Multiscale Soft Surface Instabilities for Adhesion Enhancement

Soft polymeric gels are susceptible to buckling-induced instabilities due to their great compliance to surface deformations. The instability patterns at soft interfaces have great potential in engineering functional materials with unique surface properties. In this work, we systematically investigated how swelling-induced instability patterns effectively improved the adhesive properties of soft polydimethylsiloxane (PDMS) gels. We directly imaged the formations of the surface instability features during the relaxation process of a swollen gel substrate. The features were found to greatly increase the adhesion energy of soft gels across multiple length scales, and the adhesion enhancement was associated with the variations of contact lines both inside the contact region and along the contact periphery. We expect that these studies of instability patterns due to swelling will further benefit the design of functional interfaces in various engineering applications.     

Induced septic abortion: a major factor in maternal mortality and morbidity

BACKGROUND: Septic abortion is an infection of the uterus and its appendages following any abortion especially, illegally performed induced abortions. It is characterized by a rise of temperature to at least 100.4 degrees F, associated offensive or purulent vaginal discharge and lower abdominal pain and tenderness. AIM: To study maternal mortality and morbidity in induced septic abortions. METHODS: Induced septic abortions were analyzed between April 1992 and September 1999 in TU Teaching hospital. Morbidity indicators were surgery other than curettage, prolonged hospitalization and permanent damage. RESULTS: In 92 cases of induced septic abortions, comprising 6% of total abortions; nine deaths occurred because of disseminated intravascular coagulation, acute renal failure and adult respiratory distress syndrome. Vaginal, intraperitoneal and gum bleeding; epistaxis and malaena resulted in severe anemia (Hb < 6 gm/L) in 11 cases. Wound debridement and skin graft cured two cases of necrotizing fasciitis. One of four conservatively managed tubo-ovarian masses spontaneously drained rectally. In 15 cases laparotomy for pus drainage, salpingectomy, salpingo-oophorectomy, hysterotomy/uterine rent repair was conducted, along with four bowel surgeries and six hysterectomies were performed. Post-operative complications included burst abdomen (one case) and reopened pyoperitoneum, which resulted fecal fistula in three cases, one of these patients died. CONCLUSION: : Induced abortion was proven to be a major detrimental factor for maternal mortality. Morbidity was four times higher than mortality to the extent that patients suffered hemiplegia and forced barrenness.     

Long-term outcomes of augmentation ileocystoplasty in patients with spinal cord injury: a minimum of 10 years of follow-up

Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? Suprasacral spinal cord injuries can result in intractable detrusor overactivity adversely effecting patients’ quality of life. It can lead to high pressure bladder resulting in urinary incontinence and deterioration of upper tract function. Augmentation cystoplasty is an accepted procedure in treating refractory neurogenic detrusor overactivity. Several publications have reported on the short‐ to intermediate‐term outcomes with augmentation cystoplasty in patients with spinal cord injury. However, it is not known how these outcomes alter over a longer period. This study has a follow‐up of at least 10 years. It evaluates the durability of this procedure over the longer term. It also assesses the patients reported outcome over this period. This data can help counsel patients better when considering augmentation cystoplasty as a treatment option for the management of refractory neurogenic detrusor overactivity secondary to spinal cord injury.

OBJECTIVE

• ? To report the long‐term outcomes of augmentation ileocystoplasty (AIC) in patients with spinal cord injury (SCI), with a minimum follow‐up period of 10 years.

PATIENTS AND METHODS

• ? We retrospectively analysed all operations performed by a single surgeon at a specialist spinal unit.
• ? Outcomes were measured by comparing preoperative and follow‐up videocystometrograms (VCMGs).
• ? Complications were identified from case notes and the surgery database.
• ? Subjective assessment was through a previously validated questionnaire.

RESULTS

• ? The mean (range) follow‐up was 14.7 (10.5–20.3) years. There were 19 patients (12 males) with a mean (range) age at time of surgery of 28.9 (12–52) years. The mean (range) period from injury to surgery was 4.5 (0.3–22) years. All had suprasacral injuries.
• ? The VCMGs showed a significant improvement in bladder capacity and a decrease in intravesical pressures (P < 0.001).
• ? Long‐term complications included bladder stones (n= 4); urosepsis (n= 2); vesico‐ureteric reflux ([VUR]n= 2), VUR requiring ureteric re‐implantation (n= 1); neurogenic detrusor overactivity ([NDO]n= 1); and laparatomy for bowel obstruction (n= 1). Surveillance cystoscopies did not detect any bladder neoplasms.
• ? The response rate for the questionnaire survey was 14/17; 13/14 patients were satisfied with the operation such that they would consider it again or recommend it to a friend. No patient reported any significant changes in either bowel habit or sexual function.

