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Biotreatment of oily sludge and the involved microbial communities, particularly in saline environments, have been rarely investigated. We enriched a halophilic bacterial consortium (OS-100) from petroleum refining oily sludge, which degraded almost 86% of the aliphatic hydrocarbon (C 10 -C 30 ) fraction of the oily sludge within 7 days in the presence of 100 g/L NaCl. Two halophilic hydrocarbon-degrading bacteria related to the genera Chromohalobacter and Halomonas were isolated from the OS-100 consortium. Hydrocarbon degradation by the OS-100 consortium was relatively higher compared to the isolated bacteria, indicating potential synergistic interactions among the OS-100 community members. Exclusion of FeCl 2, MgCl 2 , CaCl 2 , trace elements, and vitamins from the culture medium did not significantly affect the hydrocarbon degradation efficiency of the OS-100 consortium. To the contrary, hydrocarbon biodegradation dropped from 94.1 to 54.4% and 5% when the OS-100 consortium was deprived from phosphate and nitrogen sources in the culture medium, respectively. Quantitative PCR revealed that alkB gene expression increased up to the 3rd day of incubation with 11.277-fold, consistent with the observed increments in hydrocarbon degradation. Illumina-MiSeq sequencing of 16 S rRNA gene fragments revealed that the OS-100 consortium was mainly composed of the genera Halomonas, Idiomarina, Alcanivorax and Chromohalobacter. This community structure changed depending on the culturing conditions. However, remarkable changes in the community structure were not always associated with remarkable shifts in the hydrocarbonoclastic activity and vice versa. The results show that probably synergistic interactions between community members and different subpopulations of the OS-100 consortium contributed to salinity tolerance and hydrocarbon degradation., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Surface seawater, collected from three fishing harbors during different seasons of the years 2015, 2016 and 2017, were assessed for physico-chemical analyses. Results showed that seawater was mainly polluted by hydrocarbons and some heavy metals. Microbial communities' composition and abundance in the studied harbors were performed using molecular approaches. SSCP analysis indicated the presence of Bacteria, Archaea and Eucarya, with dominance of the bacterial domain. Illumina Miseq analysis revealed that the majority of the sequences were affiliated with Bacteria whereas Archaea were detected at low relative abundance. The bacterial community, dominated by Proteobacteria, Bacteroidetes, Planctomycetes, Cyanobacteria, Firmicutes, Actinobacteria and Chloroflexi phyla, are known to be involved in a variety of biodegradation/biotransformation processes including hydrocarbons degradation and heavy metals resistance. The main objectives of this study are to assess, for the first time, the organic/inorganic pollution in surface seawater of Kerkennah Islands harbors, and to explore the potential of next generation marine microbiome monitoring to achieve the planning coastal managing strategies worldwide., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

We studied the biodegradation of oily sludge generated by a petroleum plant in Bahrain by a bacterial consortium (termed as AK6) under different bioprocess conditions. Biodegradation of petroleum hydrocarbons in oily sludge (C 11 -C 29 ) increased from 24% after two days to 99% after 9 days of incubation in cultures containing 5% (w/v) of oily sludge at 40°C. When the nitrogen source was excluded from the batch cultures, hydrocarbon biodegradation dropped to 45% within 7 days. The hydrocarbon biodegradation decreased also by increasing the salinity to 3% and the temperature above 40°C. AK6 tolerated up to 50% (w/v) oily sludge and degraded 60% of the dichloromethane-extractable oil fraction. Illumina-MiSeq analyses revealed that the AK6 consortium was mainly composed of Gammaproteobacteria (ca. 98% of total sequences), with most sequences belonging to Klebsiella (77.6% of total sequences), Enterobacter (16.7%) and Salmonella (5%). Prominent shifts in the bacterial composition of the consortium were observed when the temperature and initial sludge concentration increased, and the nitrogen source was excluded, favoring sequences belonging to Pseudomonas and Stenotrophomonas . The AK6 consortium is endowed with a strong oily sludge tolerance and biodegradation capability under different bioprocess conditions, where Pseudomonas spp. appear to be crucial for hydrocarbon biodegradation., Competing Interests: Author IA was employed by Bahrain Petroleum Company, Bahrain. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Hentati, Abed, Abotalib, El Nayal, Ashraf and Ismail.)

