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A fever of unknown origin (FUO) in children is usually described as a fever of at least 8 days duration with no apparent diagnosis after initial investigations, including taking medical history and preliminary laboratory assessment. Infectious diseases are the most common cause of FUO, followed by rheumatologic and neoplastic conditions. In this report, we present a case of a 15-year-old Caucasian boy with a silent past medical history, who presented at our Pediatric ER department with a three-day history of fever, fatigue, and abdominal pain with diarrhoea. Initial laboratory testing and microbiological work-up were non-significant. At hospital admission, a broad infectious diagnostic work-up was pursued, including serologies and polymerase-chain-reaction (PCR) for CMV, EBV, HAV, Parvovirus, Toxoplasma gondii and Adenovirus, all negative. Given mild splenomegaly and linfadenopathy, systemic Juvenile Idiopathic Arthritis (s-JIA) was suspected, as well as Multi-inflammatory Syndrome in Children (MIS-C), but the patient did not meet their main diagnostic criteria. Malignancy was ruled out by a negative bone marrow fine-needle aspiration cytology and whole-body PET-CT scan. On hospital day 8, Brucella was identified on a new set of blood cultures and a combined antibiotic therapy was started with IV Gentamicin plus per os Doxycycline. The patient’s general conditions rapidly improved, and both fever and diarrhoea resolved. A reassessment of the patient’s medical history before discharge revealed exposure to unpasteurized soft cheese in the weeks prior to the onset of symptoms. This case underlines the importance of taking a complete medical history, as well as a full diagnostic work-up to unveil unusual infectious etiologies behind FUO. After the preliminary negative microbiological tests, a connective tissue disease was ruled out (i.e. lack of cutaneous or articular involvement), as well as malignancy, which led to a closer evaluation for infection and the diagnosis of Brucellosis.

Graft Versus Host Disease (GVHD) is a major limitation to the success of allogeneic Hematopoietic Stem Cell Transplantation (HSCT) as Steroid-Refractory (SR) acute GVHD carries poor prognosis due to the absence of an efficacious second-line therapy. Mesenchymal Stem Cells (MSCs) which have immunosuppressive, immunomodulatory, and regenerative properties may become a highly effective therapeutic modality for SR-GVHD in the near future. MSCs have already been approved to treat childhood SR-GVHD in Japan, and they have been conditionally licensed in New Zealand and Canada. It is expected that MSCs will be approved for the treatment of SR-GVHD in adults in Europe, North America, and other parts of the world within a few years. Utilization of the recently introduced techniques including the use of MSC products such as exosomes and Extracellular Vesicles (ECVs) instead of the parent MSCs, robotic manufacturing technology, and genetic engineering of MSCs will ultimately overcome the remaining obstacles facing the widespread utilization of MSCs and their products as therapeutics not only in HSCT but also in other medical fields. The aim of this review is to provide an update on the remarkable progress achieved in the use of MSCs and their products in the field of HSCT.

Mesenchymal Stem Cells (MSCs) have antimicrobial, anti-inflammatory, immunomodulatory, and regenerative potentials. Additionally, utilization of MSCs in the clinical arena has been shown to be safe and well tolerated. Hence, this form of cellular therapy has gained particular attention in the treatment of several infectious disorders and their complications. MSCs have been successfully used in the treatment of the following infections and their complications: bacterial infections including complicated sepsis; viral infections including Human Immunodeficiency Virus (HIV), hepatitis B and C viruses, and Coronavirus disease (COVID-19) complicated by acute respiratory distress syndrome; parasitic infections including schistosomiasis, malaria, and Chagas disease; and mycobacterial infections including tuberculosis. The use of MSCs derived from certain sources and Extracellular Vesicles (ECVs) derived from MSCs has improved their efficacy and reduced their side effects. However, the clinical application of MSCs in the treatment of several infectious diseases still faces real challenges that need to be resolved. The current status of MSCs and the controversies related to their utilization in various infections will be thoroughly discussed in this review. 

