Formaldehyde Solution Research Articles

Polypeptide and copper oxide nanocomposite hydrogel for toxicity elimination of wastewater

In this experimental study, a novel bionanocomposite of gelatin as a polypeptide hydrogel consisting of copper (II) oxide nanomaterial (GL–CuO) was prepared. After dispersing the synthesized CuO nanoparticles (NPs) within the GL aqueous solution, they were cross-linked by the addition of a formaldehyde solution. The resulting GL–CuO nanocomposite hydrogels were further characterized by FESEM, EDX, XRD, XPS, and FTIR. The FESEM micrographs confirmed the uniform distribution of CuO NPs in the hydrogel matrix, with dimensions ranging from 60 to 80 nm. The XRD patterns confirmed the presence of the monoclinic crystalline form of CuO NPs embedded in the GL hydrogel. The GL–CuO catalyst was tested in the reduction of two azo dyes. All the reactions were carried out in the presence of a strong reducing agent, NaBH4, with the catalyst demonstrating high activities toward methyl orange and congo red with reaction rate constants of 9.91 × 10−1 min−1 and 5.8 × 10−1 min−1, respectively. The reduction of these dyes was followed by UV–visible spectroscopy that confirmed complete reduction of the dye.

Synthesis, computational and biological activity of heteroatomic compounds based on phenylthiourea and acetophenone

The presented article is devoted to a promising direction of organic chemistry - the synthesis of new sulfur- and nitrogen-containing thiourea and acetophenone derivatives that have physiological properties. So at first time on the base of phenylthiourea, acetylacetone and 37% water solution of formaldehyde (formaline) in the presence of trifluoracetic acid has been elaborated new effective synthesic method of 1-(6-Methyl-3-phenyl-2-sulfanylidene-1,2,3,4-tetrahydropyrimidin-5-yl)ethanone. Also, according to the reaction of thiylation of acetophenone and some of its p-substituted derivatives Synthesis of 2,2’-((1-phenylethane-1,1-diyl)bis(sulfanediyl))diacetic acid were obtained by us. A direct amidation reaction of Synthesis of 2,2’-((1-phenylethane-1,1-diyl)bis(sulfanediyl))diacetic acid with primary amines was conducted. The structure of the new compounds was interpreted by NMR spectra and X-ray structure analysis. As a result of studies, it was found that the greatest biological activity that can be useful in creating drugs is compound 1-(6-Methyl-3-phenyl-2-sulfanylidene-1,2,3,4-tetrahydropyrimidin-5-yl)ethanone. This compound is characterized by antioxidant effect significant effect on the functioning of biological membranes, and in low concentrations (below 7.5 mg/l) it stabilizes the membranes with an erythrocyte. The effect of an increase in the membrane potential of mitochondria was discovered, probably associated with the ability to bind to carrier proteins. In addition, when virtually predicting the spectrum of biological activity, a number of properties are shown that have promise when creating new drugs.

Cardiovascular Effects of Polychlorinated Biphenyls and Their Major Metabolites.

Background:Xenobiotic metabolism is complex, and accounting for bioactivation and detoxification processes of chemicals remains among the most challenging aspects for decision making with in vitro new approach methods data.Objectives:Considering the physiological relevance of human organotypic culture models and their utility for high-throughput screening, we hypothesized that multidimensional chemical-biological profiling of chemicals and their major metabolites is a sensible alternative for the toxicological characterization of parent molecules vs. metabolites in vitro.Methods:In this study, we tested 25 polychlorinated biphenyls (PCBs) [PCB 3, 11, 52, 126, 136, and 153 and their relevant metabolites (hydroxylated, methoxylated, sulfated, and quinone)] in concentration–response () for effects in human induced pluripotent stem cell (iPSC)-derived cardiomyocytes (CMs) and endothelial cells (ECs) (iPSC-derived and HUVECs). Functional phenotypic end points included effects on beating parameters and intracellular flux in CMs and inhibition of tubulogenesis in ECs. High-content imaging was used to evaluate cytotoxicity, mitochondrial integrity, and oxidative stress.Results:Data integration of a total of 19 physicochemical descriptors and 36 in vitro phenotypes revealed that chlorination status and metabolite class are strong predictors of the in vitro cardiovascular effects of PCBs. Oxidation of PCBs, especially to di-hydroxylated and quinone metabolites, was associated with the most pronounced effects, whereas sulfation and methoxylation of PCBs resulted in diminished bioactivity.Discussion:Risk characterization analysis showed that although in vitro derived effective concentrations exceeded the levels measured in the general population, risks cannot be ruled out due to the potential for population variability in susceptibility and the need to fill data gaps using read-across approaches. This study demonstrated a strategy for how in vitro data can be used to characterize human health risks from PCBs and their metabolites. https://doi.org/10.1289/EHP7030

