GNAT toxin may have a potential role in Pseudomonas aeruginosa persistence: an in vitro and in silico study.

Aims: Persistent cells are primarily responsible for developing antibiotic resistance and the recurrence of Pseudomonas aeruginosa. This study investigated the possible role of GNAT toxin in persistence. Materials & methods: P. aeruginosa was exposed to five MIC concentrations of ciprofloxacin. The expression levels of target genes were assessed. The GNAT/HTH system was bioinformatically studied, and an inhibitory peptide was designed to disrupt this system. Results: Ciprofloxacin can induce bacterial persistence. There was a significant increase in the expression of the GNAT toxin during the persistence state. A structural study of the GNAT/HTH system determined that an inhibitory peptide could be designed to block this system effectively. Conclusion: The GNAT/HTH system shows promise as a novel therapeutic target for combating P. aeruginosa infections.

Antibiotics are used to treat infections caused by bacteria. Over time, some of these infections have become more difficult to treat. This is because the bacteria can slow their growth and tolerate the antibiotic, known as persistence. It is important to find new ways to treat infections caused by persistent bacteria. This study researched a toxin­antitoxin system, called GNAT/HTH, that may play a role in bacterial persistence. This system could be a target for new antibiotics.

Chronicling Research and Practice Evolution in Pediatric Physical Therapy.

PURPOSE: To observe research and practice trends in the journal, Pediatric Physical Therapy, as a proxy for the field. METHODS: All issues of Pediatric Physical Therapy published from 1989 to 2019 were chronicled and summarized. Data were extracted regarding variables related to the issues and individual articles. RESULTS: The most common diagnosis studied was cerebral palsy. The proportion of studies involving middle childhood and adolescent-aged participants increased over time. Cohort studies and exercise were the most common study type and intervention studied, respectively. The proportion of scientific content in the journal increased. CONCLUSION: It is evident that pediatric physical therapy research has evolved over the past 30 years, both in rigor of articles published and in breadth of populations studied. WHAT THIS ADDS TO THE EVIDENCE: This review adds an in-depth evaluation of trends in the literature, facilitating the profession's continued growth.

Glutathione-dependent enzymes in the follicular fluid of the first-retrieved oocyte and their impact on oocyte and embryos in polycystic ovary syndrome: A cross-sectional study.

BACKGROUND: Oxidative stress and GSH-dependent antioxidant system plays a key role in the pathogenesis of polycystic ovary syndrome (PCOS). OBJECTIVE: We compared glutathione peroxidase (GPx) and glutathione reductase activities and reduced glutathione (GSH) levels in serum and follicular fluid (FF) of the first-retrieved follicle and their impact on quality of oocyte and embryo in PCOS women undergoing IVF. MATERIALS AND METHODS: This cross sectional study was conducted on 80 pairs of blood samples and FF of the first-retrieved follicle from PCOS women, at the Infertility center of Ghadir Mother and Child Hospital. The mean activity of GPx and GR, also GSH levels in the serum and FF were compared to the quality of the first follicle and resultant embryo. RESULTS: Retrieved oocytes included 53 (66.25%) MII, 17 (21.25%) MI, and 10 (12.5%) germinal vesicles; after IVF 42 (52.50%) embryos with grade I and 11 (13.75%) with grade II were produced. The mean values for all three antioxidants were higher in the FF compared to serum (p < 0.001). Also all of the mean measured levels were significantly higher in the FF of the MII oocytes compared to that of oocytes with lower grades (p = 0.012, 0.006 and 0.012, respectively). The mean GPX activity and GSH levels were significantly higher in the serum (p = 0.016 and 0.012, respectively) and FF (p = 0.001 for both) of the high-quality grade I embryos. CONCLUSION: GSH-dependent antioxidant system functions more efficiently in the FF of oocytes and embryos with higher quality.

A KHDC3L mutation resulting in recurrent hydatidiform mole causes genome-wide DNA methylation loss in oocytes and persistent imprinting defects post-fertilisation.

