Albumin adsorption on alkyl chain derivatized polyurethanes: I. The effect of C-18 alkylation

The initial adsorption rate of delipidized Human Serum Albumin (HSA) is increased by addition of C-18 alkyl chains to a polyurethane. The presence of alkyl chains does not appear to influence the total amount of HSA adsorbed after one hour exposure to a 5.0 mg/mL HSA solution. Neither does the desorption following one hour of adsorption appear to be influenced by the presence of alkyl chains. A study of the effects of solution concentration and temperature showed that the initial adsorption rates on both polymers are proportional to the protein concentration raised to the 0.36 power, and that alkylation of the polymer increases the activation energy of the initial adsorption rate above the 14 kJ/mol observed for the underivatized polyurethane. A new technique is presented to quantify the mass of adsorbed protein using Fourier transform infrared spectroscopy and attenuated total reflection optics. This technique uses the absorbance of bulk protein as an internal calibration reference, and appears to be as accurate and perhaps more precise than radiolabeling techniques.     

Median nerve compression in Proteus syndrome

Proteus syndrome is a multi–organ disorder, a prime feature of which is localized gigantism, usually clinically obvious. Symptoms secondary to hypertrophy of nerves has not been previously recognized as a part of the syndrome. Accepted: 16 May 1997     

Nucleoside analogs plus ritonavir in stable antiretroviral therapy-experienced HIV-infected children: a randomized controlled trial. Pediatric AIDS Clinical Trials Group 338 Study Team

CONTEXT: Although protease inhibitors are used routinely in adults with human immunodeficiency virus (HIV) infection, the role of these drugs in the treatment of clinically stable HIV-infected children is not clear. OBJECTIVE: To evaluate the safety, tolerance, and virologic response produced by a change in antiretroviral therapy in HIV-infected children who were clinically and immunologically stable while receiving previous therapy. DESIGN: The Pediatric AIDS Clinical Trials Group 338, a multicenter, phase 2, randomized, open-label controlled trial conducted from February 6 to April 30, 1997 (patient entry period); patients were followed up for 48 weeks. SETTING: Pediatric HIV research clinics in the United States and Puerto Rico. PATIENTS: Two hundred ninety-seven antiretroviral-experienced, protease inhibitor-naive, clinically stable HIV-infected children aged 2 to 17 years. INTERVENTIONS: Children were randomized to receive zidovudine, 160 mg/m2 3 times per day, plus lamivudine, 4 mg/kg 2 times per day (n = 100); the same regimen plus ritonavir, 350 mg/m2 2 times per day (n = 100); or ritonavir, 350 mg/m2 2 times per day, and stavudine, 4 mg/kg 2 times per day (n = 97). MAIN OUTCOME MEASURE: Plasma HIV-1 RNA levels at study weeks 12 and 48, compared among the 3 treatment groups. RESULTS: At study week 12, 12% of patients in the zidovudine-lamivudine group had undetectable plasma HIV RNA levels (<400 copies/mL) compared with 52% and 54% of patients in the 2- and 3-drug ritonavir-containing groups, respectively (P<.001). Through study week 48, 70% of children continued receiving their ritonavir-containing regimen. At study week 48, 42% of children receiving ritonavir plus 2 nucleosides compared with 27% of those receiving ritonavir and a single nucleoside had undetectable HIV RNA levels (P = .04); however, similar proportions in each group continuing initial therapy had HIV RNA levels of less than 10000 copies/mL (58% vs 48%, respectively; P = .19). CONCLUSIONS: In our study, change in antiretroviral therapy to a ritonavir-containing regimen was associated with superior virologic response at study week 12 compared with change to a dual nucleoside analog regimen. More children receiving ritonavir in combination with 2 compared with 1 nucleoside analog had undetectable HIV RNA levels at study week 48.     

Influence of morbid obesity on parathyroidectomy outcomes in primary hyperparathyroidism

Background

We sought to evaluate the influence of morbid obesity in patients undergoing parathyroidectomy for primary hyperparathyroidism (pHPT).

Methods

All patients with pHPT who underwent parathyroidectomy at a single institution between July 2002 and October 2008 were included. Body mass index (BMI), laboratorie vlaues, operative findings, and outcomes were examined.

Results

Two hundred thirteen of the 776 patients identified (28%) were morbidly obese (BMI ≥35 kg/m²). When compared with nonmorbidly obese patients, the morbidly obese patients were younger, had higher preoperative intact parathyroid hormone (iPTH) levels, heavier parathyroids, and required overnight stay more often (P <.05 for all). However, the rates of complications, eucalcemia, and recurrence were similar for all patients.

Conclusion

In this study, more than a quarter of the patients who underwent parathyroidectomy for pHPT were morbidly obese and had significantly higher preoperative iPTH levels, heavier parathyroids, and longer hospital stay but similar rates of complications and operative success.     