Patients with heart failure may live longer if they receive chronic treatment with beta-adrenergic blocking medications. Unresolved are the mechanisms underlying the beneficial effects and if they may be applied to ischemic heart failure. Rats (n = 28) underwent echocardiographic-Doppler exams one and six weeks following a simulated operation or myocardial infarction (MI). After the first echocardiography, rats were randomized to either no therapy or 500 mg/l of propranolol in their drinking water. The noninfected left ventricular (LV) papillary muscles were used to record isometric contractions and intracellular Ca transients simultaneously.Untreated MI rats had a restrictive LV diastolic filling pattern, decreased systolic function (13% ± 2%), and significant LV dilatation (10.6 ± 0.4 mm vs. 8.9 ± 0.3 mm, MI vs. control). The LV chamber diameters of the propranolol-treated MI rats were 10.6 ± 0.5 mm, and systolic performance (13% ± 2%). Higher LV end-diastolic pressures (27 ± 2 mmHg vs. 20 ± 3 mmHg) and a more constrained LV diastolic filling pattern (increased ratio of early to late filling velocities and faster E wave deceleration rate) were seen in the propranolol-treated animals. Papillary muscle contractility in untreated MI rats was lower (1.6 ± 0.3 g mm²). Furthermore, the inotropic response to isoproterenol was attenuated, and Ca transients were extended. During isoproterenol stimulation, beta-adrenergic blocking administration had no effect on force development (1.6 ± 0.3 g mm²) or the length of Ca transients.Rats with postinfarction heart failure receiving chronic propranolol treatment did not have improvements in systolic function or LV remodeling. Propranolol exacerbated LV diastolic pressures and filling patterns. Additionally, there was no discernible improvement in intracellular contractility following treatment, Calcium control, or beta-adrenergic sensitivity in the myocardium that is not infarcted).

A very unusual, interesting, and challenging case of a 24-year-old female who was born with three openings in the neck. The patient had chronic abdominal gaseous distention, recurrent abdominal pain, and constipation since early infancy. The patient presented in emergency with acute painful red, hot, and tender swelling in the left upper cervical area. Laboratory studies showed high inflammatory markers and a provisional diagnosis of abscess with a sinus was made. The patient underwent an emergency incision and drainage. Sinus recurred and a sinogram showed it to be a residual cyst in the left submandibular salivary gland. The total cyst excision was attempted with resultant recurrence and grade IV facial nerve palsy. Post-operatively recurrent infections caused by Methicillin-resistant Staphylococcus aureus (MRSA) required several courses of oral and intravenous broad-spectrum antibiotics with several hospital admissions with no resolution in sight. Subsequent ultrasound and magnetic resonance imaging showed a residual infected cyst, cutaneous sinus, and a fistula opening in the left ear canal. A diagnosis of branchial cyst type II of the first brachial cleft remnant with a fistula was established with bilateral branchial fistulas of the second branchial remnants and the associated colorectal hypoganglionosis based on radiological studies. The patient refused any further operative interventions. Therefore, the option of conservative treatment of hypoganglionosis with holobiotics consisting of prebiotics, probiotics and postbiotics, laxatives, dietary changes, lifestyle modifications, and dietary supplements started. All antibiotics were stopped. These therapies resulted in the resolution of residual first branchial remnants and recurrent MRSA infections with the improvement in the facial nerve palsy from grade V to grade III-IV together with an excellent cosmetic and functional result. The patient is doing well at follow-ups being infection-free for 18 months and repeat contrast-enhanced computed tomogram (CECT) has shown complete resolution of the residual cyst, sinus, and fistula with fibrosis.

Mesenchymal stem cells are heterogenous adult multipotent stromal cells that can be isolated from various sources including bone marrow, peripheral blood, umbilical cord blood, dental pulp, and adipose tissue. They have certain regenerative, anti-inflammatory, immunomodulatory, immunosuppressive, antimicrobial, and other properties that enable them to have several therapeutic and clinical applications including treatment of various autoimmune disorders; role in hematopoietic stem cell transplantation and regenerative medicine; treatment of skin, pulmonary and cardiovascular disorders; treatment of neurological and eye diseases; as well as treatment of various infections and their complications. Different factors including donor age, biological source, route of administration, and signaling pathways have an impact on the functions and consequently the clinical applications of mesenchymal stromal cells. The products of mesenchymal stem cells such as extracellular vesicles and exosomes reproduce the biological effects and most of the therapeutic actions of the parent stem cells. Genetic engineering and the use of specific mesenchymal stromal cell products have improved their clinical efficacy and decreased their adverse effects. However, despite the recent progress in the use of mesenchymal stem cells, the clinical application of these cells in the treatment of several diseases still faces real challenges that need to be resolved. The current status of mesenchymal stem cells and the controversies related to their clinical utilization in various disease conditions will be thoroughly discussed in this review.

