TKS5-positive invadopodia-like structures in human tumor surgical specimens

Invadopodia, cancer cell protrusions with proteolytic activity, are functionally associated with active remodeling of the extracellular matrix. Here, we show that the invadopodia-related protein TKS5 is expressed in human pancreatic adenocarcinoma lines, and demonstrate that pancreatic cancer cells depend on TKS5 for invadopodia formation and function. Immunofluorescence staining of human pancreatic cancer cells reveals that TKS5 is a marker of mature and immature invadopodia. We also analyze the co-staining patterns of TKS5 and the commonly used invadopodia marker Cortactin, and find only partial co-localization of these two proteins at invadopodia, with a large fraction of TKS5-positive invadopodia lacking detectable levels of Cortactin. Whereas compelling evidence exist on the role of invadopodia as mediators of invasive migration in cultured cells and in animal models of cancer, these structures have never been detected inside human tumors. Here, using antibodies against TKS5 and Cortactin, we describe for the first time structures strongly resembling invadopodia in various paraffin-embedded human tumor surgical specimens from pancreas and other organs. Our results strongly suggest that invadopodia are present inside human tumors, and warrants further investigation on their regulation and occurrence in surgical specimens, and on the value of TKS5 antibodies as pathological research and diagnostic tools.

Elevated Aminotransferases are Predictors of Hepatic Injury in Blunt Abdominal Trauma Patients

Objective

Computed tomography (CT) scan is currently the most commonly used tool for evaluating solid-organ injuries in trauma management. However, liberal use of CT scanning increases the risk of excess radiation exposure and toxicity from contrast material. Animal studies and clinical research on the paediatric population indicated that liver enzymes elevations were related to hepatic injury. The present study was undertaken to determine whether elevated liver enzymes were associated with the occurrence of hepatic injury in adult patients with blunt abdominal trauma.

Methods

This is a cross-sectional study from August 2003 to October 2006. All adult patients with blunt injury to abdomino-pelvic organs documented by CT or surgery who were admitted to Chi-Mei Medical Centre in the captioned period were included. The study population sorted to hepatic injury (HI) and no hepatic injury (NHI) groups according to the presence or absence of hepatic injury. Variables including liver enzymes were compared between the groups.

Results

Totally 419 patients were included, including 150 patients in the HI group and 269 patients in the NHI group. The HI group was younger and had a lower rate of laparotomy (36.3 years old vs 41.4 years old; 26% vs 42%, respectively). The mean levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the HI group were significantly higher than levels in the NHI group (439.6 IU/L vs 104.7 IU/L; 353.5 IU/L vs 76.6 IU/L, p<0.01). We define AST >200 IU/L or ALT level >125 IU/L as abnormal according to previous studies. The diagnostic characteristics of hepatic injury were 87.3% sensitivity, 80.3% specificity, 71.2% positive predictive value, and 91.9% negative predictive value.

Conclusion

In adults who have experienced blunt abdominal trauma, AST >200 U/L or of ALT >125 U/L are practical predictors of hepatic injury. Screening serum aminotransferases will have a role in detecting occult hepatic injury and may reduce the hazards of excessive CT scanning. (Hong Kong j.emerg.med. 2013;20:337-342)

Severe Hyperemesis Gravidarum Masking the Presentations of Hyperthyroidism

Hyperemesis gravidarum may present with weight loss and tachycardia secondary to dehydration. Its severity correlates with the level of the serum chorionic gonadotropin which can interfere with the assay of the thyroid stimulating hormone. Therefore, hyperemesis gravidarum are at times difficult to be distinguished from hyperthyroidism. Missing hyperthyroidism during pregnancy results not only in inappropriate maternal care, but adverse neonatal outcomes including low birth weight. The authors report a case of hyperemesis gravidarum complicated by the concurrence of hyperthyroidism. Goiter and refractory tachycardia are the useful clues to detect occult hyperthyroidism in patients with hyperemesis gravidarum.

Morbidity among long-term survivors after pancreatoduodenectomy for pancreatic adenocarcinoma

BACKGROUND

Because pancreatoduodenectomy for pancreatic adenocarcinoma is focused on disease-free and overall survival, morbidity among long-term survivors is not well described. This study sought to evaluate outcomes for long-term survivors of pancreatic cancer after pancreatoduodenectomy.

