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The key role of a thyroid hormone receptor in determining the maturation and diversity of cone photoreceptors reflects a profound influence of endocrine signaling on the cells that mediate color vision. However, the route by which hormone reaches cones remains enigmatic as cones reside in the retinal photoreceptor layer, shielded by the blood--retina barrier. Using genetic approaches, we report that cone differentiation is regulated by a membrane transporter for thyroid hormone, MCT8 (SLC16A2), in the retinal pigment epithelium (RPE), which forms the outer blood-retina barrier. Mct8-deficient mice display hypothyroid-like cone gene expression and compromised electroretinogram responses. Mammalian color vision is typically facilitated by cone types that detect medium-long (M) and short (S) wavelengths of light but Mct8-deficient mice have a partial shift of M to S cone identity, resembling the phenotype of thyroid hormone receptor deficiency. RPE-specific ablation of Mct8 results in similar shifts in cone identity and hypothyroid-like gene expression whereas reexpression of MCT8 in the RPE in Mct8-deficient mice partly restores M cone identity, consistent with paracrine-like control of thyroid hormone signaling by the RPE. Our findings suggest that in addition to transport of essential solutes and homeostatic support for photoreceptors, the RPE regulates the thyroid hormone signal that pro-motes cone-mediated vision. [ABSTRACT FROM AUTHOR]

Purpose: To identify germline mutations related to azoospermia etiology and reproductive potential of surgically retrieved spermatozoa, and to investigate the feasibility of predicting seminiferous tubule function of nonobstructive azoospermic men by transcriptomic profiling of ejaculates. Materials and methods: Sperm specimens were obtained from 30 men (38.4 ± 6 years) undergoing epididymal sperm aspiration for obstructive azoospermia (OA, n = 19) acquired by vasectomy, or testicular biopsy for nonobstructive azoospermia (NOA, n = 11). To evaluate for a correlation with azoospermia etiology, DNAseq was performed on surgically retrieved spermatozoa, and cell-free RNAseq on seminal fluid (n = 23) was performed to predict spermatogenesis in the seminiferous tubule. Results: Overall, surgically retrieved sperm aneuploidy rates were 1.7% and 1.8% among OA and NOA cohorts, respectively. OA men carried housekeeping-related gene mutations, while NOA men displayed mutations on genes involved in crucial spermiogenic functions (AP1S2, AP1G2, APOE). We categorized couples within each cohort according to ICSI clinical outcomes to investigate genetic causes that may affect reproductive potential. All OA-fertile men (n = 9) carried mutations in ZNF749 (sperm production), whereas OA-infertile men (n = 10) harbored mutations in PRB1, which is essential for DNA replication. NOA-fertile men (n = 8) carried mutations in MPIG6B (stem cell lineage differentiation), whereas NOA-infertile individuals (n = 3) harbored mutations in genes involved in spermato/spermio-genesis (ADAM29, SPATA31E1, MAK, POLG, IFT43, ATG9B) and early embryonic development (MBD5, CCAR1, PMEPA1, POLK, REC8, REPIN1, MAPRE3, ARL4C). Transcriptomic assessment of cell-free RNAs in seminal fluid from NOA men allowed the prediction of residual spermatogenic foci. Conclusions: Sperm genome profiling provides invaluable information on azoospermia etiology and identifies gene-related mechanistic links to reproductive performance. Moreover, RNAseq assessment of seminal fluid from NOA men can help predict sperm retrieval during testicular biopsies. [ABSTRACT FROM AUTHOR]

The effects of climatic warming on tropical streams have received little attention, and field studies of such changes are generally lacking. Drifting insects from a Hong Kong forest stream were sampled for 36 months between 2013 and 2016, and compared with samples collected using identical methods in 1983–84. Mean air temperatures rose by ~0.5°C (0.17°C per decade) over this period. The stream drained an uninhabited protected area, so no climate‐change effects were confounded by anthropogenic disturbance. In total, 105 taxa and >77,000 individuals were collected. Richness of samples in the historic and contemporary datasets did not differ, but true diversity of drifting insects was highest in 1983–84, and declined between 2013–14 and 2015–16. There was considerable disparity in assemblage composition between 1983–84 and 2013–16, and smaller between‐year changes in the contemporary dataset. Nine indicator species of the historic dataset were identified. Most were mayflies, particularly Baetidae, which were greatly reduced in relative abundance in 2013–16. Diptera became more numerous, and tanypodine chironomids were the sole contemporary indicator taxon. Relative abundance of eight of 19 drifting species (comprising 60% of total insects) was lower in 2013–16, when the dominant baetid mayfly during 1983–84 had declined by almost 90%; only one of the 19 species occurred at higher abundance. Eight species were affected by seasonal temperature variability, but these responses were not correlated with any tendency to exhibit long‐term changes in abundance. Substantial shifts in composition, including declines in mayfly relative abundance and assemblage diversity, occurred after three decades of warming, despite the broad annual range of stream temperatures (~16°C) in Hong Kong. This contradicts the well‐known prediction that organisms from variable climates have evolved wider thermal tolerances that reflect prevailing environmental conditions. The observed compositional reorganization indicates that variability, rather than stability, may be typical of undisturbed tropical stream communities. [ABSTRACT FROM AUTHOR]