Histological Examination of Rat Heart Tissue with Chronic Diabetes

Diabetes mellitus causes structural and functional impairment of the system in the organism by affecting various organs and structures. In this study, we aimed to examine the changes in female rat heart tissue histologically by creating experimental diabetes. 16 female adult rats were used in the study. Rats were randomly divided into two groups as control and 3- month diabetes. The diabetes group was formed from subjects with blood glucose levels above 250mg/dl 72 hours after 40 mg / kg streptozotocin administration. At the end of the experiment, the heart tissues of the subjects were removed and taken into formaldehyde solution. To examine the histological structure, hematoxylin-eosin (H-E) and immunohistochemically neuronal nitric oxide syntahase (nNOS) and inducible nitric oxide syntahase (iNOS) were stained. Heart tissue sections belonging to the control group had histologically normal appearance. In the diabetes group heart tissue sections, vacuolization in some cells and eosinophilic increase in the cytoplasm of some cells were observed. The nNOS and iNOS immunreactivity was observed to be decreased in the diabetes group compared to the control group, but the decrease was not statistically significant. As a chronic disease, DM causes histological damage to the heart tissue. The resulting damage causes a decrease in nNOS and iNOS expression. It is important to maintain NOS enzyme levels in order to protect tissue from the harmful effects of diabetes and ensure normal physiological conditions.

Нова знахідка Vaucheria aversa Hass. (Ochrophyta, Xanthophyceae) в Україні

Vaucheria aversa (Xanthophyta) was recorded for the first time in Ukraine in Sula River, Hydrological Reserve «Artopolot», Poltava Region. It was found in benthos in spring (May 2020) in silty-sandy soil in shallow water. The material was collected and processed according to a common methodology. Sterile samples before the appearance of the gametengians were kept in natural water in petri dishes in well-lit places. This method of «coarse culture», in most cases, allowed to get gametangia within two weeks. The species identification was done with fertile filaments only. 4% formaldehyde solution was used for material fixation. Taxonomic identification of samples was done using a comparative and morphological methods, which includes analysis of morphological variability and verification of the consistency of the studied material with the diagnosis. Thalli of V. aversa are direct, branched, bisexual, 80–90 μm wide. Antheridia are cylindrical, tubular shape, pressed to the filament or slightly raised above it, 119–130 × 41–43 μm. Oogonia erect, sessile, ovoid to subspherical, sometimes placed in pairs, with a curved beak at the front, 190–230 × 140–163 μm. According to morphological characteristics this species is similar to another one from section Tubligerae Walz – V. fontinalis (Linnaeus) T.A. Christensen. Their distinctive and common features are as follows. Filaments of V. fontinalis are narrower (up to 75 μm) than V. aversa (up to 131 μm). Both species are characterized by oogonia grouped together in a row. Antheridia present in quantity 1 or 2 on both sides of oogonia. But the species are very different in size and shape of oogonia: in V. aversa they are sessile, located one at a time or less often two, extended near the base, sharply narrowed at the apex. The beak is directed straight or obliquely up, bent to the side of the oogonia body. In V. fontinalis oogonia are placed in one row, most often in the amount of 1-6, the beak tapers gradually. Anteridia are cylindrical, on short pedicel. V. aversa grew as a part of polyspecies complex of green algae together with representatives of such genera as Cladophora Kützing, Spirogyra Link and Mougeotia C. Agardh. V. aversa is widely distributed in continental water bodies of Europe, Asia and North America, Australia and New Zealand, but is firstly recorded in Ukraine.

Anatomical study of the pial arterial network in human spinal cords.

