Structure and dynamics of chemically active ring polymers: swelling to collapse.

The ring structures are common in many synthetic or natural systems and experience both local and long-range forces by chemical sensing. This work is an effort to investigate the structural and dynamical properties of a chemically active ring in an explicit solvent bath utilizing hybrid molecular dynamics (MD) and multiparticle collision dynamics (MPCD) simulation techniques. We show that by tuning the chemical properties of the ring, it can be converted from a chemo-attractant to a chemo-repellent, thereby changing the steady state to be either collapsed or swelled as compared to its passive limit. We quantify these observations by comparing the scaling laws, local structures and the dynamics of active and passive rings. Furthermore, we show the impact of varying numbers of active sites by calculating the contact probability of the collapse state that highlights diverse structures. We also analyze the dynamics of the ring by finding the relaxation time and the mean square displacement of the centre of mass. A faster relaxation with enhanced diffusion is observed for the active rings.

Laparoscopic Management of Disseminated Peritoneal Leiomyomatosis.

STUDY OBJECTIVE: To show laparoscopic management of disseminated peritoneal leiomyomatosis (DPL). DESIGN: Stepwise demonstration of the technique with narrated video footage. SETTING: DPL is characterized by dissemination and proliferation of peritoneal and subperitoneal lesions primarily originating from smooth muscle cells [1]. Generally considered benign, cases of malignant transformation to leiomyosarcoma have been reported [2,3]. Iatrogenic DPL occurs because of unconfined morcellation resulting in small fragments of myoma that may implant on any organ and start deriving blood supply from it or may be pulled into port site while withdrawing laparoscopic cannulas [4]. It is estimated that the overall incidence of DPL after laparoscopic uncontained morcellation was 0.12% to 0.95% [5]. Mainstay of treatment is surgical resection of myomas and regular follow-up with imaging. A 28-year-old unmarried girl presented with complain of lump abdomen increasing in size for 1 year. She also complained of a 15 kg weight loss in the last 1 year; 4 years ago, patient had undergone laparoscopic myomectomy with unconfined morcellation for a 10 × 8 cm cervical myoma. Presently her menses were regular with a 28-day cycle and 3 to 4 days' average flow. Magnetic resonance imaging showed multiple nodular lesions of varying sizes in relation to small bowel, colon, uterus, and anterior abdominal wall  suggestive of DPL. Bilateral ovaries were normal. Tumor markers were as follows: CA 125 23.2 (<35) U/mL Carcinoembryonic antigen 1.67 (<8) ng/mL CA 19-9 47 (<37) U/mL Lactate dehydrogenase 809 (180-360) IU/L Alpha-fetoprotein 2.03 (<10) ng/mL Beta human chorionic gonadotropin 1.2(<2) mIU/mL Tru-cut biopsy was done elsewhere to rule out peritoneal carcinomatosis in view of raised CA 19-9 and lactate dehydrogenase, history of weight loss, and imaging showing multiple abdominal masses. Histopathological examination showed leiomyomatosis and immunohistochemistry for smooth muscle actin, desmin, and vimentin were positive. INTERVENTIONS: On laparoscopy the abdominal cavity was found studded with multiple leiomyomas of varying sizes deriving blood supply from ilium, transverse, descending and sigmoid colon, rectum, left tube, left ovary, pouch of Douglas, bilateral uterosacrals, uterovesical fold, and anterior abdominal wall. Large blood vessels were seen traversing between the descending and sigmoid colon and the myomas. Principles of surgery were as follows: 1. Complete removal of myomas 2. Cauterization of blood vessels feeding the parasitic myomas to minimize blood loss 3. Disscetion abutting the myoma to prevent injury to adjacent viscera. A total of 26 myomas were removed. All the myomas were retrieved by morcellation in a bag. Histopathology confirmed the diagnosis of diffuse peritoneal leiomyomatosis. Follow-up ultrasound at 6 months showed no recurrence of leiomyomatosis. CONCLUSION: Proper mapping of lesions and surgery for complete removal of all masses is the mainstay of treatment. Contained morcellation in bag should be the norm to prevent iatrogenic DPL. Regular follow-up with imaging is required to rule out recurrence.

