Biofilm formation and presence of icaAD gene in clinical isolates of staphylococci

In view of the significant negative impact of biofilm mediated infection on patient health and the necessity of a reliable phenotypic method for detecting biofilm producers, this study aimed to determine biofilm producing ability and presence of icaAD gene in clinical staphylococcal isolates as well as to assess the reliability of two phenotypic methods used for detection of biofilm. A total of 50 staphylococcal strains were isolated from 124 clinical specimen (94 intravascular catheters and 30 blood samples) collected from in-patients at Pediatric Hospital of Ain Shams University. Two phenotypic methods were used for detection of biofilm production; qualitative Congo red agar (CRA) and quantitative Microtiter plate (MTP). PCR was used to determine the presence of icaAD gene. Biofilm production was detected in 23(46%) isolates by CRA and MTP, however, both methods correlated only in 10(20%) of isolates. The icaAD gene was detected in 16(32%) staphylococcal isolates. Correlating phenotypic methods with icaAD gene detection, only 8(50%) of the icaAD positive staphylococci were positive by MTP, while 5(31%) were positive by CRA method. Unexpectedly, 15(30%) and 18 (36%) of the isolates were icaAD negative while MTP and CRA positive, respectively. In conclusion, despite the presence of icaAD gene, it does not always correlate with in vitro biofilm formation. The biofilm-forming ability of some isolates in absence of icaAD gene highlights the importance of further genetic investigations of ica independent biofilm formation mechanisms. Comparing phenotypic methods, MTP remains a better tool for biofilm screening.Keywords: Staphylococci; Biofilm; Congo red agar; Microtiter plate; icaAD gen

Glucocorticoid Receptors and the Pattern of Steroid Response in Idiopathic Nephrotic Syndrome

Introduction: Little is known about the relationships between the T lymphocytes (CD3+) expression of glucocorticoid receptors (GCR) and the response to glucocorticoid treatment in children with idiopathic nephrotic syndrome (NS). The aim of the current study is to determine whether steroid responsiveness is dependent on the amount of T lymphocytes GCR expressionMethods: We studied 60 children with idiopathic NS in the age group from 2-10 years. According to the response to steroids we classified our patients into early responders (ER; n=46) and late responders (LR; n=14). Sixty age and gender matched healthy children represented the control group. The clinical and laboratory findings at baseline and GCR expression by T lymphocytes (CD3+) as determined by flow cytometry were compared between the three groups.Results: The T lymphocytes (CD3+) expression of GCR was significantly lower in the LR than that in the control group (P<0.01), whereas it was similar in the ER and control groups. GCR expression was also decreased in the LR group compared to the ER group (P<0.01). Furthermore, the T lymphocytes (CD3+) expression of GCR correlated inversely with the time to complete remission (CR) (r = -0.54, P<0.05), but not with urinary protein excretion at baseline.Conclusion: The levels of T lymphocytes (CD3+) expression of GCR may be a useful predictor of steroid responsiveness in children presenting with idiopathic NS

Prospective evaluation of the impact of post-cesarean section uterine scarification in the perinatal diagnosis of placenta accreta spectrum

Objective: Standardized ultrasound imaging and pathology protocols have recently been developed for the perinatal diagnosis of placenta accreta spectrum (PAS) disorders. The aim of this study was to evaluate prospectively the effectiveness of these standardized protocols in the prenatal diagnosis and postnatal examination of women presenting with a low-lying placenta or placenta previa and a history of multiple Cesarean deliveries (CDs). Methods: This was a prospective cohort study of 84 consecutive women with a history of two or more prior CDs presenting with a singleton pregnancy and low-lying placenta/placenta previa at 32–37 weeks' gestation, who were referred for perinatal care and management between 15 January 2019 and 15 December 2020. All women were investigated using the standardized description of ultrasound signs of PAS proposed by the European Working Group on abnormally invasive placenta. In all cases, the ultrasound features were compared with intraoperative and histopathological findings. Areas of abnormal placental attachment were identified during the immediate postoperative gross examination and sampled for histological examination. The data of a subgroup of 32 women diagnosed antenatally as non-PAS who had complete placental separation at birth were compared with those of 39 cases diagnosed antenatally as having PAS disorder that was confirmed by histopathology at delivery. Results: Of the 84 women included in the study, 42 (50.0%) were diagnosed prenatally as PAS and the remaining 42 (50.0%) as non-PAS on ultrasound examination. Intraoperatively, 66 (78.6%) women presented with a large or extended area of dehiscence and 52 (61.9%) with a dense tangled bed of vessels or multiple vessels running laterally and craniocaudally in the uterine serosa. A loss of clear zone was recorded on grayscale ultrasound imaging in all 84 cases, while there was no case with bladder-wall interruption or with a focal exophytic mass. Myometrial thinning (< 1 mm) in at least one area of the anterior uterine wall was found in 41 (97.6%) of the 42 cases diagnosed as non-PAS on ultrasound and 37 (88.1%) of the 42 diagnosed antenatally as PAS. Histological samples were available for all 48 hysterectomy specimens with abnormal placental attachment and for the three cases managed conservatively with focal myometrial resection and uterine reconstruction. Villous tissue was found directly attached to the superficial myometrium (placenta creta) in six of these cases and both creta villous tissue and deeply implanted villous tissue within the uterine wall (placenta increta) were found in the remaining 45 cases. There was no evidence of percreta placentation on histology in any of the PAS cases. Comparison of the main antenatal ultrasound signs and perioperative macroscopic findings between the two subgroups correctly diagnosed antenatally (32 non-PAS and 39 PAS) showed no significant difference with respect to the distribution of myometrial thinning and the presence of a placental bulge on ultrasound and of anterior uterine wall dehiscence intraoperatively. Compared with the non-PAS subgroup, the PAS subgroup showed significantly higher placental lacunae grade (P < 0.001) and more often hypervascularity of the uterovesical/subplacental area (P < 0.001), presence of bridging vessels (P = 0.027) and presence of lacunae feeder vessels (P < 0.001) on ultrasound examination, and increased vascularization of the anterior uterine wall intraoperatively (P < 0.001). Conclusions: Remodeling of the lower uterine segment following CD scarring leads to structural abnormalities of the uterine contour on both ultrasound examination and intraoperatively, independently of the presence of accreta villous tissue on microscopic examination. These anatomical changes are often reported as diagnostic of placenta percreta, including cases with no histological evidence of PAS. Guided histological examination could improve the overall diagnosis of PAS and is essential to obtain evidence-based epidemiologic data. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology

