Use of mouse primary epidermal organoids for USA300 infection modeling and drug screening.

Skin infections caused by drug-resistant Staphylococcus aureus occur at high rates nationwide. Mouse primary epidermal organoids (mPEOs) possess stratified histological and morphological characteristics of epidermis and are highly similar to their derived tissue at the transcriptomic and proteomic levels. Herein, the susceptibility of mPEOs to methicillin-resistant S. aureus USA300 infection was investigated. The results show that mPEOs support USA300 colonization and invasion, exhibiting swollen epithelial squamous cells with nuclear necrosis and secreting inflammatory factors such as IL-1ß. Meanwhile mPEOs beneficial to observe the process of USA300 colonization with increasing infection time, and USA300 induces mPEOs to undergo pyroptosis and autophagy. In addition, we performed a drug screen for the mPEO infection model and showed that vancomycin restores cell viability and inhibits bacterial internalization in a concentration-dependent manner. In conclusion, we establish an in vitro skin infection model that contributes to the examination of drug screening strategies and antimicrobial drug mechanisms.

[Corrigendum] Alterations in gene expression during sexual differentiation in androgen receptor knockout mice induced by environmental endocrine disruptors.

Following the publication of the above article, an interested reader drew to our attention a number of issues and concerns related to the descriptions of the genes and mouse models in the above paper. After having consulted with the authors, they have acknowledged that their paper did indeed contain a number of errors, and these are listed below in this Corrigendum. First, the authors realized that an incorrect figure was included as Fig. 1 in the paper. The correct (and entirely different) version of Fig. 1, together with its figure legend, is shown opposite. The following textual errors in the paper should also be noted: i) In the Abstract, lines 3­4 in the left­hand column (LHC): "androgen receptor (AR)­/­, AR+/­ and AR+/+ male mice" should have been written as "androgen receptor (AR) conditional knockout mice"; line 5 in the LHC: "flox­AR" should have been written as "ARflox/+"; line 6 in the LHC: "AR­Cre" should have been written as "Amhr2­Cre"; line 22 in the LHC: "AR+/­" should have been written as "ARflox/Y"; line 1 in the right­hand column (RHC): "heterozygous" should have been written as "ARflox/Y"; and line 2 in the RHC, "heterozygous" should have been written as "ARflox/Y Cre+". ii) In the Introduction, paragraph 3, lines 6­7 in the LHC: "or female ARKO mice" should have been deleted; paragraph 4, line 5 in the LHC: "AR­/­", "AR+/­" and "AR+/+" should have been deleted; paragraph 4, line 11 in the LHC: "AR­/­", and "AR+/­" should have been written as "AR­/Y", whereas "AR+/+" should have been written as "AR+/Y". iii) In the Materials and methods, paragraph 3, the last sentence in the RHC {"The identification of the plasmid containing leydig cells expressing Cre recombinant enzyme and the specificity of the genetically modified (gm) sequence [Amhr2­Cre (7.1)] are shown in Fig. 1} should have been written as "The positive clones were identified by digestion and sequencing." iv) In the Results, the first subheading in the RHC ("...transgenic mouse model (Amhr2­Cre)" should have been written as "...AR conditional knockout targeting vector"; paragraph 1, lines 1­3 in the RHC: The sentence "The AR gene condition knockout plasmid was identified and confirmed by enzyme digestion with BamHI" should have been written as "The AR gene conditional knockout strategy is shown in Fig. 1. The gene targeting vector was identified and confirmed by enzyme digestion with BamHI"; paragraph 1, line 4 in the RHC: "2.7 kb" should have been written as "7.8 kb"; Table III, in the title and in the Table heading, "AR+/­" should have been written as "AR+/Y", and "AR­/­" should have been written as "AR­/Y"; in the subheading "Comparison between AR­/­ male mice and normal mice", "AR­/­" should have been written as "AR­/Y", and "normal" should have been written as "AR+/Y"; and paragraph 4, lines 3­5 in the LHC: "AR+/­" should have been written as "AR+/Y", and "AR­/­" should have been written as "AR­/Y". All the authors thank the interested reader for drawing these matters to their attention, and agree to the contents of this Corrigendum. The authors also stress that these errors did not significantly influence either the results or the conclusions of the paper. Furthermore, the authors apologize to the Editor of International Journal of Molecular Medicine and to the readership for any inconvenience caused. [the original article was published in International Journal of Molecular Medicine 35: 399­404, 2015; DOI: 10.3892/ijmm.2014.2015].

[Corrigendum] Alterations in gene expression during sexual differentiation in androgen receptor knockout mice induced by environmental endocrine disruptors.

Following the publication of this article, the authors noticed the following error: In the Abstract, the full name of DBP should be dibutyl phthalate and not D binding protein. The same error was observed on the second page of the manuscript (second line on right column), where the full name of DBP should be dibutyl phthalate and not D binding protein. [the original article was published in the International Journal of Molecular Medicine 35: 399-404, 2015 DOI: 10.3892/ijmm.2014.2015].

