's syndrome in the adult age: home treatment with a mechanical device of intrapulmonary percusive ventilation]. / Síndrome de Young en la edad adulta: tratamiento domiciliario mediante un dispositivo mecánico de percusión intrapulmonar.

We studied a man with bronchiectasis, chronic sinopulmonary infections and obstructive azoospermia diagnosed of Young's syndrome in the adult age. The patient was treated at home by a mechanical system of respiratory care based in intrapulmonary percussive ventilation (Percussionaire) reaching a significant clinical and functional improvement. Our case enhanced the importance to make a proper history of fertility in patients with bronchiectasis in order to establish the diagnostic. We review different methods of respiratory mechanical assistance in patients with bronchiectasis.

Study of plasma antioxidant status in Alzheimer's disease.

To examine the plasma antioxidant status of Alzheimer's disease (AD) patients and to evaluate the influence of apolipoprotein E (APOE) genotype. There are reasons to suspect involvement of the free hydroxyl radical in the pathogenesis of AD. In contrast, studies in plasma of AD patients for the evaluation of levels of biomarkers of oxidation are controversial. Twenty AD patients diagnosed using the National Institute for Neurological Disorders/Alzheimer's Disease and Related Disorders (NINDS/ADRDA) criteria and 22 controls chosen amongst different subjects without cognitive damage. All the subjects--both AD patients and controls--were stratified by their APOE genotype (3/3, 3/4 or 4/4), which was determined by PCR. Plasma total antioxidant capacity (TAC) was determined using two complementary procedures: FRAP, which measures the ferric reduction capacity, and ABTS, which measures the radical scavenging capacity. In addition, 2-amino-adipic semialdehyde (2-AAS), a biomarker of protein oxidation, was evaluated. No significant difference was observed between the AD and control groups regarding plasma TAC. When the subjects were classified by their APOE genotype, significant differences were found in the APOE 4/4 group in the TCA determined by the FRAP method. Subjects with APOE genotype 4/4, which is the group with higher incidence in AD, showed lower antioxidant capacity of plasma. It is the first time that antioxidant capacity in plasma is evaluated in AD patients characterized by their APOE genotypes.