The Interaction of Pesticides with Humin Fractions and Their Potential Impact on Non-Extractable Residue Formation.

The constant influx of pesticides into soils is a key environmental issue in terms of their potential retention in the soil, thus reducing their negative impact on the environment. Soil organic matter (SOM) is an important factor influencing the environmental fate of these substances. Therefore, the aim of this research was to assess the chemical behavior of pesticides (flufenacet, pendimethalin, α-cypermethrin, metazachlor, acetamiprid) toward stable soil humin fractions (HNs) as a main factor affecting the formation of non-extractable residues of agrochemicals in soil. This research was conducted as a batch experiment according to OECD Guideline 106. For this purpose, HNs were isolated from eight soils with different physicochemical properties (clay content = 16-47%, pHKCl = 5.6-7.7, TOC = 13.3-49.7 g·kg-1, TN = 1.06-2.90 g·kg-1, TOC/TN = 11.4-13.7) to reflect the various processes of their formation. The extraction was carried out through the sequential separation of humic acids with 0.1 M NaOH, and then the digestion of the remaining mineral fraction with 10% HF/HCl. The pesticide concentrations were detected using GC-MS/MS. The pesticides were characterized based on the different sorption rates to HNs, according to the overall trend: metazachlor (95% of absorbed compound) > acetamiprid (94% of absorbed compound) > cypermethrin (63% of partitioning compound) > flufenacet (39% of partitioning compound) > pendimethalin (28% of partitioning compound). Cypermethrin and metazachlor exhibited the highest saturation dynamic, while the other agrochemicals were much more slowly attracted by the HNs. The obtained sorption kinetic data were congruous to the pseudo-first-order and pseudo-second-order models related to the surface adsorption and interparticle diffusion isotherm. The conducted research showed that the processes of pesticide sorption, apart from physicochemical phenomena, are also affected by the properties of the pollutants themselves (polarity, KOC) and the soil properties (SOM content, clay content, and pHKCl).

Retropharyngeal Ectopic Thymus in a Pediatric Patient With 22q11.2 Deletion Syndrome.

The thymus gland plays a crucial role in the maturation process of lymphocyte T cells. Developmental disorders of this organ might be caused by genetic diseases, such as the 22q11.2 deletion and DiGeorge syndrome. Other manifestations of this condition are heart defects, a reduced number of T cells, hypocalcemia, and facial dysmorphia. A 13-year-old boy with 22q11 deletion syndrome presented with paresis and paresthesia of the right upper extremity. Magnetic resonance imaging (MRI) revealed a solid mass in the retropharyngeal and prevertebral areas. The lesion was excised and, upon histopathological examination, turned out to be ectopic thymic tissue. A follow-up examination showed no recurrence of the lesion. The ectopic thymus is a rare pathology, especially in 22q11 deletion syndrome patients. In general, thymic tissue can be found anywhere along its normal path of descent. In this case, however, its location cannot be explained solely by its embryological origin, as at no point should the thymus or its histological predecessor be located in the retropharyngeal area. As such, this finding challenges our current understanding of thymic embryological genesis.

Optimized isolation method of humin fraction from mineral soil material.

Humic substances, including humin fraction, play a key role in the fate of organic and inorganic xenobiotics contaminating the environment. Humin is an important fraction of humic substances, which has been the least studied to date. This is due to the difficulties connected with its isolation that pose a number of methodological problems. Methods of humin fraction isolation can be divided into following main groups: (1) digestion of mineral soil components with HF/HCl followed by alkali extraction of HA and FA; (2) alkali extraction of HA and FA followed by extraction of humin by different organic solvents; and (3) alkali extraction of HA and FA followed by HF/HCl digestion of mineral soil components. Nevertheless, each of these methods has different limitations. We described in detail a useful procedure of humin isolation, in which this fraction was not extracted, but isolated from the soil by removing its soluble organic and mineral components. A modified method of HA and FA extraction with 0.1 M NaOH, according to the International Humic Substances Society, was used in the first step. Then, the mineral components in the residue were digested with the 10% HF/HCl. Unlike the procedures oriented to increase the concentration of organic matter, samples were treated several times with the HF/HCl mixture until the mineral fraction was almost completely digested. The main assumption of the method modification was to obtain the highest yield with the lowest possible ash content, but without affecting humin chemical structure. The results showed that the proposed procedure is characterized by a high efficiency and recovery and, therefore, it can be used to isolate high amounts of humin from soil.

Epilepsy and cognitive deterioration as postoperative complications of the arachnoid cyst fenestration: Case report.

