Peripheral low-density area of hepatic tumors: CT-pathologic correlation

To aid in the distinction between colorectal cancer metastasis to the liver and hepatocellular carcinoma, findings on computed tomographic (CT) scans taken more than 5 minutes after contrast material administration ("late-enhanced CT scans") and pathologic findings were compared. Late-enhanced CT scans of metastatic adenocarcinoma showed a peripheral low-density area (PLDA) that corresponded to viable tumor and a central high-density area that represented fibrous connective tissue. This phenomenon was recognized in 15 of 20 (75%) patients with metastatic adenocarcinoma and in one of 50 (2%) patients with hepatocellular carcinoma. Late-enhanced CT scans may be useful in distinguishing between metastatic nonmucinous colorectal cancer and hepatocellular carcinoma.     

Intensive care units, scarce resources, and conflicting principles of justice

The authors approach the societal problem of the just distribution of health care resources by exploring one example-- the allocation of intensive care unit (ICU) beds between present patients and those awaiting admission--within the context of not expending a disproportionate share of resources for marginal benefit. They propose the metaphor of the societal "insurance policy" under which decisions regarding the investment of resources to meet various possible contingencies are made in advance. They then analyze several cases to demonstrate how various economic and moral options of the "insurance policy" could be applied in ICUs.     

Association between Preoperative Long-Chain Polyunsaturated Fatty Acids and Oxidative Stress Immediately after Total Knee Arthroplasty: A Pilot Study

Quadriceps muscle atrophy following total knee arthroplasty (TKA) can be caused by tourniquet-induced ischemia–reperfusion (IR) injury, which is often accompanied by oxidative stress and inflammatory responses. n-3 long-chain polyunsaturated fatty acids (LCPUFAs), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), exert antioxidant and anti-inflammatory effects against IR injury, whereas n-6 LCPUFAs, particularly arachidonic acid (AA), exhibit pro-inflammatory effects and promote IR injury. This study aimed to examine whether preoperative serum EPA + DHA levels and the (EPA + DHA)/AA ratio are associated with oxidative stress immediately after TKA. Fourteen eligible patients with knee osteoarthritis scheduled for unilateral TKA participated in this study. The levels of serum EPA, DHA, and AA were measured immediately before surgery. Derivatives of reactive oxygen metabolites (d-ROMs) were used as biomarkers for oxidative stress. The preoperative serum EPA + DHA levels and the (EPA + DHA)/AA ratio were found to be significantly negatively correlated with the serum d-ROM levels at 96 h after surgery, and the rate of increase in serum d-ROM levels between baseline and 96 h postoperatively. This study suggested the preoperative serum EPA + DHA levels and the (EPA + DHA)/AA ratio can be negatively associated with oxidative stress immediately after TKA.     

Identification of α1-adrenoceptor subtypes in the dog prostate

Summary The ₁-adrenoceptor subtypes of dog prostate were characterized in binding and functional experiments. In saturation experiments, [³H]prazosin bound to ₁-adrenoceptors with high affinity. In the displacement experiments, unlabelled prazosin and WB4101 biphasically inhibited the binding of 400 pM [³H]prazosin, suggesting the presence of at least two distinct affinity sites for prazosin or WB4101. The proportion of high-affinity sites was approximately 10%. HV723 also recognized two distinct affinity sites but the proportion of high-affinity sites was approximately 20%. From these results the presence of three distinct ₁-adrenoceptor subtypes was suggested: presumably subtypes _1A (high affinity for prazosin and WB4101), _1N (high affinity for only HV723) and _1L (low affinity for the three antagonists) according to the recently proposed ₁-adrenoceptor subclassification. The density of subtype _1L was much higher than that of subtypes _1A and _1N subtypes. In the functional experiments, prazosin, WB4101 and HV723 competitively antagonized the contractile response to noradrenaline with low affinities close to those estimated for the _1L subtypes. These results suggest that the contractile response to noradrenaline in the dog prostate is mediated predominantly through _1L subtype -adrenoceptors.     

