BI Group Research Articles

Rapid synthesis, structure and photocatalysis of pure bismuth A-site perovskite of Bi(Mg3/8Fe2/8Ti3/8)O3.

Bi(Mg3/8Fe2/8Ti3/8)O3, a member of a small group of pure Bi(3+) A site perovskites, exhibiting a high ferroelectric Curie point (Tc), was rapidly synthesized by a sample method of molten salt synthesis. The purity of Bi(Mg3/8Fe2/8Ti3/8)O3 samples is directly affected by the reaction conditions such as the soaking temperature, and the heating and cooling rates. The as-prepared Bi(Mg3/8Fe2/8Ti3/8)O3 particles are well-formed, cube-shaped single-crystals with sizes ranging from 200-300 nm. The chemical states of Bi and Fe ions are Bi(3+) and Fe(3+) in Bi(Mg3/8Fe2/8Ti3/8)O3. UV-vis diffuse reflectance spectra and preliminary photocatalytic experiments indicate that the pure Bi(3+) A site perovskite of Bi(Mg3/8Fe2/8Ti3/8)O3 has a suitable energy bandgap (1.86 eV) and shows obvious photocatalytic activity for the decolorization of methyl blue under visible-light irradiation. The present work suggests potential future applications of Bi(Mg3/8Fe2/8Ti3/8)O3 in photocatalysis and ferroelectric photovoltaic effects.

A new study on the energy transfer in the color-tunable phosphor CaWO4:Bi

In this article, the scheelite-structured phosphors of CaWO4 and Bi(3+) doped CaWO4 were successfully synthesized by the high temperature solid state reaction, and the photoluminescence (PL) properties and decay curves of the samples were investigated between 10 and 300 K. The results have shown clearly that the sample emission is tunable via tailoring the energy transfer between the Bi(3+) and WO4(2-) anion groups by the selection of either proper bismuth content or excitation scheme. Depending on the excitation scheme, energy transfer does happen from Bi(3+) to WO4(2-) or in the reverse, which, however, has never been noticed. Direct spectroscopic evidences as well as the mechanism have been presented for these processes in this work.

Abstract 18119: Mir-16 Modulates Endothelial Dysfunction After Balloon Injury in a Rat Model of Chronic Peripheral Ischemia

Background: Peripheral ischemia is associated with endothelial dysfunction in the coronary district and represents an important predictor of future cardiovascular events such as myocardial infarction and stroke. MicroRNAs (miRs) play an important regulatory role in cells of the vascular wall. Thus, the aim of the present study was to evaluate the role of miRs in mediating remote endothelial dysfunction in a model of peripheral ischemia. Methods and Results: Wistar male rats, were divided into the following groups: no treatment (sham); vascular injury on the carotid artery by balloon catheter (BI); femoral artery ligation (AL); ligation of the femoral artery followed, after 21 days, by balloon injury (AL+BI). At 21-days-evaluation, real time RT-PCR showed a profound up-regulation of miR-16 levels within ECs extracted by injured carotid artery of AL+BI group compared to the BI group. A bioinformatics approach revealed highly conserved binding sites for miR-16 in the 3’UTR of ARHGDIA (Rho-GDP dissociation inhibitor 1), an inhibitor of Rho signaling. Interestingly up-regulation of miR-16 was associated with a reduction of the ARHGDIA-transcript levels and a higher activation of the RhoA pathway, with consequent reduction of nitric oxide bioavailability. Accordingly, inhibition of miR-16 in ECs resulted in increased mRNA and protein levels of eNOS, with increased NO production, while up-regulation of miR-16 resulted in increased NF-kB activation in ECs. Conclusions: The expression levels of miR-16 are increased in the vascular endothelium of injured arteries in rats with a model of chronic peripheral ischemia, over rats without peripheral ischemia. Such modulation of miR-16 levels may play a key role in modulating endothelial dysfunction through modulation of the RhoA signaling pathway and the transcription factor NF-kB.