Flowcharts for the diagnosis and treatment of acute cholangitis and cholecystitis: Tokyo Guidelines

Diagnostic and therapeutic strategies for acute biliary inflammation/infection (acute cholangitis and acute cholecystitis), according to severity grade, have not yet been established in the world. Therefore we formulated flowcharts for the management of acute biliary inflammation/infection in accordance with severity grade. For mild (grade I) acute cholangitis, medical treatment may be sufficient/appropriate. For moderate (grade II) acute cholangitis, early biliary drainage should be performed. For severe (grade III) acute cholangitis, appropriate organ support such as ventilatory/circulatory management is required. After hemodynamic stabilization is achieved, urgent endoscopic or percutaneous transhepatic biliary drainage should be performed. For patients with acute cholangitis of any grade of severity, treatment for the underlying etiology, including endoscopic, percutaneous, or surgical treatment should be performed after the patient's general condition has improved. For patients with mild (grade I) cholecystitis, early laparoscopic cholecystectomy is the preferred treatment. For patients with moderate (grade II) acute cholecystitis, early laparoscopic or open cholecystectomy is preferred. In patients with extensive local inflammation, elective cholecystectomy is recommended after initial management with percutaneous gallbladder drainage and/or cholecystostomy. For the patient with severe (grade III) acute cholecystitis, multiorgan support is a critical part of management. Biliary peritonitis due to perforation of the gallbladder is an indication for urgent cholecystectomy and/or drainage. Delayed elective cholecystectomy may be performed after initial treatment with gallbladder drainage and improvement of the patient's general medical condition.     

Diagnostic laparoscopy for chronic abdominal pain after gastric bypass.

BACKGROUND: To evaluate, in an observational study, the utility of diagnostic laparoscopy as a tool to evaluate patients with abdominal pain of unknown etiology after gastric bypass surgery. METHODS: A retrospective analysis was performed of data from patients who had undergone laparoscopy for diagnosis or treatment of abdominal pain. This study included 13 patients with negative preoperative radiographic and/or endoscopic findings. RESULTS: A total of 13 patients who had undergone Roux-en-Y gastric bypass underwent diagnostic laparoscopy for abdominal pain. The findings included internal hernia (4), adhesions (3), ventral hernia (2), partial small bowel obstruction (1), and chronic cholecystitis (1). There were 2 negative laparoscopies, while a diagnosis was made in 85%. After an average follow-up of 3.2 months, 7 of 11 patients had unresolved abdominal pain and 4 patients experienced pain resolution (2 patients were lost to follow-up). CONCLUSION: The results from this small retrospective study suggest that significant pathologic findings can be identified in most patients who have negative preoperative evaluation findings; however, the efficacy of diagnostic laparoscopy to eliminate pain in this patient population requires additional study. Despite the potential complications, we believe that diagnostic laparoscopy has a role in the diagnosis and treatment of chronic abdominal pain after gastric bypass.     

Primary sclerosing cholangitis: role of extrahepatic biliary resection

BACKGROUND: Most centers advocate orthotopic liver transplantation (OLT) for patients with primary sclerosing cholangitis (PSC) and cirrhosis. Management of PSC patients without cirrhosis remains controversial. We examined the results of extrahepatic biliary resection (EHBR) for PSC. STUDY DESIGN: Between 1981 and 2006, 126 patients with PSC underwent EHBR (n = 77) or OLT (n = 49). Data on biliary drainage procedures, perioperative morbidity, and longterm survival were collected and analyzed. RESULTS: Of 77 patients undergoing EHBR, mean preoperative bilirubin level was 5.6 mg/dL. Nine (11.7%) patients had cirrhosis. Most patients had preoperative biliary drainage (ERCP, 61.0%; PTC, 67.5%). At operation, 73 (94.8%) patients underwent EHBR, including hepatic duct bifurcation. Most patients also had insertion of bilateral transhepatic silicone elastomer biliary stents; 4 (5.2%) underwent EHBR with stent insertion plus hepatectomy. For EHBR patients, perioperative complication rate was 38.7% and 30-day mortality was 3.9%. Bilirubin levels significantly decreased postoperatively (mean drop 3.8 mg/dL; p < 0.01). At 3 years, 57.1% of patients had no PSC-related readmissions, and 16.2% had more than 3. At a median followup of 10.5 years, 5- and 10-year survival was 76.4% and 52.7%, respectively. Cholangiocarcinoma did not develop in any patients, and only seven required OLT. Factors associated with worse survival included postoperative bilirubin >or= 2 mg/dL and history of cirrhosis (both p < 0.001). In patients undergoing EHBR, noncirrhotic patients had significantly better longterm outcomes versus cirrhotic patients (10-year survival, 60.2% versus 12.0%; p < 0.001). In contrast, 10-year survival of OLT patients with cirrhosis was 57.0%. CONCLUSIONS: Noncirrhotic patients with PSC can be successfully managed with EHBR. EHBR for noncirrhotic patients is associated with low perioperative morbidity, few readmissions, no new cholangiocarcinomas, and 10-year survival > 60%. OLT should be reserved for patients with PSC and associated hepatic cirrhosis.