Penile cancer, a rare but highly morbid disease, primarily manifests as squamous cell carcinoma (PSCC) originating from the squamous cells of the glandular and preputial skin. Late-stage diagnosis is common due to social stigma, psychological barriers, and nonspecific initial symptoms, resulting in poor overall survival rates, especially in metastatic cases. This case report illustrates a 38-year-old man with advanced metastatic PSCC, showcasing severe systemic manifestations and delayed presentation of the disease. Despite aggressive treatment options, the patient opted for palliative care, succumbing to the disease months after his diagnosis. Risk factors for PSCC include HPV infection, phimosis, chronic inflammation, and lifestyle factors, with higher prevalence in regions of low socioeconomic status. The psychological and sexual burden of penile cancer is significant, impacting patients’ well-being, mental health, and quality of life. In conclusion, efforts to reduce the stigma associated with penile cancer are crucial to prompt early diagnosis and treatment initiation. Encouraging seeking medical attention for symptoms can enhance the chances of recovery and minimize the need for invasive treatments. Addressing the psychosocial impact of the disease is imperative for holistic patient care.

Background: Dysgerminomas, account for only 1% - 2% of all malignant ovarian neoplasms.Objective: This case report aims to present a rare occurrence of dysgerminoma in a pediatric patient, highlighting the clinical characteristics, diagnosis, and management.Case presentation: We present a case of dysgerminoma in a 12-year-old girl who presented with a three-week history of pelvic pain and progressive abdominal swelling. Physical examination revealed a distended abdomen with evident suprapubic fullness, and a palpable abdominopelvic mass measuring approximately 20 weeks in size. Imaging studies confirmed the presence of a solid heterogeneous mass originating from the pelvis. The patient underwent a right salpingo-oophorectomy without complications. Histological examination coupled with an immunohistochemical study confirmed the diagnosis of dysgerminoma. The patient had an uneventful postoperative course and was discharged without adjuvant treatment. Regular follow-up visits, physical examinations, ultrasound scans, and lactate dehydrogenase assays were initiated for monitoring. Conclusion: Prompt recognition and appropriate surgical intervention, followed by regular monitoring, are crucial for optimal outcomes in pediatric dysgerminoma cases.

With the increase in incidence and prevalence of myeloid neoplasms in India, it has become a necessity to understand its molecular mechanisms, acquisition of genomic alterations, and understand its primary and secondary resistance pathways which ultimately impact the decision of therapeutics. The objective of this review is to investigate the molecular aspects of this disease type and identify the biomarkers that help with diagnosis, risk assessment, prognosis, and selecting the best line of treatment for a specific myeloid neoplasm. Advancements and innovations in molecular technologies from simplest Real-Time PCR to high throughput next-generation sequencing have played a vital role in screening the most common mutations and fusions to the novel and rare. Molecular technologies have helped to enumerate the genomic landscape of myeloid malignancies. The understanding of both- the mechanisms and the technology is a strong combination as it has helped revolutionize precision oncology and helped in giving better therapeutic choices with better clinical outcomes. The importance of cellular morphology, clinical symptoms, and molecular pathology in assessing the risk of myeloid malignancies is emphasized and summarized in the review. The review concludes that understanding molecular pathogenesis can be improved by using clinical-pathological-molecular strategies for diagnosis and therapy decision-making.

Thyroid cancer, characterized by the development of malignant tumors in the cells of the thyroid gland, impacts the quality of life and well-being of diagnosed patients. This article explores different aspects of this type of cancer, including everything from its typologies, incidence, causes, and risk factors to symptoms, diagnostic methods, and treatment options. Furthermore, the impact on Health-Related Quality of Life (HRQoL) is addressed, highlighting that, although the prognosis is generally favorable, patients can experience significant negative repercussions. Therefore, the need for further investigation into the priorities of psychological intervention with the population with this problem is emphasized.