METHODS

The authors identified 29 patients from their prospectively collected database of patients with pancreatic adenocarcinoma who had undergone pancreatoduodenectomy and were without evidence of disease during at least 3 years of follow-up evaluation. Demographics, treatment, and pathologic characteristics were collected for review. Data with regard to long-term sequelae also were collected, focusing on those complications requiring additional procedures and on the development of metachronous cancers.

RESULTS

The median follow-up period was 83 months, with 62 % of patients still alive. All patients received an R0 resection, and 34 % of the patients had N1 disease. For 42 % of the patients, no significant subsequent sequelae occurred. In the four remaining patients (14 %), ascites developed, requiring repeated paracentesis or Denver shunt, with a median time to development (MTD) of 63 months. Six patients (21 %) experienced a biliary stricture requiring stent placement (MTD, 56 months). One patient experienced portal venous thrombosis requiring a venous stent (MTD, 52 months), and four patients (14 %) experienced clinically significant ulcers (MTD, 52 months). With regard to metachronous cancers, two patients experienced subsequent lymphomas (MTD, 92 months).

CONCLUSIONS

Long-term survivors among patients who undergo pancreatoduodenectomy for pancreatic adenocarcinoma can experience significant late sequelae, which often manifest more than 3 years after surgery. As such, continued follow-up evaluation and counseling are warranted.

Neoadjuvant chemoradiation and duration of chemotherapy before surgical resection for pancreatic cancer: does time interval between radiotherapy and surgery matter?

BACKGROUND

Neoadjuvant chemoradiation and chemotherapy provided for borderline or locally advanced, potentially resectable pancreatic adenocarcinoma improves resectability rates. Response to therapy is also an important prognostic factor. There are no data in the literature regarding optimal time interval or duration of chemotherapy after chemoradiation before surgery, and pathologic response rates. Using our database, we evaluated these relationships and the effect on overall and progression-free survival.

METHODS

We retrospectively analyzed the records of 83 patients who underwent neoadjuvant chemoradiation for locally advanced, potentially resectable, and borderline resectable pancreatic cancers before definitive resection. We divided patients into three groups according to time interval between completion of chemoradiation and resection: group A (0-10 weeks), group B (11-20 weeks), and group C (>20 weeks). After chemoradiation, patients underwent ongoing chemotherapy before resection. Pathologic response was defined as major (>95% fibrosis), partial (50-94% fibrosis), or minor (<50% fibrosis).

RESULTS

There were 56 patients in group A, 17 patients in group B, and 10 patients in group C. Patients in groups B and C were significantly more likely to experience a major response than group A (p < 0.013). Patients in group C had significantly increased median progression-free and overall survival (p < 0.05). Multivariable classification and regression tree analysis demonstrated pathologic response to be the only significant factor in overall survival.

CONCLUSIONS

Patients who underwent a prolonged time interval after neoadjuvant chemoradiation with ongoing chemotherapy were more likely to have an improved pathologic response at time of surgical resection, which was associated with improved median overall survival.

Factors affecting the use of anti-amoebiasis protective measures among Taiwan immigrants returning to amoebiasis-endemic regions

OBJECTIVE

To investigate the predictors of use of anti-amoebiasis protective measures (AAPMs) among Taiwan immigrants returning to their country of origin, using the Health Belief Model (HBM) to guide the investigation.

DESIGN

Cross-sectional study.

METHODS

Between March and May 2011, all permanent immigrants originating from amoebiasis-endemic countries who received services at the immigrant service centres in Taipei or Tainan and who reported that they had returned to their country of origin within the past five years were enrolled in the study. A structured questionnaire containing questions on sociodemographic characteristics and items related to the constructs of the HBM was used as the data collection instrument.

RESULTS

Complete information was collected from 384 immigrants, with a response rate of 80% (384/480). The mean age of the subjects was 38.4 years (standard deviation 10.6 years). The majority (70%) of participants did not receive travel information through a pretravel consultation, and more than 17% reported that they did not use measures to prevent amoebiasis. Multiple regression analyses revealed that Chinese proficiency, pretravel consultation and lower barriers to using protective measures were significantly associated with the use of AAPMs during return trips to country of origin (R(2) = 0.45; F = 77.5; P < 0.001).

