The αvβ6 integrin plays a role in compromised epidermal wound healing

The alphavbeta6 integrin is an exclusively epithelial integrin that is highly expressed during fetal development. In adult tissue, alphavbeta6 integrin is expressed during inflammation, carcinogenesis, and in wound healing. We previously reported that alphavbeta6 integrin is highly expressed in poorly healing human wounds and its over-expression is associated with chronic wounds in a mouse model. The objective of this study was to investigate the role of alphavbeta6 integrin in compromised wound healing induced by hydrocortisone treatment or aging by using young and old mice deficient in or overexpressing the beta6 integrin subunit in the epidermis. Untreated aged beta6 integrin-deficient (beta6-/-) animals showed a significant delay in wound healing when compared to their age-matched controls or younger beta6-/- mice. The most significant delay was observed at the stages where granulation tissue deposition was occurring. Hydrocortisone treatment significantly delayed wound healing in wild-type and beta6 integrin-deficient mice in comparison with the untreated controls. However, hydrocortisone treatment in beta6 integrin overexpressing animals did not cause a significant delay in wound healing. The results of this study suggest that alphavbeta6 integrin plays an important role in wound healing in animals compromised by either age or stress mimicked by hydrocortisone.     

Most human isolates of Mycobacterium avium Mav-A and Mav-B are strong producers of hemolysin, a putative virulence factor

Hemolysin was quantified in 58 isolates of Mycobacterium avium from human, animal, and environmental sources. Human Mav-A and Mav-B isolates were the strongest producers; in contrast, animal and environmental Mav-A isolates and human, animal, and environmental Mav-C organisms were low-level producers. Hemolysin production was not restricted to isolates causing invasive infections.     

Impact of hemochromatosis screening in patients with indeterminate results: the hemochromatosis and iron overload screening study.

PURPOSE: Assess the quality of life impact of receiving indeterminate test results for hemochromatosis, a disorder involving HFE genetic mutations and/or elevated serum transferrin saturation and ferritin. METHODS: The study sample was from the Hemochromatosis and Iron Overload Screening Study, a large observational study of hemochromatosis among primary care patients in the US and Canada using HFE genotype and serum transferrin saturation and ferritin screening. Study subjects included 2,304 patients found with hemochromatosis risk of uncertain clinical significance. Assessed was SF-36 general health and emotional well-being before screening and six weeks after participants received their test results. Health worries were assessed after screening. RESULTS: Of the study subjects, 1,268 participants (51.5%) completed both assessments. Compared to normal controls, those with HFE mutations or elevated serum transferrin saturation and ferritin levels of uncertain significance were more likely to report diminished general health and mental well-being, and more health worries. These effects were associated with participants' belief of having tested positive for hemochromatosis or iron overload. CONCLUSION: Notification of indeterminate results from screening may be associated with mild negative effects on well-being, and might be a potential participant risk in screening programs for disorders with uncertain genotype-phenotype.     

Pseudomonas aeruginosa septicaemia in burns

Out of 1415 patients treated as inpatients at Al-Babtain Center for Burns and Plastic Surgery, Ibn Sina Hospital, Kuwait spanning over a period of 6 years from June 1992 to June 1998, 102 developed clinically and microbiologically proven septicaemia. Only 15 out of them had either single or multiple episodes of septicaemia due to Pseudomonas aeruginosa and were studied during their stay in the hospital. Five of them were males and 10 females, with a mean age of 26 years (range 3-51 years) and mean total body surface area of burns (TBSA) of 66% (range 25-90%). All of them had flame burns and resuscitation was found to be difficult in eight patients either due to delayed hospitalization or accompanied inhalation injury. Seven patients were intubated, four due to inhalation injury and three for septicaemic complications. Among the 15 patients under study, a total of 36 septicaemic episodes were detected of which 21 were due to P. aeruginosa. This organism was found in the first episodes in nine patients, in second episodes in six, in third episodes in three and fourth, fifth and sixth episodes in one patient, each at a variable postburn day. Ten patients had 38 sessions of excision and skin grafting, six of them survived. Nine of the 15 patients under study died due to septicaemia, but only six of them had P. aeruginosa as the last isolate. Except for one, all patients had > 40% TBSA burn, two had difficult resuscitation and four were intubated. The day of death varied between 3 to 52 days postburn (mean 19 days). This study showed that females with flame burns are susceptible to P. aeruginosa septicaemia. Difficult resuscitation and intubation also proved to be important risk factors. Septicaemia could occur quite early in the postburn days and the mortality due to this organism was quite high. Early excision and grafting with other effective management may result in a better outcome.     

