Extraction, characterization and properties evaluation of pineapple leaf fibers from Azores pineapple

Pineapple leaves can provide competitive and high-quality fibers for textile purposes. Despite pineapple being cultivated in the Portugues islands there is still a technology gap for the extraction and treatment of Pineapple Leaf Fibers (PALF) in Europe. Since Azorean Pineapple differs significantly from other plants in the bromeliad family, the properties and characterization of its leaf fibers were explored for the first time. Long fibers have been extracted by hand scraping and compared to biological retting at 25 °C for different time periods. It was explored the properties of PALF from plants of different ages (11- and 18-months) and from different zones of the leaves (beginning, middle, and tip). Physical-mechanical properties of Azores PALF were determined, including diameter, linear density, strength, Young's modulus, and elongation at break and characterized by ATR-FTIR, XRD, TGA/DTG, and FESEM to understand their chemical and morphological characteristics. While slight differences were observed between different ages, variations in physical-mechanical properties were notable among fibers extracted from different leaf positions. Extraction of Azores PALF through 25 °C biological retting for 14 days effectively eliminated non-fibrous matter and produced the thinnest and strongest fibers. These fibers ranged between 34.9 and 168.3 μm in diameter, 1.39 and 7.07 tex in linear mass density, 37-993 MPa in tensile strength, 1.0-3.9 % in elongation at break, and 2.4-21.8 GPa in Young's modulus.

Localized Therapeutic Approaches Based on Micro/Nanofibers for Cancer Treatment

Cancer remains one of the most challenging health problems worldwide, and localized therapeutic approaches based on micro/nanofibers have shown potential for its treatment. Micro/nanofibers offer several advantages as a drug delivery system, such as high surface area, tunable pore size, and sustained release properties, which can improve drug efficacy and reduce side effects. In addition, functionalization of these fibers with nanoparticles can enhance their targeting and therapeutic capabilities. Localized delivery of drugs and/or other therapeutic agents via micro/nanofibers can also help to overcome the limitations of systemic administration, such as poor bioavailability and off-target effects. Several studies have shown promising results in preclinical models of cancer, including inhibition of tumor growth and improved survival rates. However, more research is needed to overcome technical and regulatory challenges to bring these approaches to clinical use. Localized therapeutic approaches based on micro/nanofibers hold great promise for the future of cancer treatment, providing a targeted, effective, and minimally invasive alternative to traditional treatments. The main focus of this review is to explore the current treatments utilizing micro/nanofibers, as well as localized drug delivery systems that rely on fibrous structures to deliver and release drugs for the treatment of cancer in a specific area.

Exploring the microbiome, antibiotic resistance genes, mobile genetic element, and potential resistant pathogens in municipal wastewater treatment plants in Brazil

Wastewater treatment plants (WWTPs) have been widely investigated in Europe, Asia and North America regarding the occurrence and fate of antibiotic resistance (AR) elements, such as antibiotic resistance genes (ARGs), mobile genetic elements (MGEs) and antibiotic resistant bacteria and pathogens. However, monitoring data about AR elements in municipal WWTPs in Brazil are scarce. This study investigated the abundance of intI1, five ARGs (sul1, tetA, blaTEM, ermB and qnrB) and 16S rRNA in raw and treated wastewater of three WWTPs, using different sewage treatments named CAS (Conventional activated sludge), UASB/BTF (UASB followed by biological trickling filter) and MAS/UV (modified activated sludge with UV disinfection stage). Bacterial diversity and the presence of potentially pathogenic groups were also evaluated, and associations between genetic markers and the bacterial populations were presented. All WWTPs decreased the loads of genetic markers finally discharged to receiving water bodies and showed no evidence of being hotspots for antimicrobial resistance amplification in wastewater, since the abundances of intI1 and ARGs within the bacterial population were not increased in the treated effluents. UASB/BTF showed a similar performance to that of the CAS and MAS/UV, reinforcing the sanitary and environmental advantages of this biological treatment, widely applied for wastewater treatment in warm climate regions. Bacterial diversity and richness increased after treatments, and bacterial communities in wastewater samples differed due to catchment areas and treatment typologies. Potential pathogenic population underwent considerable decrease after the treatments; however, strong significant correlations with intI1 and ARGs revealed potential multidrug-resistant pathogenic bacteria (Aeromonas, Arcobacter, Enterobacter, Escherichia-Shigella, Stenotrophomonas and Streptococcus) in the treated effluents, although in reduced relative abundances. These are contributive results for understanding the fate of ARGs, MGEs and potential pathogenic bacteria after wastewater treatments, which might support actions to mitigate their release into Brazilian aquatic environments in the near future.