Laparoscopic Management of Partial Molar Caesarean Scar Ectopic Pregnancy.

STUDY OBJECTIVE: To demonstrate laparoscopic management of a molar scar ectopic pregnancy. DESIGN: Stepwise demonstration of the technique with narrated video footage. SETTING: Cesarean scar ectopic pregnancy and molar pregnancy are 2 separate extremely rare pathologies with an incidence range from 1/1800 to 1/2500 of all pregnancies for the former [1,2]. The concurrence of both cesarean scar ectopic and molar pregnancy is furthermore exceptionally rare, and there are only 8 reported cases of cesarean scar molar pregnancy in literature till date [3]. There is a high risk of uterine rupture, uncontrolled hemorrhage, hysterectomy, and significant maternal morbidity owing to thin myometrium and fibrous scar after cesarean section [4,5]. Knowledge and awareness about this clinical condition aid in early diagnosis and reduced morbidity. Here, we present a rare case of cesarean scar ectopic pregnancy that was operated for failed medical management and diagnosed to be molar scar ectopic pregnancy intraoperatively. INTERVENTIONS: Total laparoscopic approach to molar scar ectopic pregnancy excision involved the following steps, strategies to minimize blood loss, and complete enucleation of tissue: (1) Hysteroscopy to localize the scar ectopic and its type and size (2) Bladder dissection to expose scar (3) Intramyometrial injection of vasopressin (4) Use of harmonic scalpel to delineate the gestational sac (5) Complete evacuation of products of conception (6) Excision of scar tissue (7) Uterine repair in 2 layers CONCLUSION: There are only 8 reported cases of cesarean scar molar pregnancy in literature till date, and all patients had at least 2 previous uterine curettages with abnormally increased ß-hCG levels. The clinical manifestations were varied, the most common symptom being vaginal bleeding for a period >1 month, including our case [3]. Considering the limitations of ultrasound, magnetic resonance imaging, and serum hCG levels in the differential diagnosis of molar cesarean scar pregnancy from normal cesarean scar pregnancy, postoperative specimen should be sent for histologic examination [6]. As seen in our case, the possibility of molar pregnancy at cesarean scar ectopic site should be kept in mind in cases with rising ß-hCG levels despite continuous medical interventions, which was being medically managed for 3 months. Our case is the first to be successfully managed with laparoscopic surgery as the previously reported cases were managed with suction evacuation, chemotherapy, laparotomy, or hysterectomy [3].

A Randomized Trial on the Efficacy of Mastery Learning for Primary Care Provider Melanoma Opportunistic Screening Skills and Practice.

BACKGROUND: Early detection of melanoma represents an opportunity to reduce the burden of disease among people at increased risk for melanoma. OBJECTIVE: To develop and demonstrate the efficacy of online training. DESIGN: Randomized educational trial. PARTICIPANTS: Primary care providers (PCPs). INTERVENTION: Mastery learning course with visual and dermoscopic assessment, diagnosis and management, and deliberate practice with feedback to reach a minimum passing standard. MAIN MEASURES: Pre-test/post-test diagnostic accuracy. Referral of concerning lesions for 3 months before and after the educational intervention. KEY RESULTS: Among the 89 PCPs, 89.8% were internal medicine physicians, and the remainder were physician assistants embedded in internists' practices. There were no differences between control and intervention groups regarding gender, age, race, or percentage of full-time PCPs. The control group had more PCPs who reported less than 5 years of practice (n = 18) than the intervention group (n = 6) (χ2 [6, n = 89] = 14.34, p = 0.03). PCPs in the intervention group answered more melanoma detection questions correctly on the post-test (M = 10.05, SE = 1.24) compared to control group PCPs (M = 7.11, SE = 0.24), and had fewer false-positive and no false-negative melanoma diagnoses (intervention, M = 1.09, SE = 0. 20; control, M = 3.1, SE = 0.23; ANCOVA, F[1,378] =27.86, p < 0.001; ηp2 = 0.26). PCPs who underwent training referred fewer benign lesions, including nevi, seborrheic keratoses, and dermatofibromas, than control PCPs (F[1,79] = 72.89, p < 0.001; ηp2 = 0.489; F[1,79] = 25.82, p < 0.001; ηp2 = 0.246; F[1,79] = 34.25, p < 0.001; ηp2 = 0.302; respectively). Those receiving training referred significantly more melanomas than controls (F[1,79] = 24.38, p < 0.001; ηp2 = 0.236). Referred melanomas (0.8 ± 0.07 per month for intervention, 0.17 ± 0.06 for control) were mostly located on the head and neck. CONCLUSIONS: Mastery learning improved PCPs' ability to detect melanoma on a standardized post-test and may improve referral of patients with suspected melanoma. Further studies are needed to confirm this finding. ClinicalTrials.gov NCT02385253.