Rifampicin as an adjunct to vancomycin therapy in MRSA septicaemia in burns

Rifampicin has been successfully used as an adjunct to vancomycin therapy in several clinical conditions of MRSA infections such as endocarditis, ventriculoperitoneal shunts and septicaemia. However, very little information is available in the literature regarding its use in MRSA septicaemia in burns. The present prospective study was conducted to evaluate the efficacy of rifampicin as an adjunct therapy in burn cases with MRSA septicaemia not responding well to vancomycin. Fourteen out of 36 MRSA septicaemia patients with burns who either did not or only partially responded to therapeutic doses of vancomycin within 5-6 days were treated with rifampicin as an adjunct therapy (600 mg, i.v., o.d) for 5 days during the study period between January 1995 to December 1998. All the patients had burns due to flame and the TBSA varied between 20-90% with a mean of 64%. Eleven patients had deep and three had mixed burns. MRSA septicaemic episodes usually followed 2 3 days of detection of the organism in burn wounds. All the isolates were sensitive to vancomycin with an MIC of < or = 1.0 mg/L and were treated with vancomycin, (500 mg, i.v., 6 hourly). The serum vancomycin levels in all the patients were within the therapeutic range. However, blood cultures still remained positive even after 5-6 days of therapy. Institution of rifampicin, as an adjunct to vancomycin therapy to which the MRSA isolates were susceptible, showed a dramatic clinical response and survival of grafts. Thirteen patients survived and one died who had 70% deep burns and blood cultures revealed a multiresistant Acinetobacter in addition to MRSA. The present study thus confirms the efficacy of clinical use of rifampicin as an adjunct in vancomycin nonresponding cases of MRSA septicaemia in burns.     

Serum esterase inhibition in birds: A nondestructive biomarker to assess organophosphorus and carbamate contamination

With the aim of proposing a nondestructive biomarker for monitoring the toxicological risk to birds of exposure to the organophosphorus insecticide azamethiphos and the carbamate insecticide methomyl, laboratory studies were performed on serum B esterases in Japanese quail (Coturnix coturnix japonica). The birds received two single dose treatments of each compound (azamethiphos and methomyl), i.e., 50 mg/kg and 250 mg/kg respectively. In the first treatment, serum butyrylcholinesterase (BChE) and carboxylesterase (CbE) were drastically inhibited in the azamethiphos-treated group, 24 h after the dose. No inhibition was detected for BChE and CbE activities in the methomyl-treated group, 24 h after the dose. In the second treatment, the birds died or were sacrified 3 h after the dose. Serum BChE and brain acetylcholinesterase (AChE) were strongly inhibited after treatment with both insecticides. Serum CbE, hepatic microsomal CbE and 7-ethoxyresorufin dealkylation activities were also inhibited. A statistically significant correlation between serum BChE and brain AChE was found at lethal and sublethal doses of these xenobiotics. The experimental results indicate that the nondestructive biomarker BChE can give an early qualitative and semi-quantitative warning of the toxic effects of organophosphate and carbamate insecticides in birds.     

Liquid ammonia injury

The toxic effects of a gas depend on the time of exposure, concentration and its chemical nature. Pressurized liquids and gases exert an additional cold thermal injury and this may complicate the clinical picture. A patient who had an accidental exposure to liquid ammonia over a prolonged period, manifesting in cutaneous, respiratory and ocular damage in addition to a severe cold thermal injury (frostbite) with a fatal outcome is presented. The patient had flaccid quadriparesis and episodes of bradycardia, which has not been reported previously. These manifestations raise the possibility of the systemic toxicity in patients with prolonged exposure to ammonia.     

Últimos avances sobre los tumores pancreáticos

Pancreatic cancer (PC) continues to have a very poor prognosis. New epidemiological trials suggest that statins could play a protective role in smokers, while HbsAg-positive hepatitis B virus could be a risk factor. Endoscopic ultrasound (EUS) is the main diagnostic tool for PC, and new technologies associated with this technique have emerged, such as quantitative elastography, intravenous contrasts or, more recently, LASER confocal endomicroscopy. New markers in urine or pancreatic juice have appeared to distinguish between PC and chronic pancreatitis. The role of the “on site” cytopathologist to increase the diagnostic yield of EUS-guided pancreatic sampling is completely supported by new prospective trials and some multicenter studies have been reported that compare the standard cytologic needles with the new procore-histology needles. Regarding cystic pancreatic tumors, most studies have aimed to validate the 2012 Sendai international guidelines and to ascertain predictive factors of malignancy in cystic lesions, mainly intraductal papillary mucinous neoplasm (IPMN). The role of intracystic CEA levels in determining malignancy is challenged. From a therapeutic point of view, EUS-guided radiofrequency ablation of cystic and solid lesions has emerged as a feasible and safe procedure in specific circumstances.     

Intraductal papillary mucinous tumor: diagnostic and therapeutic approach

Primary cystic pancreatic neoplasms are rare tumors, with an approximate prevalence of 10% of cystic pancreatic lesions. Most of these lesions correspond to mucinous cystic neoplasm, serous cystoadenoma and intraductal papillary mucinous tumor (IPMT). IPMT is characterized by diffuse dilatation of the main pancreatic duct and/or side branches with inner defects related to mucin or tumor, or mucin extrusion from a patent ampulla. IPMT has a low potential for malignancy, with a low growth rate, a low rate of metastatic spread and postsurgical recurrence. Over the last few years, major advances have been made in the diagnostic and therapeutic management of this tumor.