Sodium thiosulfate-based treatment in calcific uremic arteriolopathy: a consecutive case series

BACKGROUND

Calcific uremic arteriolopathy (CUA) is a rare complication in end stage renal disease with high mortality. Numerous case reports and one case series of 3 patients report the benefit of sodium thiosulfate (STS) for treatment of CUA. The purpose of this evaluation was to examine the response to a STS-based treatment approach in patients with CUA with 1 year follow up.

METHODS

A retrospective case series of 6 consecutive patients from Manitoba, Canada who met predefined diagnostic criteria for CUA and received STS between 2006 and 2008 were included. STS responders were defined as improvement in at least one of the following three parameters: pain severity, wound size and diagnostic imaging/radiography. Mortality, STS dose, duration, adverse events and cost were also collected.

RESULTS

Four patients were classified as responders. The 2 responders who survived at 1 year of follow-up demonstrated an improvement in all 3 parameters examined including an improvement in their follow-up diagnostic imaging results within the first 4 - 6 weeks of STS treatment. At 1 year of follow-up, 3 patients died.

CONCLUSION

Using an STS-based multifaceted treatment approach for CUA, 4 patients responded but 3 of 6 patients died within 1 year. Further larger prospective studies are needed to delineate STS responders from non-responders.

Usefulness of resistant gene markers for predicting treatment outcome on second-line anti-tuberculosis drugs

AIM

Mutations in rrs [nucleotide (nt) 1401], gyrA gene (codons 90, 91 or 94), tlyA, ethA and thyA genes of Mycobacterium tuberculosis (MTB) were evaluated for their usefulness in predicting treatment outcome of kanamycin (KM), capreomycin (CPM), ofloxacin (OFX), ethionamide (ETH) and para-aminosalicylic acid (PAS).

METHODS AND RESULTS

DNA sequence analyses of these genes were performed against 188 MTB isolates obtained from patients put on second-line anti-TB drugs (SLDs) with well-documented clinical history and treatment outcome. Mutations in rrs and gyrA have 100% positive predictive value (PPV) in predicting treatment failure for KM and OFX, while 88·9 and 80% were obtained, respectively, when tlyA and rrs mutations were considered in CPM. For ETH and PAS, the PPV of using ethA and thyA mutations to predict treatment failure was 82·5 and 89·3%, respectively.

CONCLUSIONS

Our study demonstrated high specificities of gene mutations in predicting poor treatment outcome; however, further technical advancement is required to make the molecular detection of resistances to other SLDs feasible in clinical laboratories.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first study to correlate different polymorphisms of major SLD resistance gene markers with predicted treatment outcome, using an international set of well-documented clinical MTB strains.

Symbiotic Characteristics of Rhizobium leguminosarum bv. trifolii Isolates Which Represent Major and Minor Nodule-Occupying Chromosomal Types of Field-Grown Subclover (Trifolium subterraneum L.)

The symbiotic effectiveness and nodulation competitiveness of Rhizobium leguminosarum bv. trifolii soil isolates were evaluated under nonsoil greenhouse conditions. The isolates which we used represented both major and minor nodule-occupying chromosomal types (electrophoretic types [ETs]) recovered from field-grown subclover (Trifolium subterraneum L.). Isolates representing four ETs (ETs 2, 3, 7, and 8) that were highly successful field nodule occupants fixed between 2- and 10-fold less nitrogen and produced lower herbage dry weights and first-harvest herbage protein concentrations than isolates that were minor nodule occupants of field-grown plants. Despite their equivalent levels of abundance in nodules on field-grown subclover plants, ET 2 and 3 isolates exhibited different competitive nodulation potentials under nonsoil greenhouse conditions. ET 3 isolates generally occupied more subclover nodules than isolates belonging to other ETs when the isolates were mixed in 1:1 inoculant ratios and inoculated onto seedlings. In contrast, ET 2 isolates were less successful at nodulating under these conditions. In many cases, ET 2 isolates required a numerical advantage of at least 6:1 to 11:1 to occupy significantly more nodules than their competitors. We identified highly effective isolates that were as competitive as the ET 3 isolates despite representing serotypes that were rarely recovered from nodules of field-grown plants. When one of the suboptimally effective isolates (ET2-1) competed with an effective and competitive isolate (ET31-5) at several different inoculant ratios, the percentages of nodules occupied by the former increased as its numerical advantage increased. Although subclover yields declined as nodule occupancy by ET2-1 increased, surprisingly, this occurred at inoculant ratios at which large percentages of nodules were still occupied by ET31-5.