Multiple collaterals originate from three main longitudinal vessels to perfuse the human spinal cord. Only a few classic studies published in the last century have investigated these collaterals. The current work proposes a possible classification of these vessels and analyzes their relative abundance along spinal cord segments. Human spinal cords (n = 30) from male and female cadavers were injected with colored latex through the vertebral, ascending cervical, costocervical trunk and segmental arteries and then fixed in formaldehyde solution. Afterwards, spinal vessels were dissected and the relative abundances of each type of collateral were quantified and compared between different spinal cord segments. Collaterals of the anterior longitudinal pathway can be classified as central arteries and arteries for the anterior and lateral columns. Collaterals for the anterior column can be classified into two types: anteromedial and anterolateral. Arteries for the lateral column can be classified, according to their relationship with the dentate ligament, as either preligamentous or post-ligamentous. The collaterals of posterior longitudinal pathways can be divided between those for the posterior and those for the lateral column. In turn, the arteries for the posterior column can be classified into three types: median posterior, posteromedial and posterolateral. The collaterals for the lateral column were also classified as either pre- or post-ligamentous. The relative abundance of the various types of collateral and anastomoses between longitudinal pathways was inhomogeneous along the spinal cord, with several statistically significant differences observed between spinal segments.

ФІТОПАРАЗИТИЧНІ НЕМАТОДИ ПРИРОДНИХ ЕКОСИСТЕМ ЛІВОБЕРЕЖНОГО ПОЛІССЯ (У МЕЖАХ ЧЕРНІГІВСЬКОЇ ОБЛАСТІ)

The species composition, frequency of occurrence, and the abundance of phytohelminths in communities of soil nematodes in natural ecosystems of the Left-Bank Polissia (Chernihiv region) were studied. Samples were collected throughout 2011-2016 in forest and meadow ecosystems on the territory of Chernihivskyi, Horodnianskyi, Kozeletskyi, Koropskyi, Menskyi, Ripkynskyi, Sosnytskyi, Semenivskyi, Shchorskyi and Novhorod-Siverskyi districts.
 Nematodes were extracted by a modified Baermann’s method from the 20-g sample. The exposition time was 48 h. Extracted nematodes were fixed in the triethanolamine–formalin (TAF, 2 % triethanolamine, 7 % formaldehyde solution, 91% water), and mounted on the temporary hydroglyceric slides. Nematode abundance was expressed as specimens per 100 g of dry soil.
 Seventeen species from three orders, ten families and fifteen genera were found. Eleven species (64.7 % of the species composition) belonged to the order of Tylenchida, four (23.5 %) – Triplonchida, two (11.8 %) – Dorylaimida.
 Eleven species (Gracilacus audriellus, Paratylenchus nanus, Tylenchorhynchus dubius, Helicotylenchus dihystera, Macroposthonia annulata, Diphtherophora communis, Trichodorus primitivus, Paratrichodorus teres, Paratrichodorus pachydermus, Longidorus elongatus, Xiphinema index) are ectoparasites, three species (Ditylenchus dipsaci, Pratylenchus pratensis, Hirschmaniella gracilis) – endoparasites, and three species (Hemicycliophora sp., Heterodera sp. 1, Heterodera sp. 2) – semiendoparasites.
 Phytohelminths in communities of soil nematodes in forest ecosystems ranged from 9.4 to 26.3 %. But in meadow ecosystems of the Mezin National Nature Park it was a dominant group (proportion in the community 47%). 
 The most frequent species were G. audriellus, H. dihystera and T. dubius which occurred in 33.3 %, 33.3 % and 28.3 % of samples respectively. P. nanus, D. dipsaci, P. pratensis та D. communis – had frequency of occurrence 15 – 20%. Ten species of phytohelminths were found in 1–4 ecosystems (1.7–6.7%).
 G. audriellus and H. dihystera were abundant (124 and 56 specimens per 100 g of soil respectively).