IR reflection-absorption spectroscopy has been employed to study K–CO interactions on Ni(111) at high resolution. It has been found that a mixture of long range and short range interactions are discernible. An ensemble of as many as ∼25 CO molecule/K is affected by the long range K· · ·CO interaction. In addition, Kδ+x(CO)δ-y complexes produced by short range electrostatic effects are observed, yielding characteristic C–O stretching frequencies. [ABSTRACT FROM AUTHOR]

This study investigated the clinical features of anaerobic bacteraemia in an acute-care hospital, and evaluated the antimicrobial susceptibility of these isolates to commonly available antibiotics. Microbiological and epidemiological data from 2009 to 2011were extracted from the laboratory information system and electronic medical records. One hundred and eleven unique patient episodes consisting of 116 anaerobic isolates were selected for clinical review and antibiotic susceptibility testing. Susceptibilities to amoxicillin-clavulanate, clindamycin, imipenem, metronidazole, moxifloxacin, penicillin and piperacillin-tazobactam were performed using Etest strips with categorical interpretations according to current CLSI breakpoints. Metronidazole-resistant and carbapenem-resistant anaerobic Gram-negative bacilli were screened for the nim and cfiA genes. Clinical data was obtained retrospectively from electronic medical records. During the 3 year period, Bacteroides fragilis group (41%), Clostridium species (14%), Propionibacterium species (9%) and Fusobacterium species (6%) were the most commonly isolated anaerobes. Patients with anaerobic bacteraemia that were included in the study were predominantly above 60 years of age, with community-acquired infections. The most commonly used empiric antibiotic therapies were beta-lactam/beta-lactamase inhibitor combinations (44%) and metronidazole (10%). The crude mortality was 25%, and appropriate initial antibiotic therapy was not significantly associated with improved survival. Intra-abdominal infections (39%) and soft-tissue infections (33%) accounted for nearly three-quarters of all bacteraemia. Antibiotics with the best anaerobic activity were imipenem, piperacillin-tazobactam, amoxicillin-clavulanate and metronidazole, with in-vitro susceptibility rates of 95%, 95%, 94% and 92% respectively. Susceptibilities to penicillin (31%), clindamycin (60%) and moxifloxacin (84%) were more variable. Two multidrug-resistant isolates of Bacteroides species were positive for nim and cfiA genes respectively, while another two imipenem-resistant Fusobacterium species were negative for cfiA genes. This study demonstrated that anaerobic bacteraemia in our patient population was predominantly associated with intra-abdominal and soft-tissue infections. Overall antibiotic resistance was high for penicillin and clindamycin, and the presence of emerging resistance to carbapenems and metronidazole warrants further monitoring. [ABSTRACT FROM AUTHOR]

The senses are our window to the world, our interface with the habitat in which we live in and the basis for our communication with each other. Although sensory systems are not generally viewed as major targets of endocrine regulation, sensory development is profoundly influenced by thyroid hormone (T3) signalling. In this article, we discuss this developmental role of T3 and highlight the auditory system as the best-studied example of the interplay between systemic and local tissue mechanisms by which T3 stimulates the onset of sensory function. Several genes that mediate the action of T3 are known to promote sensory development in mice, including genes that encode T3 receptors and deiodinase enzymes that amplify or deplete levels of T3. We also discuss the current knowledge of sensory defects in human genetic disorders in which T3 signalling is impaired. As sensory input provides the only means of acquiring information from the environment, the stimulation of sensory development is one of the most fundamental functions of T3 signalling. [ABSTRACT FROM AUTHOR]

The senses are our window to the world, our interface with the habitat in which we live in and the basis for our communication with each other. Although sensory systems are not generally viewed as major targets of endocrine regulation, sensory development is profoundly influenced by thyroid hormone (T(3)) signalling. In this article, we discuss this developmental role of T(3) and highlight the auditory system as the best-studied example of the interplay between systemic and local tissue mechanisms by which T(3) stimulates the onset of sensory function. Several genes that mediate the action of T(3) are known to promote sensory development in mice, including genes that encode T(3) receptors and deiodinase enzymes that amplify or deplete levels of T(3). We also discuss the current knowledge of sensory defects in human genetic disorders in which T(3) signalling is impaired. As sensory input provides the only means of acquiring information from the environment, the stimulation of sensory development is one of the most fundamental functions of T(3) signalling. [ABSTRACT FROM AUTHOR]

