Use of copper-functionalized cotton waste in combined chemical and biological processes for production of valuable chemical compounds

Cotton textiles modified with copper compounds have a documented mechanism of antimicrobial action against bacteria, fungi, and viruses. During the COVID-19 pandemic, there was pronounced interest in finding new solutions for textile engineering, using modifiers and bioactive methods of functionalization, including introducing copper nanoparticles and complexes into textile products (e.g. masks, special clothing, surface coverings, or tents). However, copper can be toxic, depending on its form and concentration. Functionalized waste may present a risk to the environment if not managed correctly. Here, we present a model for managing copper-modified cotton textile waste. The process includes pressure and temperature-assisted hydrolysis and use of the hydrolysates as a source of sugars for cultivating yeast and lactic acid bacteria biomass as valuable chemical compounds.

Socioeconomic position, immune function, and its physiological markers

The development of costly traits such as immune function and secondary sexual traits is constrained by resource availability. The quality of developmental conditions and the availability of resources in ontogeny may therefore influence immune system functions and other biological traits. We analyzed causal pathways between family socioeconomic position, strength of immune response, and five physiological biomarkers in young Latvian men (n = 93) using structural equation modeling. Men from wealthier families had higher testosterone levels (r_s = 0.280), stronger immune response (r_s = 0.551), and higher facial attractiveness (r_s = 0.300). There were weak, non-significant correlations between family income, body fat percentage (r_s = -0.147), and fluctuating asymmetry (r_s = -0.159). Testosterone partially (33.8%) mediated the effect of family income on facial masculinity. Testosterone (positively) and adiposity (negatively) partially (4%) mediated the relationship between family income and immune function. Higher facial masculinity, higher facial symmetry, and lower adiposity were reliable and independent cues of better immune function (R² = 0.238) in a larger sample of young Latvian men (N = 146). Resource availability in ontogeny has an important role for the development of immune function and physical appearance, and it is a key parameter to be included in human eco-immunological research.

The Obesity Paradox Predicts the Second Wave of COVID-19 to Be Severe in Western Countries

While COVID-19 infection and mortality rates are soaring in Western countries, Southeast Asian countries have successfully avoided the second wave of the SARS-CoV-2 pandemic despite high population density. We provide a biochemical hypothesis for the connection between low COVID-19 incidence, mortality rates, and high visceral adiposity in Southeast Asian populations. The SARS-CoV-2 virus uses angiotensin-converting enzyme 2 (ACE2) as a gateway into the human body. Although the highest expression levels of ACE2 are found in people’s visceral adipose tissue in Southeast Asia, this does not necessarily make them vulnerable to COVID-19. Hypothetically, high levels of visceral adiposity cause systemic inflammation, thus decreasing the ACE2 amount on the surface of both visceral adipocytes and alveolar epithelial type 2 cells in the lungs. Extra weight gained during the pandemic is expected to increase visceral adipose tissue in Southeast Asians, further decreasing the ACE2 pool. In contrast, weight gain can increase local inflammation in fat depots in Western people, leading to worse COVID-related outcomes. Because of the biological mechanisms associated with fat accumulation, inflammation, and their differential expression in Southeast Asian and Western populations, the second wave of the pandemic may be more severe in Western countries, while Southeast Asians may benefit from their higher visceral fat depots.

Conjugates of Copper Alginate with Arginine-Glycine-Aspartic Acid (RGD) for Potential Use in Regenerative Medicine

Current restrictions on the use of antibiotics, associated with increases in bacterial resistance, require new solutions, including materials with antibacterial properties. In this study, copper alginate fibers obtained using the classic wet method were used to make nonwovens which were modified with arginine-glycine-aspartic acid (RGD) derivatives. Stable polysaccharide-peptide conjugates formed by coupling with 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium toluene-4-sulfonate (DMT/NMM/TosO-), and materials with physically embedded RGD derivatives, were obtained. The materials were found to be characterized by very high antibacterial activity against S. aureus and K. pneumoniae. Cytotoxicity studies confirmed that the materials are not cytotoxic. Copper alginate conjugates with RGD peptides have strong potential for use in regenerative medicine, due to their biocompatibility and innate antibacterial activity.

Distance Dependence of Single-Molecule Energy Transfer to Graphene Measured with DNA Origami Nanopositioners

Despite the thorough investigation of graphene since 2004, altering its surface chemistry and reproducible functionalization remain challenging. This hinders fabrication of more complex hybrid materials with controlled architectures, and as a consequence the development of sensitive and reliable sensors and biological assays. In this contribution, we introduce DNA origami structures as nanopositioners for placing single dye molecules at controlled distances from graphene. The measurements of fluorescence intensity and lifetime of single emitters carried out for distances ranging from 3 to 58 nm confirmed the d^-4 dependence of the excitation energy transfer to graphene. Moreover, we determined the characteristic distance for 50% efficiency of the energy transfer from single dyes to graphene to be 17.7 nm. Using pyrene molecules as a glue to immobilize DNA origami nanostructures of various shape on graphene opens new possibilities to develop graphene-based biophysics and biosensing.