Modeling vapour-liquid phase equilibrium for the aqueous solutions of formaldehyde and electrolyte

Modeling of vapor-liquid equilibrium for the aqueous solutions of formaldehyde and electrolyte is required for the extractive distillation of formaldehyde-containing multicomponent mixtures using salt as entrainers. Here a revised physicochemical model, which integrates the advantages of the physicochemical model for the vapor-liquid and the chemical equilibria in aqueous formaldehyde solution and the LIFAC model for the phase behavior in mixed-solvent electrolyte systems, has been proposed. The new vapor-liquid equilibrium data in (HCHO–H2O–salt) were systematically measured and utilized to determine newly-introduced model parameters. Comparisons of model calculated and experimental measured values proved that the model presented here provides a reliable method for correlating the vapor-liquid equilibria data in (HCHO–H2O–salt) system. Furthermore, the model established in this work was used to study salts effect on vapor-liquid equilibria. Both the model calculations and the VLE experiments uncover that Zn(NO3)2 is the most promising among all of the entrainers investigated.

Expression of PCNA, MMP-9, p53, Bax and Bcl-2 in canine transmissible venereal tumors

In this study, we aimed to evaluate the proliferative, metastatic and apoptotic capacities of TVT cases, which are in various phases of development, by using immunohistochemical markers. The material of this study consisted of twelve female and six male dogs diagnosed with TVT brought to our department between 2007 and 2020 years. Diff-quick staining was applied to the smear taken from tumoral masses for cytological examinations. Tumoral tissues from dogs were fixed in a 10% neutral buffered formaldehyde solution. After routine tissue procedures Hematoxylin & Eosin stain was applied to the sections. Tissue sections were investigated under a light microscope and photographed. Immunohistochemical staining was performed on the tissues using the avidin-biotin immune peroxidase complex method. As a result of macroscopic, cytological and histopathological examinations, TVT positive cases were divided into three according to their developmental stages. While the expression of PCNA, MMP-9, mutant p53 and Bcl-2 increased significantly in progressive cases compared to regressive and stable cases, Bax expression increased significantly in regressive cases compared to progressive and stable cases. In conclusion, we thought that the mentioned markers are very useful for understanding the prognosis of TVT, the tumor aggressiveness and the survival of the malignant cells.

Determination of Glutathione and Cysteine in Human Breast Milk by High-Performance Liquid Chromatography with Chemiluminescence Detection for Evaluating the Oxidative Stress and Exposure to Heavy Metals of Lactating Women

Exposure to heavy metals may affect a vast array of biochemical and nutritional processes in the human body. The toxic manifestations of these metals are caused primarily due to the imbalance between pro-oxidant and antioxidant homeostasis which is termed as oxidative stress. A high-performance liquid chromatography–chemiluminescence (HPLC-CL) method was developed for the simultaneous determination of two antioxidants, glutathione and cysteine, in human breast milk. The HPLC system included a C18 analytical column with a mobile phase composed of 1.0% methanol. The aminothiols were eluted from the C18 column, mixed with formaldehyde and potassium permanganate solutions, and subsequently monitored by a chemiluminescence detector. The new method was validated by monitoring glutathione and cysteine in human breast milk of volunteers from the Gusu and Industrial Districts of Suzhou, China. Four heavy metals in atmospheric particulate matter collected from the two districts were also determined by inductively coupled plasma–mass spectrometry (ICP-MS). The results demonstrated that the concentrations of cysteine and glutathione were significantly (p < 0.05) lower in human breast milk from the subjects living in the Gusu region of Suzhou, Jiangsu Province, China compared to an industrial district. These results were inversely correlated with the concentration levels of the toxic metals in collected atmospheric particulate matter. The decrease in the glutathione and cysteine concentrations in human breast milk appeared to be due to oxidative stress in the breast-feeding mothers.

Palladium-polypyrrole composites as prospective catalysts for formaldehyde electrooxidation in alkaline solutions

Palladium-polypyrrole (Pd-PPy) composites synthesized via one-step and one-pot redox procedure have been tested as electrocatalysts for formaldehyde oxidation in aqueous solution under both inert and oxygen atmospheres. It has clearly been shown that inert electrode coated by the Pd-PPy composites demonstrates a high catalytic activity. Electrochemical response of Pd-PPy modified electrodes depends on the anodic potential range, pH and concentration of formaldehyde in solution as well as on the presence of oxygen in reaction atmosphere. It has been found that Pd-PPy composites are prospective materials for amperometric detection of formaldehyde in aqueous solution, even under oxygen atmosphere, as well as in the presence of methanol or/and formate-anions.

