Assessment of Cardiac, Vascular, and Pulmonary Pathobiology In Vivo During Acute COVID-19.

Background Acute COVID-19-related myocardial, pulmonary, and vascular pathology and how these relate to each other remain unclear. To our knowledge, no studies have used complementary imaging techniques, including molecular imaging, to elucidate this. We used multimodality imaging and biochemical sampling in vivo to identify the pathobiology of acute COVID-19. Specifically, we investigated the presence of myocardial inflammation and its association with coronary artery disease, systemic vasculitis, and pneumonitis. Methods and Results Consecutive patients presenting with acute COVID-19 were prospectively recruited during hospital admission in this cross-sectional study. Imaging involved computed tomography coronary angiography (identified coronary disease), cardiac 2-deoxy-2-[fluorine-18]fluoro-D-glucose positron emission tomography/computed tomography (identified vascular, cardiac, and pulmonary inflammatory cell infiltration), and cardiac magnetic resonance (identified myocardial disease) alongside biomarker sampling. Of 33 patients (median age 51 years, 94% men), 24 (73%) had respiratory symptoms, with the remainder having nonspecific viral symptoms. A total of 9 patients (35%, n=9/25) had cardiac magnetic resonance-defined myocarditis. Of these patients, 53% (n=5/8) had myocardial inflammatory cell infiltration. A total of 2 patients (5%) had elevated troponin levels. Cardiac troponin concentrations were not significantly higher in patients with and without myocarditis (8.4 ng/L [interquartile range, IQR: 4.0-55.3] versus 3.5 ng/L [IQR: 2.5-5.5]; P=0.07) or myocardial cell infiltration (4.4 ng/L [IQR: 3.4-8.3] versus 3.5 ng/L [IQR: 2.8-7.2]; P=0.89). No patients had obstructive coronary artery disease or vasculitis. Pulmonary inflammation and consolidation (percentage of total lung volume) was 17% (IQR: 5%-31%) and 11% (IQR: 7%-18%), respectively. Neither were associated with the presence of myocarditis. Conclusions Myocarditis was present in a third patients with acute COVID-19, and the majority had inflammatory cell infiltration. Pneumonitis was ubiquitous, but this inflammation was not associated with myocarditis. The mechanism of cardiac pathology is nonischemic and not attributable to a vasculitic process. Registration URL: https://www.isrctn.com; Unique identifier: ISRCTN12154994.

A prospective observational study of community acquired pneumonia in Kenya: the role of viral pathogens.

BACKGROUND: Lower respiratory tract infections continue to contribute significantly to morbidity and mortality across all age groups globally. In sub-Saharan Africa, many studies of community acquired pneumonia in adults have focused on HIV-infected patients and little attention has been given to risk factors and etiologic agents in an urban area with a more moderate HIV prevalence. METHODS: We prospectively enrolled 77 patients admitted to a 280 bed teaching hospital in Kenya with radiographically confirmed community acquired pneumonia from May 2019 to March 2020. The patients were followed for etiology and clinical outcomes. Viral PCR testing was performed using the FTD respiratory pathogen-21 multiplex kit on nasopharyngeal or lower respiratory samples. Additional microbiologic workup was performed as determined by the treating physicians. RESULTS: A potential etiologic agent(s) was identified in 57% including 43% viral, 5% combined viral and bacterial, 5% bacterial and 4% Pneumocystis. The most common etiologic agent was Influenza A which was associated with severe clinical disease. The most common underlying conditions were cardiovascular disease, diabetes and lung disease, while HIV infection was identified in only 13% of patients. Critical care admission was required for 24, and 31% had acute kidney injury, sometimes in combination with acute respiratory distress or sepsis. CONCLUSION: Viruses, especially influenza, were commonly found in patients with CAP. In contrast to other studies from sub-Saharan Africa, the underlying conditions were similar to those reported in high resource areas and point to the growing concern of the double burden of infectious and noncommunicable diseases.

CardiOvaScular Mechanisms In Covid-19: methodology of a prospective observational multimodality imaging study (COSMIC-19 study).