The city of Santo Amaro (Bahia, Brazil) gained visibility among the scientific community due to the contamination of the Subaé River by lead and cadmium from the PLUMBUM Mineração e Metalurgia Ltda industry, on the banks of the river in 1956, which produced lead ingots The present work aimed to investigate the adsorption capacity of heavy metals (Pb and Cd) of EPS produced by bacterial species from the Subaé River, for possible future application of these biopolymers in bioremediation processes in areas impacted by the aforementioned heavy metals. Subaé river water was collected for physical-chemical analysis and bacterial isolation. It was verified that all isolated bacteria produced an expressive amount of Exopolysaccharide (EPS). Thus, the optimization of this production in different sugars (sucrose, glucose, and mannitol) and in three different pHs: 5.5; 6.5, and 7.5. All bacteria produced EPS in large quantities and the best sugar was sucrose at pH 7.5. In order to use the EPS for the bioremediation area, the adsorption test of lead and cadmium was carried out by the isolated EPS. 0.5 g of the EPS was dissolved in 50 ml of deionized water, then the solutions of metals, lead acetate, and cadmium sulfate (procedure performed separately) were incubated at 28 °C for 16 h after that period, and were centrifuged. Samples were filtered to separate the insoluble EPS and the filtrates obtained were used in the quantification of the metals by atomic absorption (FAAS- Flame Atomic Absorption Spectrometry). Bacillus spp., Bacillus cereus, Staphylococcus spp., and Serratiamarcescens, all showed tolerance to the tested metals, due to the efficiency in the adsorption capacity of the EPS, and it was possible to distinguish seven genera, Klebsiella pneumonia, Pseudomonas aeruginosa, Lysinibacillus spp. to be used in the bioremediation of environments contaminated with heavy metals.

Background: The age-dependent sporadic form of PD is characterized by the degeneration of dopaminergic (DA) neurons in the Substantia Nigra (SN), gliosis, and vascular changes. Vascular changes may contribute to the onset of the disease and exacerbate the neurodegenerative process, as some vascular changes occur before the onset of neuronal loss. To demonstrate the anti-neuroinflammatory efficacy of a new compound, a water-soluble form of dihydroquercetin (DHQ-WF), we studied the structural changes of microcirculatory vasculature, astroglial GFAP, and vascular endothelial growth factor –A (VEGF-A) mRNA expression in the SN of young and old rats after unilateral nigral treatment by lipopolysaccharide (LPS) and oral administration of DHQ-WF.Materials and methods: The experiments were performed on 18 young (8 weeks - 10 weeks old; 250 g - 320 g) and 18 old (18 months - 19 months old; 390 g - 450 g) male Vistar rats. Young and adult rats from the experimental groups were stereotactically injected with 2 μL LPS solution (LPS from Escherichia coli; 0,01 μL/mL) into one side of the SN. Control young and old rats were similarly injected with 2 μL sterile saline. Half of the animals in both the control and experimental groups (6 animals in each group) received a 2 ml solution containing DHQ-WF at a concentration of 3 mg/ml orally every day. After 8 weeks, brains were harvested and serial cryostat sections were prepared for histochemical (FITC-labeled tomato lectin), immunohistochemical (anti-GFAP Antibody, Cy3 Conjugate) staining, and real-time PCR (mRNA VEGF-A).Results: Eight weeks after LPS injection into the SN, a significant excess of areas occupied by cell bodies and processes of astroglial cells, the density of microcirculatory vessels, and mRNA VEGF-A expression was observed in old animals compared to control old animals and young LPS-treated rats.  Oral administration of DHQ-WF to LPS-treated rats resulted in a significant reduction of these parameters in old animals.Conclusion: Injection of LPS into rat SN induces neuroinflammation and vascular angiogenesis, maximally expressed in old animals.  Administration of DHQ-WF for 8 weeks significantly reduces these LPS-induced changes. DHQ-WF may be an effective treatment for reducing the effects of neuroinflammation in the aging brain.

Endophytic microbes i.e. bacteria, fungi, and actinomycetes live inside the plant tissues without causing any harmful effect on them. Recently, research has been conducted on endophytic microbes to enhance agriculture and environmental sustainability. Endophytes stabilize a close association with their host, which leads to major changes in plant physiology. Endophytic microbes and pathogens use the same strategies for entering the host cell. This condition may create competition between the endophytes and the pathogen. Therefore, host plants develop strategies to allow the entry of specific microorganisms. Additionally, endophytic microorganisms may temper their own genetic structure to survive and avoid the host defence machinery. The plant-endophyte symbionts promote direct and indirect defences to host plants. This plays an essential role in modulating plant defences against various stresses, particularly biotic stress. In this minireview, we highlight the interaction of endophytic microbes with their host.  As well as the role of endophytic microbes in the enhancement of plant defence systems.