A halotolerant marine strain PHKT of Halomonas venusta was isolated from contaminated seawater as an efficient biosurfactant producer candidate, on low-value substrate (glycerol). The produced biosurfactants (Bios-PHKT) were characterized as lipopeptides molecules, belonging to surfactin and pumilacidin families, by using Thin Layer Chromatography (TLC), Fourier Transform Infrared Spectroscopy (FT-IR) and Tandem Mass Spectrometry (MALDI-TOF/MS-MS). Bios-PHKT has a critical micelle concentration (CMC) of 125 mg/L, and showed a high steadiness against a wide spectrum of salinity (0-120 g/L NaCl), temperature (4-121 °C) and pH (2-12), supporting its powerful tensioactive properties under various environmental conditions. Likewise, the cytotoxic test revealed that the biosurfactant Bios-PHKT, at concentrations lower than 125 µg/mL, was not cytotoxic for human HEK-293 cells since the cell survival is over than 80%. Furthermore, Bios-PHKT lipopeptides showed excellent anti-adhesive and anti-biofilm activities, being able to avoid and disrupt the biofilm formation by certain pathogenic microorganisms. In addition, the biosurfactant Bios-PHKT showed a remarkable anti-proliferative activity towards tumor B16 melanoma cell line. Besides, Bios-PHKT exhibited an excellent in vitro and in vivo wound healing process. In light of these promising findings, Bios-PHKT could be successfully used in different biotechnological applications., (Copyright © 2021 Elsevier Inc. All rights reserved.)

A halotolerant strain CO100 of Staphylococcus sp. was isolated from contaminated sediments taken from the fishing harbour of Sfax, Tunisia, as an efficient hydrocarbonoclastic candidate. Strain CO100 exhibited a high capacity to break down almost 72% of the aliphatic hydrocarbons contained in crude oil (1%, v/v), used as the sole carbon and energy source, after 20 days of culture, at 100 g/l NaCl, 37 °C and 180 rpm. The isolate CO100 displayed also its ability to grow on phenanthrene, fluoranthene and pyrene (100 mg/l), at 100 g/l NaCl. Moreover, the isolate CO100 showed a notable aptitude to synthesize an efficient tensioactive agent namely BS-CO100, on low-value substrates including residual frying oil and expired milk powder, thus reducing the high cost of biosurfactant production. The ESI/MS analysis designated that BS-CO100 belonged to lipopeptide class, in particular lichenysin and iturine members. Critical micelle concentrations of BS-CO100 were varying between 65 and 750 mg/l, depending on of the purity of the biosurfactant and the used carbon sources. BS-CO100 showed a high steadiness against a wide spectrum of pH (4.3-12), temperature (4-121 °C) and salinity (0-300 g/l NaCl), supporting its powerful tensioactive properties under various environmental conditions. Likewise, BS-CO100 exhibited no cytotoxic effect toward human HEK293 cells, at concentrations within 125 and 1000 μg/ml. Furthermore, the biosurfactant BS-CO100 exhibited remarkable anti-adhesive and anti-biofilm activities, being able to avoid and disrupt the biofilm formation by certain pathogenic microorganisms. In addition, BS-CO100 was found to have more potential to remove hydrocarbons from contaminated soils, compared to some chemical surfactants. In light of these promising findings, strain CO100, as well as its biosurfactant, could be successfully used in different biotechnological applications including the bioremediation of oil-polluted areas, even under saline conditions., (Copyright © 2020. Published by Elsevier Ltd.)