CONCLUSION

The HBM significantly predicted the use of AAPMs in this study. A high proportion of immigrants did not use appropriate AAPMs when they returned to their country of origin. Educational approaches should be targeted at immigrants originating from amoebiasis-endemic regions who return to their country of origin.

A better prognosis for Merkel cell carcinoma of unknown primary origin

BACKGROUND

There is limited evidence that Merkel cell carcinoma (MCC) arising from a nodal basin without evidence of a primary cutaneous (PC) site has better prognosis. We present our experience at 2 tertiary care referral centers with stage III MCC with and without a PC site.

METHODS

Fifty stage III MCC patients were identified between 1996 and 2011. Clinical data were analyzed, with primary endpoints being disease-free survival and overall survival.

RESULTS

Of stage III patients, 34 patients presented with a PC site and 16 patients with an unknown primary (UP) site. Treatment strategies varied; of patients with UP vs. PC sites, 25% vs. 44% underwent combined regional lymphadenectomy and radiation, with an additional 25% vs. 15% receiving chemotherapy. The median disease-free survival for a UP site was not reached vs. 15 months for a PC site (hazards ratio = .48, P = .18). The median overall survival for a UP site was not reached vs 21 months for a PC site (hazards ratio = .34, P = .03). Multivariate analysis showed that UP status was a significant factor in overall survival (P = .002).

CONCLUSIONS

Stage III MCC with a UP site portends a better prognosis than MCC with a PC site.

Conjunctival Inclusion Cyst

Conjunctival inclusion cysts are the most common cystic lesions of the conjunctiva and are either congenital or acquired; the latter are more prevalent. Some of the major factors that provoke the development of an acquired cyst are surgery, trauma, and chronic inflammation. Here, we report on a conjunctival inclusion cyst that developed following a case of untreated chronic conjunctivitis. To temporarily relieve the patient's symptoms a needle aspiration of the cyst was performed, and the patient was referred to an ophthalmologist for surgical excision of the cyst.

Cerebral “eThrombosis”: Cerebral Venous Sinus Thrombosis Associated with Prolonged Sitting in Front of a Computer

Venous thromboembolism caused by prolonged sitting during air travel has been recognised as economy-class syndrome for more than 30 years. Since 2003, the term “eThrombosis” has been proposed to describe the 21st Century variant of venous thromboembolism associated with immobilisation. We reported a case of cerebral venous sinus thrombosis presenting with severe headache after a prolonged period of sitting for over 12 hours in front of a computer for recreational purpose. We described this case as cerebral “eThrombosis”. Considering the widespread use of computers for many purposes including working, recreation and communications in the present digital era, we would like to put forward that prolonged immobilisation associated with computer use is a possible provoking risk factor of cerebral venous sinus thrombosis.

Severe Hyperemesis Gravidarum Masking the Presentations of Hyperthyroidism

Hyperemesis gravidarum may present with weight loss and tachycardia secondary to dehydration. Its severity correlates with the level of the serum chorionic gonadotropin which can interfere with the assay of the thyroid stimulating hormone. Therefore, hyperemesis gravidarum are at times difficult to be distinguished from hyperthyroidism. Missing hyperthyroidism during pregnancy results not only in inappropriate maternal care, but adverse neonatal outcomes including low birth weight. The authors report a case of hyperemesis gravidarum complicated by the concurrence of hyperthyroidism. Goiter and refractory tachycardia are the useful clues to detect occult hyperthyroidism in patients with hyperemesis gravidarum.

Capnography: An Accurate Method to Assess the Position of the Feeding Tube in a Porcine Model

Objective

To test the accuracy of capnography in the differential placement of feeding tubes into the trachea versus the oesophagus.

Method

Nineteen pigs were anesthetised, and feeding tubes were placed into their tracheas and oesophagi. A naïve examiner attached a capnography to the tube and evaluated the presence or absence of flow waveforms on the capnography. In the next step experiment, we gave 20 intentional oesophageal ventilations to the animals to create a distended stomach. The feeding tubes were reinserted, and examined by a naïve examiner by capnography.