Mesenchymal Stromal/Stem Cells (MSCs); which can be isolated from Bone Marrow (BM) in addition to several tissues and body fluids; have the following characteristic features: self-renewal, differentiation into various cell types, plastic adherence, and specific surface markers on flow cytometry [1-3]. 

Background: Patients with acute and chronic leukemia presenting with hyperleukocytosis are at risk of developing leukostasis which has serious and life-threatening complications. Leukapheresis is usually performed to reduce the complications of leukostasis in patients presenting with hyperleukocytosis and clinical manifestations compatible with leukostasis. Methods and materials: A retrospective study of patients with acute and chronic leukemia who received leukapheresis for hyperleukocytosis between the 1st of January 2013 and the 31st of December 2023 at King Fahad Specialist Hospital (KFSH) in Dammam, Saudi Arabia was performed. Results: Over a period of 11 years, a total of 50 patients with acute and chronic leukemia presenting with hyperleukocytosis and clinical manifestations of leukostasis; 32 patients with acute leukemia (AL) and 18 patients with chronic myeloid leukemia (CML); received leukapheresis at our institution. Among the 32 patients with AL who received leukapheresis, 24 patients (75%) had acute myeloid leukemia (AML), 7 patients (21.88%) had acute lymphoblastic leukemia (ALL) and 1 patient (3.13%) had bilineage acute leukemia (BAL). At presentation of their AL: 3 patients (9.38%) had fever, 9 patients (28.13%) had infections, 4 patients (12.5%) had palpable spleen or liver, 6 patients (18.75%) had palpable external lymph nodes, and 9 patients (28.13%) had extramedullary disease (EMD). After receiving induction and consolidation cycles of chemotherapy, 11 patients (34.38%) of AL patients received allogeneic hematopoietic stem cell transplantation (HSCT). At the end of the follow-up, 17 patients (53.1%) with AL were alive while 15 patients (46.9%) were dead. The 8-year overall survival (OS) for all patients with AL subjected to leukapheresis was 47%. The 5 years OS for patients with AL who subsequently received HSCT and those who did not receive allogeneic HSCT were 70% and 40% respectively. The mean white blood cell (WBC) count of CML patients subjected to leukapheresis was 465.5 × 109/L, 11 patients (61.11%) had clear signs of leukostasis, and 8 patients (44.44%) had splenomegaly at presentation. Regarding the disease stage at presentation, 14 CML patients (77.78%) had chronic phase (CP), 2 patients (11.11%) had accelerated phase (AP) and 2 patients (11.11%) had blast phase (BP). Regarding the fate of CML patients at the end of the study were: 15 (83.33%) were alive, 1 (5.56%) dead, and 2 (11.11%) were unknown as they lost follow-up. However, the 10-year OS of patients with CML subjected to leukapheresis was 90%. Conclusion: Patients with acute or chronic leukemia presenting with hyperleukocytosis and either ongoing or impending leukostasis should have urgent cytoreductive chemotherapy and leukapheresis to prevent life-threatening complications. Although the outcome of AL patients presenting with leukostasis is generally poor, prompt cytoreductive therapy and leukapheresis, followed by induction chemotherapy and allogeneic HSCT may improve the outcome. Also, urgent cytoreduction including leukapheresis improves the outcome of patients with CML presenting with hyperleukocytosis and leukostasis.

Inflammation is a natural response of the body to defend itself against potential threats and can be reduced through physical activity, proper nutrition, and the use of herbal medicines, which are medicinal plants. In the study, we aim to examine the anti-inflammatory effects of the volatile and ethanolic fractions of two commonly used medicinal plants, Equisetum arvense, and Baccharis trimera. The essential oils were obtained by hydrodistillation of the fresh leaves of the plants, while the ethanolic extracts were obtained using classical methodologies. All fractions were tested for anti-inflammatory activity, evaluating their ability to stabilize the red blood cell membrane and inhibit the spreading, and phagocytosis by macrophages, at concentrations varying from 200 to 600 µg mL-1. The results of the experiments suggest that the ethanolic fraction of B. trimera shows promising results compared to the positive controls. Our investigations thus contribute to the specialized literature on the use of herbal medicines around nutrition, providing guidance for future studies on these fractions.

