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1.
Sci Rep ; 14(1): 16744, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39033183

RESUMEN

Transformer-based models have greatly improved Land Use and Land Cover (LULC) applications. Their revolutionary ability to analyze and extract key information has greatly advanced the field. However, the high computational cost of these models presents a considerable obstacle to their practical implementation. Therefore, this study aims to strike a balance between computational cost and accuracy when employing transformer-based models for LULC analysis. We exploit transfer learning and fine-tuning strategies to optimize the resource utilization of transformer-based models. Furthermore, transparency is the core principle of our methodology to promote fairness and trust in applying LULC models across various domains, including forestry, environmental studies, and urban or rural planning. To ensure transparency, we have employed Captum, which enables us to uncover and mitigate potential biases and interpret AI-driven decisions. Our results indicate that transfer learning can potentially improve transformer-based models in satellite image classification, and strategic fine-tuning can maintain efficiency with minimal accuracy trade-offs. This research highlights the potential of Explainable AI (XAI) in Transformer-based models for achieving more efficient and transparent LULC analysis, thereby encouraging continued innovation in the field.

2.
Chem Commun (Camb) ; 60(39): 5104-5135, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38625567

RESUMEN

Water electrolysis is a promising method for efficiently producing hydrogen and oxygen, crucial for renewable energy conversion and fuel cell technologies. The hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are two key electrocatalytic reactions occurring during water splitting, necessitating the development of active, stable, and low-cost electrocatalysts. Transition metal (TM)-based electrocatalysts, spanning noble metals and TM oxides, phosphides, nitrides, carbides, borides, chalcogenides, and dichalcogenides, have garnered significant attention due to their outstanding characteristics, including high electronic conductivity, tunable valence electron configuration, high stability, and cost-effectiveness. This timely review discusses developments in TM-based electrocatalysts for the HER and OER in alkaline media in the last 10 years, revealing that the exposure of more accessible surface-active sites, specific electronic effects, and string effects are essential for the development of efficient electrocatalysts towards electrochemical water splitting application. This comprehensive review serves as a guide for designing and constructing state-of-the-art, high-performance bifunctional electrocatalysts based on TMs, particularly for applications in water splitting.

3.
ChemSusChem ; : e202400283, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38470130

RESUMEN

MXenes, a two-dimensional (2D) material, exhibit excellent optical, electrical, chemical, mechanical, and electrochemical properties. Titanium-based MXene (Ti-MXene) has been extensively studied and serves as the foundation for 2D MXenes. However, other transition metals possess the potential to offer excellent properties in various applications. This comprehensive review aims to provide an overview of the properties, challenges, key findings, and applications of less-explored vanadium-based MXenes (V-MXenes) and their composites. The current trends in V-MXene and their composites for energy storage and conversion applications have been thoroughly summarized. Overall, this review offers valuable insights, identifies potential opportunities, and provides key suggestions for future advancements in the MXenes and energy storage/conversion applications.

4.
Adv Colloid Interface Sci ; 324: 103077, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38219341

RESUMEN

Ti-MXene allows a range of possibilities to tune their compositional stoichiometry due to their electronic and electrochemical properties. Other than conventionally explored Ti-MXene, there have been ample opportunities for the non-Ti-based MXenes, especially the emerging Mo-based MXenes. Mo-MXenes are established to be remarkable with optoelectronic and electrochemical properties, tuned energy, catalysis, and sensing applications. In this timely review, we systematically discuss the various organized synthesis procedures, associated experimental tunning parameters, physiochemical properties, structural evaluation, stability challenges, key findings, and a wide range of applications of emerging Mo-MXene over Ti-MXenes. We also critically examined the precise control of Mo-MXenes to cater to advanced applications by comprehensively evaluating the summary of recent studies using artificial intelligence and machine learning tools. The critical future perspectives, significant challenges, and possible outlooks for successfully developing and using Mo-MXenes for various practical applications are highlighted.