A newly marine Halomonas pacifica strain Cnaph3 was isolated, as a naphthalene degrader and biosurfactant producer, from contaminated seawater collected in Ataya's fishing harbor, located in Kerkennah Islands, Tunisia. Chromatography flame ionization detector analysis revealed that 98.8% of naphthalene (200 mg/L) was degraded after 7 days of incubation, at 30 g/L NaCl and 37 °C. Strain Cnaph3 showed also a noticeable capacity to grow on a wide range of aliphatic, aromatic, and complex hydrocarbons. Interestingly, strain Cnaph3 showed a significant potential to produce biosurfactants in the presence of all tested substrates, particularly on glycerol (1%, v/v). Electrospray ionization analysis of the biosurfactant, designated Bios-Cnaph3, suggested a lipopeptide composition. The critical micelle concentration of Bios-Cnaph3 was about 500 mg/L. At this concentration, the surface tension of the water was reduced to 27.6 mN/m. Furthermore, Bios-Cnaph3 displayed interesting stabilities over a wide range of temperatures (4-105 °C), salinities (0-100 g/L NaCl), and pH (2.2-12.5). In addition, it showed promising capacities to remove used motor oil from contaminated soils. The biodegradation and biosurfactant-production potential of the Halomonas sp. strain Cnaph3 would present this strain as a favorite agent for bioremediation of hydrocarbon-contaminated sites under saline conditions., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest regarding the publication of this manuscript., (© King Abdulaziz City for Science and Technology 2020.)

This work aimed at studying the potential of a new hydrocarbonoclastic marine bacterium, Bacillus stratosphericus FLU5, to produce an efficient surface-active agent BS-FLU5. Biosurfactant production was examined on different carbon sources; using the surface tension measurement and the oil displacement test. Strain FLU5 showed its capacity to produce biosurfactants from all tested substrates, in particular the residual frying oil, which is a cheap renewable carbon source alternative, thus minimizing the high cost of producing those surfactants. MALDI-TOF MS/MS analysis confirmed the presence of lipopeptides, which are identified as members of surfactin and pumilacidin series. The critical micelle concentration (CMC) of the purified lipopeptides produced by strain FLU5 was 50 mg/l. At this concentration, the surface tension of the water was reduced from 72 to 28 mN/m. Furthermore, the crude lipopeptides showed an interesting stability against a broad range of pH, temperature and salinity. In addition, the application of BS-FLU5 in oil recovery from hydrocarbons-contaminated soil (used motor oil) showed that it was more effective on the hydrocarbon-remobilization than some tested synthetic surfactants. Interestingly, the biosurfactant BS-FLU5 showed a negligible cytotoxic effect against the mammalian cells HEK293. These results highlight the applicability of the lipopeptides BS-FLU5 in different fields, especially in environmental remediation processes., (Copyright © 2018 Elsevier Inc. All rights reserved.)