BACKGROUND: 8-28% of patients infected with COVID-19 have evidence of cardiac injury, and this is associated with an adverse prognosis. The cardiovascular mechanisms of injury are poorly understood and speculative. We aim to use multimodality cardiac imaging including cardiac magnetic resonance (CMR) imaging, computed tomography coronary angiography (CTCA) and positron emission tomography with 2-deoxy-2-[fluorine-18]fluoro-D-glucose integrated with computed tomography (18F-FDG-PET/CT) to identify the cardiac pathophysiological mechanisms related to COVID-19 infections. METHODS: This is a single-centre exploratory observational study aiming to recruit 50 patients with COVID-19 infection who will undergo cardiac biomarker sampling. Of these, 30 patients will undergo combined CTCA and 18F-FDG-PET/CT, followed by CMR. Prevalence of obstructive and non-obstructive atherosclerotic coronary disease will be assessed using CTCA. CMR will be used to identify and characterise myocardial disease including presence of cardiac dysfunction, myocardial fibrosis, myocardial oedema and myocardial infarction. 18F-FDG-PET/CT will identify vascular and cardiac inflammation. Primary endpoint will be the presence of cardiovascular pathology and the association with troponin levels. DISCUSSION: The results of the study will identify the presence and modality of cardiac injury associated COVID-19 infection, and the utility of multi-modality imaging in diagnosing such injury. This will further inform clinical decision making during the pandemic. TRIAL REGISTRATION: This study has been retrospectively registered at the ISRCTN registry (ID ISRCTN12154994) on 14th August 2020. Accessible at https://www.isrctn.com/ISRCTN12154994.

Unusual presentation of hepatocellular carcinoma: Case report and review of literature.

Hepatocellular carcinoma (HCC) is the most common primary cancer of the liver and a major cause of mortality globally. Atypical presentation of HCC can present a diagnostic challenge. We, therefore, present a rare case of hepatocellular carcinoma fungating through the anterior abdominal wall with concomitant lung and brain metastases in a young patient with non-cirrhotic liver but positive chronic hepatitis B serology.

Optimal method for metabolic tumour volume assessment of cervical cancers with inter-observer agreement on [18F]-fluoro-deoxy-glucose positron emission tomography with computed tomography.

PURPOSE: Cervical cancer metabolic tumour volume (MTV) derived from [18F]-FDG PET/CT has a role in prognostication and therapy planning. There is no standard method of outlining MTV on [18F]-FDG PET/CT. The aim of this study was to assess the optimal method to outline primary cervical tumours on [18F]-FDG PET/CT using MRI-derived tumour volumes as the reference standard. METHODS: 81 consecutive cervical cancer patients with pre-treatment staging MRI and [18F]-FDG PET/CT imaging were included. MRI volumes were compared with different PET segmentation methods. Method 1 measured MTVs at different SUVmax thresholds ranging from 20 to 60% (MTV20-MTV60) with bladder masking and manual adjustment when required. Method 2 created an isocontour around the tumour prior to different SUVmax thresholds being applied. Method 3 used an automated gradient method. Inter-observer agreement of MTV, following manual adjustment when required, was recorded. RESULTS: For method 1, the MTV25 and MTV30 were closest to the MRI volumes for both readers (mean percentage change from MRI volume of 2.9% and 13.4% for MTV25 and - 13.1% and - 2.0% for MTV30 for readers 1 and 2). 70% of lesions required manual adjustment at MTV25 compared with 45% at MTV30. There was excellent inter-observer agreement between MTV30 to MTV60 (ICC ranged from 0.898-0.976 with narrow 95% confidence intervals (CIs)) and moderate agreement at lower thresholds (ICC estimates of 0.534 and 0.617, respectively for the MTV20 and MTV25 with wide 95% CIs). Bladder masking was performed in 86% of cases overall. For method 2, excellent correlation was demonstrated at MTV25 and MTV30 (mean % change from MRI volume of -3.9% and - 8.6% for MTV25 and - 16.9% and 19% for MTV30 for readers 1 and 2, respectively). This method also demonstrated excellent ICC across all thresholds with no manual adjustment. Method 3 demonstrated excellent ICC of 0.96 (95% CI 0.94-0.97) but had a mean percentage difference from the MRI volume of - 19.1 and - 18.2% for readers 1 and 2, respectively. 21% required manual adjustment for both readers. CONCLUSION: MTV30 provides the optimal correlation with MRI volume taking into consideration the excellent inter-reader agreement and less requirement for manual adjustment.