Maturation of the mammalian nervous system requires adequate provision of thyroid hormone and mechanisms that enhance tissue responses to the hormone. Here, we report that the development of cones, the photoreceptors for daylight and color vision, requires protection from thyroid hormone by type 3 deiodinase, a thyroid hormone-inactivating enzyme. Type 3 deiodinase, encoded by Dio3, is expressed in the immature mouse retina. In Dio3-/- mice, ~80% of cones are lost through neonatal cell death. Cones that express opsin photopigments for response to both short (S) and medium-long (M) wavelength light are lost. Rod photoreceptors, which mediate dim light vision, remain essentially intact. Excessive thyroid hormone in wild-type pups also eliminates cones. Cone loss is mediated by cone-specific thyroid hormone receptor β2 (TRβ2) as deletion of TRβ2 rescues cones in Dio3-/- mice. However, rescued cones respond to short but not longer wavelength light because TRβ2 under moderate hormonal stimulation normally induces M opsin and controls the patterning of M and S opsins over the retina. The results suggest that type 3 deiodinase limits hormonal exposure of the cone to levels that safeguard both cone survival and the patterning of opsins that is required for cone function. [ABSTRACT FROM AUTHOR]

Abstract: Data from an 800-bed hospital showed an increase in the incidence density of ceftriaxone-resistant Escherichia coli, from 13.1 to 21.7 per 100 000 inpatient days over a 4-year period. Detailed testing performed on 54 E. coli isolates showed bla CTX-M extended-spectrum β-lactamase (ESBL) genes (n = 37) and bla CMY-like ampC genes (n = 15). Typing data showed only limited clonal transmission in isolates with ESBL. [Copyright &y& Elsevier]

Rates of gambling problems in older adults have risen with increased accessibility of gambling venues. One possible contributor to problem gambling among older adults is decreased self-control brought about by diminished executive functioning. Consistent with this possibility, Study 1 revealed that older adults recruited from gambling venues reported greater gambling problems if they also experienced deficits in executive functioning, measured via the Trail Making Test. Study 2 replicated this finding and demonstrated that problem gambling is associated with increased depression among older adults, mediated by increased financial distress. These studies provide support for the hypothesis that older adult gamblers who have executive functioning problems are also likely to have gambling problems. [ABSTRACT FROM AUTHOR]

Abstract: Treatment options are increasingly limited for carbapenem-resistant Acinetobacter baumannii. This study set out to determine the in vitro susceptibility of multiresistant Acinetobacter spp. to colistin, minocycline, and rifampicin using agar dilution, and to compare the accuracy of testing results obtained from an automated susceptibility testing system (Vitek 2). MICs for colistin, minocycline, and rifampicin were obtained by agar dilution and Vitek 2 for 44 unrelated strains of multiresistant Acinetobacter spp. All tested strains were susceptible to colistin, whereas 61% were susceptible to minocycline and 52% were susceptible to rifampicin. Results for colistin testing showed categoric agreement between Vitek 2 and agar dilution, with no false-resistance reported by Vitek 2. However, there was a poor agreement for minocycline and rifampicin when results obtained from Vitek 2 testing were compared with those obtained by agar dilution. [Copyright &y& Elsevier]

Color vision is facilitated by distinct populations of cone photoreceptors in the retina. In rodents, cones expressing different opsin photopigments are sensitive to middle (M, 'green') and short (S, 'blue') wavelengths, and are differentially distributed across the retina. The mechanisms that control which opsin is expressed in a particular cone are poorly understood, but previous in vitro studies implicated thyroid hormone in cone differentiation. Thyroid hormone receptor β2 (TRβ2) is a ligand-activated transcription factor that is expressed in the outer nuclear layer of the embryonic retina. Here we delete Thrb (encoding Trβ2) in mice, causing the selective loss of M-cones and a concomitant increase in S-opsin immunoreactive cones. Moreover, the gradient of cone distribution is disturbed, with S-cones becoming widespread across the retina. The results indicate that cone photoreceptors throughout the retina have the potential to follow a default S-cone pathway and reveal an essential role for Trβ2 in the commitment to an M-cone identity. Our findings raise the possibility that Thrb mutations may be associated with human cone disorders. [ABSTRACT FROM AUTHOR]

