In vitro effects of intravenous anesthetics on the sphincter of Oddi strips of sheep.

BACKGROUND: Intravenous anesthetics are often used for conscious sedation in endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic sphincter of Oddi (SO) manometry. This study was designed to investigate the direct effects of some intravenous anesthetics on SO in sheep. METHODS: In sheep SO rings, changes in isometric tension in response to cumulative concentrations of intravenous anesthetics were determined, and values for Emax (mean maximal inhibition) and pD2 (i.e. the negative logarithm of the concentration for the half-maximal response, EC50) were compared. RESULTS: Meperidine (10(-7) to 3 x 10(-5) M), fentanyl (10(-7) to 3 x 10(-5) M), midazolam (10(-7) to 3 x 10(-5) M) and propofol (10(-7) to 3 x 10(-4) M) induced concentration-dependent relaxations on SO precontracted with carbachol (10(-6) M). Emax and pD2 values following meperidine, fentanyl and midazolam administration were significantly greater than after propofol (p < 0.05). There were no significant differences in Emax and pD2 values for meperidine, fentanyl and midazolam. CONCLUSION: These results suggest that meperidine, fentanyl and midazolam are equipotent relaxants in the sheep SO in vitro. The relaxatory effect of propofol was 10 times less potent compared to the above agents, and it can be beneficial during SO manometry in controlled clinical human studies.     

Management of sigmoid colon volvulus

BACKGROUND/AIMS: Sigmoid colon is the most frequent site for a volvulus. The condition has been a formidable one, fraught with innumerable complications responsible for many deaths. In this report, we reviewed our experience with sigmoid colon volvulus. METHODOLOGY: We present our experience of 61 cases of sigmoid volvulus admitted to our department. Twenty-four patients were subjected to non-operative decompression and the others underwent emergency operation. RESULTS: Intestinal volvulus has quite a high morbidity and mortality. Mortality rate of elective resection following sigmoidoscopy was 7.6%. Mortality rate for emergency surgical detortion, primary resection and Hartman procedure were respectively 13%, 16.6% and 37.5%. Important factors such as the patient's features and frequent late diagnosis can influence the complicated outcome of the disease. Plain X-ray of the abdomen is helpful. CONCLUSIONS: Management with the conservative method of treatment in the form of detortion by sigmoidoscopy and rectal tube application is initially effective in most cases of volvulus of the sigmoid colon. On the other hand, elective or emergency sigmoid resection is the most effective treatment for the disease.     

A microchip approach for practical label-free CD4+ T-cell counting of HIV-infected subjects in resource-poor settings

Simple affordable CD4 cell counting is urgently needed to stage and monitor HIV-infected patients in resource-limited settings. To address the limitations of current approaches, we designed a simple, label-free, and cost-effective CD4 cell counting device using microfluidic technology. We previously described the fabrication of a microfluidic system for high-efficiency isolation of pure populations of CD4+ T cells based on cell affinity chromatography operated under controlled flow. Here, we compare the performance of a microfluidic CD4 cell counting device against standard flow cytometry in 49 HIV-positive subjects over a wide range of absolute CD4 cell counts. We observed a close correlation between CD4 cell counts from the microchip device and measurements by flow cytometry, using unprocessed whole blood from HIV-positive adult subjects. Sensitivities for distinguishing clinically relevant thresholds of 200, 350, and 500 cells/microL are 0.86, 0.90, and 0.97, respectively. Specificity is 0.94 or higher at all thresholds. This device can serve as a functional cartridge for fast, accurate, affordable, and simple CD4 cell counting in resource-limited settings.     

Cartilage graft or fascia in tympanoplasty in patients with low middle ear risk index (anatomical and audological results)

The aim of this study was to compare anatomic and audiological results of cartilage graft with temporal fascia graft in type 1 tympanoplasty patients with low middle ear risk index (MERI). In this retrospective study, 63 patients that underwent type 1 tympanoplasty with chondroperichondrial island graft between July 2009 and November 2010 were compared with 45 patients in whom temporal muscle fascia was used. Patients in both groups had low MERI values varying between 1 and 3. Five and nine patients underwent masteidectomy in cartilage and fascia group, respectively. Mean duration of follow-up was 11.9 ± 3.7 (5–17) months. Mean value was calculated at pre-operative and post-operative hearing threshold 0.5, 1, 2, 4 kHz, and air bone gap (ABG) gain was compared in both cartilage and fascia groups. when pre-operative and post-operative ABG gain were compared, significant decrease was seen in ABG levels (p < 0.001). However, no significant difference was seen in ABG gain values (p = 0.608), which was 10.1 ± 7.00 dB in cartilage group and 10.8 ± 5.38 dB in fascia group. In both groups, age, sex, and the addition of mastoidectomy procedure had no significant effect on ABG gain and success. Cartilage is a graft material that may be preferred without concern about the effects on hearing results, especially, in patients with low MERI values. The addition of mastoidectomy had no impact on the outcome of operation and audiological results. However, further studies with larger case series may be carried out to further clarify the issue.     

Effects of low molecular weight heparins and unfractionated heparin on viability of human umbilical vein endothelial cells

Aim

The aim of this study was to investigate the effects of bemiparin, nadroparin, enoxaparin, and heparin on viability of human umbilical vein endothelial cells (HUVEC).