Rathke cleft cyst: MR and biomedical analysis of cyst content

PURPOSE: At least one type of Rathke cleft cyst has unique MR findings, specifically, high intensity on T1-weighted images and iso- to low intensity on T2-weighted images relative to white matter. To clarify the influence of cyst content on MR images, we analyzed the cyst content by biomedical methods after surgical removal. METHOD: We studied five patients diagnosed with Rathke cleft cyst, whose MR images showed high intensity on T1-weighted images and iso- to low intensity on T2-weighted images. After surgery, total protein and cholesterol levels were quantified, and correlations of protein and cholesterol content with T1 and T2 signal intensities were performed in vitro. RESULTS: All five cysts had very high concentrations of protein (11,700-26,600 mg/dl, mean 17,940 mg/dl) with nearly no cholesterol (at most 2.0 mg/dl). Along with increases in protein concentration in vitro, the signal intensity of T1-weighted images increased, while that of T2-weighted images decreased. In contrast, the cholesterol concentration sequence influenced the signal intensity of neither T1- nor T2-weighted images. CONCLUSION: The unique MR finding of Rathke cleft cysts--high signal intensity on T1-weighted images and low signal intensity on T2-weighted images--might depend mainly on protein concentration, not on cholesterol.     

Double muscle transfer for upper extremity reconstruction following complete avulsion of the brachial plexus

Recent interest in reconstruction of the upper limb following brachial plexus injuries has focused on the restoration of prehension following complete avulsion of the brachial plexus. The authors use free muscle transfers for reconstruction of the upper limb to resolve the difficult problems in complete avulsion of the brachial plexus. This article describes the authors' updated technique--the double free muscle procedure. Reconstruction of prehension to achieve independent voluntary finger and elbow flexion and extension by the use of double free muscle and multiple nerve transfers following complete avulsion of the brachial plexus (nerve roots C5 to T1) is presented. The procedure involves transferring the first free muscle, neurotized by the spinal accessory nerve for elbow flexion and finger extension, a second free muscle transfer reinnervated by the fifth and sixth intercostal nerves for finger flexion, and neurotization of the triceps brachii via its motor nerve by the third and fourth intercostal motor nerves to extend and stabilize the elbow. Restoration of hand sensibility is obtained via the suturing of sensory rami from the intercostal nerves to the median nerve. Secondary reconstruction, including arthrodesis of the carpometacarpal joint of the thumb and glenohumeral joint, and tenolysis of the transferred muscle and distal tendons, improve the functional outcome. Based on the long-term result, selection of the patient, donor muscle, and donor motor nerve were indicated. Most patients were able to achieve prehensile functions such as holding a can and lifting a heavy box. This double free muscle transfer has provided prehension for patients with complete avulsion of the brachial plexus and has given them new hope to be able to use their otherwise useless limbs.     

Serosurvey of wild rodents for Rickettsioses (spotted fever, murine typhus and Q fever) in Java Island, Indonesia

The prevalence of antibodies against spotted fever group rickettsia (SFGR), murine typhus and Q fever were investigated in wild rats captured in Indonesia. Sera of 327 rats were collected from Jakarta and Boyolali on Java Island. The prevalences of antibodies against SFGR and murine typhus were 128 (39.1%) and 48 (14.7%), respectively. Antibodies against Q fever were not detected in these serum samples. Antibodies against SFGR were found in all species of rats (20.8–51.9%). The antibody positive rate against murine typhus in Rattus norvegicus (38.0%) was significantly higher than that in other rat species (0–4.8%, p < 0.01). The antibody positive rates against SFGR and murine typhus in rats captured in Jakarta were significantly higher than those in rats captured in Boyolali (p < 0.01). In this survey, all species of rats had antibodies against SFGR, indicating that the 4 species of tested rats (R. norvegicus, R. rattus, R. exulans, R. tiomanicus) were infected with SFGR and that SFGR may infest the whole of Java Island. Most of the rats that were antibody-positive against murine typhus were captured in Jakarta. Therefore, R. norvegicus and R. rattus are likely to be important hosts of murine typhus in Jakarta. The antibody-positive rates against SFGR and murine typhus in rats captured in the dry season were significantly higher than those in rats captured in the rainy season. This may coincide with the active periods of ticks and fleas in Indonesia.