Massive spontaneous intraperitoneal hemorrhage in a young female with chronic immune thrombocytopenic purpura masquerading as ruptured ovarian cyst: successful nonsurgical management of this rare catastrophic event.

Chronic immune thrombocytopenic purpura has mild bleeding manifestations and severe bleeding requiring hospitalization is rare. We are reporting a case of a 19-year-old girl with chronic immune thrombocytopenic purpura who presented with spontaneous massive hemoperitoneum without any identifiable source of hemorrhage. We chose nonsurgical treatment over laparotomy, and the patient was managed successfully with parenteral steroids and platelet transfusion. In young women presenting with massive hemoperitoneum, undiagnosed immune thrombocytopenia should be considered as an etiology. In absence of any identifiable source of hemoperitoneum, these patients may not require laparotomy and treatment with intravenous corticosteroid and platelet transfusions may be preferrable and lifesaving.

A newborn with teratogenic effect of imatinib mesylate: a very rare case report.

OBJECTIVE: To report a case of teratogenic effect of imatinib mesylate (IM) in a newborn, whose mother was suffering from chronic myelogenous leukemia and was treated with IM for 4 years, including during her pregnancy. CASE PRESENTATION AND INTERVENTION: The newborn was diagnosed with microtia of the right ear, preauricular tag on the left side, absence of right depressor angular oris muscle, and imperforate anus. Infantogram showed dextrocardia, hemivertebrae in the thoracic region and cervical spina bifida occulta. The newborn was operated on for the imperforate anus and was discharged in good condition. CONCLUSION: This case revealed that IM is not safe for the fetus and leads to teratogenicity. Hence, we recommend that pregnant women should not be treated with IM.

Effect of dentin roughening and type of composite material on the restoration of non-carious cervical lesions: an in vivo study with 18 months of follow-up.

Objectives: The purpose of this study was to evaluate the impact of dentin roughening and the type of composite resin used (either bulk-fill flowable or nanohybrid) on the restoration of non-carious cervical lesions (NCCLs) with an 18-month follow-up period. Materials and Methods: This prospective split-mouth study included 36 patients, each with a minimum of 4 NCCLs. For each patient, 4 types of restorations were performed: unroughened dentin with nanohybrid composite, unroughened dentin with bulk-fill flowable composite, roughened dentin with nanohybrid composite, and roughened dentin with bulk-fill flowable composite. A universal bonding agent (Tetric N Bond Universal) was applied in self-etch mode for all groups. The restorations were subsequently evaluated at 6, 12, and 18 months in accordance with the criteria set by the FDI World Dental Federation. Inferential statistics were computed using the Friedman test, with the level of statistical significance established at 0.05. Results: The 4 groups exhibited no significant differences in relation to fracture and retention, marginal staining, marginal adaptation, postoperative hypersensitivity, or the recurrence of caries at any follow-up point. Conclusions: Within the limitations of the present study, over an 18-month follow-up period, no significant difference was present in the clinical performance of bulk-fill flowable and nanohybrid composite restorations of non-carious cervical lesions. This held true regardless of whether dentin roughening was performed.

Comparative assessment of the outcome of complete pulpotomy using mineral trioxide aggregate and Biodentine in mature permanent mandibular molars with symptomatic irreversible pulpitis: A randomized clinical trial with 18 months of follow-up.