Nontoxigenic Clostridium difficile Protects Hamsters against Challenge with Historic and Epidemic Strains of Toxigenic BI/NAP1/027 C. difficile

Nontoxigenic Clostridium difficile (NTCD) has been shown to prevent fatal C. difficile infection in the hamster model when hamsters are challenged with standard toxigenic C. difficile strains. The purpose of this study was to determine if NTCD can prevent C. difficile infection in the hamster model when hamsters are challenged with restriction endonuclease analysis group BI C. difficile strains. Groups of 10 hamsters were given oral clindamycin, followed on day 2 by 10(6) CFU of spores of NTCD strain M3 or T7, and were challenged on day 5 with 100 CFU of spores of BI1 or BI6. To conserve animals, results for control hamsters challenged with BI1 or BI6 from the present study and controls from previous identical experiments were combined for statistical comparisons. NTCD strains M3 and T7 achieved 100% colonization and were 100% protective against challenge with BI1 (P ≤ 0.001). M3 colonized 9/10 hamsters and protected against BI6 challenge in the colonized hamsters (P = 0.0003). T7 colonized 10/10 hamsters, but following BI6 challenge, cocolonization occurred in 5 hamsters, 4 of which died, for protection of 6/10 animals (P = 0.02). NTCD colonization provides protection against challenge with toxigenic BI group strains. M3 is more effective than T7 in preventing C. difficile infection caused by the BI6 epidemic strain. Prevention of C. difficile infection caused by the epidemic BI6 strain may be more challenging than that of infections caused by historic BI1 and non-BI C. difficile strains.

Depositional age, provenance, and tectonic and paleoclimatic settings of the late Mesoproterozoic–middle Neoproterozoic Mbuji-Mayi Supergroup, Democratic Republic of Congo

The late Mesoproterozoic–middle Neoproterozoic period (ca. 1300Ma–800Ma) heralded extraordinary climatic and biological changes related to the tectonic changes that resulted in the assembly (~1.0Ga) and the break-up of Rodinia (880Ma–850Ma). In the Democratic Republic of Congo, these changes are recorded in the Mbuji-Mayi Supergroup which was deposited in the SE–NW trending siliciclastic-carbonate failed-rift Sankuru-Mbuji-Mayi-Lomami-Lovoy Basin. New LA-ICP–MS U–Pb laser ablation data on detrital zircon grains retrieved from the lower arenaceous-pelitic sequence (BI group) together with C and Sr isotopic data on carbonates from the upper dolomitic-pelitic sequence (BII group) and an 40Ar/39Ar age determination on a dolerite give a new depositional time frame between 1174±22Ma and ca. 800Ma for the Mbuji-Mayi Supergroup. The upper age limit is based on the assumption that the transition between the BIIb and BIIc subgroups recorded the Bitter Springs anomaly. In terms of tectonic and paleoclimatic settings, the BII group was deposited in the eastern passive margin of the Congo Craton during warm periods interlaced with temporarily dry and wet seasons, suggesting greenhouse conditions during the fragmentation of Rodinia.

Unilateral and bilateral fatiguing contractions similarly alter postural stability but differently modify postural position on bipedal stance

The aim of the present study was to compare the effects of unilateral and bilateral muscle fatigue on bipedal postural control and neuromuscular activities. Nineteen subjects completed bilateral fatiguing contractions (BI group), and seventeen subjects completed unilateral fatiguing contractions (UNI group) of the quadriceps femoris. Postural control, maximal voluntary contraction (MVC) and central activation ratio (CAR) were measured before and after the completion of fatiguing tasks for both groups. Postural control was evaluated by using a force platform, which recorded the center of foot pressure (COP). MVC was quantified with an ergometer and CAR was determined with the superimposed electrical stimulation technique. Spatio-temporal COP parameters were used to evaluate postural stability (displacements of COP) and postural position (coordinates of COP) and a frequency analysis of COP excursions (wavelet transform) was performed to estimate the contribution of different neuronal loops. Postural stability, MVC and CAR were similarly affected after unilateral and bilateral fatiguing contractions. Moreover, the impairment of postural position was higher after unilateral fatiguing contractions than after bilateral fatiguing contractions. The study’s results indicated that unilateral and bilateral fatigue equally disturbs postural control as well as central drive. However, unilateral muscle fatigue creates postural asymmetries while bilateral muscle fatigue does not engender any.