5.
Langmuir ; 40(5): 2465-2486, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38265034

RESUMEN

Developing sustainable energy solutions to safeguard the environment is a critical ongoing demand. Electrochemical water splitting (EWS) is a green approach to create effective and long-lasting electrocatalysts for the water oxidation process. Metal organic frameworks (MOFs) have become commonly utilized materials in recent years because of their distinguishing pore architectures, metal nodes easy accessibility, large specific surface areas, shape, and adaptable function. This review outlines the most significant developments in current work on developing improved MOFs for enhancing EWS. The benefits and drawbacks of MOFs are first discussed in this review. Then, some cutting-edge methods for successfully modifying MOFs are also highlighted. Recent progress on nickel (Ni) and iron (Fe) based MOFs have been critically discussed. Finally, a comprehensive analysis of the existing challenges and prospects for Ni- and Fe-based MOFs are summarized.

6.
RSC Adv ; 13(46): 32413-32423, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37928849

RESUMEN

In response to the increasing availability of hydrogen energy and renewable energy sources, molybdenum disulfide (MoS2)-based electrocatalysts are becoming increasingly important for efficient electrochemical water splitting. This study involves the incorporation of palladium nanoparticles (PdNPs) into hydrothermally grown MoS2via a UV light assisted process to afford PdNPs@MoS2 as an alternative electrocatalyst for efficient energy storage and conversion. Various analytical techniques, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and energy dispersive spectroscopy (EDS), were used to investigate the morphology, crystal quality, and chemical composition of the samples. Although PdNPs did not alter the MoS2 morphology, oxygen evolution reaction (OER) activity was driven at considerable overpotential. When electrochemical water splitting was performed in 1.0 M KOH aqueous solution with PdNPs@MoS2 (sample-2), an overpotential of 253 mV was observed. Furthermore, OER performance was highly favorable through rapid reaction kinetics and a low Tafel slope of 59 mV dec-1, as well as high durability and stability. In accordance with the electrochemical results, sample-2 showed also a lower charge transfer resistance, which again provided evidence of OER activity. The enhanced OER activity was attributed to a number of factors, including structural, surface chemical compositions, and synergistic effects between MoS2 and PdNPs.

7.
Future Virol ; 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37970094

RESUMEN

Aim: This study aims to perform an external validation of a recently developed prognostic model for early prediction of the risk of progression to severe COVID-19. Patients & methods/materials: Patients were recruited at their initial diagnosis at two facilities within Hamad Medical Corporation in Qatar. 356 adults were included for analysis. Predictors for progression of COVID-19 were all measured at disease onset and first contact with the health system. Results: The C statistic was 83% (95% CI: 78%-87%) and the calibration plot showed that the model was well-calibrated. Conclusion: The published prognostic model for the progression of COVID-19 infection showed satisfactory discrimination and calibration and the model is easy to apply in clinical practice.d.

8.
BMC Med Educ ; 23(1): 186, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-36973738

RESUMEN

BACKGROUND: This study aims to qualitatively examine the readiness of medical students to change to virtual clerkship (VC) during the pandemic, from both the faculty and students' perspectives. METHODS: A qualitative study was conducted based on the framework of readiness to change. Focus group discussions with students, and semi-structured interviews with clinical faculty members were done using appropriate online platforms. Transcripts were then analyzed using inductive-deductive approach. RESULTS: Twelve themes emerged which are (1) Perceptions about the university's decision and its communication to students, (2) A Perceived lack of clinical experience, (3) Students' role as members of the medical team facing the pandemic, (4) Student safety, (5) Quality and design of VC and the skills it offered, (6) Belief in own ability to succeed in the VC, (7) Confidence that VC would reach its goals, (8) New enhanced learning approaches, (9) Preparing students for new types of practice in the future (10) Acquired skills, 11) Academic support and communication with faculty and college, and 12) Psychological support. Medical students showed limited readiness to undertake a virtual clerkship and not play their role as healthcare professionals during the pandemic. They perceived a huge gap in gaining clinical skills virtually and asked for a quick return to training sites. CONCLUSION: Medical students were not ready for virtual clerkships. There will be a need to integrate novel learning modalities such as patient simulations and case-based learning in order to meet future demands of the medical profession and enhance the efficiency of virtual clerkships.