Cells have emerged as highly promising vehicles for delivering drugs due to their unique advantages. They have the ability to bypass immune recognition, navigate biological barriers, and reach difficult-to-access tissues through sensing and active movement. Over the past couple of decades, extensive research has been conducted to understand how cell carriers can overcome biological barriers and influence drug effectiveness. This has resulted in the development of engineered cells for targeted drug delivery to specific tissues. Despite the presence of exciting developments, a comprehensive understanding of the challenges and potential strategies is necessary for the effective clinical application of cell-based drug carriers. This review provides an overview of recent progress and novel concepts in cell-based drug carriers, as well as their potential for translation into clinical practice. Additionally, we delve into important factors and emerging strategies for designing the next generation of cell-based delivery technologies, with a particular emphasis on achieving greater accuracy and targeted drug administration.

Spinal muscular atrophy is an autosomal recessive neuromuscular disorder characterized by progressive muscle weakness and atrophy. It is one of the most common single-gene disorders with an incidence rate of approximately 1 in 10,000 live births. The clinical manifestations are progressive hypotonia and muscle weakness due to the degeneration of alpha neurons in the anterior horn cells of the spinal cord and motor nuclei in the lower brain stem. Depending on the severity of the symptoms, SMA has five subtypes. Supportive measures can be offered for respiratory, gastrointestinal, and musculoskeletal complications. Carrier testing for all couples is recommended and this can be done by Multiplex Ligation-dependent Probe Amplification (MLPA). Prenatal diagnosis can be offered to carrier couples. Therapies must be given within the newborn period for maximum benefit and before the loss of motor neurons. It is achieved by identifying the SMA babies through Newborn screening. Several new FDA-approved drugs can reduce the progression of symptoms in SMA. However, they cannot offer a definite cure. Clinical follow-up and Neurological assessment demonstrate that SMA children can attain developmental milestones after receiving treatment, which is never normally attained in untreated cases. In utero SMA treatment with Zolgensma would enhance the survival rate and favorable neurological outcomes in the future. Base editing and Gene editing with CRISPR-Cas technologies to target the mutations and restore functional and stable SMN protein levels are the future hopes for a permanent cure of SMA.

Background: Bile duct injuries have been substantially increased after the introduction of laparoscopic cholecystectomy (LC). These are accompanied by major morbidity and mortality. Studies have shown varying degrees of success in the reduction of bile duct injury (BDI) using the Critical View of Safety (CVS) technique. The aim of this study was to see the efficacy of the CVS technique as the sole method of dissection in laparoscopic cholecystectomy. Methods: 1647 cases of LC were done between January 2012 and January 2022 for a period of 10 years in two hospitals. All were operated by the CVS dissection technique and none by the infundibular technique. Cases included acute cholecystitis, chronic cholecystitis, gangrenous cholecystitis, empyema, and Gallbladder (GB) polyp. Results: The average operating time was 42 minutes and the range was 13 to 80 minutes. In 92% of cases, all 3 criteria of CVS were achieved. In the remaining 8% cases were either converted to open or operated by a division of GB or subtotal cholecystectomy was done. There was only one case of cystic duct stump leak requiring drainage and common bile duct stenting.Conclusion: The excellent outcome of our study suggests that the CVS method will be the gold standard technique in the dissection of the gallbladder in LC. Further dissemination of the technique is necessary to improve safety in LC.

Essential oils (EO) are extracted from different plant species and can be present in different plant organs. Rosemary-pepper EO is composed of around 50% to 70% thymol, a phenolic compound proven to be active against fungi and bacteria. The active components present in these compounds can affect the vital functionality of bacterial cells, leading to protein denaturation and cell lysis. Therefore, the present study aims to evaluate in vitro the antibacterial potential of Lippia origanoides EO against gram-negative bacteria. This is an exploratory study, with a technical-experimental procedure, with a quantitative approach, carried out at the Federal University of Campina Grande. The strains used were Pseudomonas aeruginosa ATCC 27853, Proteus mirabilis ATCC 25933, and Escherichia coli ATCC 25922, using concentrations of 1024, 512, 256, and 128 μg/ml using the disc diffusion method in triplicate. After the incubation period, the formation of halos of bacterial growth inhibition was not observed. There are possible causes for the lack of antibacterial activity of the EO concerning the strains of gram-negative bacteria used in the study, including the possibility of not containing components with antibacterial properties in concentrations sufficient for the expected activity at the concentrations tested. Based on the results obtained, the Rosemary-Pepper EO (Lippia organoids) did not demonstrate antimicrobial activity against the gram-negative bacteria used in the study. Therefore, the development of new research with Lippia origanoides essential oil with gram-positive bacteria is suggested.