Introduction: Pregnancy is a risk factor for hernia development. This review studies the natural history and outcomes of hernias in pregnant women treated in the Hong Kong West Cluster. Methods: This is a cluster‐wide, retrospective descriptive study. Electronic medical records of women attending Hernia Clinics at Tung Wah Hospital or Queen Mary Hospital or those emergently admitted into the surgical department between January 2002 and January 2022 were screened. Inclusion criteria were women with: (i) hernia developed during pregnancy; and (ii) known unrepaired hernia developed prior to pregnancy. Results: Forty‐one patients were included. Median age of hernia onset was 31 years old. All patients continued with pregnancy with no hernia complications. None received hernia repair before delivery. Nine out of 41 patients (22.0%) received Caesarean section. Fourteen out of 22 (63.6%) patients with inguinal hernias developed during pregnancy reported hernia disappearance after delivery, of whom five experienced hernia recurrence. One out of five patients with ventral hernia developed during pregnancy experienced hernia disappearance after delivery with no recurrence. 43.9% received hernia repair after delivery. Conclusions: It is safe to adopt conservative management in pregnant women. Vaginal delivery is not contraindicated. We recommend watchful waiting during pregnancy and repair after delivery. [ABSTRACT FROM AUTHOR]

Focuses on developments in infrared spectroscopy between October 1996 and October 1998. Clinical applications; Laboratory analyses of pathological samples; Noninvasive in vivo monitoring.

Abstract: This study investigated the effect of different Mueller–Hinton agars and media age on tigecycline MICs, obtained by Etest. Variations in MIC values on different Mueller–Hinton were noted, which may result in changes in categoric susceptibility. The use of stored Mueller–Hinton media had minimal effect on MIC values. [ABSTRACT FROM AUTHOR]

Introduction: Spigelian hernia is a rare lateral ventral hernia traditionally repaired through open incision with extensive dissection. Three laparoscopic techniques have been reported in the literature: intraperitoneal onlay mesh (IPOM), transabdominal preperitoneal (TAPP), and total extraperitoneal (TEP). TEP is less popular than the other approaches. We evaluated TEP's safety and effectiveness and compared different laparoscopic techniques. Methods: All patients with Spigelian hernia who had undergone extended TEP (eTEP) repair with mesh in our center from January 2007 to February 2020 were studied. A three‐port technique with a preperitoneal space created by telescope at the midline was adopted. A systematic review on laparoscopic mesh repair was performed by searching for "Spigelian hernia" and "laparoscopic" from 1999 to 2019 in the MEDLINE database. Results: Seven patients underwent eTEP repair for Spigelian hernia. Five presented with abdominal mass and underwent preoperative imaging. Two were diagnosed incidentally during TEP for inguinal hernia. The mean operative duration was 65 minutes (range, 40‐93 minutes). There were no open conversions or intraoperative complications. The mean length of hospital stay was 1.4 days (range, 1‐3 days). The mean follow‐up period was 44.3 months. One patient developed seroma. There was no recurrence or chronic pain. We identified 197 laparoscopic mesh repairs reported in 41 articles. IPOM (n = 91) was the most popular approach, followed by TAPP (n = 70) and TEP (n = 36). Laparoscopic mesh repair of Spigelian hernia is safe and offers excellent outcomes. Conclusion: We found the eTEP approach safe and effective for Spigelian hernia repair. IPOM, TAPP, and TEP are comparable. [ABSTRACT FROM AUTHOR]

The human sperm centrosome, comprising the two morphologically distinct centrioles and associated pericentriolar materials, plays a crucial role in fertilization and early embryonic development after fertilization. Once inside the oocyte, the sperm centrosome serves as a microtubule-organizing center, orchestrating mitotic spindle formation, chromosome segregation, and syngamy. Abnormalities of the sperm centrosome can lead to abnormal embryonic development and embryonic chromosomal instability, and are associated with pregnancy loss. Recent research has shed light on the molecular composition, regulation, and function of this vital organelle. Understanding the intricacies of the sperm centrosome is crucial for elucidating the mechanisms underlying successful fertilization and early embryonic development, as well as addressing infertility and developmental disorders associated with centrosomal defects. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Spigelian hernia (SH) is uncommon. Clinical diagnosis may be difficult, but computed tomography (CT) can help to establish the diagnosis. Laparoscopic repair is increasingly performed because it is associated with low morbidity rates. Laparoscopic approaches include transabdominal preperitoneal (TAPP), intraperitoneal onlay mesh (IPOM), and totally extraperitoneal (TEP). Here, we report our experiences of TEP repair for SH. Methods: A retrospective review was performed on all patients with SH who underwent elective laparoscopic TEP repair from 2007 to 2017 at Tung Wah Hospital, Hong Kong. Results: Four patients with SH were identified in the study period: three with a preoperative diagnosis of SH confirmed by CT scan and one diagnosed incidentally during TEP repair for inguinal hernia. The patients' mean age was 66.8 years (range, 55.0–82.0 years). The mean BMI was 22.8 kg/m2 (range, 20.8–23.6 kg/m2). The mean size of the SH defect was 2.0 cm (range, 0.5–3.0 cm). The mean operative time was 59 min (range, 40–86 min). Concomitant direct inguinal hernia was found in one patient and repaired simultaneously. All patients were discharged on postoperative day 1. One patient developed seroma, which subsided on conservative management. At a mean follow‐up of 36 months (range, 2–108 months), there was no recurrence. Conclusion: Laparoscopic repair for SH is preferred over the open approach as it is associated with a low morbidity rate and a short hospital stay. In our experience, TEP technique is safe and effective in laparoscopic SH repair. [ABSTRACT FROM AUTHOR]