Asunto(s)
COVID-19 , Prácticas Clínicas , Estudiantes de Medicina , Humanos , Estudiantes de Medicina/psicología , COVID-19/epidemiología , Pandemias , Universidades , Aprendizaje
9.
Biomed Mater Devices ; : 1-8, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36785697

RESUMEN

Artificial intelligence (AI) has the potential to make substantial progress toward the goal of making healthcare more personalized, predictive, preventative, and interactive. We believe AI will continue its present path and ultimately become a mature and effective tool for the healthcare sector. Besides this AI-based systems raise concerns regarding data security and privacy. Because health records are important and vulnerable, hackers often target them during data breaches. The absence of standard guidelines for the moral use of AI and ML in healthcare has only served to worsen the situation. There is debate about how far artificial intelligence (AI) may be utilized ethically in healthcare settings since there are no universal guidelines for its use. Therefore, maintaining the confidentiality of medical records is crucial. This study enlightens the possible drawbacks of AI in the implementation of healthcare sector and their solutions to overcome these situations.

10.
Artículo en Inglés | MEDLINE | ID: mdl-36011968

RESUMEN

Though the concept of green dynamic capability has been increasingly gaining traction among academics, practitioners, and policymakers, its association with green innovation adoption remains unclear. The present study addresses this gap and aims to provide clarity by distinguishing green innovation adoption in the context of developing countries. Drawing on dynamic capability and stakeholder theory, this research shed light on the significance of green dynamic capability for green innovation adoption. Additionally, this study examines the moderating role of environmental dynamism and big data analytics capability in the link between green dynamic capability and green innovation adoption. Adopting a two-wave research design, the sample for this study contained SMEs from Pakistan and Malaysia. Data was obtained from 220 SMEs (105 from Pakistan, 115 from Malaysia). To test the hypotheses, covariance-based structural equation modelling was performed to analyze causal relationships in the model, by using AMOS 23 software. The results showed that green dynamic capability positively impacts green innovation adoption, but environmental dynamism does not positively moderate between green dynamic capability and green innovation adoption. In addition, big data analytics capability positively moderates between green dynamic capability and green innovation adoption. We believe that this study opens a new avenue in the environmental literature under which green innovation adoption is useful for SMEs.


Asunto(s)
Macrodatos , Ciencia de los Datos , Creatividad , Organizaciones , Pakistán
11.
Fetal Pediatr Pathol ; 41(5): 749-758, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34383618

RESUMEN

BACKGROUND: Megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS) is a lethal congenital disorder characterized by a large, non-obstructed bladder, microcolon, and lack of proper peristalsis. MATERIALS AND METHODS: Five cases of MMIHS were identified, confirmed histologically and were predominantly female (F:M, 4:1). DNA sequencing was also performed. RESULTS: Four cases showed mutations in the α3 and ß4 nicotinic acetylcholine receptor (ηAChR) subunits (CHRNA3 and CHRNB4, respectively) on chromosome 15q24. The 5th case had a delayed clinical presentation of intussusception at 11 months and showed a novel missense mutation in ATP2B4 on Chromosome 1q32. CONCLUSION: The first four patients showed a previously identified mutation. The 5th patient shows a novel mutation in ATP2B4. This novel gene was associated with a less severe presentation and increases success of multiorgan transplant than the other four patients. This highlights how identifying various mutations may impact prognosis and clinical treatment plans for MMIHS patients.


Asunto(s)
Seudoobstrucción Intestinal , Receptores Nicotínicos , Anomalías Múltiples , Colon/anomalías , Femenino , Humanos , Seudoobstrucción Intestinal/genética , Masculino , Mutación , Receptores Nicotínicos/genética , Vejiga Urinaria/anomalías
12.
J Sports Med Phys Fitness ; 62(9): 1147-1152, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34256536

