Cyto-histopathological and protein polymorphism alterations in five populations of Nile tilapia (Oreochromis niloticus) as biomonitor for water heavy metal pollution.

Cytological, histopathological and sodium dodecyl sulphate polyacrylamide gel analyses were carried out on five populations of common Nile tilapia fish (Oreochromis niloticus) occurring in five sites - River Nile (reference site), Bahr Yusef canal, Ibrahimia canal, Irrigation drain and El Moheet drain of El Minia Province, Egypt - to evaluate the usability of Nile tilapia as a biomonitor for water heavy metal contaminants. Water surface samples were collected from the five sites, and lead (Pb) concentration was shown to surpass the limits defined by WHO. Ni and Cd levels were shown to be elevated in Ibrahimia canal samples. Moreover, the concentration of heavy metals in fish muscles collected from Bahr Yusef canal and El Moheet drain was the highest in comparison with those of the other water sites. Cytological examinations of blood smears showed not only a significant percentage of micronuclei in Irrigation drain population but also a significant percentage of binucleated cells in Ibrahimia canal and El Moheet drain populations. In addition, pathological alteration was observed in blood cells, especially in samples collected from Irrigation drain and El Moheet drain. Histopathological changes were strongly observed in the liver and the kidneys of El Moheet and Irrigation drain population. Moreover, total protein band pattern profiles showed extra bands in both Ibrahimia canal and Irrigation drain more than that recorded for the River Nile population. In conclusion, cyto-histopathological and total protein band pattern results confirmed that O. niloticus responds sensitively to the excess of heavy metals present in the water.

Purification and characterization of bacteriocins-like inhibitory substances from food isolated Enterococcus faecalis OS13 with activity against nosocomial enterococci.

Nosocomial infections caused by enterococci are an ongoing global threat. Thus, finding therapeutic agents for the treatment of such infections are crucial. Some Enterococcus faecalis strains are able to produce antimicrobial peptides called bacteriocins. We analyzed 65 E. faecalis isolates from 43 food samples and 22 clinical samples in Egypt for 17 common bacteriocin-encoding genes of Enterococcus spp. These genes were absent in 11 isolates that showed antimicrobial activity putatively due to bacteriocins (three from food, including isolate OS13, and eight from clinical isolates). The food-isolated E. faecalis OS13 produced bacteriocin-like inhibitory substances (BLIS) named enterocin OS13, which comprised two peptides (enterocin OS13α OS13ß) that inhibited the growth of antibiotic-resistant nosocomial E. faecalis and E. faecium isolates. The molecular weights of enterocin OS13α and OS13ß were determined as 8079 Da and 7859 Da, respectively, and both were heat-labile. Enterocin OS13α was sensitive to proteinase K, while enterocin OS13ß was resistant. Characterization of E. faecalis OS13 isolate revealed that it belonged to sequence type 116. It was non-hemolytic, bile salt hydrolase-negative, gelatinase-positive, and sensitive to ampicillin, penicillin, vancomycin, erythromycin, kanamycin, and gentamicin. In conclusion, BLIS as enterocin OS13α and OS13ß represent antimicrobial agents with activities against antibiotic-resistant enterococcal isolates.

Coupling chromatin structure and dynamics by live super-resolution imaging.

Chromatin conformation regulates gene expression and thus, constant remodeling of chromatin structure is essential to guarantee proper cell function. To gain insight into the spatiotemporal organization of the genome, we use high-density photoactivated localization microscopy and deep learning to obtain temporally resolved super-resolution images of chromatin in living cells. In combination with high-resolution dense motion reconstruction, we find elongated ~45- to 90-nm-wide chromatin "blobs." A computational chromatin model suggests that these blobs are dynamically associating chromatin fragments in close physical and genomic proximity and adopt topologically associated domain-like interactions in the time-average limit. Experimentally, we found that chromatin exhibits a spatiotemporal correlation over ~4 µm in space and tens of seconds in time, while chromatin dynamics are correlated over ~6 µm and last 40 s. Notably, chromatin structure and dynamics are closely related, which may constitute a mechanism to grant access to regions with high local chromatin concentration.