Protective Multifunctional Fibrous Systems Based on Natural Fibers and Metal Oxide Nanoparticles

In recent years, an unprecedented increase in the development of products and technologies to protect the human being has been observed. Now, more than ever, the world population is exposed to several threats, harmful to their well-being and health. Chemical and biological hazardous agents stand out as one of the biggest threats, not only for the military forces, but also for the civilians. Consequently, it's essential to develop personal protective systems that are able to protect their user, not only passively, but actively, being able to detect, adsorb, degrade and decontaminate pesticides, pollutants, microorganisms and most importantly: chemical/biological warfare agents. One recent strategy for the development of active fibrous structures with improved functions and new properties is their functionalization with nanoparticles (NPs), especially metal oxides. Although their known effectiveness in the decomposition of harmful agents, the NPs could also include other functionalities in the same structure using low quantities of material, without adding extra weight, which is of huge importance for a soldier in the battlefield. The use of natural fibers as the substrate is also very interesting, since this material is a much sustainable alternative when compared to synthetic ones, also providing excellent properties.

The Potential of Graphene Nanoplatelets in the Development of Smart and Multifunctional Ecocomposites

Graphene and its derivatives have shown outstanding potential in many fields and textile/composites industry are not an exception. Giving their extraordinary properties, Graphene Nanoplatelets (GNPs) are excellent candidates for providing new functionalities to fibers and composites. In this work, natural fabrics (flax) were functionalized with chitosan (CS) based polymeric formulations of GNPs to develop fibrous systems with electrical properties as well as other functionalities. One of the greatest disadvantages of using carbon-based materials for fabrics’ impregnation is their difficult dispersion. Therefore, several polymers were used as matrices, binding and dispersive agents including chitosan, polyethylene glycol (PEG), and glycerol. All the systems were characterized using several techniques that demonstrated the presence and incorporation of the GNPs onto the composites. Besides their characterization, considering their use as smart materials for monitoring and sensing applications, electrical properties were also evaluated. The highest value obtained for electrical conductivity was 0.04 S m⁻¹ using 2% of GNPs. Furthermore, piezoresistive behavior was observed with Gauge Factor (GF) of 1.89 using 0.5% GNPs. Additionally, UV (ultraviolet) protection ability and hydrophobicity were analyzed, confirming the multifunctional behavior of the developed systems extending their potential of application in several areas.

Impact of microaeration bioreactor on dissolved sulfide and methane removal from real UASB effluent for sewage treatment

Two bioreactors were investigated as an alternative for the post-treatment of effluent from an upflow anaerobic sludge blanket (UASB) reactor treating domestic sewage, aiming at dissolved sulfide and methane removal. The bioreactors (R-control and R-air) were operated at different hydraulic retention times (HRT; 6 and 3 h) with or without aeration. Large sulfide and methane removal efficiencies were achieved by the microaerated reactor at HRT of 6 h. At this HRT, sulfide removal efficiencies were equal to 61% and 79%, and methane removal efficiencies were 31% and 55% for R-control and R-air, respectively. At an HRT of 3 h, sulfide removal efficiencies were 22% (R-control) and 33% (R-air) and methane removal did not occur. The complete oxidation of sulfide, with sulfate formation, prevailed in both phases and bioreactors. However, elemental sulfur formation was more predominant at an HRT of 6 h than at an HRT of 3 h. Taken together, the results show that post-treatment improved the anaerobic effluent quality in terms of chemical oxygen demand and solids removal. However, ammoniacal nitrogen was not removed due to either the low concentration of air provided or the absence of microorganisms involved in the nitrogen cycle.

Performance and bacterial diversity of bioreactors used for simultaneous removal of sulfide, solids and organic matter from UASB reactor effluents

Two bioreactors were investigated as an alternative to post-treatment of effluent from an upflow anaerobic sludge blanket (UASB) reactor treating domestic sewage, with an aim of oxidizing sulfide into elemental sulfur, and removal of solid and organic material. The bioreactors were operated at different hydraulic retention times (HRTs) (6, 4, and 2 h) and in the presence or absence (control) of packing material (polypropylene rings). Greater sulfide removal efficiencies - 75% (control reactor) and 92% (packed reactor) - were achieved in both reactors for an HRT of 6 h. Higher organic matter (COD) and solid (TSS) removal levels were observed in the packed reactor, which produced effluent with low COD (100 mg CODL^-1) and TSS concentrations (30 mg TSSL^-1). Denaturing gradient gel electrophoresis results revealed that a metabolically diverse bacterial community was present in both bioreactors, with sequences related to heterotrophic bacteria, sulfur bacteria (Thiocapsa, Sulfurimonas sp., Chlorobaculum sp., Chromatiales and Sulfuricellales), phototrophic purple non-sulfur bacteria (Rhodopseudomonas, Rhodocyclus sp.) and cyanobacteria. The packed reactor presented higher extracellular sulfur formation and potential for elemental sulfur recovery was seen. Higher efficiencies related to the packed reactor were attributed to the presence of packing material and higher cell retention time. The studied bioreactors seemed to be a simple and low-cost alternative for the post-treatment of anaerobic effluent.