Serological and Ecological Characteristics of a Nodule-Dominant Serotype from an Indigenous Soil Population of Rhizobium leguminosarum bv. trifolii

Although at least 13 antigenically distinct serotypes of Rhizobium leguminosarum bv. trifolii exist in an Abiqua silty clay loam soil, one serotype, AS6, occupies >/=50% of the root nodules formed on field-grown subclover and between 33 and 78% of the nodules formed on five annual clover species grown in the same soil under laboratory conditions. The dominance of subclover nodules by serotype AS6 was reproducible over a 4-year sampling period and throughout the entire 200- by 100-m pasture examined. Serotype AS6 was composed of three antigenically distinct subtypes (AS6-a, AS6-b, and AS6-c). Each subtype contributed about one-third of the AS6 isolates recovered from nodules of field-grown subclover plants and maintained similar population densities in nonrhizosphere and rhizosphere soil. Rhizobia with the AS6 antigenic signature accounted for from 20 to 100% of the soil populations of R. leguminosarum in arable and pasture soils under legumes throughout the state of Oregon. Over a 12-month period, the population densities of the serotype AS6 complex and three minor nodule-occupying serotypes (AG4, AP17, and AS21) were measured in the rhizospheres of field-grown subclover and orchard grass and in nonrhizosphere Abiqua soil. Regardless of season or serotype, the orchard grass rhizosphere effect was minimal, with the ratio between rhizosphere and nonrhizosphere serotype population densities ranging between 2.5 (midsummer) and 10.5 (spring). In contrast, the magnitude of the subclover rhizosphere effect varied seasonally and among serotypes. Between October and December the ratios for all serotypes were similar (12.5 to 25.5). However, in the spring (April and May), the magnitude of the rhizosphere effect varied among the indigenous serotypes (ratios, 10.5 to 442) and for minor nodule-occupying serotypes AS21 (ratio, 442) and AP17 (ratio, 47) was as great as, or even greater than, the magnitude of the rhizosphere effect observed with the AS6 complex (ratio, 65.5).

Toward orthogonal non-individualised head-related transfer functions for forward and backward directional sound: cluster analysis and an experimental study

Individualised head-related transfer functions (HRTFs) have been shown to accurately simulate forward and backward directional sounds. This study explores directional simulation for non-individualised HRTFs by determining orthogonal HRTFs for listeners to choose between. Using spectral features previously shown to aid forward-backward differentiation, 196 non-individualised HRTFs were clustered into six orthogonal groups and the centre HRTF of each group was selected as representative. An experiment with 15 listeners was conducted to evaluate the benefits of choosing between six centre-front and six centre-back directional sounds rather than the single front/back sounds produced by MIT-KEMAR HRTFs. Sound localisation error was significantly reduced by 22% and 65% of listeners reduced their front-back confusion rates. The significant reduction was maintained when the number of HRTFs was reduced from six to five. This represents a preliminary success in bridging the gap between individual and non-individual HRTFs for applications such as spatial surround sound systems. STATEMENT OF RELEVANCE: Due to different pinna shapes, directional sound stimuli generated by non-individualised HRTFs suffer from serious front-back confusion. The reported work demonstrates a way to reduce front-back confusion for centre-back sounds generated from non-individualised HRTFs.

Freezing inactivation of Escherichia coli and Enterococcus faecalis in water: response of different strains

The effect of freezing temperature (-7, -15, -30 and -80 degrees C), number of freeze/thaw cycles (1 to 5 cycles) and sample volume (100 mL and 100 microL) on the viability of a pathogenic and an opportunistically pathogenic Escherichia coli, a vancomycin-resistant and a vancomycin-sensitive Enterococcus faecalis were examined. About 3.3 to 4.3 and 1.5 to 2.4 log reduction in cell density were observed in E. coli and E. faecalis, respectively, in the 100 mL samples frozen at -30 degrees C or warmer. Freezing at -80 degrees C was the least effective in killing the microbes, on average the log reduction at -80 degrees C was approximately 1.0 to 1.5 units less than those achieved at the three warmer temperatures. Based on statistical analysis, cell inactivation levels achieved at -7, -15, or -30 degrees C were not significantly different (P-value = 0.1648). There were no statistical difference in terms of log reduction obtained under all experimental conditions for the two E. coli strains (P-value = 0.46) and the two E. faecalis strains (P-value = 0.10). The number of freezing/thaw cycles and sample volume, however, profoundly affected inactivation capacity of freezing. Freezing could be an effective method for further reduction of E. coli and Enterococcus in municipal wastewater/sludge.