The effectiveness of chemotherapy and electrochemotherapy on ovarian cell lines in vitro

The presented study aimed to evaluate in vitro the effectiveness of improvement standard chemotherapy with bleomycin by electroporation in two various ovarian cancer cell lines. Two human ovarian cell lines OvBH-1 and SKOV-3 were used. The lines were selected because of their resistance to several therapeutic methods. As anticancer drug we use range of concentrations of bleomycin. In EP and ECT experiments different voltage values: from 0 to 1200 V/cm, 8 pulses with duration of 100μs and intervals between pulses 1s long were used. The cells viability after applied treatments was evaluated by MTT assay. The expression of heat shock proteins - HSP27 was examined by immunocytochemical ABC method.The cytotoxicity with different concentrations of bleomycin alone was not significantly decrease in both cell lines. It confirms resistance of these cells to conventional chemotherapy. The highest decrease of cell proliferation was observed after EP with bleomycin after 48h of incubation for 1000 V/cm. The intensity of expression of small heat shock proteins HSP27 slightly increased after ECT in both treated cell lines, in particular in OvBH-1. The presented study indicated that application of electroporation may effectively enhance chemotherapy with bleomycin, particularly in the case of treating ovarian cancer resistant to standard therapy.

The time-dependent health and biochemical effects in rats exposed to stainless steel welding dust and its soluble form

Welding processes that generate fumes containing toxic metals, such as hexavalent chromium (Cr(VI)), manganese (Mn), and nickel (Ni), have been implicated in lung injury, inflammation, and lung tumor promotion in animal models. The principal objective of this study was to determine the dynamics of toxic effects of inhalation exposure to morphologically rated welding dust from stainless steel welding and its soluble form in TSE System with a dynamic airflow. We assessed the pulmonary toxicity of welding dust in Wistar rats exposed to 60.0 mg/m³ of respirable-size welding dust (mean diameter 1.17 µm) for 2 weeks (6 h/day, 5 days/week); the aerosols were generated in the nose-only exposure chambers (NOEC). An additional aim included the study of the effect of betaine supplementation on oxidative deterioration in rat lung during 2 weeks of exposure to welding dust or water-soluble dust form. The animals were divided into eight groups (n = 8 per group): control, dust, betaine, betaine + dust, soluble-form dust, soluble-form dust + betaine, saline and saline + betaine groups. Rats were euthanized 1 or 2 weeks after the last exposure for assessment of pulmonary toxicity. Differential cell counts, total protein concentrations and cellular enzyme (lactate dehydrogenase-LDH) activities were determined in bronchoalveolar lavage (BAL) fluid, and corticosterone and thiobarbituric acid reactive substances (TBARS) concentrations were assessed in serum. The increase in polymorphonuclear (PMN) leukocytes in BAL fluid (a cytological index of inflammatory responses of the lung) is believed to reflect pulmonary toxicity of heavy metals. Biomarkers of toxicity assessed in bronchoalveolar fluids indicate that the level of the toxic effect depends mainly on the solubility of studied metal compounds; biomarkers that showed treatment effects included: total cell, neutrophil and lymphocyte counts, total protein concentrations, and cellular enzyme (lactate dehydrogenase) activity. Betaine supplementation at 250 mg/kg/day in all study rats groups attenuated stress indices, and corticosterone and TBARS serum levels, and simultaneously stimulated increase of polymorphonuclear cells in BALF of rats. The study confirmed deleterious effect of transitory metals and particles during experimental inhalation exposure to welding dusts, evidenced in the lungs and brain by increased levels of total protein, higher cellular influx, rise of LDH in BALF, elevated TBARS and increased corticosterone in serum of rats. Our result confirm also the hypothesis about the effect of the welding dusts on the oxidative stress responsible for disturbed systemic homeostasis and impairment of calcium regulation.

EFFECT OF NALTREXONE ADMINISTRATION ON SHORT-TERM MEMORY IN CHRONICALLY ETHANOL-TREATED OUTBRED RATS

AIMS

The purpose of this study was to evaluate the effect of naltrexone treatment for 21 consecutive days on short-term memory in ethanol-preferring and non-preferring outbred rats.

METHODS

Ethanol preferring, non-preferring and control Wistar rats were treated with naltrexone [0.1 mg/kg intraperitoneally (i.p.)] for 21 consecutive days. Short-term memory was assessed by using an olfactory social recognition test.

RESULTS

A single administration of naltrexone (0.1 mg/kg i.p.) to non-ethanol-treated animals facilitated social memory, whereas the drug did not affect short-term memory in either group of chronically ethanol-treated rats. Multiple naltrexone treatment also lowered alcohol intake in ethanol-preferring rats.

CONCLUSION

Naltrexone-ethanol interaction does not seem to produce any negative effect on the short-term memory in outbred rats.

Bilateral chronic subdural hematomas with neurologic symptoms complicating spinal anesthesia

BACKGROUND AND OBJECTIVES

Intracranial subdural hematoma is a rare but potentially fatal complication of spinal anesthesia (SA). This case is intended to highlight the importance of careful follow-up of patients with a chronic headache that develops after SA.

CASE REPORT

A 38-year-old woman underwent saphenous vein ligation for varices under SA. On the first postoperative day, she complained of severe postural headache that was controllable with oral analgesics. Two weeks later, bilateral abducens nerve palsy with diplopia developed. Brain magnetic resonance imaging (MRI) showed small bilateral subdural hygromas. Diplopia and headache (no longer postural) were relieved after administration of dexamethasone, but reappeared 6 wks later. This time, MRI showed large subdural hematomas. The patient was treated with burr-hole decompression.

CONCLUSIONS

Persistent headache after SA requires careful neurologic and radiologic follow-up for exclusion of chronic intracranial bleeding. Pharmacologic treatment may mask some neurologic symptoms and delay diagnosis of intracranial complications related to SA.