Hepatic resection for bilateral hepatolithiasis: a 20-year experience

There is increasing evidence showing that hepatic resection is probably the best definitive treatment for unilateral hepatolithiasis. However, the role of hepatic resection for bilateral hepatolithiasis is rarely mentioned in the literature. We retrospectively reviewed 197 patients who underwent hepatic resection for hepatolithiasis in Changhua Christian Hospital from December 1987 to December 2007. A total of 156 patients with unilateral hepatolithiasis were defined as the UNI group (control group), and 41 patients with bilateral hepatolithiasis were defined as the BI group (study group). The short- and long-term outcomes were measured. The BI group had longer operating time (200 min versus 173 min, P = 0.006), lower immediate stone clearance rate (56.1% versus 91.7%, P < 0.001), lower final stone clearance rate (75.6% versus 94.9%, P = 0.001), higher rate of stone recurrence (22.6% versus 6.1%, P = 0.009) and higher disease-related mortality (19.5% versus 5.1%, P = 0.006). Thirty patients with bilateral peripheral stones were indicated for bilateral hepatectomy, but only 20 (66.7%) of them actually underwent the proposed procedure. Of the patients who did not achieve immediate stone clearance, bilateral peripheral stones represented 88.9% (P = 0.044). Of the patients who had stone recurrence, patients less than 35 years old represented 42.9% (P = 0.007). Bilateral hepatolithiasis has worse outcomes than unilateral hepatolithiasis after being treated with hepatic resection. Regarding bilateral peripheral stones, there is often a discrepancy between the extent of stone-affected parenchyma and that of final liver resection, resulting in a lower immediate stone clearance rate. A higher stone recurrence rate was observed among younger population.

Protective Effect of Infliximab on Ischemia/Reperfusion-Induced Damage in Rat Kidney

Objective: To investigate the protective effect of infliximab on ischemia–reperfusion (I/R) injury of the rat kidney. Methods: Twenty-eight male Wistar albino rats were divided into four groups: sham-operated, I/R, I/R with infliximab administered before ischemia [I/R + infliximab (bi)], and I/R with infliximab administered before reperfusion [I/R + infliximab (br)]. After a right nephrectomy to produce damage, the left renal vessels were occluded for 60 min, followed by 24-h reperfusion in rats. Changes in the rat kidney were observed by measuring the tissue levels of malondialdehyde (MDA), myeloperoxidase (MPO), glutathione (GSH), and superoxide dismutase (SOD) and by evaluating hematoxylin–eosin (H&E)-stained and periodic acid–Schiff (PAS) sections. Results: The MDA and MPO levels in the I/R group were significantly higher than in the other groups (p < 0.05), and the SOD and GSH levels in the I/R + infliximab (bi) and I/R + infliximab (br) groups were significantly higher than in the I/R group (p < 0.05). However, histological examination revealed that the I/R + infliximab (bi) group and the I/R + infliximab (br) group had significantly fewer tubular changes and interstitial inflammatory cell infiltration than the I/R group. Conclusion: These results show that infliximab may protect against I/R injury in the rat I/R model.

Comparative Susceptibilities to Fidaxomicin (OPT-80) of Isolates Collected at Baseline, Recurrence, and Failure from Patients in Two Phase III Trials of Fidaxomicin against Clostridium difficile Infection

A 10-day course of oral fidaxomicin (200 mg twice a day [b.i.d.]), a potent new macrocyclic drug, was compared to vancomycin (125 mg four times a day [q.i.d.]) in 1,164 adults (1,105 in the modified intent-to-treat [mITT] population) with Clostridium difficile infection in two phase III randomized, double-blind trials at sites in North America and 7 European countries. Of 1,105 mITT patients, 792 (71.7%), including 719/999 (72.0%) in the per-protocol (PP) population, provided a C. difficile strain at baseline, of whom 356 received fidaxomicin with 330 cures (92.7%) and 363 received vancomycin with 329 cures (90.6%). The susceptibilities (MIC(90)) of baseline isolates did not predict clinical cure, failure, or recurrence for fidaxomicin (MIC(90), 0.25 μg/ml for both; range, ≤ 0.007 to 1 μg/ml), but there was a one-dilution difference in the MIC(90) (but not the MIC(50)) for vancomycin (MIC(90), 2 μg/ml [range, 0.25 to 8 μg/ml] for cure and 4.0 μg/ml [range, 0.5 to 4 μg/ml] for failures). A total of 65 (7.9%) "rifaximin-resistant" (MIC > 256 μg/ml) strains were isolated in both treatment groups on enrollment, which increased to 25% for failures at the end of therapy. No resistance to either fidaxomicin or vancomycin developed during treatment in either of the phase III studies, although a single strain isolated from a cured patient had an elevated fidaxomicin MIC of 16 μg/ml at the time of recurrence. All isolates were susceptible to ≤ 4 μg/ml of metronidazole. When analyzed by restriction endonuclease analysis (REA) type, 247/719 (34.4%) isolates were BI group isolates, and the MICs were generally higher for all four drugs tested (MIC(90)s: fidaxomicin, 0.5; vancomycin, 2.0; metronidazole, 2.0; and rifaximin, >256 μg/ml) than for the other REA types. There was no correlation between the MIC of a baseline clinical isolate and clinical outcome. MIC(90)s were generally low for fidaxomicin and vancomycin, but BI isolates had higher MICs than other REA group isolates.