Assessment of ultrasound features of placenta accreta spectrum in women at high risk: association with outcome and interobserver concordance

OBJECTIVES: The aims of this study were to evaluate the prenatal ultrasound features associated with operative complications and to assess the interobserver agreement in a cohort with detailed intraoperative and histopathologic data. METHODS: We conducted a retrospective, multicentre cohort study of 102 patients at high-risk of placenta accreta spectrum (PAS) between January 2019 and May 2022. De-identified ultrasound images were reviewed retrospectively and independently by two experienced operators blinded to clinical details, intra-operative features, outcome, and the histopathologic findings. The diagnosis of PAS was confirmed by the failure of detachment of one or more placental cotyledon from the uterine wall at delivery and the absence of decidua with distortion of the utero-placental interface by fibrinoid deposition on histologic examination of the accreta areas obtained by guided-sampling of partial myometrial resection or hysterectomy specimens. Antenatal categorisation was low or high probability of the likelihood of PAS at birth. Interobserver agreement was assessed using kappa statistic. Primary outcome was major operative morbidity (blood loss of ≥2000 ml, unintentional injury to the viscera, admission to intensive care unit or death). RESULTS: There were 66 cases with, and 36 cases without evidence PAS at birth. When blinded to other clinical details, the examiners agreed on the low or high probability of PAS in 87/102 cases (73.5%) on ultrasound features. The kappa statistic is 0.47 (95% CI: 0.28 - 0.66) showing moderate agreement. Morbidity was twice as common with a diagnosis of PAS. Concordant assessment of high probability of PAS was associated with the highest morbidity (66.6%) and a high (97.6%) chance of histopathological confirmation. CONCLUSIONS: The probability of histopathological confirmation is exceedingly high with concordant prenatal assessment suggestive of PAS. The interoperator agreement for preoperative assessment for histopathological confirmation of PAS is only moderate. Morbidity is linked to both histopathological diagnosis and antenatal assessment concordant of PAS. This article is protected by copyright. All rights reserved

A new methodologic approach for clinico-pathologic correlations in invasive placenta previa accreta

BACKGROUND: The development of new management strategies for women presenting with placenta accreta spectrum requires quality epidemiology data which have so far been limited by the high variability in clinical and histopathologic data confirming the diagnosis at birth. OBJECTIVE: To evaluate the role of a new methodologic approach for the correlation of clinical and pathological data for women with a history of prior cesarean delivery diagnosed prenatally with placenta previa accreta. STUDY DESIGN: A modified pathologic technique for gross examination of hysterectomy specimens with placenta in-situ consisting of intra-operative examination, immediate post-operative examination and guided histologic sampling was used prospectively in a cohort of 24 patients with singleton pregnancies complicated by placenta low-lying/placenta previa accreta. The maternal characteristics, detailed ultrasound findings, surgical outcomes and histopathologic examination were compared with those of a group of 24 patients with similar clinical characteristics where a standard pathologic examination method was used. RESULTS: The median reporting time for obtaining the complete histopathology results including the microscopic examination was significantly shorter (7 vs 15 days; P<0.001) and the median number of samples taken for histologic examination significantly lower (4 vs 14 samples; P<0.001) in the study group than in the controls. The number of histologic slides showing villous invasion was significantly higher (2 vs 1 slides; P=0.002) and the ratio of the number of samples taken to the numbers of slides confirming villous invasion was significantly lower (2 vs 9; P<0.001) in the study group than in the controls. In all cases of the study group, intra-operative examination identified a dense tangled bed of vessels or multiple vessels running laterally and cranio-caudally in the uterine serosa above the placental insertion which were no longer visible during immediate gross post-operative examination of the hysterectomy specimens. Immediate post-operative dissection enables the differential diagnosis between focal and large increta areas, and between abnormally adherent placenta and invasive placenta accreta. CONCLUSIONS: Valuable clinical information on the serosal vascularity, uterine dehiscence and extension of the accreta area is added with the description of the macroscopic examination during the surgical procedure and immediate dissection of the specimen. This methodological approach is cost-effective and increases the quality of the histologic sampling. It thus provides more accurate correlations with the clinical data and more accurate epidemiologic data collection. Perinatal pathologists should be part of multidisciplinary teams involved the management placenta accreta spectrum disorders