RESUMEN

BACKGROUND: During fielding throwing ball with more velocity and accuracy towards the stump to reduce score and produce an out of the opponent team. Core is the power house of the body. Core training improves the strength of trunk muscles and allows the players to kick, throw, pull, and push with greater force. This study was conducted to determine the effects of core muscle strengthening on throwing velocity in cricket players that whether core muscle strengthening would help the cricket players to improve their throwing velocity and core endurance. METHODS: A 6 weeks' randomized controlled trial in which Ninety-eight male cricket players participated and divided into strength training (interventional) and non-strength training (control group). Interventional group followed general core strengthening exercise protocol for six weeks for 3 days a week. Assessment of the players include core assessment test (back extension, supine forward flexion test, prone bridge test). Time and throwing velocity were noted by stop watch and radar gun in km/hr respectively at baseline and after 6 weeks of core training. Control group did not follow any exercise program but continued their usual cricket training. RESULTS: Mean age of interventional group was 20.4±4.9 years and control group was 21.6±3.4 years. The mean BMI of interventional and control group was 22.4±2.7 kg/m2 and 21.8±2.1 kg/m2, respectively. Comparing both groups, in between group analysis strength training group results showed statistically highly significant increase P<0.001 in components throwing velocity, back extension, supine flesion, right plank lateral, left lateral plane and isometric prone plank than non-strengthening group. In within group analysis, strength group had improved as compared to the control group which showed no improvement. CONCLUSIONS: There is significant increase in throwing velocity and core endurance with six weeks general core strengthening in male cricket players.


Asunto(s)
Rendimiento Atlético , Entrenamiento de Fuerza , Adolescente , Adulto , Rendimiento Atlético/fisiología , Humanos , Masculino , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Pakistán , Entrenamiento de Fuerza/métodos , Adulto Joven
13.
Fetal Pediatr Pathol ; 41(6): 909-918, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34854351

RESUMEN

Background: Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia is an inherited cardiomyopathy, characterized by replacement of the RV muscle wall with fibrofatty tissue. The diagnosis is challenging, due to the absence of a unique presentation and a lack of specific reproducible diagnostic criteria. Materials and methods: Slides and additional clinical information including follow up from 16 cases were reviewed. Pediatric criteria of >30% of muscle replacement was used, instead of >40% as used in adults. Results: All 16 cases were confirmed by genetic testing and show ARVC/D. Applying the adult criteria, 7 cases would not have been categorized as ARVC/D. Conclusion: The modified pediatric criteria for ARVC/D should be used for pediatric patients. Better detection will aid in genetic counseling in order to identify those additional family members susceptible to sudden cardiac deaths so they can be followed optimally.


Asunto(s)
Displasia Ventricular Derecha Arritmogénica , Adulto , Niño , Humanos , Displasia Ventricular Derecha Arritmogénica/diagnóstico , Displasia Ventricular Derecha Arritmogénica/genética , Pruebas Genéticas
14.
Fetal Pediatr Pathol ; 41(3): 493-498, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33164595

RESUMEN

Background: Fibroepithelial polyps of the anus have been described as mucosal hypertrophy in response to chronic irritation or tissue damage. Lesions usually remain small and mostly present in elderly adults with local disease. Case Report: An otherwise healthy 15-year-old male presented with a giant pedunculated mass projecting out of the anal verge that enlarged over 2 years, causing discomfort. Results: Upon surgical excision and histologic examination, the mass resembled a fibroepithelial polyp with numerous dilated lymphatics. Conclusions: While literature describes the spectrum of pathology possible in such lesions, often consisting of a mixture of stromal and epithelial components, dilated lymphatics are less common. This giant anal fibroepithelial polyp characterized by edematous stroma and numerous dilated lymphatics is consistent with lymphangioma. To our knowledge, this presentation is novel in this age group with no underlying risk factors.


Asunto(s)
Pólipos , Neoplasias Cutáneas , Adolescente , Adulto , Anciano , Humanos , Masculino , Pólipos/diagnóstico
15.
Fetal Pediatr Pathol ; 41(5): 759-770, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34542007

RESUMEN

BACKGROUND: CRMO is a sterile auto inflammatory bone disease that affects the pediatric population. Recently, single gene mutations in LPIN2, DIRA, and IL1RN have been reported in murine models of CRMO. MATERIALS AND METHODS: The medical records and histopathological slides of twelve patients were reviewed. RESULTS: The diagnosis was determined by multiple lesions, imaging, negative cultures, bone biopsy, and lack of antibiotic response. Biopsy showed early neutrophilic infiltrates, and older lesions showed lymphoplasmacytic infiltrates and fibrosis. Patients were treated with anti-inflammatory medication with some lesions completely resolving. CONCLUSION: Bone biopsy aids the diagnosis of CRMO in correlation with clinical presentation, imaging, and culture findings. Our findings indicate the kinetics of CRMO is not well defined and the fibrosis may be reached after months, in contrast to the previously reported several years. We hope that these genetic mutations can be further studied in human models to describe the genetics behind CRMO.