Rods and cones are morphologically and developmentally distinct photoreceptor types with different functions in vision. Cones mediate daylight and color vision and in most mammals express M and S opsin photopigments for sensitivity to medium-long and short light wavelengths, respectively. Rods mediate dim light vision and express rhodopsin photopigment. The transcription factor networks that direct differentiation of each photoreceptor type are incompletely defined. Here, we report that Rorb-/- mice lacking retinoid-related orphan nuclear receptor β lose rods but overproduce primitive S cones that lack outer segments. The phenotype reflects pronounced plasticity between rod and cone lineages and resembles that described for Nrl-/- mice lacking neural retina leucine zipper factor. Rorb-/- mice lack NrI expression and reexpression of NrI in Rorb-/- mice converts cones to rod-like cells. Thus, Rorb directs rod development and does so at least in part by inducing the Nr!-mediated pathway of rod differentiation. [ABSTRACT FROM AUTHOR]

Abstract: Thyroid hormone (TH) has a remarkable range of actions in the development and function of the nervous system. A multigenic picture is emerging of the mechanisms that specify these diverse functions in target tissues. Distinct responses are mediated by α and β isoforms of TH receptor which act as ligand-regulated transcription factors. Receptor activity can be regulated at several levels including that of uptake of TH ligand and the activation or inactivation of ligand by deiodinase enzymes in target tissues. Processes under the control of TH range from learning and anxiety-like behaviour to sensory function. At the cellular level, TH controls events as diverse as axonal outgrowth, hippocampal synaptic activity and the patterning of opsin photopigments necessary for colour vision. Overall, TH coordinates this variety of events in both central and sensory systems to promote the function of the nervous system as a complete entity. [Copyright &y& Elsevier]

Background: Laparoscopic repair has been recommended as the method-of-choice of groin hernia repair among women. Whether the round ligament of uterus should be divided to facilitate mesh placement remains controversial. This study aims to review the outcomes of laparoscopic total extraperitoneal (TEP) groin hernia repair in women and to evaluate the impact of division of round ligament. Methods: Consecutive female patients with inguinal or femoral hernias who underwent elective laparoscopic TEP repair at a single institution from 2006 to 2017 were included for retrospective analysis. Primary outcomes were postoperative pain, genital prolapse, and recurrence. Outcomes of patients who had the round ligament divided were further compared with those with round ligament preserved and multivariable adjusted analysis was performed. Results: Sixty-eight patients with a total of 77 TEP repairs were included in the 12-year study period. The mean age was 45 ± 16 years old. Incidental femoral hernia was identified in 4 patients (5.9%). There was 1 (1.3%) recurrence upon mean follow-up of 42.9 ± 37.3 months. The round ligament was divided in 67.5% of patients, and upon multivariable adjusted analysis, there were no statistically significant differences in outcomes in terms of chronic pain (odds ratio [OR] = 2.210, P = .357), paresthesia (OR = 0.241, P = .149), and genital prolapse (OR = 0.327, P = .415) when compared with patients with preserved round ligament. Conclusion: Laparoscopic groin hernia repair in women is associated with low recurrence. Division of round ligament intraoperatively facilitates mesh placement and has minimal impact on clinical outcomes. [ABSTRACT FROM AUTHOR]

Introduction: The advantages of laparoscopic surgery for ventral hernia repairs are well documented, but its application for small paraumbilical hernias has been less studied. There is no consensus regarding the best technique. Methods: All patients who had open (suture or mesh) and laparoscopic repair of primary paraumbilical hernia between September 2007 and September 2017 in a single center were identified. Hernial defects of 2 cm or less were included; recurrent hernias were excluded. Primary outcomes included operative time, length of hospital stay, and surgical complications. Results: Seventy‐seven patients were recruited: 54 (70.1%) had open repair and 23 (29.9%) had laparoscopic repair. Forty‐six patients (85%) in the open group had primary suture repair. The mean operative time was significantly shorter in the open group than in the laparoscopic group (27.2 vs 56.1 min, P < 0.05). The length of hospital stay in the open group was significantly shorter than in the laparoscopic group (0.8 vs 1.4 days, P = 0.00). Early complications rates were similar, with wound complications in 5.6% (3/54) of open repair patients and 4.3% (1/23) of laparoscopic repair patients (P = 1.0). Among open repair patients, 19 patients (35.2%) were successfully discharged within 12 h after operation. Two patients (3.7%) in the open simple suture group developed recurrence, but no recurrence was identified in the laparoscopic group; this was not statistically significant (P = 1.0). Conclusion: The laparoscopic approach is comparable to the open approach in the repair of small paraumbilical hernias. For small paraumbilical hernias, we recommend that laparoscopic repair be reserved for obese patients or those with suspected multiple hernial defects. [ABSTRACT FROM AUTHOR]

