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Apoferritin (apoF) is commonly used as a test specimen in single-particle electron cryo-microscopy (cryo-EM), since it consistently produces density maps that go to 3 Å resolution or higher. When we imaged apoF with a laser phase plate (LPP), however, we observed more severe particle-to-particle variation in the images than we had previously thought to exist. Similarly, we found that images of ribulose bisphosphate carboxylase/oxygenase (rubisco) also exhibited a much greater amount of heterogeneity than expected. By comparison to simulations of images, we verified that the heterogeneity is not explained by the known features of the LPP, shot noise, or differences in particle orientation. We also demonstrate that our specimens are comparable to those previously used in the literature, based on using the final-reconstruction resolution as the metric for evaluation. All of this leads us to the hypothesis that the heterogeneity is due to damage that has occurred either during purification of the specimen or during preparation of the grids. It is not, however, our goal to explain the causes of heterogeneity; rather, we report that using the LPP has made the apparent damage too obvious to be ignored. In hindsight, similar heterogeneity can be seen in images of apoF and the 20S proteasome which others had recorded with a Volta phase plate. We therefore conclude that the increased contrast of phase-plate images (at low spatial frequencies) should also make it possible to visualize, on a single-particle basis, various forms of biologically functional heterogeneity in structure that had previously gone unnoticed. HIGHLIGHTS: Phase plates recover low-frequency information with significantly improved SNRLaser phase-plate images reveal unexpected amounts of structural heterogeneityIn retrospect, similar heterogeneity can also be seen in Volta phase-plate imagesParticle heterogeneity produces "structural noise", which may diminish map quality.
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Nanotechnology is rapidly advancing towards the development of applications for sustainable plant growth and photosynthesis optimization. The nanomaterial/plant interaction has been intensively investigated; however, there is still a gap in knowledge regarding their effect on crop seed development and photosynthetic performance. In the present work, we apply a priming procedure with 10 and 50 mg/L Pluronic-P85-grafted single-walled carbon nanotubes (P85-SWCNT) on garden pea seeds and examine the germination, development, and photosynthetic activity of young seedlings grown on soil substrate. The applied treatments result in a distorted topology of the seed surface and suppressed (by 10-19%) shoot emergence. No priming-induced alterations in the structural and functional features of the photosynthetic apparatus in 14-day-old plants are found. However, photosynthetic gas exchange measurements reveal reduced stomatal conductance (by up to 15%) and increased intrinsic water use efficiency (by 12-15%), as compared to hydro-primed variants, suggesting the better ability of plants to cope with drought stress-an assumption that needs further verification. Our study prompts further research on the stomatal behavior and dark reactions of photosynthesis in order to gain new insights into the effect of carbon nanotubes on plant performance.
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Nanotubos de Carbono , Fotossíntese , Pisum sativum , Sementes , Fotossíntese/efeitos dos fármacos , Nanotubos de Carbono/química , Pisum sativum/efeitos dos fármacos , Pisum sativum/metabolismo , Pisum sativum/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Germinação/efeitos dos fármacos , Estômatos de Plantas/efeitos dos fármacos , Poloxâmero/química , Poloxâmero/farmacologia , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , LuzRESUMO
Vertebral fixation, utilizing titanium screws, is a highly prevalent technique employed to address spinal instability. Screw stabilization malfunction due to pedicle screw nuts loosening is rare. Under tightening the internal nut in the pedicle screw head may increase the likelihood of rod movement within the system resulting in severe pain when moving. Our goal is to raise the attention of surgeons when tightening the screws nuts of the screw stabilization because the consequences for the patient can be subsequent additional operations and complications. This report describes a clinical case of a 40-year-old man who underwent three surgeries at different clinics several years ago for disc herniation at the L4-L5 level and screw stabilization at the same level. The patient presents to the neurosurgery clinic of Saint Marina University Hospital with a clinical manifestation of low back pain escalating with movement, with a pain intensity rating of six on the Visual Analogue Scale (VAS). From the CT scan, it was revealed a malfunction in the screw stabilization with loosening of the screw nuts and dislodgement of the rods. Screw stabilization was restored using intraoperative X-ray guidance and following the "two-three click" protocol. The patient was mobilized on the first day after surgery and discharged on the fifth day with neurological improvement (VAS=1). The patient was followed up for a period of six months, and no further complications were observed. Surgeons must use caution while tightening the screw nuts, as not doing so may result in additional surgeries and complications for the patient in the future. The "two-three click" protocol for screw stabilization is an effective method for minimizing the issues associated with inner loosening and rod migration.