Laser depilation as adjuvant therapy in prevention of recurrence of pilonidal sinus disease: initial experience of a district general hospital in the UK.

INTRODUCTION: Pilonidal disease is a chronic condition involving the sacrococcygeal area. It can have a significant impact on quality of life, social activities and occupation. Surgery is the mainstay of treatment. However, laser depilation has been proposed as an adjunct to surgery and has shown improved results in some studies. We present our experience of laser depilation in the treatment of pilonidal disease in a district general hospital setting in the UK. MATERIALS AND METHODS: A prospectively maintained database of all consecutive patients who received laser depilation after elective surgery for pilonidal disease was analysed. Patients were offered a minimum of two sessions of laser depilation. The primary outcome measure was disease recurrence. Evidence of new symptoms or signs of pilonidal disease after one year from the latest surgical intervention was defined as recurrent disease. Data are presented as medians with interquartile ranges. RESULTS: A total of 64 patients underwent laser depilation after elective surgery between 1 June 2013 and 1 June 2018; 57 were eligible for final analysis. Sixty-five per cent of patients received six or more sessions of laser treatment. There were no short- or long-term complications related to laser depilation. Patients who had more than two sessions of laser depilation showed an improved recurrence rate. Overall, recurrence rate in our series was 12% at a median follow-up of 172 weeks. CONCLUSION: Laser depilation is a safe and effective adjunct to surgery in minimising the recurrence of pilonidal disease. Patients with primary pilonidal disease and those who are undergoing minimally invasive surgery may also benefit from adjuvant laser depilation. Further high-quality control trials are required to assess its efficacy and safety.

Injection safety at primary health care level in south-western Saudi Arabia.

In a study of injection safety in Abha health district, Saudi Arabia, data were collected from 47 physicians and 85 nurses at 24 primary health care centres, using an observation checklist and an interview questionnaire. All centres used individually packed disposable syringes and puncture-proof containers to collect used needles. Needlestick injury in the previous year was reported by 14.9% of physicians and 16.5% of nurses (0.21 and 0.38 injuries/person/year respectively). Logistic regression analysis identified recapping the needle after use (physicians and nurses) and bending the needle before disposal (physicians) as significant risk factors for injury.

Cleavage of growth differentiation factor 15 (GDF15) by membrane type 1-matrix metalloproteinase abrogates GDF15-mediated suppression of tumor cell growth.

Growth differentiation factor 15 (GDF15), a transforming growth factor (TGF)-beta superfamily member, has been cloned from a placenta cDNA library as a gene product that has promoted activation of pro-matrix metalloproteinase (MMP)2 mediated by membrane type (MT)1-MMP. Expression of MT1-MMP in HEK293T cells caused cleavage of the GDF15 mature form at N(252)-M(253) to produce a 6-kDa C-terminal fragment. Treatment of MCF7 cells with GDF15 induced activation of p53 and enhanced expression of p21, which was abrogated by MT1-MMP expression. GDF15 mRNA synthesis was also shown to be induced by treatment of cells with GDF15. Treatment of MCF7 cells with GDF15 caused suppression of cell proliferation. However, proliferation of MCF7 cells transfected with the MT1-MMP gene was not affected by GDF15 treatment, but was suppressed in the presence of the MMP inhibitor BB94. HT1080 cells transfected with the GDF15 gene, which endogenously express MT1-MMP, synthesize a high-level GDF15 precursor form and a low-level mature form, and treatment of cells with BB94 enhanced production of the GDF15 mature form. Consistent with GDF15 production, HT1080 cells transfected with the GDF15 gene proliferated almost equally with control cells, and addition of BB94 effectively suppressed growth of HT1080 cells transfected with the GDF15 gene concomitant with the accumulation of the GDF15 mature form, but not control cells. These results suggest that MT1-MMP contributes to tumor cell proliferation through the cleavage of GDF15, which down-regulates cell proliferation by inducing activation of p53 and p21 synthesis.

Surgical treatment of thoracic and lumbar tuberculosis by anterior interbody fusion and posterior instrumentation.

