Aortic Transection after Blunt Abdominal Trauma in a Child.

Abdominal aortic injury secondary to blunt abdominal aortic trauma (BAAI) is rare in children but frequently occurs in association with other injuries, including bowel injury and vertebral fracture. We present a case of a 14-year-old boy who sustained a partial transection of the infrarenal aorta with a lumbar chance fracture and small bowel injury after a motor vehicle accident. Repair was performed with bowel resection followed by Dacron graft interposition. We reviewed the literature on BAAI in children with a focus on the method of repair of these injuries.

Arteriovenous Access superficialization: A New Technique and Review of Options.

BACKGROUND: Up to 30% of autogenous cephalic vein arteriovenous fistulas (AVFs) are too deep for reliable cannulation. Techniques to superficialize these AVFs have been described previously. This study describes a new surgical technique for AVF superficialization and provides a review of the alternative techniques. METHODS: The path of the fistula is marked using ultrasound, and transverse incisions are made along this path. The underlying tissue is separated from the dermis over this area to expose the fistula outflow vein. The mobilized vein is then elevated and "trapped" directly under the dermis by closing the superficial fascia and adipose tissue beneath it. RESULTS: Between March 2016 and February 2019, 23 patients underwent superficialization using this technique at two centers. The mean time between AVF creation and superficialization was 6.3 months, and the time to first use for hemodialysis after superficialization was 38.8 ± 27.9 days. The average presuperficialization depth was 7.1 ± 2.4 mm and average postsuperficialization depth was 3.7 ± 2.7 mm (P = 0.002). Sixteen fistulas were successfully accessed for a cannulation rate of 89%. 94.7% of fistulas remained patent at last visit, with only one thrombosed 8-10 weeks after superficialization. CONCLUSIONS: This technique appears to be both safe and effective, and results in a vein that is immediately subdermal without major contour deformity. Early outcomes are comparable to those alternative methods described in the literature.

TSLP production by epithelial cells exposed to immunodeficiency virus triggers DC-mediated mucosal infection of CD4+ T cells.

Mucosal dendritic cells have been implicated in the capture, storage, and transmission of HIV to CD4(+) T cells as well as in the promotion of HIV replication in activated CD4(+) T cells during the cognate T-cell and DC interaction. We report that HIV induces human genital mucosal epithelial cells to produce thymic stromal lymphopoietin (TSLP) via activation of the NFkappaB signaling pathway. The TSLP secreted by HIV exposed epithelial cells activated DC, which promoted proliferation and HIV-1 replication of co-cultured autologous CD4(+) T cells. In rhesus macaques, we observed dramatic increases in TSLP expression concurrent with an increase in viral replication in the vaginal tissues within the first 2 weeks after vaginal SIV exposure. These data suggest that HIV-mediated TSLP production by mucosal epithelial cells is a critical trigger for DC-mediated amplification of HIV-infection in activated CD4(+) T cells. The cross talk between mucosal epithelial cells and DC, mediated by HIV-induced TSLP, may be an important mechanism for the high rate of HIV infection in women through the vaginal mucosa.

Technical note: An alternative method for AV access superficialization.

INTRODUCTION: An arteriovenous fistulae for dialysis access is only functional if superficial enough for reliable cannulation. We describe a previously unreported technique to superficialize arteriovenous fistulae too deep for reliable cannulation. METHOD: The path of the fistula is marked using ultrasound, and three to four transverse incisions are made along this path. The subcutaneous tissue is separated from the dermis over this entire area. The fistula is then accessed through transverse incisions and by dividing the overlying adipose tissue. The mobilized vein is then "trapped" directly under the dermis by closing the superficial fascia and adipose tissue beneath it and using this tissue to elevate the fistula. No anastomotic revisions are necessary, and moderate straightening can be performed. RESULTS: We have performed this procedure on 20 patients with 100% technical success. One fistula had thrombosis within 8-10 weeks of the superficialization procedure and one patient refused access due to pain, but all other fistulas were successfully cannulated. Two patients were lost to follow-up, and one patient developed skin breakdown in the area of the flap which delayed cannulation. Our 3-month patency was 94.4% with a functional patency, defined as a clinically patent fistula successfully being used for hemodialysis, of 87.5%. CONCLUSION: The technique described allows elevation of the vein to the level of the dermis without division and re-anastomosis or re-tunneling, through several small incisions maintaining virgin skin and normal contour for easier cannulation.

Dynein light chain 1 peptide inhibits human immunodeficiency virus infection in eukaryotic cells.

Human immunodeficiency virus (HIV) uses kinases such as Pak1 and macropinocytosis for a productive infection. Recently dynein light chain 1 (DLC1), a component of the dynein motor, was identified as a Pak1 substrate and interacted with the C-terminal region of DLC1 (aa 61-89). The dynein motor is implicated in retrograde transport, also of HIV, to the nucleus. It is known that DLC1 is important in macropinocytosis, and anti-dynein antibodies inhibit a productive HIV infection. Here, we show that in Hela-beta-gal cells macropinocytosis was effectively blocked by a peptide spanning the C-terminal 19 amino acids of DLC1. We also found that the DLC1 peptide was capable of inhibiting the early entry steps of HIV, and the DLC1 peptide efficiently inhibited a productive HIV infection, and cooperated with the anti-HIV activity of CD4 antibodies. Taken together, the potentially therapeutic DLC1 peptide represents an interesting class of HIV inhibitors, targeting an essential cellular component for HIV infection. Our findings raise the possibility that the use of a DLC1 peptide in combination with currently used anti-HIV agents, might offer additional arsenal against HIV infection in human cells.

Nerium oleander derived cardiac glycoside oleandrin is a novel inhibitor of HIV infectivity.

We evaluated the effectiveness of Anvirzel™, an aqueous extract of Nerium oleander on HIV infection of human peripheral blood mononuclear cells. Oleandrin, the principle cardiac glycoside (CG) in Anvirzel™ has been shown to exhibit anti-cancer properties but its efficacy against HIV is unknown. Treatment with Anvirzel™ significantly reduced the infectivity of virus produced from infected cells without any change in the total amount of virus produced. This is in contrast to treatment with AZT, a potent inhibitor of HIV replication that has been shown to significantly reduce virus production. Relative to untreated cultures, virus in cultures treated with oleandrin had significantly reduced expression of the envelope protein gp120, the sole determinant of virus infectivity, suggesting a novel mechanism underlying the impaired infectivity. These results support the potential utility of the Nerium oleander aqueous extract, containing the CG oleandrin as a novel candidate anti-HIV therapeutic.

Critical role of Arg59 in the high-affinity gp120-binding region of CD4 for human immunodeficiency virus type 1 infection.

Human immunodeficiency virus type 1 (HIV-1) infection is initiated by the binding of the viral envelope protein gp120 to the host cell CD4 receptor through a high-affinity interaction involving amino acids 39-60 within the CD4. We obtained evidence demonstrating functional importance of this region in CD4 for viral infectivity by showing that a synthetic peptide corresponding to this CD4 sequence exhibited competitive binding to gp120 and significantly reduced infection by diverse HIV-1 strains, including primary isolates. Treatment of HIV-1-infected cells with this CD4 peptide induced shedding of gp120 and exposure of the transmembrane protein gp41. Furthermore, we observed that deletion or substitution of arginine at position 59 (Arg(59)) within the CD4 peptide sequence abrogated its gp120-shedding property. These results indicate a critical role for Arg(59) in the CD4 for conformational changes in gp120 during the sequential process of entry and infection by HIV-1.