Open access colonoscopy in the training setting: which factors affect patient satisfaction and pain?

BACKGROUND AND STUDY AIM

Patient satisfaction with colonoscopy is important for quality assurance; it may be affected by various factors, including patient characteristics, physician training level, and procedural or organizational features. We aimed to analyze how these factors influenced patient satisfaction and pain in an outpatient training setting.

METHODS

Consecutive patients for open access colonoscopy (OAC) were enrolled in a prospective, single-blinded, controlled study. Primary and secondary outcomes were satisfaction and pain scores with and without trainee participation. A multivariate analysis was designed to achieve an 80 % power with an alpha value of 0.05.

RESULTS

368 patients were enrolled. Satisfaction with the procedure was high (mean score 1.36; 1 = best to 5 = worst). In the multivariate analysis only waiting time in the endoscopy suite was significantly associated with lower satisfaction scores ( P = 0.024). Satisfaction was unaffected by patient factors (gender, American Society of Anesthesiologists' [ASA] score, anxiety, etc). Higher pain scores were associated with higher anxiety levels ( P = 0.02), female gender ( P = 0.02), longer procedure ( P< 0.001), and lower sedation levels ( P = 0.001); trainee involvement (49 % of procedures) did not adversely affect satisfaction or pain scores.

CONCLUSIONS

Patient satisfaction with OAC using sedation appears to depend primarily on organizational factors (waiting time beforehand). In contrast, pain is associated with patient characteristics (female gender, anxiety) and procedural factors (lower sedation, longer procedure). Trainee participation did not affect satisfaction or pain scores, a finding which may help to reassure patients undergoing OAC with trainee participation.

Neuropathogenesis of chimeric simian/human immunodeficiency virus infection in pig-tailed and rhesus macaques

We recently reported that a chimeric simian/human immunodeficiency virus (SHIVKU-1) developed in our laboratory caused progressive depletion of CD4+ T lymphocytes and AIDS within 6 months of inoculation into pig-tailed macaques (M. nemestrina). None of the pig-tailed macaques showed productive SHIV infection in the central nervous system (CNS). In this report, we show that by further passage of the pathogenic virus in rhesus macaques [M. mulatta], we have derived a new strain of SHIV (SHIVKU-2) that has caused AIDS and productive CNS infection in 3 of 5 rhesus macaques infected with the virus. Productive replication of SHIV in the CNS was clearly shown by high infectivity titers and p27 protein levels in brain homogenates, and in 2 of the 3 rhesus macaques this was associated with disseminated, nodular, demyelinating lesions, including focal multinucleated giant cell reaction, largely confined to the white matter. These findings were reminiscent of HIV-1 associated neurological disease, and our immunohistochemical and in situ hybridization data indicated that the neuropathological lesions were associated with the presence of SHIV-specific viral antigens and nucleic acid respectively. However, the concomitant reactivation of opportunistic infections in these macaques suggested that such pathogens may have influenced the replication of SHIV in the CNS, or modified the neuropathological sequelae of SHIV infection in the rhesus species, but not in pig-tailed macaques. Our findings in the two species of macaques highlight the complexities of lentiviral neuropathogenesis, the precise mechanisms of which are still elusive.