Investigation of optimal sample preparation conditions with potassium triiodide and optimal imaging settings for microfocus computed tomography of excised cat hearts.

To determine optimal sample preparation conditions with potassium triiodide (I2KI) and optimal imaging settings for microfocus CT (micro-CT) of excised cat hearts. 7 excised hearts (weight range, 10 to 17.6 g) obtained from healthy adult cats after euthanasia by IV injection of pentobarbital sodium. Following excision, the hearts were preserved in 10% formaldehyde solution. Six hearts were immersed in 1.25% I2KI solution (n = 3) or 2.5% I2KI solution (3) for a 12-day period. Micro-CT images were acquired at time 0 (prior to iodination) then approximately every 24 and 48 hours thereafter to determine optimal sample preparation conditions (ie, immersion time and concentration of I2KI solution). Identified optimal conditions were then used to prepare the seventh heart for imaging; changes in voltage, current, exposure time, and gain on image quality were evaluated to determine optimal settings (ie, maximal signal-to-noise and contrast-to-noise ratios). Images were obtained at a voxel resolution of 30 μm. A detailed morphological assessment of the main cardiac structures of the seventh heart was then performed. Immersion in 2.5% I2KI solution for 48 hours was optimal for sample preparation. The optimal imaging conditions included a tube voltage of 100 kV, current of 150 μA, and exposure time of 354 milliseconds; scan duration was 12 minutes. Results provided an optimal micro-CT imaging protocol for excised cat hearts prepared with I2KI solution that could serve as a basis for future studies of micro-CT for high resolution 3-D imaging of cat hearts.

Modification of Starch from Taro Tubers with Hydrolysis Acid As the Adhesive

The use of Starch from Taro tubers as an adhesive raw material is done by hydrolyzing talc of Taro Tuber into dextrin using Chloride Acid (HCl) as the catalyst. The variables involved in this research are temperature and hydrolysis time whence the variations of temperature are 80°C, 100°C, 120°C, and 140°C also for the duration of hydrolysis time are 10, 20 and 30 minutes. The variations of temperature and time can affect the nature of dextrin produced. The analysis parameters include swelling power, solubility, dextrose equivalent (DE) and water content. The hydrolysis of taro tuber starch is then added with sodium bicarbonate (NaHCO3) and formaldehyde solution (CH2O). The mixture is added with some water and heated to a temperature of 60°C to form a homogeneous mixture. After the Dextrin Glue is formed, the process is continued by analyzing the adhesive power of the synthesized gluten. From the research’s outcome, knowing that the optimum condition of adhesive was at 80°C and 30 min of hydrolysis time also the analysis number of swelling power is 2.27, along with 1.7% solubility, dextrose equivalent 3,523%, moisture content 14% and the adhesion 283,84 N/cm2.

Protocols for Reducing Autofluorescence and Improving Fluorescent Nuclear Staining in Mouse Testis

Previously, we had encountered significant autofluorescence (AF) in Leydig cells in the testis. Leydig autofluorescence often represents a barrier to effectively analyzing and depicting the expression of proteins by testicular Sertoli cells. Biological AF is an intrinsic property of cells and tissues, and intrinsic autofluorescence of some tissues can serve as a useful diagnostic indicator in certain disease situations. However, it is often an obstacle to immunofluorescence‐based analyses by masking and interfering with specific fluorescent signals. Hence, the need to reduce tissue AF is imperative for a successful visualization of co‐localizing proteins. Therefore, we sought to utilize the fat‐soluble diazo dye Sudan Black B (SBB) to reduce undesirable autofluorescence in our samples. Following treatment of the testis tissue sections with Sudan Black B for 10–15 min, the intrinsic fluorescence was significantly masked, allowing specific staining of Sertoli and Leydig cells with antibodies against SOX9 and DDX4. Additionally, we sought to use an alternative fluorescent nuclear stain, as 4′,6‐diamidino‐2‐phenylindole (DAPI) produces insufficient labeling in the nuclear of testis cells fixed with Bouin’s solution, which is used more commonly than formaldehyde solutions in testis research. As a result, we have developed protocols to significantly 1) treat tissue with SBB to reduce autofluorescence, and 2) improve fluorescent nuclear staining in mouse testis, without changing fixative solutions. These protocols can be used separately or together and can be altered to fit optimal experimental parameters. The method developed in this study will improve the visualization of multiple AF signals.