Clinical Impact of Surgical Complications in Kidney Transplant Recipients in a Reference Hospital in Salvador, Bahia, Brazil

BACKGROUND

Renal transplantation is the treatment of choice for patients with stage V chronic kidney disease, which does not have contraindications to the procedure and is more cost-effective than dialysis treatments and provides better survival and quality of life.

OBJECTIVE

The objective of this study was to evaluate the incidence of postoperative complications in kidney transplant recipients in a reference hospital.

METHODOLOGY

This was a descriptive and retrospective study involving the analysis of patient records during hospitalization and outpatient treatment. We analyzed the demographics, clinical indicators, surgical techniques, and postoperative complications.

RESULTS

In the analysis of 147 transplantations, there was a higher incidence of transplantation in female recipients, average age of 37 years with a predominance of cadaveric transplantation. Of all pretransplantation comorbidities, hypertension was the most frequent. The overall incidence of surgical complications was 29.9%, with an incidence of vascular complications of 12.7%, 13.4% of surgical site complications, 8.2% of urologic complications, and 3% of hemorrhagic complications.

DISCUSSION

Vascular complications are serious complications and are associated with increased risk of graft loss (relative risk, 8.4), particularly arterial thrombosis. Patients with ureteral anastomosis using Lich-Gregoir technique showed lower urologic complications compared with patients with anastomosis by Leadbetter-Politano technique.

CONCLUSION

Surgical complications have different clinical effects, depending on their category. The vascular complications are associated with graft lost.

Bacterial community involved in the nitrogen cycle in a down-flow sponge-based trickling filter treating UASB effluent

The bacterial community composition of a down-flow sponge-based trickling filter treating upflow anaerobic sludge blanket (UASB) effluent was investigated by pyrosequencing. Bacterial community composition considerably changed along the reactor and over the operational period. The dominant phyla detected were Proteobacteria, Verrucomicrobia, and Planctomycetes. The abundance of denitrifiers decreased from the top to the bottom and it was consistent with the organic matter concentration gradients. At lower loadings (organic and nitrogen loading rates), the abundance of anammox bacteria was higher than that of the ammonium-oxidizing bacteria in the upper portion of the reactor, suggesting that aerobic and anaerobic ammonium oxidation occurred. Nitrification occurred in all the compartments, while anammox bacteria prominently appeared even in the presence of high organic carbon to ammonia ratios (around 1.0-2.0 gCOD gN(-1)). The results suggest that denitrifiers, nitrifiers, and anammox bacteria coexisted in the reactor; thus, different metabolic pathways were involved in ammonium removal in the post-UASB reactor sponge-based.

Association between mode of delivery and neonatal deaths and complications in term pregnancy: a cohort study in Brazil

AIM

Aim of the study was analyzing the association between mode of delivery and neonatal mortality/ morbidity in term pregnancy.

METHODS

Cohort study with births of liveborn normally formed fetuses from single term pregnancies in a public teaching hospital in São Paulo, Brazil, from January 2003 to March 2004 (total of 1471 births). Data were collected from medical records. We defined 'elective caesareans' as those performed before labor. Four analyses were made: caesarean vs. vaginal, elective vs. non elective caesarean, elective caesarean vs. trial of labor, elective caesarean vs. women in labor. Outcomes studied were: neonatal deaths, jaundice, low Apgar score at 5 minutes, prolonged mechanical ventilation, convulsions, meconium aspiration syndrome, obstetrical trauma and late discharge. Adjustments were made for possible confounders. The chi square test was used along with logistic regression for the analyses. A significance level of 5% was assumed.

RESULTS

A significant negative association between elective caesareans and neonatal death was found, neonatal complications taken as a whole and neonatal complications plus deaths. For example, elective caesarean versus women in labor for the outcome any neonatal complication, adjusted odds ratio 0.59; confidence interval 0.31-0.89.

CONCLUSION

The study highlights a significant negative association of elective caesarean and neonatal mortality and morbidity in term pregnancy.

