Assessing the biological efficacy and rate of recontamination following hydrogen peroxide vapour decontamination

The inanimate hospital environment can become contaminated with nosocomial pathogens. Hydrogen peroxide vapour (HPV) decontamination has proven effective for the eradication of persistent environmental contamination. We investigated the extent of meticillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE) and gentamicin-resistant Gram-negative rod (GNR) contamination in a ward side-room occupied by a patient with a history of MRSA, VRE and GNR infection and colonisation and investigated the impact of HPV decontamination. Fifteen standardised sites in the room were sampled using a selective broth enrichment protocol to culture MRSA, VRE and GNR. Sampling was performed before cleaning, after cleaning, after HPV decontamination and at intervals over the subsequent 19 days on two separate occasions. Environmental contamination was identified before cleaning on 60, 30 and 6.7% of sites for MRSA, GNR and VRE, respectively, and 40, 10 and 6.7% of sites after cleaning. Only one site (3.3%) was contaminated with MRSA after HPV decontamination. No recontamination with VRE was identified and no recontamination with MRSA and GNR was identified during the two days following HPV decontamination. Substantial recontamination was identified approximately one week after HPV decontamination towards post-cleaning levels for GNR and towards pre-cleaning levels for MRSA. HPV is more effective than standard terminal cleaning for the eradication of nosocomial pathogens. Recontamination was not immediate for MRSA and GNR but contamination returned within a week in a room occupied by a patient colonised with MRSA and GNR. This finding has important implications for the optimal deployment of HPV decontamination in hospitals.

Acute Myelogeneous Leukemia (M0/M1) with novel chromosomal abnormality of t(14;17) (q32; q11.2)

Acute Myelogeneous Leukemia (AML) is a heterogeneous disease with respect to morphology, immunophenotype, and genetic rearrangements. Multiple recurrent chromosomal aberrations have been identified by conventional cytogenetic analysis. In this study, we report a case whose clinical features were suggestive of AML-M1 subtype with t(14;17) (q32; q11.2) karyotype involving rearrangement of chromosomal segments 17q11.2 and 14q32. This is the first report of novel chromosomal translocation in this subset of AML and has not yet been reported elsewhere. This rearrangement may include certain cancer associated oncogene(s) or genes involved in the differentiation like retionic acid receptor alpha (RARA), which may confer differentiation blockage and/or proliferation advantage.

Perception of African American men of their likelihood of a cancer diagnosis at the time of prostate biopsy

6503

Background: Men are supposed to have an “informed discussion” before undergoing PCa screening. African Americans (AA) are diagnosed at later stages of prostate cancer (PCa) than their white counterparts. We studied racial differences in self-prediction compared with actual likelihood of positive biopsy. Method: Face-to-face surveys with patients (n = 172), referred after screening positive for possible PCa, were conducted in urology clinics at the time of biopsy. The surveys include socio-demographics, general anxiety (Hospital Anxiety and Depression Scale), disease-specific anxiety (Memorial Anxiety Scale for Prostate Cancer), and self-estimated likelihood of a positive biopsy. Medical records were reviewed for biopsy results. Results: Average age was 63±7.9, AA comprised 39% of the sample, and 56% had at least a college degree. The overall rate of positive biopsy was 55%, with AA being much more likely to have a positive biopsy (70% vs. 44%; p< 0.05). Despite being referred for biopsy for concern about PCa, 37% of the men indicated that they had a 0% likelihood of having prostate cancer (i.e. that it was impossible), and AA were more likely than whites to say this (58% vs. 24%; p < 0.01). In a logistic regression with important covariates, patients’ ratings of their likelihood of PCa diagnosis were not predictive of a positive biopsy, while older age, higher PSA score, and lower self-rated health were. Generalized anxiety was not correlated with estimated likelihood of having PCa, but cancer-specific anxiety was correlated (p = 0.02). Neither was correlated with likelihood of having PCa. Conclusion: AA are more likely to have PCa at biopsy than whites. Both groups dramatically underestimate their statistical likelihood of having PCa at the time of biopsy. More concerning, AA estimates are lower, yet their likelihood is higher.

No significant financial relationships to disclose.