This study aims to investigate the ability of a biosurfactant produced by Marinobacter hydrocarbonoclasticus strain SdK644 isolated from hydrocarbon contaminated sediment to enhance the solubilization rate of crude oil contaminated seawater. Phylogenetic analysis shows that strain SdK644 was very closely related to M. hydrocarbonoclasticus with 16S rRNA gene sequence similarity of 97.44%. Using waste frying oil as inducer carbon source, the producing biosurfactant by strain SdK644 was applied to improve crude oil solubilization in seawater. The preliminary characterization of the produced biosurfactant by FT-IR analysis indicates its possible classification in a glycolipids group. Results from crude oil solubilization assay showed that SdK644 strain biosurfactant was 2-fold greater than Tween 80 surfactant in crude oil solubilization and 12-fold higher than seawater control, as shown by GC-MS analysis of aliphatic compounds. Furthermore, this bioactive compound was shown to be nontoxic against Artemia larvae in short-term acute toxicity bioassay. Generally, the results showed the possible use of M. hydrocarbonoclasticus strain SdK644 biosurfactant in bioremediation processes of the marine environments., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Purpose: To perform a subset analysis of survival outcomes in elderly patients with glioblastoma from a randomized phase 3 trial comparing 2 short-course radiation therapy (RT) regimens in elderly and/or frail patients., Methods and Materials: The original trial population included elderly and/or frail patients with a diagnosis of glioblastoma. Patients joined the phase 3, randomized, multicenter, prospective, noninferiority trial; were assigned to 1 of 2 groups in a 1:1 ratio, either short-course RT (25 Gy in 5 fractions, arm 1) or commonly used RT (40 Gy in 15 fractions, arm 2); and were stratified by age (<65 years and ≥65 years), Karnofsky Performance Status (KPS), and extent of surgery. For the subset analysis in this study, only patients aged ≥65 years were evaluated (elderly and frail patients were defined as patients aged ≥65 years with KPS of 50%-70%; elderly and non-frail patients were defined as patients aged ≥65 years with KPS of 80%-100%); 61 of the 98 initial patients comprised the patient population, with 26 patients randomized to arm 1 and 35 to arm 2., Results: In this unplanned analysis, the short-course RT results were not statistically significantly different from the results of commonly used RT in elderly patients. The median overall survival time was 6.8 months (95% confidence interval [CI], 4.5-9.1 months) in arm 1 and 6.2 months (95% CI, 4.7-7.7 months) in arm 2 (P=.936). The median progression-free survival time was 4.3 months (95% CI, 2.6-5.9 months) in arm 1 and 3.2 months (95% CI, 0.1-6.3 months) in arm 2 (P=.706)., Conclusions: A short-course RT regimen of 25 Gy in 5 fractions is an acceptable treatment option for patients aged ≥65 years, mainly those with a poor performance status or contraindication to chemotherapy, which would be indicated in cases of methylated O6 methylguanine-DNA-methyltransferase promoter tumors., (Copyright © 2017 Elsevier Inc. All rights reserved.)

A physico-chemical characterization of seawater taken from the fishing harbour of Sfax, Tunisia, revealed a contamination by organic and inorganic micropollutants. An aerobic marine halotolerant Bacillus stratosphericus strain FLU5 was isolated after enrichment on fluoranthene, a persistent and toxic polycyclic aromatic hydrocarbon (PAH). GC-MS analyses showed that strain FLU5 was capable of degrading almost 45 % of fluoranthene (100 mg l(-1)), without yeast extract added, after 30 days of incubation at 30 g l(-1) NaCl and 37 °C. In addition, the isolate FLU5 showed a remarkable capacity to grow on a wide range of aliphatic, aromatic and complex hydrocarbons. This strain could also synthesize a biosurfactant which was capable of reducing the surface tension of the cell-free medium, during the growth on fluoranthene. The biodegradative abilities of PAHs are promising and can be used to perform the bioremediation strategies of seawaters and marine sediments contaminated by hydrocarbons.

The capacities of a biosurfactant producing and polycyclic aromatic hydrocarbon (PAH) utilizing bacterium, namely, strain 1C, isolated from an Algerian contaminated soil, were investigated. Strain 1C belonged to the Paenibacillus genus and was closely related to the specie Paenibacillus popilliae, with 16S rRNA gene sequence similarity of 98.4 %. It was able to produce biosurfactant using olive oil as substrate. The biosurfactant production was shown by surface tension (32.6 mN/m) after 24 h of incubation at 45 °C and 150 rpm. The biosurfactant(s) retained its properties during exposure to elevated temperatures (70 °C), relatively high salinity (20 % NaCl), and a wide range of pH values (2-10). The infrared spectroscopy (FTIR) revealed that its chemical structure belonged to lipopeptide class. The critical micelle concentration (CMC) of this biosurfactant was about 0.5 g/l with 29.4 mN/m. In addition, the surface active compound(s) produced by strain 1C enhanced PAH solubility and showed a significant antimicrobial activity against pathogens. In addition to its biosurfactant production, strain 1C was shown to be able to utilize PAHs as the sole carbon and energy sources. Strain 1C as hydrocarbonoclastic bacteria and its interesting surface active agent may be used for cleaning the environments polluted with polyaromatic hydrocarbons.