Prospective controlled clinical study on gastric bypass surgery for nonobese type 2 diabetes mellitus

Objective To investigate the efficacy of gastric bypass surgery for the treatment of nonobese type 2 diabetes mellitus. Methods From November 2008 to August 2009, 40 patients with gastric diseases and nonobese type 2 diabetes mellitus were admitted to the Changhai Hospital, and their clinical data were prospectively studied. All patients were randomly divided into 4 groups; 10 patients received Billroth I distal gastrectomy +gastroduodenal anastomosis (BⅠ group) , 10 received proximal gastrectomy + remanant gastric esophageal anastomosis ( PG group), 10 received total gastrectomy + esophagoduodenal Y-anastomosis ( RY group) and 10received subtotal gastrectomy Billroth Ⅱ gastro-jejunostomy (BⅡ group). The length of hospital stay, pre- and postoperative body mass indexes (BMIs) , waist circumferences, levels of fasting blood glucose (FBG) , glycated hemoglobin ( GHbA1) , fasting serum insulin (FSI) and fasting C-peptide (FCP) of patients in the 4 groups were compared. All data were analyzed using analysis of variance, LSD-t test, paired t test or chi-square test. Results The clinical effects of the 4 different operative procedures on the gastric diseases were similar. The levels of FBG were (8.0 ±2.9)mmol/L before operation and (5.9 ±0.7)mmol/L after operation in the RY group, with a significant difference (t = 2. 342, P < 0. 05). The preoperative level of GHbA1 in the RY group was 7.7% ± 1.1%, which was significantly higher than 6. 9% ± 0. 6% at 2 months after the operation and 6. 1 % ± 0. 4% at 6 months after the operation (t = 4. 920, 3.012, P < 0.05). The preoperative level of FCP in the RY group was (1.30 ±0.54) μg/L, which was significantly lower than (1.95 ± 0.86) μg/L at 2 months after the operation and (2.18 ± 0.63)μg/L at 6 months after the operation (t =6. 063, 4. 651, P < 0.05). The levels of FSI in the RY group at postoperative month 1, 2 and 6 were (18 ±5) , (19 ±3) , (21 ±3) mU/L, which were significantly higher than the level of FSI [(11 ±4) mU/L]before operation (t =3. 158, 4. 502, 7. 517, P <0. 05). Preoperative levels of FBG, GHbA1, FSI and FCP in the B Ⅱ group were (8. 3 ± 1. 3) mmol/L, 7. 7% ±0. 9% , (13±4)mU/L and (1.34±0.48) μg/L, which were ignificantly different from (6.7 ± 1.2)mmol/L, 6.8%± 0.8%, (18±4)mU/L and ( 1.68 ±0.46) μg/L at postoperative month 1, (6.4 ± 1.3)mmol/L, 6.3% ±0.6% ,(18±4)mU/L and (1. 96 ± 0. 67) μg/L at postoperative month 2, and (5. 6 ±0. 7) mmol/L, 6.0%±0.3%, (19 ± 4) mU/L and (2.27 ± 0. 59) |μg/L at postoperative month 6 (t = 2. 468, 2. 598, 6. 028; 3. 055, 4. 586,4.572; 3.618, 5.860, 8.577; 2.300, 3.511, 3.943, P<0.05). The levels of FBG,GHbA1 and FCP in the 4 groups at 2 months after surgery were significantly different from those at 6 months after surgery (F = 4. 699,14. 378; 7.411, 29. 192; 3. 335, 9. 334, P < 0.05). The levels of FSI in the 4 groups at different time points were significantly different (F =2. 896, 7. 012, 11. 998, P < 0.05). Conclusion The efficacy of gastric bypass surgery for the treatment of nonobese type 2 diabetes mellitus is satisfactory. Key words: Diabetes mellitus, type 2; Gastric bypass surgery; Clinical controlled trials; Nonobese type

Susceptibility of hamsters to infection by historic and epidemic BI Clostridium difficile strains during daily administration of three fluoroquinolones