Results

Capnography demonstrated continuous flow waveforms for the feeding tubes placed in the tracheas, but no waveforms were observed for those placed in the oesophagi. In the next step experiment, we found the same results.

Conclusion

Capnography can be used to accurately determine the placement of tracheal versus oesophageal feeding tubes based on the presence or absence of flow waveforms.

Donor transmission of melanoma following renal transplant

Donor transmission of melanoma is one of the more common and lethal of recipient malignancies, often presenting with systemic disease. Although some patients may receive durable remission of melanoma following explantation of the allograft and withdrawal of immunosuppression, donor transmission of melanoma is fatal in most patients. Here we present a case of a 44-year-old male who developed metastatic melanoma following renal transplant.

Clostridium difficile infection in the pediatric surgery population

PURPOSE

The incidence of Clostridium difficile-associated disease (CDAD) in the adult population doubled in the past decade, with increasing morbidity and mortality; however, little research has been performed in the pediatric population. We characterized C difficile infection in the pediatric population, with emphasis on the surgical population.

METHODS

At a university-based children's hospital, we reviewed 231 patient (birth to 18 years of age) records containing a diagnosis of CDAD between January 1, 2002, and December 31, 2008.

RESULTS

Clostridium difficile-associated disease incidence increased from 250 per 100,000 hospitalizations in 2002 to 580 per 100,000 hospitalizations in 2008. No fatalities or surgical interventions were attributable to CDAD. Eighty-seven percent of patients received antibiotics within 2 months of diagnosis. Fifty-two percent of patients underwent operative intervention within 2 months of diagnosis; of these, 89% percent received previous antibiotic therapy and 57% were immunosuppressed. The most common antecedent procedures were bone marrow biopsy and line placement for myelodysplastic diseases (40%), followed by renal transplant (11%).

CONCLUSIONS

Pediatric CDAD incidence doubled during the study period but was not associated with death or operative intervention. A substantial number of CDAD cases were associated with previous operative procedures, particularly in immunosuppressed patients and those who received prior antibiotics.

Margin status and neoadjuvant chemoradiation in patients with borderline resectable pancreatic cancer

304

Background: The objective of this study was to examine the effect of margin status and neoadjuvant therapy in determining outcomes for borderline resectable (BLR) pancreatic cancer and how neoadjuvant chemoradiation impacts margin of resection.

Methods: A retrospective chart review was conducted to identify patients who underwent resection for BLR pancreatic cancer based on the AHPBA/SSO/SSAT consensus definition. Outcomes including overall survival (OS) and disease free survival (DFS) were determined based on margin status, location of positive margin (artery, vein, or pancreas), and receipt of neoadjuvant chemoradiation.

Results: One hundred and three patients who met the definition of BLR pancreatic cancer and underwent resection between April 1993 and July 2010 were reviewed. Mean age at diagnosis was 65 with a median follow up time of 19.7 months. Neoadjuvant chemoradiation was administered in 49.5% of patients. Twenty-five percent of patients underwent portal and/or superior mesenteric vein resection, and 7% hepatic artery resection. Microscopic positive margin rate was 54%. Median OS was 17.2 months for patients with positive margins versus 24.9 months for patients with negative margins (p=0.003). Median DFS was 13.1 months for patients with positive margins versus 18.6 months for patients with negative margins (p=0.001). There was no difference in OS or DFS for patients with positive margins based on location or number of positive margins. Of the patients who received neoadjuvant chemoradiation, 61.7% had a negative margin of resection versus a 38.3% negative margin of resection rate for patients who did not receive neoadjuvant chemoradiation (p=0.02). Among patients with a positive margin, there was no difference in OS or DFS with or without neoadjuvant chemoradiation.

Conclusions: A positive margin of resection, irrespective of location or number, is associated with worse outcome in patients with BLR pancreatic cancer. The use of neoadjuvant chemoradiation is associated with higher rates of margin free resection.

Revisiting the prognostic significance of positive peritoneal cytology in pancreatic cancer

177

Background: Positive peritoneal cytology (PPC) in the setting of pancreatic cancer predicts a poor prognosis, such that it is considered metastatic disease in the American Joint Commission on Cancer staging guidelines. We re-evaluate the role of PPC, with particular attention to outcomes following neoadjuvant therapy.