Background: Mature permanent teeth with irreversible pulpitis have traditionally been managed with pulpectomy. With advancements in pulp biology and dental materials, many clinicians are using vital pulp therapies like pulpotomy to manage such teeth. The current study was conducted to help clinicians in making decisions about case selection and choice of material for such cases. Aim: This randomized clinical trial evaluated the outcome of complete pulpotomy, using mineral trioxide aggregate (MTA) and Biodentine, in permanent mandibular molars with symptomatic irreversible pulpitis (SIP). Materials and Methods: Fifty patients with moderate-to-severe pain in mandibular molars with SIP were included in this prospective, parallel, single-blind clinical trial. Coronal pulp was completely removed and hemostasis was achieved with a cotton pellet moistened with 2.5% sodium hypochlorite. Subsequently, the radicular orifices were randomly covered with MTA or Biodentine. All teeth were permanently restored with composite restoration at the same appointment. Clinical evaluation was performed at 1 week, 3 months, 6 months, 12 months, and 18 months and radiographic evaluation was done after 6 months, 12 months, and 18 months. Mann-Whitney U and Chi-square tests were utilized for statistical analysis. Results: Success rates of MTA and Biodentine pulpotomy were 63.6% and 69.6%, respectively, with no significant difference between the two groups at any follow-up period (P > 0.05). Conclusion: There were no significant differences in complete pulpotomy success rates between MTA and Biodentine over 18 months in mandibular molars with SIP.

In vitro evaluation of the effect of post system and length on the fracture resistance of endodontically treated human anterior teeth.

OBJECTIVES: The aim of this study was to evaluate the effect of post system and length on the fracture resistance of endodontically treated human anterior teeth. MATERIAL AND METHOD: Seventy-five extracted human incisors were endodontically treated, out of which 60 were decoronated 2 mm above the cementoenamel junction and divided into two experimental groups based on the type of post system to be used: glass fiber post (GFP) and Ribbond fiber post groups (RFP). Endodontically treated human anterior teeth in which no post was placed served as control group. Each group was divided into two subgroups according to the length of post space: 5 and 10 mm and all the samples were restored with metal crowns. The fracture resistance was measured by applying loads at an angle of 130° to the long axis of teeth in an Instron universal testing machine. RESULTS: The results revealed that GFP group at 10-mm post space length showed the significantly highest fracture resistance (740.2133 N) among all groups and subgroups. Decrease in post length resulted in the decrease in fracture resistance in GFP group (425.1867 N), whereas in group RFP 5-mm subgroup (299.6200 N) showed significantly higher fracture resistance than 10-mm subgroup (216.9300 N) but lesser than the control (437.8733 N) in both the subgroups. CONCLUSION: Glass fiber posts efficiently increase the fracture resistance of an endodontically treated tooth but the determination of optimal post length is also essential. CLINICAL RELEVANCE: The present investigation highlights the significance of using glass fiber posts in the restoration of endodontically treated teeth. Endodontically treated teeth restored with glass fiber posts showed increased fracture strength and favorable mode of fracture, and are therefore highly recommended to achieve better clinical outcomes.

Urinary retention unveiling deeply embedded multiple leiomyomas in women with Mayer-Rokitansky-Kuster-Hauser syndrome and its successful laparoscopic management: a case-report and literature review.

Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome is the second most common cause of primary amenorrhea with an incidence of 1:4000-5000 women. It is characterized by aplasia or hypoplasia of the uterus and the upper two-thirds of the vagina with normal ovaries and tubes and a normal secondary sexual characteristics. The occurrence of leiomyoma is common but it is rare to have leiomyoma in uterine remnant in MRKH syndrome. Although few cases of MRKH syndrome with leiomyoma have been reported in the literature, none presented with urinary retention. Here, we report a case of 28-year-old women who presented with urinary retention that unmasked deeply embedded huge fibroids in pelvis arising from a rudimentary uterine horns and its safe management via laparoscopic approach.

Evaluating Combined Effect of Oral Premedication with Ibuprofen and Dexamethasone on Success of Inferior Alveolar Nerve Block in Mandibular Molars with Symptomatic Irreversible Pulpitis: A Prospective, Double-blind, Randomized Clinical Trial.