Microbial Growth on Soft Embalmed Cadavers Over Time

Objectives At their inception, cadaveric anatomical studies were performed without embalming of any kind. Over time, physicians correlated rates of infection and death with cadaveric exposure and cross contamination. Formaldehyde solutions are now the most familiar and widely used embalming formulas. While formaldehyde embalming provides preservation and disinfection, it also makes cadavers stiff, unpliable and a less efficacious option for surgical training. Fresh cadavers can provide an alternative, however without some sort of preservation these cadavers quickly putrefy and pose an infectious risk. To address this problem, soft embalming techniques have been developed for anatomical and surgical studies. As soft embalming techniques have grown in popularity, the solutions and methods have diversified, and a wide variety of soft embalming solutions are being used. Soft embalmed cadavers are often used over extended periods of time in educational environments making them potential sites for microbial colonization and infectious exposure. While there are many studies evaluating the educational utility of soft embalmed cadavers, there are very few studies monitoring their long-term antimicrobial efficacy. The objectives of this study are twofold: 1. Examine the long-term antimicrobial capacity of a Surgical Reality Fluid, one of the many soft embalming solutions available. 1. Quantify and identify any microorganisms found in order to evaluate for potential infectious risk and possible need for more thorough safety measures when working with such soft embalmed cadavers. Methods Prior to embalming, a sterile swab was used to sample the oral, nasal, rectal, inguinal, pedal, and axillary regions of 4 donated bodies. The samples were then plated on the following agars: blood, EMB, CNA columbia, nutrient, and sabouraud. The agar plates were then incubated at 37 C for 4–7 days. All unique colonies were gram stained in an attempt to identify each colony. PCR was used to quantify bacterial load. The first sampling was completed preembalming and served as a baseline for each cadaver. After embalming, repeat sampling took place every 2 months for 6 months. Results Growth was identified prior to embalming. As data was continually collected, cadavers were monitored for the presence of persisting bacteria or re-colonization over time. Any bacteria present was compared against what was present prior to embalming, what would be expected with a typical non-embalmed necrobiome, and possible cross contamination during educational activities. Conclusions This is the first study to monitor bacterial growth over time on cadavers embalmed with Surgical Reality Fluid. The conclusions of this study serve to elucidate if further safety measures or regulation of embalming techniques are needed for soft embalmed cadavers in an educational setting. Support or Funding Information None

Vascularization of the Alouatta belzebul brain base

ABSTRACT: We studied the arterial circle in the brain of five specimens of the Alouatta belzebul primate. The material had the arterial system perfused (water at 40°C), injected with stained latex (Neoprene 650), fixed in aqueous formaldehyde solution (10%) and dissected for vessel verification. The arterial circle of this primate is composed of two vascular systems: the vertebra-basilar and the carotid ones, which anastomose to close the arterial circuit. In the caudal portion of the arterial circle, there are the vertebral arteries and their branches: the rostral spinal artery and the caudal inferior cerebellar artery. The anastomosis of the vertebral arteries gives rise to the basilar artery. It presented an anatomical variation at the beginning of its path, forming a double basilar artery, called arterial island. In its course, it emitted branches giving rise to the rostral inferior cerebellar artery, the pontine arteries, the rostral cerebellar arteries, the satellite rostral cerebellar arteries and its terminal branch, the caudal cerebral artery, which presented itself in two segments: the pre-communicating one and post-communicating, joining the internal carotid artery and originating the caudal communicating artery. This group of arteries and anastomoses enclose the caudal portion of the arterial circle. From the right and left internal carotid arteries begins the rostral portion of the arterial circle, which consists of the right and left rostral cerebral arteries and the right and left middle cerebral arteries. The rostral cerebral arteries anastomose into a single trunk, giving rise to the interhemispheric artery, and in A. belzebul and Sapajus libidinosus, the rostral communicating artery is absent. The interhemispheric artery goes to the midbrain region and the corpus callosum knee divides into pericalous artery and callosarginal artery, which will supply the pre and post-central regions of the cerebral hemispheres of this species, as well as other non-human and human primates. It is noted that in the first part of the left rostral cerebral artery, there is a direct inosculation between the recurrent branch of the rostral cerebral artery and left middle cerebral artery to supply the entorhinal region. This fact also occurs in Pongo spp. The middle cerebral artery travels along the lateral sulcus where it emits several superficial branches to irrigate the superior and inferior lateral cortical regions of the frontal, parietal and temporal lobes. It is not part of the arterial circle but is the terminal branch of the internal carotid artery. A. belzebul can be considered to depend on two sources of supply to the brain: the vertebra-basilar and carotid systems, contributing to the intervention of veterinarians during clinical and surgical procedures in other primates, as well as the preservation of wild animals.