Optimal treatment of recurrent glioblastoma multiforme (rGBM) in elderly and/or frail patients remains virtually unexplored, the best supportive care (BSC) only is routinely administered due to the fatal prognosis. We evaluated the impact of different treatment methods on post-progression survival (PPS) and overall survival (OS) of such patients. Data from 98 elderly and/or frail rGBM patients, treated initially with 1-week or 3-week radiotherapy (RT) within the phase III IAEA study (2010-2013), were analyzed. KPS at relapse and salvage treatment methods were recorded. Kaplan-Meier method was used to estimate PPS and OS for different treatment modalities. Eighty-four patients experienced recurrence: 47 (56%) received BSC, 21 (25%)-chemotherapy (CHT), 8 (9.5%)-surgery, 3 (3.5%)-RT, for 5 (6%) the data was unavailable. Median OS from randomization for all 84 patients was 35 weeks: 55 versus 30 weeks for any treatment versus BSC, p < 0.0001. Median PPS was 15 weeks: 23 weeks with any treatment versus 9 weeks with BSC, p < 0.0001. For local treatment (surgery and/or RT) median PPS was 51 versus 21 weeks for CHT, p = 0.36. In patients with poor KPS (≤60) at relapse median PPS was 9 weeks with BSC versus 21 weeks with any treatment, p = 0.014. In poor KPS patients median PPS for local treatment was 14 weeks versus 21 weeks with CHT, p = 0.88. An active therapeutic approach may be beneficial for selected elderly and/or frail rGBM patients. Poor KPS patients may also benefit from active treatment, but there is no benefit of local treatment over CHT.

Purpose: The optimal radiotherapy regimen for elderly and/or frail patients with newly diagnosed glioblastoma remains to be established. This study compared two radiotherapy regimens on the outcome of these patients., Patients and Methods: Between 2010 and 2013, 98 patients (frail = age ≥ 50 years and Karnofsky performance status [KPS] of 50% to 70%; elderly and frail = age ≥ 65 years and KPS of 50% to 70%; elderly = age ≥ 65 years and KPS of 80% to 100%) were prospectively randomly assigned to two arms in a 1:1 ratio, stratified by age (< and ≥ 65 years old), KPS, and extent of surgical resection. Arm 1 received short-course radiotherapy (25 Gy in five daily fractions over 1 week), and arm 2 received commonly used radiotherapy (40 Gy in 15 daily fractions over 3 weeks)., Results: The short-course radiotherapy was noninferior to commonly used radiotherapy. The median overall survival time was 7.9 months (95% CI, 6.3 to 9.6 months) in arm 1 and 6.4 months (95% CI, 5.1 to 7.6 months) in arm 2 (P = .988). Median progression-free survival time was 4.2 months (95% CI, 2.5 to 5.9) in arm 1 and 4.2 months (95% CI, 2.6 to 5.7) in arm B (P = .716). With a median follow-up time of 6.3 months, the quality of life between both arms at 4 weeks after treatment and 8 weeks after treatment was not different., Conclusion: There were no differences in overall survival time, progression-free survival time, and quality of life between patients receiving the two radiotherapy regimens. In view of the reduced treatment time, the short 1-week radiotherapy regimen may be recommended as a treatment option for elderly and/or frail patients with newly diagnosed glioblastoma., (© 2015 by American Society of Clinical Oncology.)

Background: Sternal arch is a nonspecific clinical signs wich may arise during following of breast cancer, this sign reveals an involvement of internal mammary nodes secondary to breast cancer., Aim: To report a rare event such as a loco-regional sternal or parasternal invasion secondary to locally advanced cases of breast cancer (BC) about a Tunisian series., Methods: We collected retrospectively from 1988 to 2012, 11 cases of BC treated at the Institut Salah Azaiez (ISA) of Tunis, with presence during the disease evolution (initial or at relapse) of a sternal or parasternal swelling. We analyzed their clinical history, clinical and imaging data (CT-scan and/or MRI), stage, time of occurrence, treatment and evolution, Results: All patients were females and their mean age was 46 years varying from 24 to 75 years. The sternal or parasternal swelling was found at diagnosis in 5 cases and on recurrence in 6 patients after a mean free interval of 24 months, > 12 months in 5 cases. The mean clinical tumor size of the primitive BC was 38 mm (24-75 mm) and lesions located in external quadrants in 3 cases and internal or central in 6 cases. Sternal involvement related to large Intrammmary Chain (IMC) adenopathies was diagnosed by CT-scan. 7 patients had synchronous metastases. 9 out of the 11 patients received a locoregional RT and two received chemotherapy (CT)., Conclusion: Sternal or parasternal swelling is a clinical apparent symptom of advanced internal mammary lymph nodes in breast cancer. The first etiologic diagnosis in this context is an advanced internal mammary chain (IMC) node involvement from breast cancer.