Curiethérapie utérovaginale de bas débit pulsé: influence du support dosimétrique

PURPOSE

To evaluate two dosimetric supports used in pulse dose rate brachytherapy (PDR): coverage of target volumes, dose to organs at risk, residual tumor after surgery, survival.

PATIENTS AND METHODS

Twenty patients treated for uterine cervix tumor first by brachytherapy PDR had a dosimetric CT-scan after implantation. For 9 patients, the treatment was planned from standard radiographies and then reported on CT-scan images. For 11 patients, it was directly planned from CT-scan. Six weeks after, 18 patients underwent surgery.

RESULTS

With a median follow-up of 22 months, 2 year actuarial survival was 89%. Six patients developed grade II urinary or gynecological complications (LENT SOMA scale). No residual tumor was found for 12 patients (7 with a 3D treatment and 5 a 2 D treatment). Ninety-five percent of CTVHR received 53 Gy (2D treatment) or 63 Gy (3D treatment). Two cm3 of bladder wall received 63 Gy (2D) or 74 Gy (3D) although 2 cm3 of rectal wall received 37 Gy (2D) and 35 Gy (3D).

CONCLUSION

Using CT-scan made us improve the coverage of the uterine cervix but increase the dose received by the bladder, without increasing the rate of histological remission after surgery. We should be prudent before changing our practice.

An algorithm for the management of bile leak following laparoscopic cholecystectomy

INTRODUCTION

The management of bile leaks following laparoscopic cholecystectomy has evolved with increased experience of ERCP and laparoscopy. The purpose of this study was to determine the impact of a minimally invasive management protocol.

PATIENTS AND METHODS

Twenty-four patients with a bile leak following laparoscopic cholecystectomy were recorded consecutively between 1993 and 2003. Between 1993-1998, 10 patients were managed on a case-by-case basis. Between 1998-2003, 14 patients were managed according to a minimally invasive protocol utilising ERC/biliary stenting and re-laparoscopy if indicated.

RESULTS

Bile leaks presented as bile in a drain left in situ post laparoscopic cholecystectomy (8/10 versus 10/14) or biliary peritonitis (2/10 versus 4/14). Prior to 1998, neither ERC nor laparoscopy were utilised routinely. During this period, 4/10 patients recovered with conservative management and 6/10 (60%) underwent laparotomy. There was one postoperative death and median hospital stay post laparoscopic cholecystectomy was 10 days (range, 5-30 days). In the protocol era, ERC +/- stenting was performed in 11/14 (P = 0.01 versus pre-protocol) with the main indication being a persistent bile leak. Re-laparoscopy was necessary in 5/14 (P = 0.05 versus preprotocol). No laparotomies were performed (P < 0.01 versus pre-protocol) and there were no postoperative deaths. Median hospital stay was 11 days (range, 5-55 days).

CONCLUSIONS

The introduction of a minimally invasive protocol utilising ERC and re-laparoscopy offers an effective modern algorithm for the management of bile leaks after laparoscopic cholecystectomy.

Evidence for non-HFE linked hemochromatosis in Asian Indians

BACKGROUND

Hereditary hemochromatosis is commonly due to two HFE1 (Histone Family E1) gene mutations - H63D and C282Y. Mutations in the Asian Indians are less well studied.

AIMS

The aim of this preliminary study was to find out the prevalence of HFE gene mutations in nonviral liver cirrhosis patients.

SETTINGS AND DESIGN

Unexplained liver cirrhosis cases with transferrin saturation> 45%, attending the gastroenterology clinic in the years 2004 and 2005 were subjects of the prospective study. Asymptomatic individuals with negative family history of hemolytic anemia or liver disease served as controls.

MATERIALS AND METHODS

The clinical presentation was recorded in the patients. Transferrin saturation was estimated by standard colorimetric technique. The two common mutations in HFE1 gene and Y250X mutation of TFR (transferrin receptor) gene were studied by polymerase chain reaction based methods.

RESULTS

A majority of the cases were sporadic, but family history was positive in four patients. In one family with multiple affected members, there was clear evidence of autosomal dominant inheritance. Seven out of 31 (22.6%) of unexplained cirrhosis cases were positive for mutations. One was homozygous for H63D. In healthy controls, prevalence was 8.1% (6/74). None of the patients or controls was positive for C282Y mutation of HFE1 or Y250X of TFR gene.