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Cystic hydatid disease is a parasitic disease caused by the larvae of the small tapeworm Echinococcus granulosus. It is still a serious public health problem in endemic regions such as the Mediterranean basin, especially in the Balkans. Usually, the complaints caused by the cysts are non-specific and there are rarely abnormalities in routine laboratory tests. The most common is the involvement of the liver. The frequency of isolated kidney involvement, especially in a child, is uncommon. We describe a rare pediatric case of an isolated renal hydatid cyst presenting with a urinary tract infection-like clinical presentation, leading to misdiagnosis and delayed treatment.
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Cerebral arteriovenous malformations (cAVMs) are developmental pathologic lesions of the blood vessels of the brain in which multiple arteries shunt blood directly into the venous drainage network. They are lesions with an unclear etiology and, if left untreated, can bear significant risks of complications such as migraines, seizures, neurological deficits, and intracranial hemorrhages. The diagnosis is based on several imaging methods, with angiography being the primary method. Treatment modalities include microsurgery, radiosurgery, embolization with the intent of obliteration, and various multidisciplinary approaches. We aim to introduce the case of an adult female patient with symptomatic cAVM who underwent partial endovascular embolization of the lesion and evaluate her recovery and the overall reliability of her treatment modality. A 22-year-old female patient has presented to the Neurosurgery Clinic with clinical manifestations with photosensitive seizures, migraines, and a history of sleep disturbances persisting for a period of one year. An appointed MRI and angiography revealed the presence of a glomerular cAVM of the anterior parietal branch of the middle cerebral artery located within the intraparietal sulcus of the left cerebral hemisphere (Spetzler-Martin grade 2). The venous drainage of the malformation led to a loss of nutrients in the surrounding brain parenchyma (a steal phenomenon), causing the seizures. The patient successfully underwent transarterial endovascular embolization with Onyx, which proved to be partial on a postoperative angiography, and refused further embolization procedures. There were no postoperative complications to be mentioned. The patient reported no seizures or sleep disturbances at the 12-month follow-up, with sporadic weak headaches remaining. cAVMs remain a pathology with significant morbidity and mortality when undiagnosed. Symptomatic cAVMs leading to a steal phenomenon and seizures can be reliably managed via endovascular embolization alone when the malformation has an appropriate angioarchitecture, location, size, and a low Spetzler-Martin score. However, further inquiry is required into the use of partial embolization in cases where further multiple-stage embolization procedures are declined and/or complete occlusion of the lesion is unfeasible. This case report emphasizes that partial endovascular embolization can be successfully utilized as a treatment modality for the symptoms caused by a steal phenomenon of the venous drainage of a cAVM, such as seizure disorders and migraines, in the rare instance when multiple-stage embolization is declined by the patient and occlusion of the lesion remains subtotal.
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The development of meningoencephalitis is a result of an inflammation of the meninges and the brain, which can cause neurological sequelae. Cerebellar meningoencephalitis in adult patients is extremely rare and requires special diagnostic approaches. The aim of this report is to present a rare case of meningoencephalitis and evaluate the diagnostic and therapeutic techniques. We present a 45-year-old male patient who has entered the neurosurgery clinic with a severe headache lasting for a month. Neurological status determines intracranial hypertension. Magnetic resonance tomography (MRT) showed evidence of hyperintense lesions with homogenous enhancement in the right hemisphere of the cerebellum. The patient underwent a suboccipital paramedian craniotomy to excise the lesions and for the pathohistological examination of the biopsy material. Biopsy examination found sections expressing an infection process causing chronic meningoencephalitis in the right hemisphere of the cerebellum. The patient was treated postoperatively with cephalothin 2 g every 12 hours for 14 days. Follow-up examinations proved a relief of the symptoms. Meningoencephalitis of the cerebellum and the meninges is a complication that may occur in adulthood, and surgical excision, biopsy examination, and antibiotic therapy are promising methods for managing the disease.
