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Much attention has been paid to chitosan biopolymer for advanced wound dressing owing to its exceptional biological characteristics comprising biodegradability, biocompatibility and respectable antibacterial activity. This study intended to develop a new antibacterial membrane based on quaternized aminochitosan (QAMCS) derivative. Herein, aminochitosan (AMCS) derivative was quaternized by N-(2-Chloroethyl) dimethylamine hydrochloride with different ratios. The pre-fabricated membranes were characterized by several analysis tools. The results indicate that maximum surface potential of +42.2 mV was attained by QAMCS3 membrane compared with +33.6 mV for native AMCS membrane. Moreover, membranes displayed higher surface roughness (1.27 ± 0.24 μm) and higher water uptake value (237 ± 8%) for QAMCS3 compared with 0.81 ± 0.08 μm and 165 ± 6% for neat AMCS membranes. Furthermore, the antibacterial activities were evaluated against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus cereus. Superior antibacterial activities with maximum inhibition values of 80–98% were accomplished by QAMCS3 membranes compared with 57–72% for AMCS membrane. Minimum inhibition concentration (MIC) results denote that the antibacterial activities were significantly boosted with increasing of polymeric sample concentration from 25 to 250 µg/mL. Additionally, all membranes unveiled better biocompatibility and respectable biodegradability, suggesting their possible application for advanced wound dressing.

BACKGROUND:Maternal smoking during pregnancy has repeatedly been associated with decreased sperm counts in sons. Nevertheless, our team recently detected a lower total sperm count in the sons of smoking fathers as compared to sons of non-smoking fathers. Since paternal and maternal tobacco smoking often coincide, it is difficult to discriminate whether effects are mediated paternally or maternally when using questionnaire- or register-based studies. Therefore, getting an objective measure of the maternal nicotine exposure level during pregnancy might help disentangling the impact of paternally and maternally derived exposure. OBJECTIVES:Our aim was to study how paternal smoking at the time of the pregnancy was associated with semen quality in the sons after adjusting for the maternal levels of nicotine exposure during pregnancy. METHODS:We recruited 104 men (17-20 years old) from the general Swedish population. The participants answered a questionnaire about paternal smoking. Associations between smoking and semen volume, total sperm count, sperm concentration, morphology and motility were adjusted for levels of the nicotine metabolite cotinine in stored maternal serum samples obtained from rubella screening between the 6th and 35th week of pregnancy. We additionally adjusted for the estimated socioeconomic status. RESULTS:After adjusting for the maternal cotinine, the men of smoking fathers had 41% lower sperm concentration and 51% lower total sperm count than the men of non-smoking fathers (p = 0.02 and 0.003, respectively). This was robust to the additional adjustment. CONCLUSIONS:Our results suggest a negative association between paternal smoking and sperm counts in the sons, independent of the level maternal nicotine exposure during the pregnancy.

Prenatal heavy metals exposure has shown a negative impact on birth weight. However, their influence on different clinical forms of fetal smallness was never assessed.To investigate whether there is a differential association between heavy metals exposure and fetal smallness subclassification into intrauterine growth restriction (IUGR) and small-for-gestational age (SGA).In this prospective case-control study, we included 178 mother-infant pairs; 96 of appropriate for gestational age (AGA) and 82 of small fetuses diagnosed in third trimester. The small ones were further subclassified into IUGR, n = 49 and SGA, n = 33. Cadmium (Cd), mercury (Hg), lead (Pb), arsenic (As) and zinc (Zn) levels were measured in the maternal and cord serum, and in the placentas of the three groups.Maternal serum level of Cd (p