Background The recent epidemic of Clostridium difficile infection (CDI) has been attributed largely to the REA strain group BI (aka NAP1/027). Current isolates of the BI group differ from historic non-epidemic BI strains in that they have developed resistance to the newer fluoroquinolone (FQ), moxifloxacin. The acquisition of moxifloxacin resistance has been associated with the rise in frequency of CDI caused by these isolates. In order to explore the effect of FQ resistance on CDI we compared colonization and mortality in hamsters challenged with a historic (BI1 – susceptible to moxifloxacin) and a recent epidemic (BI17 – resistant to moxifloxacin) BI strain of CD during continuous administration of 3 different FQs. Methods Groups of 6 hamsters were treated with a 5 day course of ciprofloxacin, levofloxacin, or moxifloxacin given orally once per day. Each hamster was then challenged with 1 × 10 4 CFU of either BI1 or BI17 on day 3 or day 5. Colonization and time to death were recorded. Results Colonization efficiency (CE) following moxifloxacin (92%) was significantly greater than following levofloxacin (50%, p < 0.01) or ciprofloxacin (42%, p < 0.01) for both strains combined. The CE of BI17 was higher than BI1 for ciprofloxacin (67% vs 17%, p = 0.04) and levofloxacin (83% vs 17%, p < 0.01), but not moxifloxacin (100% and 83%, p = 0.48) administration. BI17 also showed a shorter time from inoculation to death than BI1 following moxifloxacin administration (1.8 days vs 3.9 days, p < 0.01). Moxifloxacin shortened the time from inoculation to death compared to ciprofloxacin in hamsters challenged with BI17 (1.8 days vs 4.0 days, p < 0.01) but not levofloxacin (1.8 days vs 2.0 days, p = NS). Conclusions For the epidemic BI17 strain, ciprofloxacin, levofloxacin and moxifloxacin have similar colonization rates, suggesting that the acquisition of high-level FQ resistance increases colonization rates in association with any FQ. Historic strain BI1 which does not carry high-level FQ resistance colonized efficiently only in the presence of moxifloxacin, possibly explaining lower rates of CDI historically prior to the widespread clinical use of moxifloxacin (and gatifloxacin). Current high rates and severity of CDI from 2000 to 2010 may in part be associated with the acquisition of high-level FQ resistance in BI strains and higher patient exposure rates of all FQs, especially moxifloxacin.

UNILATERAL VERSUS BILATERAL DRAINAGE USING SELF‐EXPANDABLE METALLIC STENT FOR UNRESECTABLE HILAR BILIARY OBSTRUCTION

There is no consensus on the choice of either unilateral or bilateral drainage in stent placement for patients with unresectable hilar biliary obstruction. The aim of the present study was to clarify which drainage method is superior. We retrospectively reviewed 82 patients with hilar biliary obstruction who underwent metallic stenting. These patients were divided into a unilateral drainage group (Uni group) and a bilateral drainage group (Bi group). There was no significant difference between the groups in median survival time, median stent patency period, and median complication-free survival time. The most frequent complication was stent obstruction, followed by cholangitis. Liver abscess was found at a higher frequency in the Bi group (17.6%) than in the Uni group (1.5%) (P=0.0266). There was no significant difference between the groups in the occurrence of two or more complications (P=0.247), life-threatening severe complications (P=0.0577), and stent obstruction by sludge (P=0.0912). When compared with bilateral biliary drainage, unilateral biliary drainage is associated with a lower incidence of liver abscess as well as a comparable outcome of stent patency time and complication-free survival. We therefore propose that hilar biliary obstruction can be treated first by unilateral drainage with a metallic stent and by bilateral drainage only in patients who develop cholangitis in the contralateral biliary tree.