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Awake craniotomy is a surgical procedure that has been gaining significance over the past decades. Neuronavigation is an intraoperative technology that locates tumors and monitors the brain cortex during awake craniotomy. The presence of cerebral low-grade gliomas in the frontal lobe creates a risk of affecting vital centers of the brain cortex during surgery. We present a clinical case of a 42-year-old male patient who entered the neurosurgery clinic with a clinical manifestation of headache for two months. MRI showed evidence of the recurrence of a left frontal glioma. Differential diagnoses of frontal gliomas include metastases, abscesses, and cysts. The pathophysiologic background of the disease is the mutation of neuroglial cells, which leads to an abnormal and uncontrollable proliferation. Under sleep-awake anesthesia, operative treatment was performed through left frontal awake craniotomy under neuronavigation. As a result, a total excision was achieved. Motor functions of the right limbs and speech have been preserved. The patient was mobilized on the day after the intervention. Surgery-related complications were not observed. The patient had relief from the symptoms and was discharged on the fifth day. Awake craniotomy combined with neuronavigation was the most efficient and the least harmful method for the excision of the tumor. For low-grade gliomas localized in the frontal area of the encephalon, awake craniotomy is the only secure option for surgery.
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Intracranial metastasis disease (IMD) has proven to be a frequent secondary occurrence, usually for primary cancers such as lung, breast, and melanoma, which have a high possibility of metastasizing to the brain. Due to the reasons listed above, treatment and early diagnosis are incredibly challenging. In the past decade, medicine has developed much better imaging solutions and radiological and surgical approaches, increasing the postoperative survival prognosis and achieving more time-efficient results. It is still exceptionally difficult to be able to prevent what type of metastasis a patient might develop other than by using the tumor type or subtype. We present a case of a 51-year-old female patient entering the Neurosurgical Clinic at the University Hospital "St. Ivan Rilski" for operative treatment of a second metastatic lesion located on the left parietal lobe in January 2024. She had previously had an operative resection of an initial lesion located on the left temporal lobe in December 2023. Her medical history began in 2015 when her first diagnosis was a breast carcinoma, followed by operative treatment and radio-, chemo-, and targeted therapy. In 2020, due to metastases located in the bones, she had to undergo another treatment with chemotherapy as well as have a total hysterectomy done as a result of another metastasis. The patient did not provide any family history, nor did she confirm any past or current allergies to foods, drugs, etc. Under general inhalation anesthesia, the patient was placed in a park bench position to the right and had a Mayfield head holder applied. Through a left parietal craniotomy and neuronavigation, a tumor formation was revealed with the characteristic of a secondary lesion. A gross total resection was achieved through a microsurgical technique. Postoperatively, there were no further complications observed in the patient, and she was discharged on day five from the hospital with relief of her symptoms.
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Primary hyperparathyroidism (PHPT) is an extremely uncommon cause of cerebral calcification. A male patient, aged 45, was admitted to the neurosurgery clinic with a closed traumatic brain injury, namely a concussion, resulting in symptoms of headache and loss of balance. A CT scan was conducted, which detected bilateral calcifications on the basal ganglia and the tentorium. The blood tests revealed increased levels of serum calcium, phosphate, and parathyroid hormone (PTH), while vitamin D levels were within the normal range. The patient received symptomatic therapy for the cerebral concussion and was referred for further diagnostic procedures. Based on these exams, it was determined that the patient had a parathyroid adenoma, which was responsible for PHPT characterised by increased levels of calcium, phosphate, and PTH. The patient subsequently underwent a successful parathyroidectomy. Half a year following the surgical procedure, the patient remained free of any indications of neurological conditions, and the levels of PTH and calcium in their body were within the expected range. Whenever trying to identify the cause of cerebral calcification, it is important to explore several possible diagnoses. A possible cause that should be taken into account is PHTP.