Asunto(s)
Osteomielitis , Animales , Antibacterianos/uso terapéutico , Biopsia , Niño , Enfermedad Crónica , Fibrosis , Humanos , Ratones , Osteomielitis/diagnóstico , Osteomielitis/tratamiento farmacológico , Osteomielitis/genética
16.
RSC Adv ; 13(1): 743-755, 2022 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-36683771

RESUMEN

In this study, we have prepared cobalt selenide (CoSe2) due to its useful aspects from a catalysis point of view such as abundant active sites from Se edges, and significant stability in alkaline conditions. CoSe2, however, has yet to prove its functionality, so we doped palladium oxide (PdO) onto CoSe2 nanostructures using ultraviolet (UV) light, resulting in an efficient and stable water oxidation composite. The crystal arrays, morphology, and chemical composition of the surface were studied using a variety of characterization techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR) spectroscopy. It was also demonstrated that the composite systems were heterogeneous in their morphology, undergoing a shift in their diffraction patterns, suffering from a variety of metal oxidation states and surface defects. The water oxidation was verified by a low overpotential of 260 mV at a current density of 20 mA cm-2 with a Tafel Slope value of 57 mV dec-1. The presence of multi metal oxidation states, rich surface edges of Se and favorable charge transport played a leading role towards water oxidation with a low energy demand. Furthermore, 48 h of durability is associated with the composite system. With the use of PdO and CoSe2, new, low efficiency, simple electrocatalysts for water catalysis have been developed, enabling the development of practical energy conversion and storage systems. This is an excellent alternative approach for fostering growth in the field.

17.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-21264550

RESUMEN

Two mRNA vaccines, Pfizer-BNT162b2 and Moderna-mRNA-1273, were granted the US Food and Drug Administration Emergency Use Authorization for preventing COVID-19. However, little is known about the difference in antibody responses induced by the two mRNA vaccines in naive and individuals with a previous history of infections (PI group). Therefore, we investigated the levels of anti-S-RBD total antibodies (IgM, IgA, and IgG), anti-S-RBD IgG, and anti-S-RBD IgA in these two groups 1-13 (median=6) weeks following administration of two doses of mRNA-1273 or BNT162b2 vaccines. Results showed that in naive-vaccinated group, the mRNA-1327 vaccine induces significantly higher levels of S-RBD total antibodies (3.5-fold; p<0.001), S-RBD IgG (2-fold-p<0.01), and S-IgA (2.1-fold, p<0.001) than the BNT162b2 vaccine. In the PI-vaccinated group, both vaccines produce significantly higher S-RBD total antibodies level than those of the naive-vaccinated group. The PI group produced a higher level of S-RBD IgG than the naive-BNT162b2 (p=0.05) but not more than the naive-mRNA-1273 (p=0.9) group. Interestingly, the PI-vaccinated group produced a comparable level of IgA ratio to the naive-mRNA-1273 group but significantly higher than the naive-BNT162b2 group (1.6-fold, p<0.001). Our results showed that the mRNA-1327 vaccine is more immunogenic and induces a greater antibody response than the BNT162b2 vaccine.

18.
J Glob Health ; 11: 05005, 2021 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-33643638

RESUMEN

BACKGROUND: Mathematical modeling constitutes an important tool for planning robust responses to epidemics. This study was conducted to guide the Qatari national response to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemic. The study investigated the epidemic's time-course, forecasted health care needs, predicted the impact of social and physical distancing restrictions, and rationalized and justified easing of restrictions. METHODS: An age-structured deterministic model was constructed to describe SARS-CoV-2 transmission dynamics and disease progression throughout the population. RESULTS: The enforced social and physical distancing interventions flattened the epidemic curve, reducing the peaks for incidence, prevalence, acute-care hospitalization, and intensive care unit (ICU) hospitalizations by 87%, 86%, 76%, and 78%, respectively. The daily number of new infections was predicted to peak at 12 750 on May 23, and active-infection prevalence was predicted to peak at 3.2% on May 25. Daily acute-care and ICU-care hospital admissions and occupancy were forecast accurately and precisely. By October 15, 2020, the basic reproduction number R0 had varied between 1.07-2.78, and 50.8% of the population were estimated to have been infected (1.43 million infections). The proportion of actual infections diagnosed was estimated at 11.6%. Applying the concept of Rt tuning, gradual easing of restrictions was rationalized and justified to start on June 15, 2020, when Rt declined to 0.7, to buffer the increased interpersonal contact with easing of restrictions and to minimize the risk of a second wave. No second wave has materialized as of October 15, 2020, five months after the epidemic peak. CONCLUSIONS: Use of modeling and forecasting to guide the national response proved to be a successful strategy, reducing the toll of the epidemic to a manageable level for the health care system.