Diversity and dynamics of ammonia-oxidizing bacterial communities in a sponge-based trickling filter treating effluent from a UASB reactor

Changes in ammonia-oxidizing bacterial (AOB) population dynamics were examined in a new sponge-based trickling filter (TF) post-upflow anaerobic sludge blanket (UASB) reactor by denaturating gradient gel electrophoresis (DGGE), and these changes were linked to relevant components influencing nitrification (chemical oxygen demand (COD), nitrogen (N)). The sponge-based packing media caused strong concentration gradients along the TF, providing an ecological selection of AOB within the system. The organic loading rate (OLR) affected the population dynamics, and under higher OLR or low ammonium-nitrogen (NH4(+)-N) concentrations some AOB bands disappeared, but maintaining the overall community function for NH4(+)-N removal. The dominant bands present in the upper portions of the TF were closely related to Nitrosomonas europaea and distantly affiliated to Nitrosomonas eutropha, and thus were adapted to higher NH4(+)-N and organic matter concentrations. In the lower portions of the TF, the dominant bands were related to Nitrosomonas oligotropha, commonly found in environments with low levels of NH4(+)-N. From a technology point of view, changes in AOB structure at OLR around 0.40-0.60 kgCOD m(-3) d(-1) did not affect TF performance for NH4(+)-N removal, but AOB diversity may have been correlated with the noticeable stability of the sponge-based TF for NH4(+)-N removal at low OLR. This study is relevant because molecular biology was used to observe important features of a bioreactor, considering realistic operational conditions applied to UASB/sponge-based TF systems.

Cerebrospinal fluid fistula as the presenting manifestation of pituitary adenoma: case report with a 4-year follow-up

We report the case of a young woman who presented with cerebrospinal fluid (CSF) rhinorrhea due to an undiagnosed and untreated pituitary adenoma. The tumor had extended well beyond sella turcica and caused bony erosion. The patient initially refused surgery and was treated with bromocriptine and a radiation therapy. CSF leakage did not improved and she was submitted to surgery by the transsphenoidal approach with removal of a tumor mass located in sphenoid sinus and sellar region. Origin of the leak was localized and repaired with fascia lata and a lumbar subarachnoid drain was left in place for 5 days. After 4 years she has normal serum PRL levels and no rhinorrhea. The management, complications and mechanisms involved in this rare condition are discussed.

Posterior approach for soft cervical disc herniation: a neglected technique?

BACKGROUND

The ideal approach to the treatment of soft cervical disc herniation remains controversial. Recent reports emphasize several variations of anterior cervical approaches, including the introduction of instrumentation techniques. New issues have been raised and modern neurosurgeons seem to be less familiar with the posterior approach. The objective of this study was to analyze the results obtained by surgical treatment via a posterior approach of soft cervical disc herniation.

METHOD

Fifty-one patients who underwent laminectomy/flavectomy and disc removal for the treatment of soft cervical disc herniation in the period of 1990 to 1999 were analyzed retrospectively. Relief of pain and motor and sensory improvement were the criteria used to measure the success of the procedure.

RESULTS

Most of the patients presented with acute radiculopathy. Radicular involvement was as follows: 25 cases-C7 root, 19 cases-C6 root, 4 cases-C5 root, and 3 cases-C8 root. Total relief of pain was obtained in 49 of 51 patients (96%). Motor improvement was obtained in 35 of 46 patients (76%) and sensory improvement in 22 of 35 patients (62.8%) in the short term. The mean time of hospitalization was 3 days. There was no mortality and no morbidity.

CONCLUSION

The advantage of this method, in selected cases, over the classical anterior approach, is that there is no need for grafting, thus avoiding the additional pain and possible complications at the donor and receptor sites, while obtaining similar results.

[Medulloblastomas: clinical, epidemiological and pathological findings in 28 cases]

We report the clinical, epidemiological and pathological findings of 28 patients with medulloblastoma: 22 were male; age ranged from 1 to 50 years, with a mean of 15 years. The most frequent symptoms and signs were headache (64%) and vomiting (64%). Only one patient showed a desmoplastic medulloblastoma variant, the others showed classical medulloblastomas. Regarding treatment, most patients were submitted to total resection (n=10) or partial tumorectomy (n=7). A low rate of tumoral recurrence was observed, occurring in 21% of the patients (n=6) after 4 years of follow-up. Chemotherapy seemed to contribute to a lower recurrence rate amongst our patients. Our findings are similar to those reported in literature, thus helping to understand the biological behavior of this type of tumor.