Treatment of hepatitis B with lamivudine and tenofovir in HIV/HBV-coinfected patients: factors associated with response

As therapy for human immunodeficiency virus (HIV) infection evolves, optimizing hepatitis B virus (HBV) treatment and identifying factors that impact its response in the HIV/HBV-coinfected population is critical. We identified retrospectively 45 HBV/HIV-coinfected patients with detectable HBV DNA by the Bayer VERSANT HBV 3.0 bDNA assay (limit of quantification 2000 copies/mL) at baseline and/or year 1 of therapy. Patients were divided into three groups based on the active HBV agent in their antiretroviral regimen: group 1 (n = 15) received lamivudine; group 2 (n = 10), lamivudine plus tenofovir and group 3 (n = 20), lamivudine followed by lamivudine plus tenofovir. HBV genotypes and resistance profiles were determined by the Bayer Trugene HBV 1.0 assay. More patients in group 2 achieved HBV DNA suppression below 2000 copies/mL (80%), loss of HBe antigen (HBeAg) (40%) and loss of HBeAg and gain of anti-HBe (20%) than did patients in group 1 or 3. More patients with HBV genotype A, achieved HBV DNA suppression <2000 copies/mL than did patients with non-A genotypes [74% (26/35) vs 20% (2/10)], respectively (P = 0.003). Risk for virological nonresponse was significant in those with non-A genotypes [odds ratio (OR) 11.1; 95% CI: 2.0-50], previous HIV therapy (OR 6.5; 95% CI: 1.2-35) and <90% compliance (OR 3.7; 95% CI: 0.99-14.3). Simultaneous therapy with lamivudine/tenofovir suppresses HBV DNA more effectively than lamivudine or tenofovir added to lamivudine. More patients infected with HBV genotype A responded than the non-A patients, regardless of therapeutic regimen, compliance or prior HIV therapy.

A low cost, non-individualized surround sound system based upon head related transfer functions: an ergonomics study and prototype development

This paper reports on the types and magnitudes of localization errors of simulated binaural direction cues generated using non-individualized, head-related transfer functions (HRTFs) with different levels of complexity. Four levels of complexity, as represented by the number of non-zero coefficients of the associated HRTF filters (128, 64, 32, 18 non-zero coefficients), were studied. Experiment 1 collected 1728 data runs that were exhaustive combinations of the four levels of complexity, nine simulated directions of sound (no direction (i.e., diotical-mono), 0 degrees , 45 degrees , 90 degrees , 135 degrees , 180 degrees , 225 degrees , 270 degrees , and 315 degrees azimuth angles at 0 degrees elevation), two repetitions, and 24 participants). Binaural cues generated from HRTFs of reduced complexity (from 128 to 18 non-zero coefficients) produced significantly higher localization errors for the directions of 45 degrees , 135 degrees , 225 degrees , and 315 degrees azimuth angles (p<0.01). From the directions of 0 degrees , 90 degrees , and 270 degrees azimuth angles, the cues produced by HRTFs with reduced complexity did not affect the localization error (p>0.2). Surprisingly, cues produced by HRTFs of 128 non-zero coefficients did not have the lowest number of errors. From 45 degrees , 135 degrees , 225 degrees , and 315 degrees , the lowest numbers of errors were obtained from cues produced by HRTFs of 64, 32, 32, and 64 non-zero coefficients, respectively. Based on these findings, a prototype virtual headphone-based surround-sound (VHSS) system was developed. A double-blind usability experiment with 32 participants indicated that the prototype VHSS system received significantly better surround-sound ratings than did a Dolby stereo system (p<0.02). This paper reports results from an original ergonomics study and the application of these results to the design of a consumer product.

Laparoscopic total colectomy for colorectal cancers: a comparative study

BACKGROUND

No previous report could be found in the literature comparing laparoscopic and open total colectomy for colorectal cancers, especially synchronous colorectal cancers. This study aimed to compare the short-term clinical outcomes and oncologic results of laparoscopic and open total colectomy or proctocolectomy for colorectal cancers.

METHODS

Between July 1997 and January 2005, six patients with colorectal cancers underwent elective laparoscopic total colectomy or proctocolectomy at the authors' institution. Clinical data for 12 patients who underwent elective open total colectomy or proctocolectomy for colorectal cancers during the same period were prospectively collected and compared.