Objective: With the aim of contributing to the discussion on treatment of patients with arachnoid cysts (AC) and their neuropsychological functioning, we present the case of a patient who has undergone surgery of AC located in the left Sylvian fissure. Case description: The patient had no cognitive deficits and no seizures before the cyst's fenestration. After the procedure, however, occurrences of seizures have been observed. Along with the concomitant epileptic seizures, aphasia and serious memory problems also developed. The initial pharmacological treatment of the seizures brought about unsatisfactory results. The treatment was therefore modified a number of times and ultimately, seizures were brought under control to some extent. Despite the varied efforts at neuropsychological rehabilitation, cognitive impairment was still persistent up to a year after the surgery. Conclusions: 1) While referring patients with AC for surgery, one should always consider both the positive outcomes and the unintended and deleterious consequences. A cyst fenestration could in some cases lead to epilepsy and cause neuropsychological symptoms such as anomic aphasia and cognitive deterioration with memory function impairment. 2) Neurological patients, especially the ones qualified for surgery, should always undergo neuropsychological examination. The lack of data from presurgical neuropsychological examination may impact further treatment of neurosurgical patients.

The health-related quality of life in children with arachnoid cysts. Clinical predictors and parent-child perspectives.

BACKGROUND: In clinical practice, arachnoid cysts (AC) are usually detected by coincidence and are frequently considered as clinically mute. Even though an AC does not usually result in serious symptoms, the diagnosis itself can have a significant impact on the patients and their families, especially in terms of psychological functioning and quality of life. METHODS: Participants were 22 children diagnosed with AC and their parents. We analyzed patients' medical records and assessed them using the Stanford Binet Intelligence Scale, fifth edition. Additionally, both children and parents filled in the Polish version of the PedsQL™ 4.0 generic core module. RESULTS: The Health-RelatedQuality of Life (HRQOL) is not related to objective predictors such as radiological predictors and SB 5 results. However, there is a correlation between the HRQOL, and symptoms given in the interview. Secondly, parents assess the HRQOL of their children worse compared to the children's own ratings. Lastly, children with AC assess the HRQOL in a way that is similar to the assessment done by healthy children in the original study describing PedsQL™, whereas parents assess children's HRQOL in a way rather similar to the assessment done by parents of patients. CONCLUSIONS: The results show the impact of the disease's image and understanding on the HRQOL. Basing on our results we conclude the important role of psychological support for patients with AC. We furthermore conclude that parents of children with AC assess the HRQOL of children worse compared to the children's own ratings.

Are arachnoid cysts actually clinically mute in relation to neuropsychological symptoms? Cognitive functioning in children with AC of middle and cranial fossa.

Aiming at being part of the discussion about the cognitive functioning of patients with arachnoid cysts (AC) and the value of neuropsychological testing in these patients, we present our study in which we investigated the cognitive functioning of 32 children with ACs of the middle cranial fossa. We compared the Stanford Binet 5 (SB 5) results obtained by the patients with the population mean values and analysed the relation between the patients' clinical details and the results of SB 5. The main conclusions of this research are: (1) In SB 5 tasks, the tested group performed worse than the population mean, which could be related to AC of the middle cranial fossa. Deficits concern especially visuospatial reasoning, quantitative reasoning, and knowledge. The obtained results indicate the coexistence of cognitive impairment and AC of the middle cranial fossa. (2) In patients with AC, neuroimaging information has only limited predictive ability regarding cognitive syndromes. (3) The complaints reported in the interview are not necessarily objectively reflected in the clinical assessment. Neuropsychological assessment should be part of the management of all patients with AC. (4) Cognitive deficits in patients with AC may become more pronounced with age. Accordingly, increasing school difficulties in these patients should be expected. In light of the above, there is a clear indication of the need for neuropsychological support and support in school functioning for patients with AC. (5) Neuropsychological control in patients with AC is crucial not only with regard to treatment decisions but primarily for monitoring school performance and providing these patients with adequate neuropsychological and psychological support.

Cognitive Impairment in Children with Arachnoid Cyst of Sylvian Fissure: Does it Justify the Neurosurgical Treatment?

This report discusses the relationship between arachnoid cysts (ACs) and cognitive deficits, and we ask if cognitive impairments could justify neurosurgical treatment. In clinical practice, only AC patients with symptoms of intracranial hypertension or focal neurological deficits are referred to surgery. Occasionally, one might assume that nonspecific problems such as impairment of learning, speech, or cognitive functions are caused by an AC and can be improved by surgery. We describe three patients, in which surgery was indicated on the basis of clinical symptoms such as headaches and the size of the cysts. A neuropsychological examination before AC surgery revealed reduced cognitive potential, and the same examination repeated after surgery showed improvement. We have not found any other reason for this change, except for the decompression of the AC.

Comparison of three derivatization ways in the separation of phenol and hydroquinone from water samples.

Hydroquinone and phenol were analysed in aqueous alkaline model samples using chromatographic techniques. The compounds were isolated by solid-phase extraction and determined quantitatively by capillary gas chromatography after derivatization. The effectivity of derivatization was tested in three phases of sample handling: (i) before extraction; (ii) in the extraction bed; and (iii) during elution.