Multiple brain abscesses caused by Salmonella typhi: case report

BACKGROUND

Focal intracranial infections caused by Salmonella species are uncommon. The authors report a case of multiple brain abscesses caused by Salmonella typhi.

CASE DESCRIPTION

A 2-month-old girl was admitted to the hospital because of diarrhea, vomiting, fever, and poor feeding. Neurological examination revealed cervical hyperextension and absence of sucking and Moro reflexes. During the next 20 hours she developed complex partial seizures with secondary generalization and alternated irritability with drowsiness. Investigation showed hemoglobin 6.3 g/dl; white blood cell count of 19500/mm3 with a marked shift to the left. The analysis of the cerebrospinal fluid revealed white cell count of 1695/mm3, lymphocytes 61%, protein 300 mg/dl and glucose 6 mg/dl. The patient was treated for acute gastroenterocolitis, sepsis, and meningitis. Blood culture taken on the day of admission showed gram-negative bacilli, later identified as S. typhi. Computed tomography scan demonstrated a lesion in the right parietal lobe compatible with a brain abscess. Follow-up computed tomography after 7 days showed several other lesions with the same features. Surgical drainage of the right parietal lesion was performed on the 13th day, through a burr hole. The patient was discharged 5 weeks after admission without neurological deficit.

CONCLUSION

Bacteremia, sepsis, and meningitis are relatively common in children with Salmonella infection but intracranial abscesses are very rare. Surgical drainage combined with prolonged antibiotic therapy (drug of choice: chloramphenicol) is the best treatment for Salmonella brain abscesses. The possibility of intracranial infection should be considered in patients with Salmonellosis and neurological dysfunction.

[Common iliac artery false aneurysm as complication of lumbar disc hernia surgery. Case report]

Surgery for discogenic disease of lumbar region is a challenging and diverse field. The significance of complications in disc surgery arises from the possibility that failure of primary treatment may lead to a permanently disable patient. The most common iatrogenic lesions in the posterior approach to lumbar disc herniation are neurologic, vascular, enteric, ureteral, and sexual dysfunction. Abramovitz reports that vascular complications of the posterior approach occur in at least 0.1% of cases. The vascular complications may present during surgery as severe bleeding leading to hypotension. The most common late complication is arteriovenous fistula followed by false aneurysms. We describe the case of a 39 year-old woman who was operated on for a lumbar disc herniation in other hospital. She came to us with a persistent pain in lumbar area. A MRI scan of lumbosacral region revealed a paravertebral lesion suggesting abscess. An angiography was performed and showed a false aneurysm of left common iliac artery, which was surgically treated successfully. We discuss the mechanisms of lesion and precautions against vascular ones during lumbar disc surgery.

Epilepsy surgery without invasive EEG. Early results of a new program

A total of 42 patients were submitted to a clinical, behavioural and neuropsychological evaluation with the objective of eventual surgical treatment of epilepsy refractory to the usual clinical therapies. Prolonged video-EEG monitoring, MRI hippocampal volume measurement, lateralization of speech and memory using the amobarbital (Wada) test were used. Of 18 operated cases, 12 were submitted to temporal lobectomy, with a follow-up of 6-30 months; 8 patients had significant improvement in seizures control; 2 patients had partial improvement in seizure frequency and intensity; 2 patients had no improvement in seizure control. One patient underwent right frontal lobectomy with total remission of seizures and 5 had callosotomy with varying degrees of success. There was no mortality. Morbidity included one subdural hematoma, one transient hemiparesis, one episode of mania, one lobar pneumonia and frequent immediately post-operative muscular tension headaches. These early results indicate good results of temporal lobectomy patients investigated through a non-invasive presurgical evaluation.

[Dysembryoplastic neuroepithelial tumor. Case report]

Dysembryoplastic neuroepithelial tumor (DNT) is a relatively new neuroepithelial neoplasm that was first described by Daumas-Duport et al. in 1988. It was incorporated in the revised World Health Organization classification of brain tumors in 1993. The authors present the first case of DNT reported in the Latin-American literature. A 16-year-old woman had been found at age of five years to have complex partial seizures accompanied by secondary generalization. She was treated with various anti-epileptic drugs but always with incomplete control of seizures activity. Neurological examination was normal. Magnetic resonance imaging demonstrated a lesion in the left temporal lobe. She underwent a craniotomy with complete resection of the tumor. Histological study showed atypical neuroglial proliferation characteristic of DNT. Monoclonal antibody immunostaining for glial fibrillary acidic protein and S-100 protein confirmed the glial component, and neuronal specific enolase and synaptophysin emphasized the neuronal component.