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A 59-year-old man with human immunodeficiency virus (HIV) was referred for persistently elevated liver enzyme activities. His HIV was well controlled on antiretroviral therapy and his viral load was undetectable. He had no history of chronic liver disease and had minimal alcohol intake. He was asymptomatic and his physical exam was unremarkable without any stigmata of liver disease. Beyond the elevations in alkaline phosphatase and gamma-glutamyl transferase, the rest of his laboratory work, including viral hepatitis serologies and serum α-fetoprotein, was within normal limits. A computed tomography (CT) scan revealed a mildly nodular liver but hepatic mass or ascites was not seen. He was subsequently followed every 3 to 6 months without any change in his clinical symptoms, laboratory values, or imaging tests. Two years after the original visit, the patient presented with acute onset of abdominal pain, an AFP of 15.8 ng/mL, and a 9-cm hepatic mass on imaging. Given his preserved liver function, he underwent right hepatic lobectomy. Histologic examination of the resected tissue was consistent with hepatocellular carcinoma (HCC). The uninvolved liver was noncirrhotic and unremarkable except for mild portal inflammation. As the vast majority of HIV patients who develop HCC have established chronic liver diseases such as hepatitis B and/or C along with cirrhosis, this case of HCC in an HIV patient without cirrhosis or viral hepatitis is rare. Although current screening guidelines recommend imaging only for patients with HIV and hepatitis B/C cirrhosis, closer monitoring may be important in HIV patients with even subtle liver dysfunction.  相似文献   
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We assessed ferumoxytol-enhanced brain MRI to identify monocyte/macrophage accumulation in HIV-associated neurocognitive disorder (HAND). Four HIV-infected subjects with undetectable HIV RNA levels on antiretroviral therapy, HIV DNA level in CD14+ cells ≥10 copies/106 cells, and cognitive impairment underwent ferumoxytol-enhanced brain MRI. On post-ferumoxytol susceptibility-weighted images, all HIV-infected subjects demonstrated a diffuse “tram track” appearance in the perivascular regions of cortical and deep white matter vessels suggesting ferumoxytol uptake in monocytes/macrophages. This finding was not present in an HIV-seronegative control. While ferumoxytol may have potential as an imaging biomarker for monocyte/macrophage accumulation in patients with HAND, future study is needed.  相似文献   
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Background

The rate of hernia formation after closure of 10–12 mm laparoscopic trocar sites is grossly under-reported. Using an animal model, we have developed a method to assess trocar site fascial dehiscence and the strength of different methods of fascial closure.

Materials and methods

Pigs (n = 9; 17 ± 2.5 lbs) underwent placement of 12 mm Hasson trocars with pneumoperitoneum maintained for 1 h. Three closure techniques (Figure-of-eight; simple interrupted; pulley) were compared with no fascial closure and to native fascia at five randomly allocated abdominal wall midline locations. Necropsy was performed on the fourth postoperative d. Statistical comparisons of tensile strength and breaking strength based on closure type and trocar location were made using ANOVA with Tukey’s tests.

Results

The mean (SD) force (Newtons) required for fascial disruption varied significantly with closure type [Native Fascia 170 (39), Figure-of-eight 169 (31), Pulley 167 (59), Simple Interrupted 151 (27), No Closure 108 (28)]; P = 0.007. The mean force required for fascial disruption was significantly increased for Native Fascia, Figure-of-eight, and Pulley relative to No Closure (P = 0.013, P = 0.015, P = 0.023, respectively). The mean (SD) force (in Newtons) required for fascial disruption also varied significantly with location of trocar [subxiphoid 181 (43), supraumbilical 151 (23), Umbilical 146 (23), infraumbilical 168 (62), suprapubic 120 (38)]; P = 0.03. The mean force for subxiphoid location was significantly increased relative to the suprapubic location (P = 0.021).

Conclusions

We have developed a novel assessment model that reliably detects differences in fascial integrity after laparoscopic trocar placement and closure. This model will allow for further testing of various trocars and closure techniques, and facilitate hernia prevention strategies.  相似文献   
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