BACKGROUND: Maternal effect mutations in the components of the subcortical maternal complex (SCMC) of the human oocyte can cause early embryonic failure, gestational abnormalities and recurrent pregnancy loss. Enigmatically, they are also associated with DNA methylation abnormalities at imprinted genes in conceptuses: in the devastating gestational abnormality biparental complete hydatidiform mole (BiCHM) or in multi-locus imprinting disease (MLID). However, the developmental timing, genomic extent and mechanistic basis of these imprinting defects are unknown. The rarity of these disorders and the possibility that methylation defects originate in oocytes have made these questions very challenging to address. METHODS: Single-cell bisulphite sequencing (scBS-seq) was used to assess methylation in oocytes from a patient with BiCHM identified to be homozygous for an inactivating mutation in the human SCMC component KHDC3L. Genome-wide methylation analysis of a preimplantation embryo and molar tissue from the same patient was also performed. RESULTS: High-coverage scBS-seq libraries were obtained from five KHDC3Lc.1A>G oocytes, which revealed a genome-wide deficit of DNA methylation compared with normal human oocytes. Importantly, germline differentially methylated regions (gDMRs) of imprinted genes were affected similarly to other sequence features that normally become methylated in oocytes, indicating no selectivity towards imprinted genes. A range of methylation losses was observed across genomic features, including gDMRs, indicating variable sensitivity to defects in the SCMC. Genome-wide analysis of a pre-implantation embryo and molar tissue from the same patient showed that following fertilisation methylation defects at imprinted genes persist, while most non-imprinted regions of the genome recover near-normal methylation post-implantation. CONCLUSIONS: We show for the first time that the integrity of the SCMC is essential for de novo methylation in the female germline. These findings have important implications for understanding the role of the SCMC in DNA methylation and for the origin of imprinting defects, for counselling affected families, and will help inform future therapeutic approaches.

Itch and psyche: psychiatric aspects of pruritus.

Itch, also referred to as pruritus, is an unpleasant cutaneous sensation provoking the desire to scratch. It is often an uncomfortable, subjective sensation responsible for decreased quality of life in a variety of psychodermatological conditions. Comorbid psychiatric conditions, including depression and anxiety, are frequently associated with itch and scratch cycle. The reciprocal and intricate relationship between the psyche and itch has been widely studied. The neurobiology of itch involves the complexity of specific mediators, itch-related neuronal pathways, and central processing of itch. The connection between itch and the psyche can be grouped under three headings: pruritic diseases with psychosocial sequelae, pruritic diseases aggravated by psychosocial factors, and psychiatric disorders causing pruritus. Itch and pain modulation go together in most circumstances and involve various substances including histamine, interleukins, protease-activated receptors, transient receptor potential receptors, opioids, and cannabinoids. The close interaction between keratinocytes and nerve endings modulating pain and itch also play a major role. Management of itch associated with its psychosomatic components is directed at an underlying cause and adopting a holistic approach to address not only dermatologic and somatosensory aspects, but also the cognitive, emotional, and psychosocial components. An integrated multidisciplinary team consisting of a dermatologist, psychiatrist, psychologist, and social worker is vital in addressing the multifaceted aspects of pruritus.

Detection of Y Chromosome Microdeletions and Hormonal Profile Analysis of Infertile Men undergoing Assisted Reproductive Technologies.

BACKGROUND: Y chromosome deletions (YCDs) in azoospermia factor (AZF) region are associated with abnormal spermatogenesis and may lead to azoospermia or severe oligozoospermia. Assisted reproductive technologies (ART) by intracytoplasmic sperm injection (ICSI) and testicular sperm extraction (TESE) are commonly required for infertility management of patients carrying YCDs. The aim of this study was to estimate the frequency of YCDs, to find the most frequent variant in infertile men candidate for ART and to compare YCD distribution with a control fertile group. The semen parameters, hormonal profiles and ART outcomes of the infertile group were studied. MATERIALS AND METHODS: This case-control study consisted of 97 oligozoospermic or non-obstructive azoospermic (NOA) infertile men, who had undergone ART, as the case group and 100 fertile men as the control group. DNA samples were extracted from blood samples taken from all 197 participants and YCDs were identified by multiplex polymerase chain reaction (PCR) of eight known sequence-tagged sites. The chi-square test was used to compare the mean values of hormone and sperm parameters between the two groups. P<0.05 was considered statistically significant. RESULTS: No YCD was detected in the control group. However, 20 out of 97 (20.6%) infertile men had a YCD. AZFc, AZFbc and AZFabc deletions were detected in 15 (75%), four (20%) and one (5%) YCD-positive patients. No fertilization or clinical pregnancy was seen following ICSI in this sub-group with YCD. The mean level of FSH was significantly higher in the group with YCD (28.45 ± 22.2 vs. 4.8 ± 3.17 and 10.83 ± 7.23 in YCD-negative patients with and without clinical pregnancy respectively). CONCLUSION: YCD is frequent among NOA men and YCD screening before ART and patient counseling is thus strongly recommended.

