Morphology and performance relationship studies on biodegradable ternary blends of poly(3-hydroxybutyrate-co-3-hydroxyvalerate), polylactic acid,and polypropylene carbonate

A biodegradable ternary blend fabricated from polylactic acid (PLA), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and polypropylene carbonate (PPC) with a good balance of stiffness and toughness via optimizing the composition ratio and morphological structure is, to the best of the authors'' knowledge, reported here for the first time. The optimal blend formulation is comprised of 20% PLA, 40% PHBV, and 40% PPC, which possesses a tensile strength measuring 44 MPa and an elongation at break measuring at 215%. Thermal performance analysis revealed an HDT value of 72 °C. The Harkins equation predicts that the three immiscible polymers formed a complete wetting morphology, which was confirmed by scanning electrical microscopy. As the PPC content of the ternary blends is increased, the material undergoes morphological transition from droplet to co-continuous structure, resulting in significant improvement of elongation at break (approximately 40 times higher than that of the PLA–PHBV binary blend). Excellent stiffness and over 200% elongation at break make these sustainable ternary blends feasible for use in packaging as substitutes for certain non-biodegradable petroleum-based single use plastics.

Morphological arrangement leads to biodegradable stiffness–toughness–HDT balanced ternary blends.     

Exposure to Childhood Abuse and Later Substance Use: Indirect Effects of Emotion Dysregulation and Exposure to Trauma

Little is known about how emotion dysregulation (ED) and trauma exposure differentially affect the relationship between abuse in childhood and adult substance use. We examined associations between child abuse, trauma exposure, ED, and current substance use in an already existing dataset. Participants (N = 2,014 adults, 90% African American) had been recruited from an urban hospital for a parent study. Analyses showed that drug and alcohol use was significantly positively correlated with child abuse (emotional, physical, and sexual), later trauma exposure, and ED (all ps < .001). Linear regression showed that exposure to abuse when older than a child was significantly associated with drug and alcohol use independent of child abuse and demographic variables (R²Δ = .08, p < .001; R²Δ = .04, p < .001). ED was significantly associated with drug and alcohol use independently of child abuse, nonabuse trauma, and demographic variables (R²Δ = .02, p < .001; R²Δ = .04, p < .001). Multiple mediation analyses showed that ED and later trauma exposure accounted for variance in the association between emotional abuse and substance use (p < .001). A better understanding of vulnerabilities to additional traumatization and emotion‐regulation deficits in individuals who have been exposed to child abuse and in addition have comorbid substance use problems may inform treatments that lead to improved outcomes.     

Understanding the cognitive impact on children who are treated for medulloblastoma

OBJECTIVE: Risk-adapted treatment approaches employed within contemporary medulloblastoma treatment protocols aim to reduce the neurotoxicity directed at the central nervous system. Despite these important steps to reduce radiation dose exposure, an overwhelming majority of medulloblastoma survivors continue to experience academic failure and significant learning delays. METHODS: A review of the current literature is presented. RESULTS: Deficits in intellectual function, academic achievement, memory, attention, and processing speed are reported. Finally, intervention programs, including pharmacotherapy and experimental cognitive intervention studies, are discussed. A review of neuroimaging studies shows changes in brain tissue following chemotherapy and radiation treatment. CONCLUSIONS: Declining IQ and academic struggles may be predated by difficulties with attention, memory, and processing speed. More clinical trials directed at treating and preventing neurocognitive late effects through cognitive rehabilitation are needed.     

The perception of permanent, continuous, in service education for nurses in a school hospital

This study is aimed at discussing the conception of permanent, continuous, in service education among nurses at a school hospital. It is a research of qualitative nature, for which the data was gathered using the technique of focal group in six sessions recorded in audio and video. Nine nurses of a school hospital took part in it. For the analysis of the data was used the technique of collective subject speech, which consists of the organization and computation of the qualitative data of oral nature recorded, from which resulted a single speech. The research showed that the nurses differentiated the terms permanent education, continuous education and in service education, building their own concepts, highlighting the importance of differentiation in order to define the kind of approach to be taken to address the educative need presented.     

Laser utility in the treatment of hemorrhoidal pathology: a review of literature

Lasers in Medical Science - Hemorrhoidal disease is a common reason for consultation in proctology. It can be treated in several ways (medical, endoscopic, and surgical). Laser treatment has been...     