Abstract Purpose The emergence of antiseptic resistance and/or antiseptic-resistance genes in methicillin-resistant Staphylococcus aureus (MRSA) may result in failure of decolonization treatments. Plasmid-encoded efflux pump genes qacA/B and qacC (smr) confer tolerance to chlorhexidine and quaternary ammonium compounds. The objective of this study was to develop and validate a multiplex real time-PCR assay for detection of antiseptic-resistance genes, apply the assay on 200 MRSA isolates and explore if carriage of these genes was associated with resistance to topical antibiotics. Methodology A SYBR-Green based multiplex real time-PCR assay was developed to detect qacA/B , qacC , and mecA (internal control) simultaneously. The multiplex assay was compared against conventional single-plex PCR followed by agarose gel electrophoresis, using DNA from the first 73 MRSA isolates, followed by multiplex testing of the remaining 127 MRSA isolates. All 200 MRSA isolates were tested for susceptibility to mupirocin, retapamulin, neomycin, bacitracin and octenidine. The genetic diversity of the isolates was investigated by s pa -typing. Results The concordance between multiplex and conventional PCR, in assignments of qacA/B and qacC status were 99%(72/73) and 100%(73/73) respectively. Among 200 MRSA isolates, 48(24%) and 44(23%) were found to harbour qacA/B and qacC genes, respectively. These isolates remained susceptible to many common decolonization agents, except mupirocin. The predominant spa -types were t020 and t1081 (41 and 32 isolates respectively). Conclusion The real-time assay performed acceptably for the detection of qac genes. A high prevalence of antiseptic-resistance genes were detected in the MRSA isolates in our population and appeared to be associated with spa -type t1081. Highlights • High concordance of MRSA qac status between multiplex and conventional PCR • Qac-positive isolates remained susceptible to many common decolonization agents. • The predominant spa-types were t020 and t1081. • Findings have important implications in infection control and clinical management. [ABSTRACT FROM AUTHOR]

• Unexpected high prevalence of mcr-1 in stool specimens of patients attending a tertiary care hospital. • Variable antibioltic-susceptibility profiles of mcr-1 positive Enterobacteriaceae isolates. • No detection of mcr-1 positive carbapenem-resistant Enterobacteriaceae. • First report of the prevalence of human faecal carriage of mcr- 1 in Singapore. The aim of this study was to determine the prevalence of the colistin-resistance gene (mcr-1) and the antibiotic-susceptibility profile of mcr-1 positive, colistin-resistant isolates in stool specimens of patients attending a tertiary care hospital in Singapore. 201 diarrheal stool specimens of patients attending the Changi General Hospital between May to August 2017 were collected and screened for the presence of mcr-1 by culture and molecular methods. Antibiotic-susceptibility profile of mcr -1 positive isolates was determined using the polymyxin B and colistin E-tests and the VITEK 2 system. We observed an unexpectedly high prevalence of mcr-1 in patients attending a tertiary care hospital in Singapore, i.e 6.0% and 8.0% estimated by stool culture and direct stool PCR, respectively. The mcr-1 gene was detected predominantly in Escherichia coli. Antibiotic-susceptibility testing on 12 mcr-1 positive Enterobacteriaceae isolates revealed variable susceptibility profiles with no detection of carbapenem-resistant Enterobacteriaceae. This is the first report of the prevalence of human faecal carriage of mcr- 1 in Singapore. Our findings highlight the potential risk of mcr- 1 spread among our patient cohort. The mcr-1 gene detection combined with the detection of other resistance gene targets of clinical importance is recommended to pre-empt the spread mcr-1 in our patients. [ABSTRACT FROM AUTHOR]