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Resveratrol could be applied in wound healing therapies because of its antioxidant, anti-inflammatory and antibacterial effects. However, the main limitation of resveratrol is its low aqueous solubility. In this study, resveratrol was included in hydroxypropyl-ß-cyclodextrin complexes and further formulated in Pluronic F-127 hydrogels for wound treatment therapy. IR-spectroscopy and XRD analysis confirmed the successful incorporation of resveratrol into complexes. The wound-healing ability of these complexes was estimated by a scratch assay on fibroblasts, which showed a tendency for improvement of the effect of resveratrol after complexation. The antimicrobial activity of resveratrol in aqueous dispersion and in the complexes was evaluated on methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, and Candida albicans strains. The results revealed a twofold decrease in the MIC and stronger inhibition of the metabolic activity of MRSA after treatment with resveratrol in the complexes compared to the suspended drug. Furthermore, the complexes were included in Pluronic hydrogel, which provided efficient drug release and appropriate viscoelastic properties. The formulated hydrogel showed excellent biocompatibility which was confirmed via skin irritation test on rabbits. In conclusion, Pluronic hydrogel containing resveratrol included in hydroxypropyl-ß-cyclodextrin complexes is a promising topical formulation for further studies directed at wound therapy.
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Cavum vergae (CV) cysts constitute a small proportion of intracranial cysts, and although generally asymptomatic, there are occasional cases where they might exhibit clinical manifestations. We present a clinical case of a 79-year-old female patient who had a clinical manifestation of headache on the occipital side of the head with irradiation to the shoulder girdle as well as numbness, dizziness, visual impairment, sleep disturbances, and tingling in the hands for three months. Vertigo and rightward staggering had been experienced for two weeks. On physical examination, it was discovered that there was smoothed physiological lordosis, restricted and painful movements, and paravertebral muscle rigidity in the cervical region. The patient had bilaterally reduced biceps and triceps reflexes, painful Erb's points, and hypesthesia over the C5 and C6 dermatomes on the right side. The patient had decreased coordination and displayed staggered movement to the right. A CT scan discovered dilated subarachnoid spaces of the convexity and a CV cyst. The patient was prescribed conservative therapy consisting of etoricoxib oral at a dosage of 2 × 60 mg for seven days, tolperisone hydrochloride orally at a dosage of 2 × 150 mg for seven days, pregabalin 75 mg, one pill in the evening for seven days, ozoid (a gel containing ozone) for external application, and vinpocetine 2 × 10 mg orally for two months. Following the conservative treatment, the patient exhibited improvement in her symptoms and no longer had challenges carrying out her daily tasks. Furthermore, six months after the therapy, the patient did not experience any symptoms. Long-term follow-up will be conducted in cases of symptom recurrence or cyst enlargement.
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Raynaud's syndrome is characterized by paroxysmal vasospasm in the digital arterioles, following exposure to cold or stress. Pain, swelling, stiffness, and hypoesthesia are observed as manifestations. The presence of a trophic ulcer is accompanied by a range of severe manifestations. The assaults occur in three distinct phases, namely vasospastic, plethoric, and erythema. Various approaches improve the overall well-being of a patient. It is possible to differentiate between primary and secondary Raynaud's syndrome, the latter being linked to systemic diseases. The application of botulin toxin is commonly indicated in several medical conditions including focal dystonia, spasticity with or without contractures, paraparesis in children with cerebral palsy, multiple sclerosis, brain injuries, involuntary muscle hyperactivity of a non-dystonic nature, pain management, strabismus, nystagmus, sialorrhea, and esthetic medicine. When treating Raynaud's a technique is used with injection at the base of each finger, from the palmar side, which helps with cooling and minimizing discomfort for patients. We present a clinical case of a 70-year-old female patient with Raynaud's syndrome in which we have placed 70E distributed to both hands botulin toxin type A. Improvement in the patient's symptomatology was noticed on day 3, with warming of the hands, lack of swelling, and pain with duration of the effect little over three months. The patient underwent a six-month follow-up following the therapy with botulinum toxin type A, and no indications of recurrence or advancement of Raynaud's syndrome (RS) were seen.