The potential role of granulosa cells in the maturation rate of immature human oocytes and embryo development: A co-culture study.

OBJECTIVE: In order to increase the number of mature oocytes usable for intracytoplasmic sperm injection (ICSI), we aimed to investigate the effect of co-culturing granulosa cells (GCs) on human oocyte maturation in vitro, the fertilization rate, and embryo development. METHODS: A total of 133 immature oocytes were retrieved and were randomly divided into two groups; oocytes that were cultured with GCs (group A) and oocytes that were cultured without GCs (group B). After in vitro maturation, only oocytes that displayed metaphase II (MII) underwent the ICSI procedure. The maturation and fertilization rates were analyzed, as well as the frequency of embryo development. RESULTS: The mean age of the patients, their basal levels of follicle-stimulating hormone, and the number of oocytes recovered from the patients were all comparable between the two study groups. The number of oocytes that reached MII (mature oocytes) was 59 out of 70 (84.28%) in group A, compared to 41 out of 63 (65.07%) in group B (p=0.011). No significant difference between fertilization rates was found between the two study groups (p=0.702). The embryo development rate was higher in group A (33/59, 75%) than in group B (12/41, 42.85%; p=0.006). The proportion of highest-quality embryos and the blastocyst formation rate were significantly lower in group B than in group A (p=0.003 and p<0.001, respectively). CONCLUSION: The findings of the current study demonstrate that culturing immature human oocytes with GCs prior to ICSI improves the maturation rate and the likelihood of embryo development.

Effects of impression levels and trays on the accuracy of impressions taken from angulated implants.

BACKGROUND AND PURPOSE: It is crucial to keep the misfit of the abutment-fixture unit at the lowest possible rate. There are a few controversial studies on the accuracy of impression making of angulated implants, and much fewer (and controversial) studies on the abutment-level impression technique, which is a convenient and clinically favorable method. Besides, there are no studies on comparison of sectional vs. full-arch trays. We aimed to assess these. METHODS: A trapezoidal model with four angulated implants installed at 20° and 30° buccal tilts was fabricated. Forty impressions were taken from this model, with two groups of full-arch and sectional custom trays (n = 2 × 20), each divided into two subgroups of implant-level and abutment-level techniques (n = 2 × 2 × 10 in four subgroups). Absolute and non-absolute linear and angular impression errors were estimated by comparing the fabricated casts with the model, using a coordinate measuring machine. The effects of sectional/full-arch trays and abutment-level and fixture-level techniques on impression accuracies were analyzed using one- and two-way analyses of variance (ANOVA), Tukey, Mann-Whitney, and one-sample t-tests (α = 0.05, Mann-Whitney's α using the Bonferroni Bonferroni method). RESULTS: No significant differences between the absolute linear errors of the two trays (P = 0.100 [ANOVA]) and the two levels (P = 0.400 [ANOVA]) were observed. The assessment of absolute angular errors showed no significant differences (all P values ≥ 0.4 [ANOVA]). The difference between the linear errors in the full-arch vs. sectional trays was not significant in the fixture-level group (P = 0.290). However, in the abutment-level group, the linear error was significantly greater in the sectional tray compared to full-arch tray (P = 0.013, α = 0.025 [Mann-Whitney]). CONCLUSIONS: Using sectional trays might not be advantageous over full-arch trays. Sectional trays are not recommended for taking abutment-level impressions. The abutment-level impression technique is as accurate as the studied fixture-level technique. Increasing the angle of implants' divergence from 40° to 60° might not usually lead to a significant increase in the errors, particularly when using abutment-level impressions.