Acute gastroenteritis (AGE) is caused by a wide range of pathogens. Culture methods for the detection of bacterial pathogens is time consuming and labour intensive. This study compared a same-day-to-result commercial molecular method using BD Max™ Enteric Bacterial Panel against conventional culture and laboratory-developed PCR assays (LDTs), and characterised the epidemiology of bacterial AGE in Singapore. PCRs for Campylobacter spp., Salmonella spp., Shigella spp./Enteroinvasive Escherichia coli (EIEC) and Shiga toxin-producing E. coli (STEC)/ Shigella dysenteriae were performed on the BD Max™ platform. Concurrent routine bacterial culture ("reference standard") was performed for Campylobacter , Salmonella , Shigella , Vibrio and Aeromonas spp. In the event of a discrepancy, an "expanded reference standard" (bacterial culture with LDT) was used. There were 299 stool specimens in the study, with no bacterial pathogens detected in 190 samples (63.5%). The positive samples (n = 109,36.5%) were detected with Salmonella (n = 57,19.1%), Campylobacter (n = 28,9.4%), Vibrio parahaemolyticus (n = 6,2.0%), Shigella /EIEC (n = 6,2.0%), ETEC (n = 4,1.3%), STEC (n = 2,0.7%), Aeromonas (n = 2,0.7%), Plesiomonas shigelloides (n = 1,0.3%) and 3(1.0%) co-infections. Compared to the "expanded reference standard", conventional culture missed 38/112 (33.9%) pathogens. Conversely, testing by BD Max™ alone failed to detect 17 pathogens. BD Max™ reported seven (2.3%) false-positive results. BD Max™ increased the detection rate of bacterial AGE pathogens in the panel, but was limited by the absence of detection capability for Vibrio and Aeromonas spp. • Acute gastroenteritis (AGE) is caused by a wide range of pathogens. • Culture methods for bacterial detection are time-consuming and labour intensive. • BD Max™ Enteric Bacterial Panel increases detection yield with shorter turnaround. • Combination of culture for Vibrio and Aeromonas with BD Max™ usage is recommended. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to determine the effect of Akt gene ablation on Akt/Forkhead Box O (FOXO) signaling and atrogene expression. This was accomplished by studying wild-type (WT) and isoform-specific Akt knockout (Akt1-/- and Akt2-/-) mice. The ability of insulin to promote Akt phosphorylation on Ser473 was significantly lower in extensor digitorum longus (EDL) and soleus muscles from Akt1-/- and Akt2-/- mice compared with WT mice. Total Akt1 protein levels were significantly lower in EDL muscles of Akt2-/- mice compared with WT mice, a process that appears to be posttranscriptionally regulated as Akt1 mRNA levels were unchanged. The loss of Akt1 protein in EDL muscles of Akt2-/- mice does not appear to be due to insulin resistance because 4 mo of a high-fat diet failed to reduce Akt1 protein levels in muscles of WT mice. Although FOXO3a phosphorylation and atrogin-1 expression were unaltered in muscles of Akt1-/- and Akt2-/- mice, the expression of the atrogenes Bnip3 and gabarapl were significantly elevated in muscles of both Akt1 and Akt2 knockout mice. Finally, the expression of striated activator of Rho signaling was significantly increased in muscles of Akt2-/- mice compared with Akt1-/- and WT mice. Our results demonstrate that the ablation of Akt isoforms disassociates insulin action and Akt/ FOXO signaling to atrogenes. [ABSTRACT FROM AUTHOR]

Summary [ABSTRACT FROM AUTHOR]

Clavulanic acid is a potent mechanism-based inhibitor of TEM-1 and SHV-1 β-lactamases, enzymes that confer resistance to β-1actams in many Gram-negative pathogens. This compound has enjoyed widespread clinical use as part of β-lactam β-1actamase inhibitor therapy directed against penicillin-resistant pathogens. Unfortunately, the emergence of clavulanic acid-resistant variants of TEM-1 and SHV-1 β-lactamase significantly compromise the efficacy of this combination. A single amino acid change at Ambler position Ser130 (Ser ↵ Gly) results in resistance to inactivation by clavulanate in the SHV-1 and TEM-1 β-lactamases. Herein, we investigated the inactivation of SHV-1 and the inhibitor-resistant S130G variant β-lactamases by clavulanate. Using liquid chromatography electrospray ionization mass spectrometry, we detected multiple modified proteins when SHV-1 β-lactamase is inactivated by clavulanate. Matrix-assisted laser desorption ionization-time of flight mass spectrometry was used to study tryptic digests of SHV-1 and S130G β-lactamases (± inactivation with clavulanate) and identified peptides modified at the active site Ser70. Ultraviolet (UV) difference spectral studies comparing SHV-1 and S130Gβ-1actanmses inactivated by clavulanate showed that the formation of reaction intermediates with absorption maxima at 227 and 280 mn are diminished and delayed when S130G β-1actamase is inactivated. We conclude that the clavulanic acid inhibition of the S130G variant β-lactamase must follow a branch of the normal inactivation pathway. These findings highlight the importance of understanding the intermediates formed in the inactivation process of inhibitor-resistant β-1actamases and suggest how strategic chemical design can lead to novel ways to inhibit β-lactamases. [ABSTRACT FROM AUTHOR]