2,4-Dinitrochlorobenzene으로 유도된 아토피 피부염 동물모델에서 비파엽 및 삼백초 추출발효물의 항아토피 활성

본 연구는 in vitro 실험결과 아토피 피부염의 억제 효능이 기대되는 비파엽 추출물(BI군), 삼백초 추출물(SA군), 비파엽 추출물과 삼백초 추출 혼합물(FB군) 그리고 삼백초와 비파엽 추출 혼합 발효물(FA군)을 경구 투여하여 DNCB 처리한 아토피 실험동물을 대상으로 아토피 질환 개선에 대한 유효성을 평가하였다. 혈청 중의 IgE 수치를 측정한 결과, DNCB군에서 227.21±60.04 ng/mL를 나타내었으며, FA군에서는 154.78±78.99 ng/mL로 IgE 생성량이 감소되었다. 혈청내의 히스타민 농도는 DNCB군에서 1.90±0.04 ng/mL였으며, FA, FB, BI, SA군에서 각각 1.47±0.20 ng/mL, 1.41±0.07 ng/mL, 1.61±0.05 ng/mL, 1.08±0.07 ng/mL로 DNCB군과 비교 시 유의적인 감소를 나타내었다. 세라마이드 총 함량을 측정한 결과, FA군에서 1,350±357 μg/g으로 DNCB와 비교 시 세라마이드 함량이 유의적으로 증가되었다. IFN-γ의 경우, DNCB군에서 2.5±0.5 ng/mL로 분석되었으며, FA, FB, BI 및 SA군에서 각각 7.1±1.3 ng/mL, 7.7±0.2 ng/mL, 11.5±0.6 ng/mL 및 6.9±0.2 ng/mL로 DNCB 군과 비교 시 모두 유의적인 증가를 나타내었다. 특히 비파엽 및 삼백초 추출물 혼합 발효물은 등 부위 피부의 육안 증상을 관찰한 결과, 가피형성과 발적 감소가 가장 우수하여 아토피 피부염 질환 개선에 도움을 줄 수 있을 것으로 기대된다.

Molecular Epidemiology ofClostridium difficileover the Course of 10 Years in a Tertiary Care Hospital

The molecular epidemiology of endemic and outbreak Clostridium difficile strains across time is not well known. HindIII restriction endonuclease analysis (REA) typing was performed on available clinical C. difficile isolates from 1982 to 1991. The annual incidence of C. difficile infection (CDI) ranged from 3.2 to 9.9 cases per 1000 discharges and was significantly higher in 1982, 1983, 1985, and 1991 (high-incidence years) than in other years (mean standard deviation number of cases for the high- vs the low-incidence years, 121.8 +/-20.4 and 70.0 +/-15.0; P =.002). A total of 696 (76.6%) of 908 C. difficile isolates were available for REA typing over the 10-year period. Large clusters (>or=10 CDI cases in consecutive months) were caused by REA types B1 and B2 in 1982 and 1983, F2 and B1 in 1985, and K1 in 1991 (high-incidence years). Small clusters of 4-9 CDI cases in consecutive months were caused by REA types G1 (1984), Y4 and Y6 (1987), Y2 (1988), L1 (1989), Y1 (1990), and K1 (1991). Current epidemic REA group BI (unrelated to type B1) was isolated 6 times, twice in 1984, 1988, and 1990. Years with a high incidence of CDI were associated with large clusters of specific REA types that changed yearly. The molecular epidemiology of CDI in this hospital was characterized by a wide diversity of C. difficile types and an ever-changing dominance of specific C. difficile types over time. The current epidemic BI group was found sporadically on 6 occasions. A changing CDI molecular epidemiology should be expected in the future.

Typing and susceptibility of bacterial isolates from the fidaxomicin (OPT-80) phase II study for C. difficile infection

Background Clostridium difficile infection (CDI) has been increasing in incidence and severity in recent years, coincident with the spread of a “hypervirulent” strain, REA type BI (ribotype 027, PFGE NAP 1). Exacerbating the problem has been the observation that metronidazole may be showing decreased effectiveness, particularly in the more severe cases. Fidaxomicin is an 18-membered macrocycle currently in phase 3 trials for the treatment of C. difficile infection (CDI). An open-label, phase II study in CDI patients has been completed and the clinical results published. C. difficile organisms were isolated from patient stool specimens and typed by restriction endonuclease analysis (REA) in order to determine the frequency and susceptibility of the C. difficile isolates and their response to treatment. Methods Fecal samples were plated on CCFA agar for isolation of C. difficile. These isolates were tested for susceptibility to fidaxomicin, vancomycin, and metronidazole using CLSI agar dilution methods and were typed by REA. Results C. difficile was isolated from 38 of 49 subjects and 16 (42%) were the epidemic C. difficile BI group. The BI strain was distributed approximately equally in the three dosing groups. Overall antibiotic susceptibilities were consistent with the previously reported MIC 90 values for the three antibiotics tested, but the MIC 90 of BI strains was two dilutions higher than non-BI strains for metronidazole and vancomycin (for both antibiotics, MIC 90 was 2 μg/mL vs. 0.5 μg/mL, P < 0.01 for metronidazole, P = NS for vancomycin). Clinical cure for BI isolates (11/14, 79%) was not significantly different from non-BI isolates (21/22, 95%). Conclusion These results underscore the high prevalence of the BI epidemic strain and demonstrate that mild to moderate CDI infection as well as severe disease can be caused by these strains. Fidaxomicin cure rates for subjects with BI and with non-BI strains are similar, although the small numbers of subjects preclude a robust statistical comparison.