INTRODUCTION: The success rate of inferior alveolar nerve block decreases exorbitantly in teeth with symptomatic irreversible pulpitis. The purpose of this prospective, double-blind, randomized clinical trial was to evaluate the combined effect of oral premedication with ibuprofen and dexamethasone on the success rate of inferior alveolar nerve block in mandibular molars with symptomatic irreversible pulpitis. METHODS: Ninety-four adult patients actively experiencing pain and diagnosed with symptomatic irreversible pulpitis willingly participated in this study. Preoperative pain was recorded on the Heft-Parker visual analog scale. Patients were randomly allocated to 4 different groups and received placebo, 0.5 mg dexamethasone, 800 mg ibuprofen, or a combination of 0.5 mg dexamethasone and 800 mg ibuprofen. One hour after oral premedication, all patients received standard inferior alveolar nerve block containing 2% lignocaine with 1:200,000 adrenaline. Access cavity preparation was initiated 15 minutes after the administration of anesthesia. Pain scores were recorded on VAS after anesthesia, at dentin penetration to pulp chamber opening, and on file placement. Success was defined as no or mild pain (0-54 mm) throughout the procedure. RESULTS: The chi-square test was used for qualitative data comparison. The 1-way analysis of variance test and post hoc Bonferroni test showed a statistically significant difference between the combination of 0.5 mg dexamethasone and 800 mg ibuprofen group and the other 3 groups (P < .001). CONCLUSIONS: Preoperative administration of a combination of dexamethasone and ibuprofen improved the success rate of inferior alveolar nerve block in mandibular molars with symptomatic irreversible pulpitis.

Sun Protection Behaviors in Head Start and Other Early Childhood Education Programs in Illinois.

Importance: Sun safety attitudes developed in early childhood can reduce lifetime UV radiation exposure and the risk of skin cancer. Objective: To assess the current policies, practices, and attitudes among caregivers regarding sun protection in children aged 2 to 6 years. Design, Setting, and Participants: A survey of 202 administrators or managers and teachers of Illinois Head Start/Early Head Start (HS/EHS) and day care centers was conducted from July 3 through 21, 2017. Organizations were randomly selected from 4 lists of urban, suburban, town, and rural locations and stratified to ensure population-based proportional representation of the Illinois population vulnerable to UV exposure. Program administrators or managers participated in a 5- to 10-minute telephone interview that assessed importance of health and sun protection behaviors, program practices, and demographic characteristics. Data analysis was conducted August 2, 2017. Main Outcomes and Measures: Outcomes included attitudes toward the importance of health behaviors in comparison with sun protective behaviors, reported use of sun protection (seeking shade, scheduling outdoor activities, sun protective clothing, and sunscreen practices), and sunburn prevalence. Results: Respondents (from 102 HS/EHS programs with 52% boys overall and a mean [SD] child age of 2.5 [0.5] y and 100 day care programs with 49% boys and age of 2.3 [0.4] y) stated that the 3 most important habits were good nutrition (66 [64.7%] HS/EHS, 71 [71.0%] day care), adequate exercise (41 [40.2%] HS/EHS, 55 [55.0%] day care), and brushing teeth (35 [34.3%] HS/EHS, 38 [38.0 %] day care). Scheduling outdoor activities to avoid peak sun intensity was performed less by HS/EHS programs (46 [45.1%]) in comparison with day care programs (71 [71.0%]; P < .001). Sunscreen was provided for students in 109 programs, but 84 (77.1%) did not allow children to apply sunscreen themselves. Half of the programs (100 of 202 [50.0%]) used spray sunscreen to avoid unnecessarily touching children. Most programs did not report any children having sunburns (129 [63.9%]) and followed heat index guidelines (114 [56.4%]). Conclusions and Relevance: Administrators and teachers did not identify sun safety as one of the most important health habits. While spray sunscreen was used frequently, avoiding spraying sunscreen directly on a child's face, which may get it into the child's eyes, was not done. The heat index was widely used to determine outdoor playtime. Adopting UV index policies could help prevent sunburns in early spring when the heat index is low but UV index is high. Dermatologists may assume responsibility for educating the administrators about the danger of spraying sunscreen into a child's face and the advantage of using the UV index to determine when sun protection is needed.