CONCLUSIONS

Thus, in a number of cases of hemochromatosis in Indians, a gene with dominant inheritance may be involved in causation of the phenotype. The prevalence of HFE mutations in Indians is comparable to that reported from neighboring countries. It is worth studying other mutations in HFE gene and other iron overload genes in cryptogenic cirrhosis cases.

Diminishing of aggregation for bovine liver catalase through acidic residues modification

The tendency of proteins to aggregate is an important problem in biotechnology and the pharmaceutical industry. Because proteins in the aggregated state generally do not have the same biological activity as proteins in the native state. In order to prevent aggregation, it is essential to know the effective parameters in anti-aggregation mechanism. Using a chemical protein modification approach, UV-vis and fluorescence spectroscopies and circular dichroism spectropolarimetry, this study investigates the parameters involved in anti-aggregation mechanism of bovine liver catalase. Our findings clearly indicate that the modified bovine liver catalase provides better protection than the native enzyme against thermal aggregation. It seems that a decrease in hydrophobicity resulting in chemical modification plays an important role in preventing aggregation.

Chemometric studies of lysozyme upon interaction with sodium dodecyl sulfate and β-cyclodextrin

The interaction of hen egg-white lysozyme with sodium n-dodecyl sulfate (SDS) as an anionic surfactant was investigated by UV-vis spectrophotometry at different pHs at 25 degrees C using HCl/glycine and NaOH/glycine for acidic and basic pH ranges, respectively. Analysis of the spectral data using chemometric method gave the evidence for the existence of intermediate components during the cited interaction. Results also indicated a connection between turbidity of the protein solution upon interaction with SDS and distribution of our newly found intermediates. As intermediates are important in aggregation of proteins, beta-cyclodextrin was employed as an anti-aggregation agent and the results obtained for the lysozyme-SDS-beta-cyclodextrin ternary system were compared with those obtained in the absence of beta-cyclodextrin on distribution and mole fraction of intermediates with. It is also shown that as the distribution of intermediates broadens in a range of SDS concentrations, the turbidity and aggregation state of solution are reduced.

Sentinel laboratory surveillance of hepatitis C antibody testing in England: understanding the epidemiology of HCV infection

This paper describes sentinel laboratory surveillance of hepatitis C antibody testing in England. Demographic and test result data were supplemented by follow-up questionnaires sent to the requesting clinician. Between October 2002 and September 2003 almost 75000 anti-HCV tests were performed in eight sentinel centres. More males were tested than females and over half of those tested were aged 25-44 years. Overall 5.7% (3333/58144, range 2.8-7.7%) individuals tested positive. Follow-up questionnaire data showed that 82% (1043/1277) of the positives had injecting drug use reported as the main risk exposure. The majority of negative individuals were undergoing routine screening as recommended for specific patient groups. Most individuals were asymptomatic. Antibody prevalence was estimated to be 34% in current injecting drug users and 42% in former injectors. Comparing positives to routine national surveillance suggests that only 53% (1782/3333) of diagnosed cases were reported. Sentinel laboratory data can provide valuable supplementary data to national surveillance.

Cytogenetic investigation in chronic myeloid leukemia: study from an Indian population

Chronic myeloid leukemia (CML) is a malignant neoplasm of hematopoietic cells characterized by abnormal proliferation of myeloid precursors, decreased rates of self destruction and an arrest in cellular differentiation. The bone marrow and peripheral blood accumulates all forms of mature and immature granulocytes, primarily blast cells. It is the most common type of leukemia seen in India, accounting for 30% of all leukemias. Cytogenetic analysis plays a vital and important role in the diagnosis of CML patients. The present study consists of cytogenetic evaluation of 175 CML cases from the Indian population with ages ranging from 6-86 years (mean of 42.8). The study population included 115 males (65.72%) and 60 females (34.28%) with a Male: Female ratio 1.9:1. Out of the 175 cases, 164 (93.7%) were successfully karyotyped while culture failure was observed for 11 (6.3%). Among the 164 reported cases, 53 (32.3%) showed a normal karyotype while within the 111 (67.7%) abnormal cases, 96 cases (86.5%) showed the presence of Philadelphia (Ph') chromosome with standard translocation t(9;22); Ph'+ve along with secondary aberrations was detected in 9 (8.1%) cases. Variants of Ph' chromosome were detected in only one case (0.9%). Ph'-ve CML with other chromosomal aberrations were detected in 5 (4.5%) cases, including +8, del 20q, del 11q and marker chromosome. Furthermore, we believe that availability of more advanced molecular techniques can be used as a supportive tool in CML diagnosis even though it cannot fully replace cytogenetics, which remains the backbone for laboratory investigation of the disease.