Raman spectra of isolated and interconnected pyramidal XS3 groups (X = Sb,Bi) in stibnite, bismuthinite, kermesite, stephanite and bournonite

Oriented single-crystals of stibnite, bismuthinite, kermesite, stephanite and bournonite were investigated by polarized Raman spectroscopy. The obtained spectra were compared to those of the sulfosalt minerals tetrahedrite and pyrargyrite. Whereas the latter show isolated SbS 3 groups with ideal trigonal symmetry, the former show distorted XS 3 (X = Sb,Bi) groups with lower symmetry. Moreover, in stibnite and isostructural bismuthinite the pyramidal groups are interconnected to infinite ribbons, and even to sheets in kermesite. The internal vibrations, i.e. the stretching and bending modes, of the SbS 3 groups occur at ~340–180 cm −1 , those of the BiS 3 groups in bismuthinite at ~280–150 cm −1 . The higher mass and the longer bond distances of the BiS 3 groups readily explain the lower wavenumbers of the latter. However, even for the SbS 3 groups a negative correlation between bond distances and vibrational wavenumbers is observed. Moreover, in those minerals with a wide range of pyramidal bond distances, i.e. stibnite, kermesite, bismuthinite, a more extended range of vibrational modes is observed. A clear distinction between Raman spectra of separated and interconnected SbS 3 groups is not observed.

A comparison of sodium bicarbonate infusion versus normal saline infusion and its combination with oral acetazolamide for prevention of contrast-induced nephropathy: a randomized, double-blind trial

Contrast-induced nephropathy (CIN) is commonly encountered. Because the therapy of choice for prevention of CIN is controversial, in this study we compared the preventive efficacy of bicarbonate (Bi) infusion in dextrose water versus normal saline (NLS) infusion alone or in combination with oral acetazolamide (AZ). In a double-blind and randomized clinical trial, all patients undergoing coronary angiography or percutaneous coronary intervention received NLS (NLS group), its combination with AZ (AZ group) or infusion of Bi (Bi group) before the procedures. RIFLE (risk of renal failure, injury to the kidney, failure of kidney function, loss of kidney function, and end-stage renal disease) criteria were used to define CIN-associated acute kidney injury (AKI). The risk of AKI in CIN was significantly lower in the Bi and AZ groups than in the NLS group (P <or= 0.04). Comparing pre-treatment and post-treatment values in each group the following results were obtained: serum creatinine (Scr) increased and eGFR decreased significantly in the NLS group (P = 0.04) and in all patients (P = 0.001, P = 0.02, respectively). In addition, serum potassium decreased significantly in the Bi and NLS groups (P <or= 0.02). Also, serum Bi increased significantly in the Bi group (P = 0.001) whereas it decreased significantly in the AZ group (P = 0.001). Urinary pH also increased in all groups (P <or= 0.04) except the NLS group (P > 0.05). It seems that both Bi and AZ reduce the risk of CIN-related AKI, and close monitoring of serum potassium is needed during bicarbonate infusion.

Cognitive behavior therapy in the treatment of panic disorder

Background:Comprehensive cognitive behavior therapies have been proved to be more effective than behavioral interventions. However, the efficacy of CBT is not studied in the Indian context and also, the amount of change brought about by CBT is not known. Aims: This study aims to examine the efficacy of cognitive behavioral intervention (CBI) in the treatment of panic disorder. Our specific objectives were to assess the effectiveness of CBI in reducing symptom severity as well as cognitions related to panic and panic-related behaviors. Design: The study adopted a two-group comparison with pre- and postassessments design.Materials and Methods:The sample consisted of 30 patients sequentially allotted to the CBI (n = 15) and behavioral intervention (BI, n = 15) groups. Assessment was done using a semistructured interview schedule, panic disorder severity scale, Texas panic attack record form, Anxiety Sensitivity Index, Agoraphobic cognitions questionnaire, Behavioral avoidance checklist, and Panic appraisal inventory. The CBI group was provided with comprehensive cognitive behavior therapy and the BI group with psycho-education and applied relaxation.Results:CBI was found to be superior to BI in the reduction of panic symptoms, behavioral avoidance, safety behaviors, and cognitions. A large percentage of the CBI group patients met the criteria for clinically significant change with a large magnitude of change.Conclusion:Multicomponent CBI is superior to BI in terms of the amount of change it brings about with respect to panic symptoms, avoidance, safety behaviors, and cognitions.