Intralenticular changes in eyes with mature senile cataract on modified posterior segment optical coherence tomography

Purpose:To study the morphological changes within mature senile cataracts on modified posterior segment optical coherence tomography (OCT).Methods:A cross-sectional observational study recruiting patients of mature cataracts admitted for elective cataract surgery in tertiary eye care. A modified OCT imaging of the lens was done and lenticular findings were noted by a single observer. Corresponding slit-lamp biomicroscopic findings and intraoperative experiences were also noted by a second observer and respective surgeons.Results:Forty-four eyes of 44 patients were included. The mean age of patients was 65 ± 5.7 years. The intralenticular findings were uniform in groups of eyes, and they were characterized into three stages. First was a stage of early lamellar separation where small intralenticular clefts were noted superficially. Second was the stage of established lamellar separation where crescentic fluid clefts appeared interspersed between the lens fibers, and the depth increased as a function of severity. Both these stages did not show any distinct slit-lamp or intraoperative findings. A third stage of liquefaction identified as extensive lamellar separation with subcapsular fluid pockets. This was also reflected in slit-lamp biomicroscopy, showing the hydrated cortex with intraoperative challenges. Two cases showed peculiar changes, one of a hyperreflective subcapsular sheath and another of superficial nuclear lamellar separation.Conclusion:Mature cataracts may also show graded progression, which could be delineated on lenticular OCT. This could be of immense help in pre-operative planning and optimal management of these high-risk cases.     

Medial approach to the peroneal vessels as recipients for free flap reconstruction of the leg

The anatomic variation in the branching pattern of the popliteal vessel has been well-established. Little has been written in the literature regarding recipient vessel selection for microvascular reconstruction in the lower extremity as it pertains to aberrant vascular anatomy. We present the case of a 57-year-old male patient who sustained a closed right lower extremity pilon fracture in a motor vehicle accident. The patient was initially treated with external fixation, which was followed by definitive open reduction and internal fixation 3 weeks later. Over the next 2 weeks, the patient developed skin ischemia of the anterior ankle. A free-tissue transfer was planned. A digital subtraction angiogram revealed absence of the posterior tibial (PT) vessels and an aberrant course of the peroneal (PR) artery. In the operating room, the medial distal leg was explored for the PT vessels, which were severely hypoplastic. Given the close proximity of the PR vessels, the dissection was extended proximally to assess these vessels for microvascular anastomosis. They were found to be suitable. A parascapular flap was harvested and transferred to the right leg wound without any significant stretch on the vessels for soft tissue coverage. The flap demonstrated excellent inflow and outflow, and the leg and foot remained well perfused. The patient's postoperative course was uncomplicated. The technique of exposing the peroneal vessels for microvascular anastomosis via a medial approach is described. This technique is an excellent option to have available when aberrant anatomy precludes the use more commonly utilized vessels.     

Safety and feasibility of concomitant surgery during holmium laser enucleation of the prostate (HoLEP)

Purpose

To determine the feasibility and outcomes associated with performing simultaneous surgical procedures during holmium laser enucleation of the prostate (HoLEP) in patients with benign prostatic hyperplasia and concomitant urologic conditions.

Methods

A retrospective review of patients that underwent a HoLEP was performed. Patients undergoing a concomitant procedure at the time of HoLEP were selected and stratified based on complexity of the secondary procedure (simple, intermediate, and complex) and matched based on age and prostate volume to patients undergoing only a HoLEP. Baseline characteristics, preoperative, operative, and postoperative outcomes were collected.

Results

A total of 372 HoLEPs were performed. Thirty-eight (10.2 %) patients underwent concomitant procedures at the time of HoLEP. Compared to the simple and intermediate secondary surgical procedures, the matched control group that underwent a HoLEP alone did not demonstrate statistically significant differences in the preoperative, operative, or postoperative outcomes. Patients with a complex secondary surgical procedure at the time of HoLEP had statistically significant differences in operative time (221 vs. 65 min, p = 0.007), estimated blood loss (92 vs. 33 mL, p = 0.012), catheter time (8.5 vs. 1 day, p = 0.041), and length of hospitalization (2 vs. 1 day, p = 0.032) compared to the control group.

Conclusions

Obstructive voiding symptoms secondary to BPH are common in older patients and may coincide with other concomitant lower urinary tract pathology that may require surgical intervention. Rather than staging surgical interventions, it appears that definitive treatment for BPH with HoLEP is safe and efficacious in those patients that also require secondary procedures.