Methods: We retrospectively identified 185 patients from January 1, 2000 to present with the diagnosis of pancreatic adenocarcinoma who had undergone peritoneal washings with cytology at the time of planned resection. Data regarding demographics, tumor stage, intraoperative cytology, surgical and chemoradiation therapeutics, and clinicopathological outcomes were analyzed, with the primary endpoints being disease-free and overall survival (DFS and OS).

Results: 20 patients (11%) had PPC at the time of planned resection; of these, 11 patients (55%) received neoadjuvant therapy prior to surgery. 165 patients (89%) had negative peritoneal cytology (NPC) at the time of planned resection; of these, 75 (45%) received neoadjuvant therapy prior to surgery. All patients proceeded with resection in the absence of visible metastatic disease. 42% of NPC reached 2-year survival compared to just 20% of patients with PPC. Overall, patients with PPC vs. NPC had significantly poorer DFS (p<0.0064) and OS (p<0.0135). When stratifying by neoadjuvant therapy, in those patients with stage II disease or higher who did not receive neoadjuvant therapy, multivariable CART analysis revealed that PPC predicted poorer DFS compared with NPC (p<0.004). However, among stage II or higher disease receiving neoadjuvant therapy, it failed to show a significant difference in DFS or OS between PPC and NPC.

Conclusions: Overall, patients with positive peritoneal cytology are shown to have worse DFS and OS compared to patients with negative peritoneal cytology in pancreatic adenocarcinoma. However, after multivariable analysis, the prognostic significance of positive peritoneal cytology disappears in those patients with stage II and higher disease receiving neoadjuvant therapy.

A role for intestinal alkaline phosphatase in the maintenance of local gut immunity

BACKGROUND AND AIMS

Intestinal alkaline phosphatase (IAP) is a gut mucosal defense factor known to dephosphorylate lipopolysaccharide (LPS); however, the role of IAP in the gut response to luminal bacteria remains poorly defined. We investigated immune responses of wild-type (WT) and IAP-knockout (IAP-KO) mice to LPS and Salmonella typhimurium challenges.

METHODS

Cryostat sectioning and standard indirect immunohistochemical staining for major histocompatibility complex (MHC) class II molecules were performed on liver tissue from WT and IAP-KO mice. WT and IAP-KO mice were orally gavaged with S. typhimurium; bacterial translocation to mesenteric nodes, liver, and spleen was determined by tissue homogenization and plating. In other experiments, WT and IAP-KO mice received intraperitoneal injections of LPS, with subsequent quantification of complete blood counts and serum interleukin (IL)-6 by enzyme-linked immunosorbent assay (ELISA). WT and IAP-KO whole blood were plated and stimulated with LPS and Pam-3-Cys, followed by cytokine assays.

RESULTS

Immunohistologic liver examinations showed increased expression of MHC class II molecules in IAP-KO mice. Following S. typhimurium challenge, WT mice appeared moribund compared with IAP-KO mice, with increased bacterial translocation. WT mice had >50% decrease (P<.005) in platelets and 1.8-fold (P<.05) increased serum IL-6 compared with IAP-KO mice in response to LPS injections. IAP-KO whole-blood stimulation with LPS and Pam-3-Cys resulted in increased IL-6 and tumor necrosis factor (TNF)-alpha secretion compared with WT.

CONCLUSIONS

IAP-KO mice exhibit characteristics consistent with local LPS tolerance. Whole-blood response of IAP-KO mice did not reflect systemic tolerance. These data suggest that IAP is a local immunomodulating factor, perhaps regulating LPS-toll-like receptor 4 (TLR4) interaction between commensal microflora and intestinal epithelium.

Intestinal alkaline phosphatase has beneficial effects in mouse models of chronic colitis

BACKGROUND

The brush border enzyme intestinal alkaline phosphatase (IAP) functions as a gut mucosal defense factor and is protective against dextran sulfate sodium (DSS)-induced acute injury in rats. The present study evaluated the potential therapeutic role for orally administered calf IAP (cIAP) in two independent mouse models of chronic colitis: 1) DSS-induced chronic colitis, and 2) chronic spontaneous colitis in Wiskott-Aldrich Syndrome protein (WASP)-deficient (knockout) mice that is accelerated by irradiation.