RESULTS

The median follow-up periods were 43.9 months for the laparoscopic group and 48.2 months for the open group. Conversion to open procedure was required for one patient (16.7%) in the laparoscopic group because of bleeding. The median operative time was significantly longer in the laparoscopic group (427.5 min; range, 280-480 min vs 172.5 min; range, 90-260 min; p = 0.001). The patients in the laparoscopic group required a significantly shorter duration of parenteral analgesia (3 vs 5 days; p = 0.01), but there were no differences in time to first bowel motion, time to resumption of diet, time to full ambulation, and duration of hospital stay between the two groups. Perioperative morbidity rates were comparable between the two groups, and there was no operative mortality. The oncologic results, including number of lymph nodes removed, recurrence rates, and survival rates, were similar in the two groups.

CONCLUSIONS

Laparoscopic total colectomy has short-term clinical outcomes (postoperative recovery and perioperative morbidity and mortality rates) and oncologic results similar to those of open surgery for treating patients with colorectal cancers. Our study has shown that the only advantage of laparoscopic over open surgery is a shorter duration of analgesic requirement, but at the expense of a longer operative time.

Denaturing HPLC for high-throughput screening of rifampicin-resistant Mycobacterium tuberculosis isolates

OBJECTIVE

To evaluate the use of denaturation high-performance liquid chromatography (dHPLC) as a rapid method to detect rifampicin (RMP) resistance based on mutations in the rpoB gene in a high-volume laboratory setting.

METHODS

A total of 132 RMP-resistant Mycobacterium tuberculosis strains with different rpoB mutation were used to optimise the running condition of dHPLC as a pilot study. A blind correlation study was subsequently done between dHPLC and in vitro RMP susceptibility tests on 3167 M. tuberculosis strains in a high-throughput clinical setting.

RESULTS

In the pilot study, rpoB mutation could be detected on 116/132 (87.9%) RMP-resistant strains by dHPLC. In the second phase of the study, 84/3107 (2.7%) clinical M. tuberculosis isolates were RMP-resistant. The sensitivity and specificity of dHPLC in the prediction of RMP resistance were 70/84 (83.3%) and 70/77 (91.0%), respectively. The specificity became 100% when 511 Leu to Pro mutation was excluded from the RMP resistance-related genetic changes.

CONCLUSION

In the detection of RMP resistance in a high-throughput laboratory setting, dHPLC has been demonstrated to be rapid, simple, workable, automatable and inexpensive in terms of running costs and the labour involved.

Treatment of atrophic vaginitis with topical conjugated equine estrogens in postmenopausal Asian women

OBJECTIVE

We investigated the effects of 2 months of treatment with topical estrogens on atrophic vaginitis and gynecological health in Asian women.

STUDY DESIGN

Multicenter, open-label trial of 150 postmenopausal women age <70 years with atrophic vaginitis. Women applied conjugated equine estrogens (CEE) vaginal cream (0.625 mg/g) once daily on days 1-21 of two 28-day cycles. Changes in the vaginal maturation index (VMI) from baseline to days 21 (month 1) and 49 (month 2) were the primary outcome. Physiological changes were assessed by the Genital Health Clinical Examination (GHCE).

RESULTS

The VMI was significantly improved (p < 0.001) from baseline at each assessment period. The significant improvement in GHCE from baseline after 1 month (p < 0.001) was maintained at 2 months.

CONCLUSIONS

Vaginal treatment with CEE cream for 21 days of two consecutive 28-day cycles resulted in beneficial changes in the vaginal tissues and induced an overall genital health pattern more characteristic of the premenopausal state.

Prediction of vocational outcome of people with brain injury after rehabilitation: a discriminant analysis

Due to advancements in emergency evacuation procedures and neurosurgical techniques, more patients with brain injury (BI) can survive cerebral injury and regain a satisfactory degree of recovery through rehabilitation. Their improvement in physical and cognitive functions can facilitate their reintegration into the community, especially their return to work (RTW). Different factors were reported to affect this rate of RTW in previous studies. This retrospective study thus aimed to investigate the role of demographic data, the severity of injury, residual physical deficits, activities of daily living, and cognitive function using a stepwise discriminant function analysis (DFA). Data sets for 79 persons with BI were retrieved so as to identify predictors of their vocational outcomes upon discharge and during a follow-up period. The stepwise DFA revealed that the discharge score on the Disability Rating Scale (DRS), the attention-subtest of the Neurobehavioral Cognitive Status Examination (NCSE) or Cognistat, and pre-morbid occupation were significant predictors that correctly classified 65.8% of the subjects.