Methods

Cultivation of HUVEC was performed in an incubator having 5 % CO₂ at 37 °C and with predefined supplemented medium, until cell monolayers attained confluence which occurred after 7 days. The assays were performed in the exponential growth phase of the cells. The cell viability was assessed using the cleavage of tetrazolium salts added to the culture medium. Heparin sodium, enoxaparin sodium, bemiparin sodium, and nadroparin calcium with concentrations of 100, 10, and 1 IU/100 μL were used for the proliferation assay in which cells were incubated for 24, 48, and 72 h with these drugs. The experiments were conducted in four replicates.

Results

Among the study drugs with maximal concentration used in the experiments (100 IU/100 μL), heparin was found to be associated with the lowest viability score in 24 and 48 h, while bemiparin showed the lowest at 72 h. Bemiparin 100 IU/100 μL was significantly associated with lower viability score than that of bemiparin 10 IU/100 μL and bemiparin 1 IU/100 μL at every time interval. Among gradual concentrations of enoxaparin, however, concentration of 1 IU/100 μL was associated with the lowest viability scores at every time point. Heparin 1 IU/100 μL, nadroparin 100 IU/100 μL, and enoxaparin 100 IU/100 μL groups had the highest viability score after 72 h of incubation.

Conclusion(s)

Among low molecular weight heparins (LMWHs), 100 IU/100 μL concentration of bemiparin was associated with a more pronounced effect on reducing viability of HUVEC after 72 h of incubation, while nadroparin 100 IU/100 μL and enoxaparin 100 IU/100 μL showed the least effects. LMWHs differ both from each other and heparin with respect to their effects on cellular viability of HUVEC in dose- and time-dependent manner.     

Effects of caustic lye injury to the esophageal smooth muscle reactivity: in vitro study

PURPOSE: We investigated late effects of caustic lye injury on esophageal smooth muscle reactivity in the rat model. MATERIALS AND METHODS: Male Sprague-Dawley rats were divided into two groups. Through a median laparatomy incision, abdominal esophageal segment was isolated. Orogastric and gastric (via gastrotomy) catheters were placed and tied over the isolated esophageal segment. Saline (0.9%) or 50% sodium hydroxide (1 ml) solution were instilled via orogastric catheter to the isolated segment in the control and caustic esophagus (CE group) groups, respectively. Then, the esophagus was rinsed with 0.9% saline via gastric catheter. The esophagus was removed and studied in organ chambers 28 days after the operation. RESULTS: Carbachol- and KCl-induced contractile responses of esophageal smooth muscle were significantly reduced in the CE group with decreased E(max) value compared with the control group. Relaxant responses to serotonin were significantly reduced in the CE group with decreased E(max) value compared with the control group. No significant differences were found in E(max) and pD(2) values for papaverine acting on esophageal strips from the two groups. CONCLUSION: The results provide evidence that, a surgically created caustic injury causes impaired smooth muscle reactivity that may contribute to esophageal motor dysfunction.     

The role of K(+) channels on the inhibitor effect of sevoflurane in pregnant rat myometrium.

Volatile anesthetics and K(+) channel openers inhibit spontaneous contractions in myometrial smooth muscle. Volatile anesthetics modulate K(+) channel activity. We investigated the role of two K(+) channel blockers on the effect of sevoflurane in pregnant rat myometrium. Term pregnant rat uteri were excised, and cross-sectional myometrial strips were mounted for isometric force recording. Sevoflurane inhibited the amplitude and frequency of spontaneous myometrial contractions in a concentration-dependent manner. The maximal inhibition measured in amplitude and frequency of spontaneous myometrial contractions with sevoflurane (at 3 minimum alveolar anesthetic concentration) was 44.32% and 33.32% of control contractions, respectively. Tetraethylammonium (TEA) and glibenclamide, K(+) channel blockers, increased spontaneous myometrial contractions in a concentration-dependent manner. Sevoflurane responses were repeated at concentrations with no effect on spontaneous contractility of TEA, a Ca(2+)-activated K(+) channel blocker, and glibenclamide, an adenosine triphosphate-sensitive K(+) channel blocker, in myometrial strips. TEA (3.10(-4) M) caused a significant reduction in sevoflurane-induced inhibitor responses, but glibenclamide (10(-6) M) did not. Sevoflurane-induced maximal inhibition (at 3 minimum alveolar anesthetic concentration) on amplitude and frequency of spontaneous myometrial contractions in the presence of TEA (3.10(-4) M) was 31.85% and 22.33% of control contractions, respectively (P < 0.05). These results suggest that the in vitroapplication of sevoflurane inhibited the amplitude and frequency of spontaneous myometrial contractions in pregnant rats in a concentration-dependent manner. Such inhibition was reduced by TEA. The inhibition of myometrial smooth muscle induced by sevoflurane seems to be mediated, at least in part, via activation of Ca(2+)-activated K(+) channels, because inhibition was reduced by TEA. IMPLICATIONS: In this study, we found that sevoflurane causes significantly decreased myometrial contractile activity in pregnant rats. The inhibition of myometrial smooth muscle induced by sevoflurane seems to be mediated, at least in part, via activation of Ca(2+)-activated K(+) channels, because inhibition was reduced by tetraethylammonium.     

Splenic abscesses due to Salmonella (report of two cases)

Two cases with splenic abscesses due to salmonella infection have been presented and the relevant literature has been reviewed. Diagnostic and therapeutic modalities have been discussed.