Weak protein-protein interactions (PPIs) (KD > 10-6 M) are critical determinants of many biological processes. However, in contrast to a large growing number of well-characterized, strong PPIs, the weak PPIs, especially those with KD > 10-4 M, are poorly explored. Genome wide, there exist few 3D structures of weak PPIs with KD > 10-4 M, and none with KD > 10-3 M. Here, we report the NMR structure of an extremely weak focal adhesion complex (KD∼3 × 10-3 M) between Nck-2 SH3 domain and PINCH-1 LIM4 domain. The structure exhibits a remarkably small and polar interface with distinct binding modes for both SH3 and LIM domains. Such an interface suggests a transient Nck-2/PINCH-1 association process that may trigger rapid focal adhesion turnover during integrin signaling. Genetic rescue experiments demonstrate that this interface is indeed involved in mediating cell shape change and migration. Together, the data provide a molecular basis for an ultraweak PPI in regulating focal adhesion dynamics during integrin signaling. [Copyright &y& Elsevier]

Generation of a strong electrical potential in the cochlea is uniquely mammalian and may reflect recent evolutionary advances in cellular voltage-dependent amplifiers. This endocochlear potential is hypothesized to dramatically improve hearing sensitivity, a concept that is difficult to explore experimentally, because manipulating cochlear function frequently causes rapid degenerative changes early in development. Here, we examine the deafness phenotype in adult Claudin 11-null mice, which lack the basal cell tight junctions that give rise to the intrastrial compartment and find little evidence of cochlear pathology. Potassium ion recycling is normal in these mutants, but endocochlear potentials were below 30 mV and hearing thresholds were elevated 50 dB sound pressure level across the frequency spectrum. Together, these data demonstrate the central importance of basal cell tight junctions in the stria vascularis and directly verify the two-cell hypothesis for generation of endocochlear potential. Furthermore, these data indicate that endocochlear potential is an essential component of the power source for the mammalian cochlear amplifier. [ABSTRACT FROM AUTHOR]

The increasing number of bacteria resistant to combinations of β-lactam and β-lactamase inhibitors is creating great difficulties in the treatment of serious hospital-acquired infections. Understanding the mechanisms and structured basis for the inactivation of these inhibitor-resistant β-lactamases provides a rationale for the design of novel compounds. In the present work, SHV-1 and the Ser130 → Gly inhibitor-resistant variant of SHV-1 β-lactamase were inactivated with tazobactam, a potent class A β-lactamase inhibitor. Apoenzymes and inhibited β-lactamases were analyzed by liquid chromatography-electrospray ionization mass spectrometry (LC-ESI/ MS), digested with trypsin, and the products resolved using LC-ESI/MS and matrix-assisted laser desorption ionization-time of flight mass spectrometry. The mass increases observed for SHV-1 and Ser130 → Gly (+ Δ 88 Da and + Δ 70 Da, respectively) suggest that fragmentation of tazobactam readily occurs in the inhibitor-resistant variant to yield an inactive β-lactamase. These two mass increments are consistent with the formation of an aldehyde (+ Δ 70 Da) and a hydrated aldehyde (+ Δ 88 Da) as stable products of inhibition. Our results reveal that the Ser → Gly substitution at amino acid position 130 is not essential for enzyme inactivation. By examining the inhibitor-resistant Ser130 → Gly β-lactamase, our data are the first to show that tazobactam undergoes fragmentation while still attached to the active site Ser70 in this enzyme. After acylation of tazobactam by Ser130 → Gly, inactivation proceeds independent of any additional covalent interactions. [ABSTRACT FROM AUTHOR]

The precise movement of the cochlear basilar membrane (BM) stimulates the sensory hair cells during auditory transduction. However, the molecular composition of the BM that confers its specialized properties of support and elasticity is poorly understood. A differential screen of cochlear RNA from deaf mice lacking thyroid hormone receptor β was used to identify a sequence encoding a secreted protein, which is abundant in the BM and is expressed at low levels in the heart, lung, and brain. The protein possesses several domains for protein interactions and is related to emilin (elastin microfibril interface-located protein) previously isolated from aorta. This cochlear emilin-2 mRNA is expressed in the tympanic border cells underlying the BM and an antibody detected protein in the extracellular matrix surrounding the collagenous fibers in the BM. These results identify emilin-2 as a major BM component and suggest that it contributes to the developmental assembly or function of the BM. [Copyright &y& Elsevier]

Abstract: This study evaluated the phenotypic string test for identifying Klebsiella pneumoniae bacteraemic isolates associated with primary liver abscess. Test reproducibility and repeatability exceeded 95%, with varying sensitivity (66–90%) and specificity (64–67%) depending on cut-off values. The positive predictive value of a positive string test for identifying hepato-virulent isolates was <35%. [Copyright &y& Elsevier]