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Differences in pH between the tumour interstitium and healthy tissues can be used to induce conformational changes in the nanocarrier structure, thereby triggering drug release at the desired site. In the present study, novel pH-responsive nanocarriers were developed by modifying conventional niosomes with hexadecyl-poly(acrylic acid)n copolymers (HD-PAAn). Niosomal vesicles were prepared by the thin film hydration method using Span 60, Span 60/Tween 60 and cholesterol as main constituents, and HD-PAA modifiers of different concentrations (0.5, 1, 2.5, 5 mol%). Next, two model substances, a water-soluble fluorescent dye (calcein) and a hydrophobic agent with pronounced antineoplastic activity (curcumin), were loaded in the aqueous core and hydrophobic membrane of the elaborated niosomes, respectively. Physicochemical properties of blank and loaded nanocarriers such as hydrodynamic diameter (Dh), size distribution, zeta potential, morphology and pH-responsiveness were investigated in detail. The cytotoxicity of niosomal curcumin was evaluated against human malignant cell lines of different origins (MJ, T-24, HUT-78), and the mechanistic aspects of proapoptotic effects were elucidated. The formulation composed of Span 60/Tween 60/cholesterol/2.5% HD-PAA17 exhibited optimal physicochemical characteristics (Dh 302 nm; ζ potential -22.1 mV; high curcumin entrapment 83%), pH-dependent drug release and improved cytotoxic and apoptogenic activity compared to free curcumin.
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Aripiprazole (ARZ) is a medication used for the treatment of various diseases such as schizophrenia, bipolar disorder, major depressive disorder, autism, and Tourette's syndrome. Despite its therapeutic benefits, ARZ is characterized by a poor water solubility which provoked the development of various delivery systems in order to enhance its solubility. In the present work, a nanoscale drug delivery system based on N,N-dimethylacrylamide (DMAA) and ß-cyclodextrin triacrylate (ß-CD-Ac3) as potential aripiprazole delivery vehicles was developed. The nanogels were synthesized by free radical polymerization of DMAA in the presence of ß-CD-Ac3 as a crosslinking agent and then loaded with ARZ via host-guest inclusion complexation. The blank- and drug-loaded nanogels were evaluated using different methods. Fourier transform infrared (FTIR) spectroscopy was employed to confirm the incorporation of ß-CD moieties into the polymer network. Dynamic light scattering (DLS) was used to study the size of the developed systems. The samples exhibited a monomodal particle size distribution and a relatively narrow dispersity index. The hydrodynamic diameter (Dh) of the gels varied between 107 and 129 nm, with a tendency for slightly larger particles as the ß-CD-Ac3 fraction increased. Loading the drug into the nanocarrier resulted in slightly larger particles than the blank gels, but their size was still in the nanoscopic range (166 to 169 nm). The release profiles in PBS were studied and a sustained release pattern with no significant burst effect was observed. A cytotoxicity assessment was also conducted to demonstrate the non-toxicity and biocompatibility of the studied polymers.
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The vein of Galen aneurysmal malformation (VGAM) is a rare congenital arteriovenous fistula of the embryonic median prosencephalic vein of Markowski, resulting in its pathological dilation. If left untreated, it can lead to multiple severe complications in the neonatal period, among which obstructive hydrocephalus. We present a case report of a six-year-old male patient with severe status epilepticus and a clinical history of VGAM and obstructive hydrocephalus, diagnosed via an MRI and an MR-angiography. The hydrocephalus was treated via a ventriculostomy at the age of six months, while the VGAM underwent a partial transarterial endovascular embolization when the patient was four years old. The procedures were successful, and there were no significant post-operative complications observed. The epileptic seizures began at a later point and were successfully medicated with valproate. However, they resumed due to a lowering of the medication dosage by the patient's parents. The patient was given a new valproic acid regimen with an appropriate dosage, and his parents reported no further seizures. This case report emphasizes the use of appropriate prenatal and neonatal diagnostic methods for VGAM and explores the nature of the multi-procedural therapy approach towards the pathology and its complications in relation to a possibly idiopathic co-pathology, namely epilepsy.