Over-expression of Bcl-2 against Pteris semipinnata L-induced apoptosis of human colon cancer cells via a NF-kappa B—related pathway

Ent-11 alpha-hydroxy-15-oxo-kaur-16-en-19-oic-acid (5F), an antitumor component, is a chemical compound isolated from Pteris semipinnata L (PsL), a Chinese traditional herb. We examined whether 5F could affect apoptosis in human colon cancer HT-29 cells, and test whether and how the over-expression of Bcl-2 and Bcl-xL could offset the effect of 5F on cell growth. The result demonstrated that 5F significantly induced apoptosis of HT-29, as shown by MTT assay and DNA fragmentation measurement. Treatment of HT-29 with 5F increased both p38 and iNOS levels, suggesting these two molecules may contribute to the apoptotic effect of 5F. Over-expression of Bcl-2 or Bcl-xL attenuated the increase of p38 and iNOS induced by 5F. The cells with Bcl-2 or Bcl-xL over-expression showed an elevation of nuclear factor kappa B (NF-kappa B) activity, accompanying a significant reduction of 5F-induced apoptosis. Furthermore, inhibition of NF-kappa B by I k B alpha SR, which is a powerful inhibitor of NF-kappa B, restored the ability of 5F to induce apoptosis in the cells transfected with Bcl-2. These data strongly indicated that the apoptotic effect of 5F on HT-29 was closely associated with the activity of NF-kappa B, which was up-regulated by Bcl-2 and Bcl-xL. In conclusion, 5F induced apoptosis in HT-29 cells and this apoptotic effect was associated with the high level of p38 and iNOS expression. The apoptotic effect of 5F could be significantly offset by over-expression of either Bcl-2 or Bcl-xL. Bcl-2, and to the less extent, Bcl-xL, were able to increase the activity of NF-kappa B, which was a known anti-apoptotic molecule in human colon cancer cells.

Lymphocyte subsets and natural killer cell cytotoxicity after laparoscopically assisted resection of rectosigmoid carcinoma

BACKGROUND

Laparoscopically assisted resection of colorectal carcinoma is technically feasible and minimally invasive. Postoperative immunosuppression also may be reduced. This study compared the lymphocyte subsets and natural killer (NK) cell cytotoxicity in patients after laparoscopically assisted resection with those after open resection of rectosigmoid carcinoma.

METHODS

In this study, 40 patients with rectosigmoid carcinoma, but no evidence of metastasis, were randomized to receive either laparoscopically assisted or conventional open resection of the tumor. Blood was collected before the operation, then 24 h, 72 h, and 8 days after the operation for studies of lymphocyte subsets and NK cell cytotoxicity.

RESULTS

The lymphocyte subsets and NK cell cytotoxicity of both groups showed typical suppression after surgery. The suppression of T cell activation and NK-like T cells was significantly less after laparoscopically assisted resection than in after open resection, whereas the difference in other lymphocyte subsets and NK cell cytotoxicity was not significant.

CONCLUSION

This study showed that some cellular components of the immune system are less suppressed after laparoscopically assisted than after conventional open resection of rectosigmoid carcinoma. This may have implications for tumor recurrence and long-term patient survival.

Feasibility study of using air as a contrast medium in MR colonography

AIM

To evaluate the feasibility of using air as intraluminal contrast medium in magnetic resonance (MR) colonography.

MATERIALS AND METHODS

Twenty-two patients underwent MR colonography (MRC) using air before colonoscopy. All patients were imaged in prone and supine positions. Each colon was divided into five segments. Two radiologists reviewed the images for the degree of colonic distension, image quality and colonic lesions. The colonic lesions identified using MR were compared with those identified on colonoscopy.

RESULTS

Eight men and 14 women with mean age of 55.5 years were studied. All patients completed the MR examination. One hundred and five out of 110 (95.5%) colonic segments were well distended in both prone and supine positions. Image quality was good in all cases. Colonoscopy detected 16 lesions: three > or = 1 cm, one 7 mm lesion and 12 lesions < or = 5 mm. All lesions 1 cm or larger were detected by MRC.

CONCLUSION

MRC using air and the single-shot half-Fourier rapid acquisition with refocused echoes (RARE) technique is feasible. But in this small pilot study, it had low sensitivity for the detection of polyps less than 1 cm in diameter.