Management of Preoperatively Suspected Choledocholithiasis: A Decision Analysis

Background  The management of symptomatic or incidentally discovered common bile duct (CBD) stones is still controversial. Of patients undergoing elective cholecystectomy for symptomatic cholelithiasis, 5–15% will also harbor CBD stones, and those with symptoms suggestive of choledocholithiasis will have an even higher incidence. Options for treatment include preoperative endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy (ERCP/ES) followed by laparoscopic cholecystectomy, laparoscopic cholecystectomy with intraoperative cholangiogram (LC/IOC), followed by either laparoscopic common bile duct exploration (LCBDE) or placement of a common bile duct double-lumen catheter with postoperative management. The purpose of this analysis was to determine the optimal management of such patients. Methods  A decision analysis was performed to analyze the management of patients with suspected common bile duct stones. The basic choice was between preoperative ERCP/ES followed by LC, LC/IOC followed by LCBDE, or common duct double-lumen catheter (Fitzgibbons tube) placement with either expectant management or postoperative ERCP/ES. Data on morbidity and mortality was obtained from the literature. Sensitivity analysis was done varying the incidence of positive CBD stones on IOC with associated morbidity and mortality. Results  One-stage management of symptomatic CBD stones with LC/LCBDE is associated with less morbidity and mortality (7% and 0.19%) than two-stage management utilizing preoperative ERCP/ES (13.5% and 0.5%). Sensitivity analysis shows that there is an increase in morbidity and mortality for LC/LCBDE as the incidence of positive IOC increases but are still less than two-stage management even with a 100% positive IOC (9.4%, 0.5%). If a double-lumen catheter is to be used for positive IOC, the morbidity would be higher than two-stage management only if the positive IOC incidence is more than 65% but still with no mortality. Conclusion  LCBDE has lower morbidity and mortality rates compared to preoperative ERCP/ES in the management of patients with suspected CBD stones even if the chance of CBD stones reaches 100%. Using a common duct double-lumen catheter may be considered if LCBDE is not feasible and the chance of CBD stone is less than 65%. Presented in part at the 49th Annual Meeting of the Society for Surgery of the Alimentary Tract [Poster Session], San Diego, CA, May 17–21, 2008     

Predicting fluid responsiveness: A review of literature and a guide for the clinician

Volume resuscitation is of utmost importance in the treatment of shock. It is imperative that this resuscitation be guided using a reliable method of ascertaining volume status to avoid the ill-effects of hypovolemia while also avoiding those of over-resuscitation. There are numerous tools and methods available in this era to aid the bedside physician in guiding volume resuscitation, many of which will be described in this review of literature.The methods to assess preload responsiveness are broadly divided into static and dynamic measurements. Static measurements involve ‘snapshot’ estimations of preload. Dynamic measurements rely on fluctuations in heart-lung interactions or a simulated volume challenge to predict whether increasing preload by volume loading will be beneficial. Dynamic measurements are favored over static measurements, however the conditions to be met for most dynamic measurements to be valid leave these methods to be used reliably in a very discrete critically-ill population. This issue is overcome by utilizing maneuvers that have been developed to assess fluid responsiveness that liberalize the conditions required for most dynamic measurements, such as passive leg raising, end expiratory occlusion, and mini-fluid boluses.This review of literature highlights the differences between static and dynamic measurements of fluid responsiveness, and proposes a guide to choosing the most reliable methods of ascertaining volume responsiveness individualized to each patient.     

Serum leptin and cholesterol levels in patients with bipolar disorder

Low cholesterol levels have been reported in patients with manic episodes. Leptin seems to be strongly associated with lipid metabolism. In the present study, therefore, serum total cholesterol and leptin levels were compared in 16 patients with manic episodes, 16 with bipolar I disorder in full remission and 16 healthy controls. The serum total cholesterol and leptin levels were measured and Young Mania Rating (YMRS) and Hamilton Depression Rating Scales (HAM-D) were administered for each subject. Both the patients with manic episodes and the patients with bipolar I disorder in full remission had markedly low serum cholesterol and leptin levels compared with controls, though the difference was more obvious in patients with manic episodes. In addition, there were negative correlations between YMRS scores and serum cholesterol or leptin levels in the patients with manic episodes. Our results suggest that the patients with manic episodes and those with bipolar I disorder in full remission seem to be associated with decreased serum cholesterol and leptin levels.     