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Primary tumors in the central nervous system, known as meningiomas, are frequently found and constitute a substantial proportion of tumor cases. Although generally benign, there are occasional cases where they might exhibit malignant characteristics. Anaplastic meningioma is a rare subtype of malignant meningiomas, representing only a small proportion of cases. We present the case of a 70-year-old female patient who presented to the Neurosurgery Clinic of University Hospital "Saint George" with clinical manifestations of monocular vision and blurry vision in the right eye for three months. On physical examination, unilateral ptosis and mydriasis were noted in the left eye. MRI revealed an extra-axial mass located supratentorial in the left temporopolar region affecting the wing of the left sphenoidal bone, invading the cavernous sinus, suppressing the left and right optic nerves, and involving the left orbit. Operative treatment was performed through a left pterional craniotomy and resection of the tumor mass by microsurgical technique. The subdural, epidural, and intraorbital mass were resected. Total removal of the tumor was not achievable and subtotal resection was performed. Pathology results showed that the tumor mass was anaplastic meningioma. Surgery-related complications were not observed. Postoperatively, the patient was mobilized on the day after intervention and the control CT scan showed no ischemic or hemorrhagic events. The patient experienced relief in her symptoms and was discharged on the fifth day. The patient underwent radiation therapy, resulting in the complete removal of the left tumor in the cavernous sinus. After six months, no tumor recurrence was found, and a long-term follow-up is planned to monitor for possible recurrence.
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Background Traumatic brain injury (TBI) and spinal cord injury (SCI) are leading causes of morbidity and mortality in pediatric patients. However, the epidemiology of pediatric brain and spine injuries in Bulgaria is poorly documented. This study aims to analyze and identify the prevalence, causes, and trends of traumatic brain and spinal cord injuries in pediatric patients during the period of 1st June 2022 to 30th June 2023. Methods A retrospective study was conducted on the medical records of patients under 18 years of age who visited the emergency department of University Multiprofile Hospital for Active Treatment (UMHAT) Burgas, Bulgaria between 1st June 2022 and 30th June 2023. The incidence and etiology were stratified by age, gender, and anamnesis. Data processing and analysis were performed with the statistical package IBM SPSS v. 26.0 (IBM Corp., Armonk, NY, USA), and graphical analysis with MS Office Excel 2016 (Microsoft, Redmond, WA, USA). Means ± standard deviation and 95% confidence interval were calculated. All p-values less than 0.05 were considered indicative of statistical significance. Results Data for patients aged <18 years, admitted to the emergency department (ED) of UMHAT Burgas, Bulgaria from 1st June 2022 to 30th June 2023 were analyzed (n=38504). Of these patients, 32% were children (n=13857). One hundred thirty-four (0.3%) of the pediatric patients were hospitalized in the neurosurgical ward, and 4653 (10.7%) were hospitalized in other wards. Of the analyzed patients, 89 are boys (66.4%), 45 are girls (33.6%) (male-female ratio 2:1) and the mean age of the patients with a head trauma was 8.07 years old. The average number of patients by diagnosis is 13.4±35.37. The largest percent are patients with brain concussion (85.07%, n=114), followed by contusion of the nerve roots in the lumbar region or late contusion wound of the head (with 2.99% each, n=4); hydrocephalus or skull fracture (with 2.24% each, n=3); contusion of the nerve roots in the thoracic region (1.49%, n=2); and fracture at Th9 vertebrae, fracture at C2 vertebrae, brain trauma or brain tumor (with 0.75% each, n=1). The average number of patients by anamnesis is 13.2±17.99. The largest percent are patients who fall from their own height (44.78%, n=60); followed by falls from height (20.90%, n=28); car accident (7.46%, n=10); injured by fight, fall from a bicycle or incident during a football game (with 5.97% each, n=8); fall from electric scooter (4.48%, n=6); hit in the closet (2.99%, n=4); and finally from bike accident or hit by a rock (with 0.75% each, n=1). From 134 hospitalized patients in neurosurgery, 114 (85.07%) did not require surgical treatment and were treated with conservative treatment and 20 (14.93%) were treated surgically. Conclusion In conclusion, this study highlights a significant burden of pediatric traumatic brain and spinal injuries in Bulgaria. The majority of cases were managed conservatively, emphasizing the need for preventive measures.