METHODS

The wildtype (WT) and IAP knockout (IAP-KO) mice received four cycles of 2% DSS ad libitum for 7 days. Each cycle was followed by a 7-day DSS-free interval during which mice received either cIAP or vehicle in the drinking water. The WASP-KO mice received either vehicle or cIAP for 6 weeks beginning on the day of irradiation.

RESULTS

Microscopic colitis scores of DSS-treated IAP-KO mice were higher than DSS-treated WT mice (52±3.8 versus 28.8±6.6, respectively, P<0.0001). cIAP treatment attenuated the disease in both groups (KO=30.7±6.01, WT=18.7±5.0, P<0.05). In irradiated WASP-KO mice cIAP also attenuated colitis compared to control groups (3.3±0.52 versus 6.2±0.34, respectively, P<0.001). Tissue myeloperoxidase activity and proinflammatory cytokines were significantly decreased by cIAP treatment.

CONCLUSIONS

Endogenous IAP appears to play a role in protecting the host against chronic colitis. Orally administered cIAP exerts a protective effect in two independent mouse models of chronic colitis and may represent a novel therapy for human IBD.

Intestinal alkaline phosphatase preserves the normal homeostasis of gut microbiota

BACKGROUND AND AIMS

The intestinal microbiota plays a critical role in maintaining human health; however, the mechanisms governing the normal homeostatic number and composition of these microbes are largely unknown. Previously it was shown that intestinal alkaline phosphatase (IAP), a small intestinal brush border enzyme, functions as a gut mucosal defence factor limiting the translocation of gut bacteria to mesenteric lymph nodes. In this study the role of IAP in the preservation of the normal homeostasis of the gut microbiota was investigated.

METHODS

Bacterial culture was performed in aerobic and anaerobic conditions to quantify the number of bacteria in the stools of wild-type (WT) and IAP knockout (IAP-KO) C57BL/6 mice. Terminal restriction fragment length polymorphism, phylogenetic analyses and quantitative real-time PCR of subphylum-specific bacterial 16S rRNA genes were used to determine the compositional profiles of microbiotas. Oral supplementation of calf IAP (cIAP) was used to determine its effects on the recovery of commensal gut microbiota after antibiotic treatment and also on the colonisation of pathogenic bacteria.

RESULTS

IAP-KO mice had dramatically fewer and also different types of aerobic and anaerobic microbes in their stools compared with WT mice. Oral supplementation of IAP favoured the growth of commensal bacteria, enhanced restoration of gut microbiota lost due to antibiotic treatment and inhibited the growth of a pathogenic bacterium (Salmonella typhimurium).

CONCLUSIONS

IAP is involved in the maintenance of normal gut microbial homeostasis and may have therapeutic potential against dysbiosis and pathogenic infections.

Identification of specific targets for the gut mucosal defense factor intestinal alkaline phosphatase

Intestinal alkaline phosphatase (IAP) is a small intestinal brush border enzyme that has been shown to function as a gut mucosal defense factor, but its precise mechanism of action remains unclear. We investigated the effects of IAP on specific bacteria and bacterial components to determine its molecular targets. Purulent fluid from a cecal ligation and puncture model, specific live and heat-killed bacteria (Escherichia coli, Salmonella typhimurium, and Listeria monocytogenes), and a variety of proinflammatory ligands (LPS, CpG DNA, Pam-3-Cys, flagellin, and TNF) were incubated with or without calf IAP (cIAP). Phosphate release was determined by using a malachite green assay. The various fluids were applied to target cells (THP-1, parent HT-29, and IAP-expressing HT-29 cells) and IL-8 secretion measured by ELISA. cIAP inhibited IL-8 induction by purulent fluid in THP-1 cells by >35% (P < 0.005). HT29-IAP cells had a reduced IL-8 response specifically to gram-negative bacteria; >90% reduction compared with parent cells (P < 0.005). cIAP had no effect on live bacteria but attenuated IL-8 induction by heat-killed bacteria by >40% (P < 0.005). cIAP exposure to LPS and CpG DNA caused phosphate release and reduced IL-8 in cell culture by >50% (P < 0.005). Flagellin exposure to cIAP also resulted in reduced IL-8 secretion by >40% (P < 0.005). In contrast, cIAP had no effect on TNF or Pam-3-Cys. The mechanism of IAP action appears to be through dephosphorylation of specific bacterial components, including LPS, CpG DNA, and flagellin, and not on live bacteria themselves. IAP likely targets these bacterially derived molecules in its role as a gut mucosal defense factor.