CONCLUSIONS

• ? We found that AIC has excellent long‐term outcomes in the definitive management of refractory NDO in patients with SCI.
• ? The complications of AIC appear to be more than counterbalanced by a high level of patient satisfaction with the procedure and by the achievement of the primary aim of ensuring continence and upper tract safety in these patients.

     

Sprint prostheses used at the Paralympics: a proposal for an assessment method to maintain fairness

Background: Unique to sport with a disability such as those performed at the Paralympics, the need to improve the performance of lower limb prostheses can conflict with the need to provide an equal opportunity to win whilst still needing to encourage and maximise participation. Objectives: This paper extends previous research by attempting to propose a method suitable for sports governing bodies to help any functional assessment of sprinting lower limb prosthesis technology in the future. Study Design: The study comprises two elements: 1) A historical review and evaluation of drop jump assessment techniques. 2) A pilot test of a candidate using two mechanically different lower limb regions. Methods: A unilateral drop jump technique is assessed historically as an evaluation technique for sprinters with a lower-limb amputation. Further, a unilateral drop jump using mechanically altered lower limbs is piloted. Results: The historical review provides no evidence to suggest that this technique is not suitable for athlete participants. The pilot trials show a statistically stable and repeatable method of demonstrating a mechanical deficiency of one limb to another. Six jumps are suitable to obtain stable results but the mechanical behaviour of one limb may eventually change based on accumulated fatigue. Conclusions: The unilateral drop jump is shown to be viable for application to an athlete population with a lower limb unilateral amputation. Clinical relevance This paper develops previous sports stakeholder research and pilots an assessment strategy to provide a functional limb-to-limb comparison of the same lower limb region. This would potentially be used by both prosthetists and the sport's governing body to help maintain fairness in the sport as prosthesis technology develops.     

PTCH 1 staining of pancreatic neuroendocrine tumor (PNET) samples from patients with and without multiple endocrine neoplasia (MEN-1) syndrome reveals a potential therapeutic target

Pancreatic neuroendocrine tumors (PNETs) are rare, indolent tumors that may occur sporadically or develop in association with well-recognized hereditary syndromes, particularly multiple endocrine neoplasia type 1 (MEN-1). We previously demonstrated that the hedgehog (HH) signaling pathway was aberrantly up-regulated in a mouse model that phenocopies the human MEN-1 syndrome, Men1l/l;RipCre, and that inhibition of this pathway suppresses MEN-1 tumor cell proliferation. We hypothesized that the HH signaling pathway is similarly upregulated in human PNETs. We performed immunohistochemical (IHC) staining for PTCH1 in human fresh and archival PNET specimens to examine whether human sporadic and MEN-1-associated PNETs revealed similar abnormalities as in our mouse model and correlated the results with clinical and demographic factors of the study cohort. PTCH1 staining was positive in 12 of 22 PNET patients (55%). Four of 5 MEN-1 patients stained for PTCH1 (p = 0.32 as compared with sporadic disease patients). Nine of 16 patients with metastatic disease stained for PTCH1 as compared with zero of 3 with localized disease only (p = 0.21). No demographic or clinical features appeared to be predictive of PTCH 1 positivity and PTCH 1 positivity per se was not predictive of clinical outcome. PTCH1, a marker of HH pathway up regulation, is detectable in both primary and metastatic tumors in more than 50% of PNET patients. Although no clinical or demographic factors predict PTCH1 positivity and PTCH1 positivity does not predict clinical outcome, the frequency of expression alone indicates that perturbation of this pathway with agents such as Vismodegib, an inhibitor of Smoothened (SMO), should be examined in future clinical trials.     

Treatment of herniated lumbar disc by percutaneous laser disc decompression combined with synchronous suction technique through syringe

Objective: To compare the outcomes of percutaneous laser disc decompression (PLDD) and PLDD with synchronous suction through syringe in the patients with herniated lumbar disc (HLD). Methods: Forty-two patients with HLD on MRI and those who did not respond to conservative treatment for 6 weeks were randomly divided into group A and group B. In group A, the patients were treated with PLDD and those in group B with PLDD and synchronous suction through syringe. GaAIAS diode laser at 810 nm was used for the ablation in both groups. The treatment effect was evaluated by modified MacNab's criteria on the 7th, 30th and 90th day. Results: Evaluated by modified MacNab's criteria, the percentages of the excellent and good cases in total patients treated for group B and A were 80.95% and 57.14% on the 7th follow-up day, 85.71% and 66.67% on the 30th follow-up day, and 95.24% and 71.43% on the 90th follow-up day, respectively. Conclusion: Synchronous suction technique through syringe during PLDD improves the overall outcome in the treatment of herniated lumbar disc.