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Natural and synthetic polymers are a versatile platform for developing biomaterials in the biomedical and environmental fields. Natural polymers are organic compounds that are found in nature. The most common natural polymers include polysaccharides, such as alginate, hyaluronic acid, and starch, proteins, e.g., collagen, silk, and fibrin, and bacterial polyesters. Natural polymers have already been applied in numerous sectors, such as carriers for drug delivery, tissue engineering, stem cell morphogenesis, wound healing, regenerative medicine, food packaging, etc. Various synthetic polymers, including poly(lactic acid), poly(acrylic acid), poly(vinyl alcohol), polyethylene glycol, etc., are biocompatible and biodegradable; therefore, they are studied and applied in controlled drug release systems, nano-carriers, tissue engineering, dispersion of bacterial biofilms, gene delivery systems, bio-ink in 3D-printing, textiles in medicine, agriculture, heavy metals removal, and food packaging. In the following review, recent advancements in polymer chemistry, which enable the imparting of specific biomedical functions of polymers, will be discussed in detail, including antiviral, anticancer, and antimicrobial activities. This work contains the authors' experimental contributions to biomedical and environmental polymer applications. This review is a vast overview of natural and synthetic polymers used in biomedical and environmental fields, polymer synthesis, and isolation methods, critically assessessing their advantages, limitations, and prospects.
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Several biologically active compounds involved in the green synthesis of silver and gold nanoparticles have been isolated from snail mucus and characterized. This paper presents a successful method for the application of snail mucus from Cornu aspersum as a bioreducing agent of copper sulfate and as a biostabilizer of the copper oxide nanoparticles (CuONPs-Muc) obtained. The synthesis at room temperature and neutral pH yielded nanoparticles with a spherical shape and an average diameter of 150 nm. The structure and properties of CuONPs-Muc were characterized using various methods and techniques, such as ultraviolet-visible spectroscopy (UV-vis), high-performance liquid chromatography (HPLC), one-dimensional polyacrylamide gel electrophoresis (1D-PAGE), up-conversion infrared spectroscopy Fourier transform (FTIR), scanning electron microscopy combined with energy dispersive spectroscopy (SEM/EDS), Raman spectroscopy and imaging, thermogravimetric analysis (TG-DSC), etc. Mucus proteins with molecular weights of 30.691 kDa and 26.549 kDa were identified, which are involved in the biogenic production of CuONPs-Muc. The macromolecular shell of proteins formed around the copper ions contributes to a higher efficiency of the synthesized CuONPs-Muc in inhibiting the bacterial growth of several Gram-positive (Bacillus subtilis NBIMCC2353, Bacillus spizizenii ATCC 6633, Staphylococcus aureus ATCC 6538, Listeria innocua NBIMCC8755) and Gram-negative (Escherichia coli ATCC8739, Salmonella enteitidis NBIMCC8691, Salmonella typhimurium ATCC 14028, Stenotrophomonas maltophilia ATCC 17666) bacteria compared to baseline mucus. The bioorganic synthesis of snail mucus presented here provides CuONPs-Muc with a highly pronounced antimicrobial effect. These results will expand knowledge in the field of natural nanomaterials and their role in emerging dosage forms.
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The presented case report demonstrates the successful operative treatment of a patient with thymic carcinoma located in the anterior mediastinum, infiltrating the vena cava, and affecting the upper lobe of the left lung. Our multidisciplinary approach, incorporating various operative techniques, proved effective in treating this type of pathology. The Clinic for Thoracic Surgery at UMHAT Kaspela, Plovdiv admitted a 72-year-old female patient due to complaints related to her cardiovascular and respiratory systems. The patient presented with symptoms such as chest pain, shortness of breath, cough with expectoration, and the presence of blood in her sputum. Additionally, the patient exhibited an increased temperature and experienced shortness of breath at rest. Extensive imaging and diagnostic studies were performed, including computed axial tomography of the chest with contrast material, echocardiography, functional breathing tests, and laboratory tests. The clinical board unanimously agreed that operative treatment was necessary, and the techniques used included robot-assisted surgery and median sternotomy. A low-differentiated carcinoma was identified during the surgical intervention and confirmed through patho-anatomical examination (frozen section) and permanent histological preparation. Immunohistochemical examination revealed that the immunophenotype of the tumor corresponds to thymic neuroplastic squamous cell carcinoma (poorly differentiated). The patient had a smooth postoperative period and was discharged in a satisfactory general condition.