Aim: The aim of this study was to determine the characteristics and outcome of patients presenting with clear cell carcinoma (CCC) of the endometrium treated in a single institution., Methods: We reviewed the records of patients treated in the Salah-Azaiz institute for CCC of the endometrium. A histopathological stage was retrospectively assigned to these patients according to the FIGO classification and was compared to the clinical stage. Pathological features were studied in order to determine predictif factors of extrauterine disease extention and failure patterns., Results: 12 patients were included in the study. The mean age at diagnosis was 64 years (50 to 84 yers). Upstaging after surgery was found in 9 patients. 9 patients had extrauterine extension. Deap myometrial invasion was not correlated with extrauterine extension. After a median follw up of 32 months, 4 patients presented with recurrences: one vaginal recurrence, two cases of pelvic and abdominal recurrence and abdominal recurrence in one patient. All recurrences occurred during the first year after surgery. Tumor recurrence was located within the radiation field in one case. Two patients with abdomino-pelvic recurrences progressed despite the association of surgery, radiation therapy and chemotherapy., Conclusion: Extrauterine extension is frequent at diagnosis and not correlated to classical risk factors observed in endometrioid carcinoma. A comptlete surgical staging is necessary for adjuvant treatment. Locoregional and distant recurrences are frequent and have a poor outcome.

The aim of this study was to determine the epidemiological, clinical and anatomopathological aspects of breast cancer in Tunisia. We censored and analyzed all cases of breast cancer newly diagnosed in Tunisia during the year 2004. During that year, 1437 new cases of invasive breast cancer were diagnosed and 35 cases of non invasive breast cancer. There were 1408 women and 29 men. The accrual incidence was 27.1 and the standardized incidence was 28.5. The mean age for women was 51 years. The mean tumour size was 40.8 mm (32.3 mm and 42.5 mm for private and public sectors respectively). Tumour stage was T1 in 12.2% cases, T2 in 46.9% cases, T3 in 11.2% cases and T4 in 24.7% cases. Invasive ductal carcinoma was the most frequent (86,6%) with SBR II grade representing 54.5%. 27.7% of the patients had undergone conservative treatment. There was an unexpected increase of the incidence since 1994 where the standardized incidence was 16.9. We have noticed a moderate decrease of the tumour size of 8 mm during the last decade. This national epidemiological study on breast cancer showed an increase in the incidence of this cancer with a moderate decrease in the clinical tumour size. The relative young mean age of our patients may be explained by the age distribution in our population or by risk factors that may be particular to our country.

Purpose: The aim of this study was to assess the impact of fractionated total body irradiation (F-TBI) on treatment-related mortality (TRM) and relapse in patients who received a non-T-cell-depleted allogeneic stem cell transplantation (ASCT) for hematological malignancies., Materials and Methods: Between March 2003 and December 2004, a total of 24 patients with HLA-identical sibling donors entered this study and received three doses of 3.33 Gy F-TBI separated by 24 h and cyclophosphamide or etoposide., Results: At a median follow-up of 37 months (range 29-47 months), 4 of the 24 patients (16.6%) died of TRM. Relapse occurred in 10 patients at a median of 9 months (range 2-18 months). Overall, 13 of 24 patients (54%) died. Relapse was the most common cause of death (9/13). The 2-year actuarial survival rate was 46% (+/-11%)., Conclusion: In our experience, ASCT conditioned with F-TBI was associated with low TRM but a high early relapse rate in patients with hematological malignancies.