Gas-Particle Partitioning of Formaldehyde in Mainstream Cigarette Smoke

Summary A diffusion denuder apparatus has been used to investigate the gas-particle partitioning of formaldehyde, acetaldehyde, acrolein and crotonaldehyde in cigarette mainstream smoke (MS), compounds that are of interest owing to their toxicity and near quantitative retention in the body during cigarette smoking. Formaldehyde showed the best performance in denuder experiments with simple aldehyde-air mixtures owing to the relatively fast rate of the heterogeneous reaction formaldehyde(g) + dinitrophenylhydrazine(s) → hydrazone(s). Analysis with the Gormley-Kennedy equation revealed that formaldehyde denuder removal approached, but did not attain, complete efficiency even under optimized operational conditions. Acetaldehyde, acrolein and crotonaldehyde were trapped with considerably lower efficiency than formaldehyde under the denuder conditions used, and more effective denuder wall coatings would be required to examine gas-particle partitioning of these other carbonyls. The proportion of formaldehyde in the smoke particulate phase initially entering the denuder was &gt; 99%, but loss of formaldehyde from the smoke particles was relatively rapid leading to 35%–61% deposition over the denuder length. The temperature dependence of formaldehyde deposition in the denuder was well predicted using Henry's law constant for aqueous formaldehyde solutions. These observed properties of formaldehyde are primarily due to reversible reactions of formaldehyde with water in cigarette smoke leading to the much less volatile species methanediol, its oligomers and hydrate. These data suggest that cigarette smoke inhalation is likely to expose the deeper-lung generations of smokers to greater relative formaldehyde exposure, and greater genotoxic risk at those generations than might occur through inhalation of formaldehyde vapour alone. Risk assessments of formaldehyde in cigarette smoke should be updated to recognise this modified risk profile.

MiR-425-5p Inhibits Rat Mesangial Cells (MCs) Proliferation by Targeting Transforming Growth Factor Beta (TGF-β)/RelA (p65) Under the Condition of Sitagliptin

Objective: Sitagliptin (Sitagtin) is widely involved in the treating process for several diseases in humans, covering DN (Diabetic Nephropathy). In the present research, the aim was at examining the roles of the miR-425-5p/TGFβ /P65 pathway in a DN rat model treated by Sitagtin. Methods: The subjects fed high-fat food were killed. Besides, new kidney specimens were placed in formaldehyde solution for histopathology-based observing process. Subsequently, Coomassie brilliant blue approach was used to determine urine protein excretion for 24 hours. Lastly, by bicinchoninic acid protein assay, proteins harvested from kidney tissue were detected. Results: Firstly, it was identified that miR-425-5p showed the highest expression in Sitagtin treatment cells compared to PBS treatment through miRNA microarray analysis. In addition, Sitagtin suppressed the HBZY-1 cell lines' proliferation, which may inhibit TGFβ /P65 expression through upregulating miR-425-5p. Furthermore, after HBZY-1 cells induced by high glucose (HG) were administrated with Sitagtin, miR-425-5p and si TGF /P65 inhibited HBZY-1 cells from proliferating. It was proved that TGFβ /P65 was one of the targeted genes of miR-425-5p. Lastly, TGFβ /P65 expression was decreased in the DN administrated with Sitagtin; the 24 h urinary protein excretion was decreased in Sitagtin-administrated DN rats. Conclusion: The study demonstrated that Sitagtin inhibited HBZY 1 cells through miR-4255p/TGFβ /P65 signaling.