Acute aortic syndrome: pathology and therapeutic strategies

Acute aortic syndrome (AAS) describes the acute presentation of patients with characteristic "aortic pain" caused by one of several life threatening thoracic aortic pathologies. These include aortic dissection, intramural haematoma, penetrating atherosclerotic ulcer, aneurysmal leak, and traumatic transection. AAS heralds imminent aortic rupture. Highlighting acute aortic pathology as an AAS is therefore important to encourage prompt recognition of this condition and avoid diagnostic delays. The management of AAS remains a therapeutic challenge. The traditional surgical approach to acute "type B" (descending thoracic) aortic pathology is unsatisfactory with high morbidity and mortality. Endovascular aortic stent grafts now represent an alternative minimally invasive approach in these patients who are often poor surgical candidates. Studies show endovascular repair to be technically feasible with fewer complications. This review discusses AAS pathology and in particular assesses the current role for endovascular aortic repair in its treatment.

The Correlation of RNase A Enzymatic Activity with the Changes in the Distance between Nε2-His12 and Nδ1-His119 Upon Addition of Stabilizing and Destabilizing Salts

The effect of stabilizing and destabilizing salts on the catalytic behavior of ribonuclease A (RNase A) was investigated at pH 7.5 and 25 degrees C, using spectrophotometric, viscometric and molecular dynamic methods. The changes in the distance between N(epsilon2) of His(12) and N(delta1) of His(119) at the catalytic center of RNase A upon the addition of sodium sulfate, sodium hydrogen sulfate and sodium thiocyanate were evaluated by molecular dynamic methods. The compactness and expansion in terms of Stokes radius of RNase A upon the addition of sulfate ions as kosmotropic salts, and thiocyanate ion as a chaotropic salt, were estimated by viscometric measurements. Enzyme activity was measured using cytidine 2', 3'-cyclic monophosphate as a substrate. The results from the measurements of distances between N(epsilon2) of His(12) and N(delta1) of His(119) and Stokes radius suggest (i) that the presence of sulfate ions decreases the distance between the catalytic His residues and increases the globular compactness, and (ii) that there is an expansion of the enzyme surface as well as elongation of the catalytic center in the presence of thiocyanate ion. These findings are in agreement with activity measurements.

Comparative Study of the Conformational Lock, Dissociative Thermal Inactivation and Stability of Euphorbia Latex and Lentil Seedling Amine Oxidases

The thermal stability of copper/quinone containing amine oxidases from Euphorbia characias latex (ELAO) and lentil seedlings (LSAO) was measured in 100 mM potassium phosphate buffer (pH 7.0) following changes in absorbance at 292 nm. ELAO was shown to be about 10 degrees C more stable than LSAO. The dissociative thermal inactivation of ELAO was studied using putrescine as substrate at different temperatures in the range 47-70 degrees C, and a "conformational lock" was developed using the theory pertaining to oligomeric enzyme. Moreover ELAO was shown to be more stable towards denaturants than LSAO, as confirmed by dodecyl trimethylammonium bromide denaturation curves. A comparison of the numbers of contact sites in inter-subunits of ELAO relative to LSAO led us to conclude that the higher stability of ELAO to temperature and towards denaturants was due to the presence of larger number of contact sites in the conformational lock of the enzyme. This study also gives a putative common mechanism for thermal inactivation of amine oxidases and explains the importance of C-terminal conserved amino acids residues in this class of enzymes.

Experience with video-assisted surgery for suspected mediastinal tumours

AIM

To assess the therapeutic feasibility of video-assisted thoracoscopic surgery (VATS) in the excision of suspected mediastinal tumours.

METHODS

The case notes of 24 consecutive patients referred to a single surgeon between 1997 and 2002 for excision of suspected mediastinal tumours were reviewed. The operative, post-operative and pathological characteristics of patients treated thoracoscopically and by open procedure were analysed.