Effect of local anesthesia containing vasoconstrictor on sealing ability of dentin with two adhesive systems: Dye leakage and scanning electron microscopy study.

OBJECTIVES: To evaluate the effect of 2% lignocaine containing 1:80,000 adrenaline on the microleakage and ultrastructure of resin tooth interface using an acetone based total etch adhesive (Prime and Bond NT) and an ethanol water based self etch adhesive system (Xeno III). MATERIALS AND METHOD: Class V cavities were prepared on buccal surfaces of 72 maxillary first premolars scheduled for orthodontic extraction. In 36 premolars procedure was performed under local anaesthesia (LA) and in other 36 teeth without LA. Restorations were done with hybrid composite Spectrum TPH using either Prime and Bond NT or Xeno III bonding agents. RESULTS: Administration of 2% lignocaine with 1:80,000 adrenaline significantly reduced microleakage and improved quality of hybrid layer and tubular penetration in Prime and Bond NT specimens; but no significant effect was observed in Xeno III specimens. CONCLUSION: Under clinical conditions, administration of LA reduced microleakage and improved quality of hybrid layer and tubular penetration in total etch adhesive systems.

Melanoma simulation model: promoting opportunistic screening and patient counseling.

IMPORTANCE: Lack of training hampers melanoma recognition by physicians. OBJECTIVE: To evaluate a melanoma simulation model to teach visual assessment and counseling skills. DESIGN AND SETTING: Simulation model study in an academic research setting. PARTICIPANTS: A convenience sample of third-year medical students was randomly assigned to receive the intervention before or after a standardized patient. INTERVENTION: During the primary care clerkship, medical students participated in melanoma skills training using 2 simulation models replicating melanomas and abnormal or benign nevi. Scoring threshold rules for visual assessment and management of pigmented lesions and videos of patient counseling were provided. MAIN OUTCOME MEASURES: Identifying a melanoma moulage and counseling the standardized patient. Secondary measures were preintervention and 2-week postintervention knowledge, attitudes about and confidence in their ability to perform opportunistic surveillance and counseling, as well as identification on the model of clinically suspicious pigmented lesions, lesions needing a biopsy, and lesions to be monitored for change. RESULTS Among 74 students, confidence in their ability to perform opportunistic surveillance improved significantly after skills training (P < .05, χ2 test). Monitoring clinically suspicious lesions for change decreased from 16% (12 of 74) to 3% (2 of 74) and performing a biopsy increased from 80% (59 of 74) to 96% (71 of 74), monitoring benign lesions for change decreased from 43% (32 of 74) to 3% (2 of 74), and biopsying melanoma in situ increased from 10% (7 of 74) to 26% (20 of 74) (P < .05 for all, χ2 test). Detection of the melanoma moulage on the standardized patient occurred more often by trained students (P < .05, χ2 test). CONCLUSION AND RELEVANCE: A 1-hour melanoma simulation education and skills training experience improved performance of opportunistic surveillance, management, and patient counseling by third-year medical students. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01191294.

Management of early onset severe preeclampsia in a tertiary hospital in India: does expectant management alter perinatal outcome?

OBJECTIVE: The aims of the study were to find out the maternal and perinatal outcome of early onset severe preeclampsia (PE) in a tertiary care center in a developing country like India and to determine whether expectant management in such a setup improves the perinatal outcome. MATERIALS AND METHODS: It was a retrospective study. All women with early PE were admitted stabilized and evaluated. Expectant management was given whenever there was no indication for eminent delivery. The perinatal outcome of the expectant group was compared with that of the aggressive group, and appropriate statistical analysis was carried out. RESULTS: A total of 106 women were admitted with severe PE, 61 were treated aggressively, and 45 were stable enough to receive expectant management. The total days gained on expectant management was 7 days. Perinatal mortality was 31.13%. Perinatal outcome of the expectant and aggressive management groups did not differ (P = 0.141); there was no increase in maternal complications on expectant management. There were 2 cases of maternal mortality in the aggressively managed group. CONCLUSION: Perinatal mortality in severe PE is high. There was no increase in maternal morbidity on expectant management; however, there was no difference in perinatal mortality on expectant management.