A novel construct of an electrochemical acetylcholinesterase biosensor for the investigation of malathion sensitivity to three different insect species using a NiCr2O4/g-C3N4 composite integrated pencil graphite electrode

Herein, an electrochemical biosensor has been prepared to assess the sensitivity of an organophosphate insecticide, malathion, to acetylcholinesterase (AChE) enzyme of three insects including Apis mellifera (honeybee), Tribolium castaneum (red flour beetle), and Zootermopsis nevadensis (dampwood termite). A composite of nickel chromite (NiCr₂O₄) and graphitic carbon nitride (g-C₃N₄) was prepared and characterized for its morphological, chemical and electrical properties. The NiCr₂O₄/g-C₃N₄ composite integrated pencil graphite electrodes were used to covalently immobilize insect AChE enzymes and amperometric response of bioelectrodes was determined through cyclic voltammetry. The prepared bioelectrodes exhibited high enzyme immobilization efficiency and electro-catalytic performance. The integrated bioelectrodes could efficiently detect malathion induced inhibition of insects'' AChEs. The linear ranges for malathion were found to be 0.1–1.6 μM, 1–40 nM and 2–100 nM, and LODs were 2 nM, 0.86 nM and 2.3 nM for A. mellifera, T. castaneum, and Z. nevadensis, respectively. Additionally, the biosensing platform developed using A. mellifera AChE was found highly sensitive and effective for malathion recoveries from spiked wheat flour samples with high recovery rates. Moreover, the proposed method was adequately reproducible and selective. The results revealed that A. mellifera AChE is less sensitive to inhibition by malathion as compared to T. castaneum, and Z. nevadensis AChE. The experimental results were validated through computational docking of malathion with insect AChEs and the results were in correspondence to experimental outcomes. The proposed method can be a plausible alternate to conventional analytical methods to assess the pesticide sensitivity and toxicity of various compounds against insect enzymes.

An innovative electrochemical assay has been established to determine pesticide sensitivity against acetylcholinesterase and possible toxicity against insects. The analytical efficiency of three common insect AChEs was determined through this method.     

Expression of keratin K2e in cutaneous and oral lesions: association with keratinocyte activation,proliferation, and keratinization

The cytoskeleton in keratinocytes is a complex of highly homologous structural proteins derived from two families of type I and type II polypeptides. Keratin K2e is a type II polypeptide that is expressed in epidermis late in differentiation. Here we report the influence of keratinocyte activation, proliferation, and keratinization on K2e expression in samples of cutaneous and oral lesions. The normal expression of K2e in the upper spinous and granular layers of interfollicular epidermis is increased in keloid scars but showed distinct down-regulation in psoriasis and hypertrophic scars where keratinocytes are known to undergo activation. Unlike normal and psoriatic skin, K2e expression in hypertrophic and keloid scars began in the deepest suprabasal layer. In cutaneous basal and squamous cell carcinomas, K2e was absent in most tumor islands but the overlying epidermis showed strong expression. No significant K2e expression in nonkeratinized or keratinized oral epithelia, including buccal mucosa, lateral border of tongue and gingiva was detected. In oral lichen planus K2e expression was undetectable, but in benign keratoses of lingual mucosa induction of K2e along with K1 and K10 was observed. In mild-to-moderate oral dysplasia with orthokeratinization, K2e was highly expressed compared with parakeratinized areas but in severe dysplasia as well as in oral squamous cell carcinoma, K2e expression was undetectable. Taken together, the data suggest that K2e expression in skin is sensitive to keratinocyte activation but its up-regulation in oral lesions is a reflection of the degree of orthokeratinization.     

Is it important to classify ischaemic stroke?

Thirty-five percent of all ischemic events remain classified as cryptogenic. This study was conducted to ascertain the accuracy of diagnosis of ischaemic stroke based on information given in the medical notes. It was tested by applying the clinical information to the (TOAST) criteria. Hundred and five patients presented with acute stroke between Jan-Jun 2007. Data was collected on 90 patients. Male to female ratio was 39:51 with age range of 47-93 years. Sixty (67%) patients had total/partial anterior circulation stroke; 5 (5.6%) had a lacunar stroke and in 25 (28%) the mechanism of stroke could not be identified. Four (4.4%) patients with small vessel disease were anticoagulated; 5 (5.6%) with atrial fibrillation received antiplatelet therapy and 2 (2.2%) patients with atrial fibrillation underwent CEA. This study revealed deficiencies in the clinical assessment of patients and treatment was not tailored to the mechanism of stroke in some patients.     

Carbon tetrachloride induced kidney and lung tissue damages and antioxidant activities of the aqueous rhizome extract of <Emphasis Type="Italic">Podophyllum hexandrum</Emphasis>

Background  

The present study was conducted to evaluate the in vitro and in vivo antioxidant properties of aqueous extract of Podophyllum hexandrum. The antioxidant potential of the plant extract under in vitro situations was evaluated by using two separate methods, inhibition of superoxide radical and hydrogen peroxide radical. Carbon tetrachloride (CCl₄) is a well known toxicant and exposure to this chemical is known to induce oxidative stress and causes tissue damage by the formation of free radicals.