Assessment of ultrasound features of placenta accreta spectrum in women at high risk: association with outcome and interobserver concordance.

OBJECTIVES: To evaluate the prenatal ultrasound features associated with operative complications and to assess the interobserver agreement of prenatal ultrasound assessment with histopathologic confirmation of placenta accreta spectrum (PAS) in a cohort of high-risk patients with detailed intraoperative and histopathologic data. METHODS: This was a retrospective multicenter cohort study of patients at high risk of PAS referred for specialist perinatal care and management between January 2019 and May 2022. Deidentified ultrasound images were reviewed independently by two experienced operators blinded to clinical details, intraoperative features, outcome and histopathologic findings. The diagnosis of PAS was confirmed by failure of detachment of one or more placental cotyledons from the uterine wall at delivery, and the absence of decidua with distortion of the uteroplacental interface by fibrinoid deposition on histologic examination of the accretic areas obtained by guided sampling of partial myometrial resection or hysterectomy specimens. Patients were categorized as having a low or high likelihood of PAS at birth. Interobserver agreement of prenatal ultrasound assessment with histopathologic confirmation of PAS was assessed using the kappa statistic. Primary outcome was major operative morbidity (blood loss ≥ 2000 mL, unintentional injury to the viscera, admission to intensive care unit or death). RESULTS: A total of 102 women at high risk of PAS were referred, of whom 66 had evidence of PAS at birth and 36 did not. When blinded to other clinical details, the examiners agreed on the low or high probability of PAS, according to ultrasound features, in 75/102 cases (73.5%). The kappa statistic was 0.47 (95% CI, 0.28-0.66), showing moderate agreement. Morbidity was twice as common with concordant prenatal diagnosis of PAS vs concordant diagnosis of not PAS. Concordant assessment of high probability of PAS was associated with the highest morbidity (66.6%) and a very high (97.6%) likelihood of histopathologic confirmation. CONCLUSIONS: The probability of histopathologic confirmation is very high with concordant prenatal assessment suggestive of PAS. The interobserver agreement for preoperative assessment with histopathologic confirmation of PAS is only moderate. Morbidity is associated with both histopathologic diagnosis and concordant antenatal assessment of PAS. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology

Detection and Diagnosis of Stator and Rotor Electrical Faults for Three-Phase Induction Motor via Wavelet Energy Approach

This paper presents a fault detection method in three-phase induction motors using Wavelet Packet Transform (WPT). The proposed algorithm takes a frame of samples from the three-phase supply current of an induction motor. The three phase current samples are then combined to generate a single current signal by computing the Root Mean Square (RMS) value of the three phase current samples at each time stamp. The resulting current samples are then divided into windows of 64 samples. Each resulting window of samples is then processed separately. The proposed algorithm uses two methods to create window samples, which are called non-overlapping window samples and moving/overlapping window samples. Non-overlapping window samples are created by simply dividing the current samples into windows of 64 samples, while the moving window samples are generated by taking the first 64 current samples, and then the consequent moving window samples are generated by moving the window across the current samples by one sample each time. The new window of samples consists of the last 63 samples of the previous window and one new sample. The overlapping method reduces the fault detection time to a single sample accuracy. However, it is computationally more expensive than the non-overlapping method and requires more computer memory. The resulting window samples are separately processed as follows: The proposed algorithm performs two level WPT on each resulting window samples, dividing its coefficients into its four wavelet subbands. Information in wavelet high frequency subbands is then used for fault detection and activating the trip signal to disconnect the motor from the power supply. The proposed algorithm was first implemented in the MATLAB platform, and the Entropy power Energy (EE) of the high frequency WPT subbands’ coefficients was used to determine the condition of the motor. If the induction motor is faulty, the algorithm proceeds to identify the type of the fault. An empirical setup of the proposed system was then implemented, and the proposed algorithm condition was tested under real, where different faults were practically induced to the induction motor. Experimental results confirmed the effectiveness of the proposed technique. To generalize the proposed method, the experiment was repeated on different types of induction motors with different working ages and with different power ratings. Experimental results show that the capability of the proposed method is independent of the types of motors used and their ages