Asunto(s)
COVID-19/epidemiología , COVID-19/prevención & control , Epidemias/prevención & control , Modelos Teóricos , COVID-19/terapia , Predicción , Hospitalización/estadística & datos numéricos , Humanos , Incidencia , Unidades de Cuidados Intensivos/estadística & datos numéricos , Prevalencia , Qatar/epidemiología
19.
Fetal Pediatr Pathol ; 40(6): 691-696, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32156178

RESUMEN

Background Right ventricular myocardial fatty infiltration has been observed in pediatric cardiac allografts with an associated decrease in graft life expectancy. A possible explanation included an immunosuppressant drug effect which prompted us to examine common factors between non-cardiac transplanted immunosuppressed patients and postmortem hearts of pediatric patients who died of non-cardiac causes.Materials and Methods Sixty-one of 1,030 pediatric autopsies were from immunosuppressed children who were treated with corticosteroids for malignant tumors, non-cardiac transplantations, or other chronic clinical conditions. 62 children who died for non-medical reasons served as controls. Cardiac H&E autopsy slides were examined for right ventricular fatty infiltration.Results There was a significant increase in right ventricular fatty infiltration in patients that were non-cardiac transplanted and immunosuppressed compared to controls. None of the index patients had other features of arrhythmogenic right ventricular dysplasia.Conclusions Immunosuppression may lead to right ventricular fatty infiltration in childhood.


Asunto(s)
Displasia Ventricular Derecha Arritmogénica , Ventrículos Cardíacos , Autopsia , Niño , Humanos , Inmunosupresores/efectos adversos , Miocardio
20.
Cureus ; 12(8): e9802, 2020 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-32953314

RESUMEN

Streptococcus constellatus is a member of Streptococcus milleri group which is a subgroup of Viridans streptococci, first described by Guthof in 1956 after being isolated from dental abscesses. S. constellatus, a gram positive, non-sporing, non-motile, catalase negative cocci, is the normal flora of the oropharyngeal, gastrointestinal and urogenital tract. It is not a commonly encountered pathogen but has a propensity to form abscesses and cause bacteremia in the immunocompromised patient. Here, we report a 78-year-old man with sepsis due to Streptococcus constellatus liver abscess. The patient had a history of hypertension, stroke, benign prostatic hyperplasia, vascular dementia and myocardial infarction status post coronary artery bypass grafting. There has been no particular link between any of these conditions to S. constellatus. However, immunocompromised status predisposes to fulminant infection and formation of abscesses. The patient was febrile with a temperature of 99.1°F, blood pressure of 143/73 mmHg and the heart rate (HR) of 98. Labs revealed a leukocytosis of 16.90 K/uL, hemoglobin 11.8 g/dL, hematocrit 35.8%, total bilirubin 1.7 mg/dL, direct bilirubin 1.0 mg/dL, aspartate aminotransferase (AST) 44 IU/L, alanine aminotransferase (ALT) 28 IU/L, alkaline phosphatase (ALKP) 176 IU/L and lactate dehydrogenase (LDH) was 290 IU/L. He was started on intravenous Maxipime and Unasyn which was switched to Rocephin and Clindamycin based on the Infectious disease recommendations. Metronidazole was also started and the serologies were sent for Entamoeba histolytica. Computerized tomography (CT) scan showed an abscess in the right lobe of the liver which was finally drained using an interventional radiology (IR)-guided approach. The cultures from the fluid and blood yielded S. constellatus and thus Metronidazole was discontinued. The patient improved after a few days and the drainage catheter was pulled out and the patient discharged in stable condition.

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