Alterations in gene expression during sexual differentiation in androgen receptor knockout mice induced by environmental endocrine disruptors.

In the present study, we aimed to explore the effect of environmental endocrine disruptors (EEDs) on sexual differentiation in androgen receptor (AR)-/-, AR+/- and AR+/+ male mice. By using a Cre-loxP conditional knockout strategy, we generated AR knockout mice. By mating flox-AR female mice with AR-Cre male mice, the offspring male mice which were produced were examined. Mice not subjected to any type of intervention were used as the controls. Furthermore, male mice of different genotypes were selected and further divided into subgroups as follows: the control group, bisphenol A (BPA) group and the dibutyl phthalate [corrected] (DBP) group. The expression of the Wilms tumor 1 (WT1), lutropin/choriogonadotropin receptor (LHR), 17-ß-hydroxysteroid dehydrogenase type 3 (17ßHSD3) and steroid-5-alpha-reductase, alpha polypeptide 2 (SRD5A2) genes was determined by RT-qPCR and western blot analysis. There was no statistically significant difference in the weight of the mice between the control group and the knockout group (P>0.05). The results revealed that, compared with the control group, in the knockout group, anogenital distance was shortened, and testicular weight and testosterone levels were decreased; estradiol levels were elevated; the differences were statistically significant (P<0.05). In the group of AR+/- male mice exposed to 100 mg/l EEDs, hypospadias was successfully induced, suggesting that EEDs are involved in the embryonic stage of sexual development in male mice. The quantitative detection of WT1, LHR, 17ßHSD3 and SRD5A2 gene expression by RT-qPCR and western blot analysis indicated that these genes were significantly downregulated in the mice in the BPA group. In conclusion, exposure to EEDs induces hypospadias in heterozygous and wild-type male mice offspring during sexual differentiation, but has no effect on homozygous offspring. Therefore, EEDs play an important role during the third stage of sexual differentiation.

Subtrochanteric valgus osteotomy with monolateral external fixator in hips for patients with severe cerebral palsy.

Subtrochanteric valgus osteotomy has been used for painful hip joint dislocation in patients with severe cerebral palsy. The goal of this study was to evaluate 11 patients (17 hips) with severe cerebral palsy who had chronically dislocated and painful hips treated with subtrochanteric valgus osteotomy using a monolateral external fixator. A retrospective review was performed of 11 patients (average age, 17.8 years) with severe quadriplegic cerebral palsy with flexion-adduction contractures due to chronically dislocated and painful hips. A subtrochanteric valgus osteotomy with a monolateral fixator was performed in all patients. Patients were analyzed clinicoradiologically, and caregivers were asked about ease of handling, transfers, and perineal care. At an average follow-up of 37 months (range, 14-72 months), all caregivers were satisfied with the surgery and felt that their child was more comfortable and could sit with support for a longer time period and that perineal care, wheelchair mobilization, and transfers were much easier. A total of 11 complications in 7 patients were observed, including pin-tract infections, delayed consolidation, abduction deformity, and hypostatic pneumonia. The complication rate of subtrochanteric valgus osteotomy was comparable with other methods, and this method had the advantage of shorter surgical time, ease of application, no internal implant with lesser chance of infection or heterotopic calcification, and less intraoperative blood loss with less morbidity.

Pelvic support osteotomy for unstable hips using hybrid external fixator: case series and review of literature.

BACKGROUND: Instability of the hip joint is a source of great discomfort to the patient due to pain, limp and leg-length discrepancy. Pelvic support osteotomy with Ilizarov hip reconstruction, along with its various modifications, has emerged as a standard treatment modality for this difficult problem. We present a series of patients with unstable hips treated with a modification of the monolateral fixator-the hybrid external fixator. MATERIALS AND METHODS: A retrospective review of a series of 23 patients (38 hips) with unstable hips treated at our institute with the hybrid external fixator was performed. The mean age of the patients was 19.1 years (range 7-49 years). The outcomes were evaluated radiologically and clinically using the Harris hip score. RESULTS: After a mean follow-up period of 30.5 months (range 10-91 months), the range of motion of the hip had improved, pain had decreased, and the Harris hip score had improved from 63.43 to 75.17, which was statistically significant. The pre-operative knee range of motion was achieved in all patients by the last follow-up. Trendelenburg gait disappeared in all patients except for 3, limb length discrepancy improved from a pre-operative mean of 43 mm to a post-operative mean of 5 mm at final follow-up, and the mechanical axis was regained in all patients. Pin-tract infections were the commonest complications, occurring in 12 patients (52%). CONCLUSIONS: This study shows that pelvic support osteotomy using the new hybrid external fixator, which combines the versatility and modularity of the Ilizarov frame with the compactness of the monolateral fixator, is a useful treatment modality in individuals with unstable hips.