Application of Sequential Changes of Dural Thickness and Biomechanical Parameters in Postmortem Interval Estimation.

Objective To study the relations of the dural thickness and the biomechanical parameters with postmortem interval （PMI） of human cadavers, and to explore the feasibility of the two indexes used for PMI estimation. Methods Dural samples were collected at different postmortem intervals of 6 h, 12 h, 18 h, 24 h, 30 h, 36 h, 48 h, 60 h, 72 h, 84 h and 96 h, then fabricated into 4.0 cm×1.0 cm A and B test specimens. The thickness of the A test specimen was measured, and the biomechanical parameters, such as ultimate load, maximum force deformation, tensile strength, elastic modulus and fracture force, were measured. The regression equations of thickness, biomechanical parameters and PMI were fitted respectively, and the difference between the predicted value and actual measured value of PMI was verified by the verification group. The B test specimen was fixed with 10% neutral formaldehyde solution, then tissue sections were prepared to observe its morphological changes. Results From 6 h to 96 h after death, the dural thickness decreased gradually, the collagen fibers gradually changed from clear arrangement to mutual fusion, and the number of nuclei decreased gradually. The dural thickness, ultimate load, tensile strength, elastic modulus and fracture force decreased sequentially, among which the dural thickness, ultimate load, elastic modulus and fracture force had a correlation with PMI （P<0.05）. In the return test, the difference between the predicted value and actual measured value of PMI in the verification group had no statistical significance （P>0.05）. Conclusion The dural thickness, ultimate load, elastic modulus and fracture force change sequentially from 6 h to 96 h after death. The regression equation established by the relationship between the changes and PMI can be used for PMI estimation.

Formolized Cadaveric Specimens Immersion‐Recovery Protocol

Cadaveric dissection, promoted by multiple anatomists and institutions as a fundamental area of medical education and training , requires embalming of the bodies to disinfect and preserve them. Therefore, despite being a known toxic and carcinogenic agent, formaldehyde is still widely used for its characteristics and results. Our objective is to introduce a Formolized Cadaveric Specimens Immersion‐Recovery Protocol developed at our laboratory, the chemical reagents used, performed processes and results. The protocol consists on specimen’s immersion in an aqueous solution of potassium hydroxide (KOH) for its maceration, this process causes chemical reactions like lipids saponification and proteins breakdown. The immersion time varies from one specimen to another; however, KOH concentration should never exceed 10% (w/v), otherwise tissue hydrolysis may occur. After a profuse wash, oxidative degradation is carried out: oxidizing formaldehyde into H2O and CO2 through the degradation of hydrogen peroxide (H2O2). It is extremely important to avoid the contact of this agent with the previously used KOH, which would cause the decomposition of H2O2 into H2O, O2 and hydroxyls, without obtaining a proper formaldehyde oxidation. For this purpose, sodium hypochlorite can also be used, with variable results. To ignore this chemical basis limits the achievement of ideal results. This processes allow to obtain 60% more joint movement on goniometry measures compared with formolized specimens, with a change from grey color generated by formaldehyde to ocher. Likewise, the degradation of formaldehyde allows obtaining minimum levels of it in treated specimens, thus reducing health impact on those who handle the specimens. After the recovery process, our specimens were preserved with a low formaldehyde solution. Anatomy students were invited to a peer‐guided extracurricular activity, they interacted with both formolized and recovered specimens, and a likert questionnaire was used to evaluate their experiences with both techniques. Students referred that recovered specimens looked more realistic and considered them better to work with. They also mentioned recovered corpses had less sensory hassles, like eye watering, airway irritation and coughing. Previous studies have compared Thiel solution and formaldehyde fixation. Thiel‐preserved bodies are considered to be a better choice on dissection and surgical training, since tissues offer a more realistic experience. Nonetheless, this technique has disadvantages such as higher costs, vacuum conservation, and the need of trained personal to handle the specimens. Moreover, some chemicals and infrastructure are not available worldwide. An example of the former scenario is present with Ammonium Nitrate, key component in Thiel’s, which is strictly regulated in several countriesSupport or Funding InformationAnatomy Laboratory, Universidad de Los Andes, School of Medicine