RESULTS

Thirteen of 24 patients underwent thoracoscopic excision. The mean age of the two groups was similar as was the mean operating time and duration of chest drainage. However, patients in the thoracoscopic group had less chest drainage, less pain and a shorter hospital stay.

CONCLUSIONS

Video-assisted thoracoscopic excision of mediastinal tumours is a safe and technically feasible procedure and may offer significant post-operative advantages over open procedures.

Pregnancy after breast cancer

The issue of pregnancy in patients previously treated for breast cancer is controversial. This paper reviews the literature using Medline and Embase databases over the last 50 years to address the issue. Overall survival in patients treated for breast cancer who subsequently become pregnant compares favourably with controls. This paper also addresses the effects of adjuvant therapy (loco-regional and systemic) on subsequent pregnancy. Introduction of a national registry of these patients may help inform such patients in the future.

Physician health, stress and gender at a university hospital

OBJECTIVE

To determine personal and work related factors contributing to physician health and stress in men and women physicians in a university hospital.

METHOD

Mail survey of 161 hospital-based Canadian academic physicians (51 women, 110 men).

RESULTS

Women compared to men, physicians were younger (M = 43 years, S.D. = 7.4 vs. M = 48 years, S.D. = 8.64; P = .001) and fewer had spouses (76% vs. 90%; P = .01) and children (76% vs. 91%; P = .02). A five-item scale measured somatic symptoms, the dependent variable. Among physicians of both gender, the somatic symptoms scale was significantly correlated with satisfaction with amount of time spent working and scales of mental health (five items), work satisfaction (five items), workload (five items), healthy lifestyle (five items), coping abilities (three items) and support-in-stress (two items). On stepwise regression analysis, for women physicians, 70% of the variance in somatic symptoms was explained by support from colleagues when stressed, and workload. For men, 42% of the variance was explained by healthy lifestyle, mental health, support from colleagues when stressed, and workload. Regardless of gender, the majority of physicians reported an excessive workload but the sources of support when stressed varied by gender.

CONCLUSION

Different strategies are needed for women and men physicians to reduce their stress levels.

Molecular cytogenetic discrimination and reaction to wheat streak mosaic virus and the wheat curl mite in Zhong series of wheat--Thinopyrum intermedium partial amphiploids

Thinopyrum intermedium (2n = 6x = 42, JJJsJsSS) is potentially a useful source of resistance to wheat streak mosaic virus (WSMV) and its vector, the wheat curl mite (WCM). Five partial amphiploids, namely Zhong 1, Zhong 2, Zhong 3, Zhong 4, and Zhong 5, derived from Triticum aestivum x Thinopyrum intermedium crosses produced in China, were screened for WSMV and WCM resistance. Zhong 1 and Zhong 2 had high levels of resistance to WSMV and WCM. The other three partial amphiploids, Zhong 3, 4, and 5, were resistant to WSMV, but were susceptible to WCM. Genomic in situ hybridization (GISH) using a genomic DNA probe from Pseudoroegneria strigosa (SS, 2n = 14) demonstrated that two partial amphiploids, Zhong 1 and Zhong 2, have almost the identical 10 Th. intermedium chromosomes, including four Js, four J, and two S genome chromosomes. Both of them carry two pairs of J and a pair of Js genome chromosomes and two different translocations that were not observed in the other three Zhong lines. The partial amphiploids Zhong 3, 4, and 5 have another type of basic genomic composition, which is similar to a reconstituted alien genome consisting of four S and four Js genome chromosomes of Th. intermedium (Zhong 5 has two Js chromosomes plus two Js-W translocations) with six translocated chromosomes between S and Js or J genomes. All three lines carry a specific S-S-Js translocated chromosome, which might confer resistance to barley yellow dwarf virus (BYDV-PAV). The present study identified a specific Js2 chromosome present in all five of the Zhong lines, confirming that a Js chromosome carries WSMV resistance. Resistance to WCM may be linked with J or Js chromosomes. The discovery of high levels of resistance to both WSMV and WCM in Zhong 1 and Zhong 2 offers a useful source of resistance to both the virus and its vector for wheat breeding programs.