OBJECTIVE: To evaluate the efficacy and clinical outcome of simultaneous or sequential anterior and posterior surgical approaches in the management of spinal tuberculosis in the form of anterior extirpation of the tuberculous lesion, strut bone grafting of the defect produced and posterior instrumentation for spinal fixation. SUBJECTS AND METHODS: Twenty-two patients who had tuberculosis of the thoracic and lumbar spine with moderate to severe localized kyphosis and variable degrees of neurological deficits were treated at Al Razi Hospital (Kuwait) in the period from 1998 to 2000 by anterior debridement and autogenous strut bone grafting with simultaneous or staged posterior spinal fixation using either USS or SOCON spinal instrumentation. Appropriate antituberculosis treatment was given to all patients for 9-12 months. The postoperative follow-up period was 18 months. RESULTS: Of the 22 cases the average of preoperative kyphosis was 42 degrees. The average of immediate postoperative correction was 27 degrees. At the last follow-up the average correction was 24 degrees and the loss of correction did not exceed 3 degrees. Average fusion times were 5 months for one-segment fusions and 8 months for two-segment fusions. There was no recurrence of the disease in any of the cases. CONCLUSION: Posterior instrumental stabilization and anterior interbody fusion were found to be effective in arresting the disease, correcting kyphotic deformity and maintaining correction until solid spinal fusion.

Adherence to ATS guidelines for hospitalized patients with community-acquired pneumonia.

OBJECTIVE: To compare outcomes of care and antibiotic utilization for community-acquired pneumonia (CAP) throughout a group of not-for-profit hospitals. METHODS: A retrospective chart review of patients from community hospitals with a diagnosis of pneumonia at discharge admitted from December 1997 to May 1998. Data were collected based on American Thoracic Society (ATS) criteria. RESULTS: Medical records of 330 patients were reviewed; mortality was 7%. Using ATS guidelines, 51 (15.5%) patients were not treated with recommended antimicrobial therapy. Of these patients, 14 had nonsevere cases of CAP and 37 cases were severe. Factors found to be associated with in-hospital mortality included nonadherence to ATS guidelines (OR 4.46; 95% CI 1.38 to 14.43), decreased urine output (OR 7.72; 95% CI 1.70 to 35.04), and increasing age (OR 1.06; 95% CI 1.01 to 1.12). Significant predictors of length of stay (LOS) included age, nonadherence to ATS criteria, suspected aspiration, discharge status, low pulse oximetry on admission, decreased urine output, use of vasopressor medications, and interstitial lung disease; More than 80% of patients had at least one culture performed, but only 27.5% of these cultures were positive. The most cpmmonly prescribed antibiotic was cefuroxime injection, representing 25% of the antibiotic orders. CONCLUSIONS: Patients with CAP treated inconsistently with ATS guidelines had a 4.46-d higher risk of inpatient mortality and had significantly longer LOS.

Cytochrome c oxidase inhibition by N-retinyl-N-retinylidene ethanolamine, a compound suspected to cause age-related macula degeneration.

The endogenous lipophilic and cationic compound N-retinyl-N-retinylidene ethanolamine (A2E) is suspected to cause age-related macula degeneration. It inhibits cytochrome c oxidase, detaches proapoptotic proteins from mitochondria, and induces apoptosis in mammalian retinal pigment epithelial cells (M. Suter, C. E. Remé, C. Grimm, A. Wenzel, M. Jäättela, P. Esser, N. Kociok, M. Leist, and C. Richter, 2000, J. Biol. Chem. 275, 39625-39630). The inhibition of cytochrome c oxidase is highly specific for A2E and is observed with the solubilized and reconstituted enzyme. In the dark, inhibition is overcome by cardiolipin or other acidic phospholipids. With illumination, inhibition is stronger, becomes complete with prolonged exposure, and is then no longer abrogated by cardiolipin. Cardiolipin effectively displaces A2E from cytochrome c oxidase, suggesting noncovalent binding of A2E to the enzyme. We conclude that A2E is a potent cytochrome c oxidase-specific inhibitor which interferes with the binding of cytochrome c to cytochrome c oxidase and, in the light, causes persistent modifications of the enzyme.