Comparison of photodegradative efficiencies and mechanisms of Victoria Blue R assisted by Nafion-coated and fluorinated TiO2 photocatalysts

The purposes of this research were to study the effects of two modified photocatalysts, Nafion-coated TiO(2) and fluorinated TiO(2), and photocatalytic degradation of Victoria Blue R in aqueous solution. Photocatalytic degradation of Victoria Blue R was accelerated by the modified photocatalysts. Bulk and surface characterizations of the resulting powders were carried out. Attachment of the anions to the TiO(2) surface using the Nafion-coated-TiO(2) possibly results in increased adsorption of the cationic dye, and the degradation rate is larger for the cationic dye. It was found that Victoria Blue R on the two illuminated TiO(2) surfaces underwent very different changes. To obtain a better understanding on the mechanistic details of this modified-TiO(2)-assisted photodegradation of the Victoria Blue R dye with UV irradiation, a large number of intermediates of the process were separated, identified, and characterized by a high-performance liquid chromatography-mass spectrometry technique. Several probable photodegradation pathways were proposed and discussed.

Impact of GB virus type C infection on mother-to-child HIV transmission in the Women and Infants Transmission Study Cohort

BACKGROUND

GB virus type C (GBV-C) viraemia is associated with a beneficial outcome in HIV-infected individuals in several though not all studies. GBV-C viraemia was examined in a matched case-control study of 133 HIV-infected pregnant women who transmitted HIV to their infants ('cases') and 266 non-transmitting controls.

METHODS

HIV-infected children and controls were pair-matched for high-risk delivery, race and year of delivery. GBV-C status was determined in maternal plasma samples obtained at or within 3 months of delivery.

RESULTS

Pregnant women with GBV-C viraemia (11% of those studied) had lower HIV RNA levels (P=0.01) and higher CD4 percentages (P=0.0006) [corrected] than women without GBV-C. A trend towards decreased mother-to-child transmission in the multivariate analysis was observed among GBV-C viraemic women delivering after highly active antiretroviral therapy (HAART) became available [odds ratio (OR) 0.30, 95% confidence interval (CI) 0.08-1.05; P=0.06], but not in women delivering prior to the widespread use of HAART.

CONCLUSIONS

GBV-C viraemia was associated with a beneficial effect on CD4 percentage and HIV RNA level in these pregnant women, and was also associated with a trend towards reduced risk of mother-to-child HIV transmission among women after HAART became available. Further studies with larger or multiple cohorts are necessary to assess possible benefits in this population.

Detection of oesophageal intubations using cuff pressures in a pig trachea–oesophagus model

BACKGROUND

The cuff pressures may be different in oesophageal and tracheal intubations. We conducted a study to evaluate if cuff pressures of endotracheal tubes (ETTs) could provide information to distinguish tracheal or oesophageal intubations in a pig trachea-oesophagus model.

METHODS

In each preparation of pig trachea-oesophagus model, the trachea and the oesophagus were intubated separately with a cuffed ETT, and the cuff pressures were measured after each 1 ml increment of air (1-10 ml) during inflation. The cuff pressures and the pressure-volume relationships in both intubations were compared.

RESULTS

The cuff pressures of oesophageal intubations were significantly higher than those of tracheal intubations in all comparisons from 1 to 10 ml of cuff volumes (P < 0.05). The cuff pressure-volume curve was steeper in the oesophageal intubation group, and the difference between the two curves was the largest when the cuff volume was 4-5 ml.

CONCLUSIONS

We conclude that the cuff pressures may be useful in detecting oesophageal intubations. This method is faster than other confirmation measures as it can detect inadvertent oesophageal intubations at the time of inflating the cuffs.