Application of erosion-control materials and spontaneous vegetation in the protection of reservoirs in southern and eastern Serbia

The quality and stability of erosion-control materials in protection of reservoirs in Southern and Eastern Serbia have been examined both in the field and in accredited laboratories in our country. Field investigations have been carried out over a period of 15 years in Eastern Serbia and for up to 30 years in Southern Serbia, and they are still being conducted by monitoring the state and possible damage of consolidation-retention check dams, walls, and other erosion-control structures. The materials used in protection of the Selova and Grliste Reservoirs are typical construction materials, such as resistant natural stone, concrete of the BI group, i.e., MB 20, aggregate, synthetic elements, etc. Long-term monitoring of their state and minor deformations has shown that the materials were well-chosen and stable, and that there has been no significant damage, except for some minor crumbling and smaller cracks due to negligible scouring. This is all the result of prior thorough empirical and laboratory testing of applied materials, which helped to achieve stability and functionality of structures erected to prevent silting-up of the reservoir. Such a state has contributed to stabilization of erosion processes and reduction of sediment quantities, improvement of water quality, and advancement of the autochthonous vegetation (Salix L., Cornus L., Quercus L.). Vegetation has further mitigated erosion, decreased floods, and consolidated the structures, thereby improving the ecological quality of the catchments as well as the entire study area.

Impact of electrical shock waveform and paddle positions on efficacy of direct current cardioversion for atrial fibrillation

Direct-current electrical cardioversion is the main method for the conversion of atrial fibrillation. Its success depends on many factors. In several studies, biphasic shock waveforms have been demonstrated to be superior to monophasic shocks for termination of atrial fibrillation; however, information about impact of paddle position is controversial. Initial energy level is an object of discussions. The aim of the study was to compare a truncated exponential biphasic waveform with monophasic damped sine waveform and antero-lateral with antero-posterior paddle positions for cardioversion of atrial fibrillation, to determine its impact on early reinitiation of atrial fibrillation. A total of 224 consecutive patients with atrial fibrillation underwent electrical cardioversion with biphasic (Bi, n=112) or monophasic (Mo, n=112) shock waveform in a randomized fashion. The position of hand-held paddle electrodes was randomly selected in both groups to be anterior-lateral and anterior-posterior. Energies used were 100-150-200-300-360 J (Bi) or 100-200-300-360 J (Mo). If monophasic shock of 360 J was ineffective, we used biphasic shock of 360 J. Early recurrent atrial fibrillation (ERAF) was defined as a relapse of atrial fibrillation within 2 min after a successful cardioversion, acute recurrent - within 24 h. Two study groups (Bi vs Mo) did not differ with regard to age, body mass index, duration of AF episode (mean 98+/-147 days for the Bi group and 80+/-93 days for the Mo group, P=0.26), underlying heart disease, left atrial diameter, left ventricular ejection fraction. In the Mo group, more patients used amiodarone (59.82% vs 41.97%, P=0.002), in the Bi group more patients used propafenone (16.07% vs 8.93%, P=0.033). Cardioversion success rate was 97.32% in the Bi group and 79.46% in the Mo group (P<0.001). After biphasic shock of 360 J in Mo group, the cumulative success rate was 99.11%. Mean delivered energy and mean number of shocks were significantly lower in the Bi group (198.5+/-204.4 J, 1.5+/-0.9 shocks vs 489.1+/-464.2 J, 2.4+/-1.5 shocks). The efficacy of first shock was 66.96% in the Bi group and 37.5% in the Mo group (P<0.0001). Incidence of ERAF was 4.46% in both groups. Paddle position had no impact on efficacy of cardioversion and ERAF. For the cardioversion of atrial fibrillation, biphasic shock waveform has a higher success rate than monophasic shock waveform. We did not observe the influence of paddle positions on efficacy of cardioversion. Shock waveform and paddle position had no impact on ERAF. We recommend starting with biphasic energy of 150 J and monophasic of not less than 200 J for cardioversion of atrial fibrillation.