Spectrum of imaging findings in AIDS-related diffuse large B cell lymphoma.

Lymphoma in HIV-infected patients is AIDS defining. This is the second most common AIDS defining malignancy after Kaposi's sarcoma. Development of lymphoma in HIV patients is related to immunosuppression and high viral load. Co-infection with other lymphotrophic viruses especially EBV is also strongly associated with development of lymphoma in HIV patients. Despite advances in HAART therapy, incidence of diffuse large B cell lymphoma in HIV-infected patients remains significantly higher than in the general population.Early diagnosis is challenging due to presence of opportunistic infections and atypical presentation of the lymphoma in this subset of patients. Atypical imaging findings are not unusual, and the diagnosis of lymphoma on imaging is on many occasions unexpected as the patient would ideally be initially investigated for presumed opportunistic infection.Lymphoma treatment approaches in HIV patients are complicated by comorbidity with opportunistic infections and performance status of the patients. Treatment failure and early relapse are also common in AIDS-related lymphoma. This review article highlights the common and unusual multimodality imaging findings in HIV-associated lymphoma.

Urinary bladder metastasis from breast cancer: a rare cause of hematuria.

Breast cancer is the most common cancer in women globally as well as in Kenya. The most common sites of metastases reported include the bones, liver and lung. Metastasis to the urinary bladder is relatively uncommon with only a few case reports in literature. It can therefore be easily overlooked as a cause of hematuria in these patients. We describe a rare case of a patient with breast cancer who presented with urinary bladder metastasis as a late complication of her illness.

Bone scintigraphy imaging of cardiac amyloidosis.

Transthyretin-related cardiac amyloidosis (ATTR) amyloidosis is an aggressive, rapidly progressive, and fatal disease, for which several promising therapies are in development. This condition is frequently underdiagnosed because of the limited specificity of echocardiography and the traditional requirement for histological diagnosis. It is well known that 99mtechnetium-labeled bone scan radiotracers can localize in the myocardial amyloid deposits, but the use of this imaging modality to differentiate between the two subtypes has only lately been revisited. We report a case of a 76-year-old man with a clinical diagnosis of amyloidosis who underwent a bone scan that had features of ATTR amyloidosis. To the best of our knowledge, this is the first case report in Sub-Saharan Africa.

Aspirin Reduces Cardiac Interstitial Fibrosis by Inhibiting Erk1/2-Serpine2 and P-Akt Signalling Pathways.

BACKGROUND/AIMS: Cardiac interstitial fibrosis is an abnormality of various cardiovascular diseases, including myocardial infarction, hypertrophy, and atrial fibrillation, and it can ultimately lead to heart failure. However, there is a lack of practical therapeutic approaches to treat fibrosis and reverse the damage to the heart. The purpose of this study was to investigate the effect of long-term aspirin administration on pressure overload-induced cardiac fibrosis in mice and reveal the underlying mechanisms of aspirin treatment. METHODS: C57BL/6 mice were subjected to transverse aortic constriction (TAC), and treated with 10 mg·kg-1·day-1 of aspirin for 4 weeks. Masson staining and a collagen content assay were used to detect the effects of aspirin on cardiac fibrosis in vivo and in vitro. Western blot and qRT-PCR were applied to examine the impact of aspirin on extracellular signal-regulated kinases (Erks), p-Akt/ß-catenin, SerpinE2, collagen I, and collagen III levels in the mice heart. RESULTS: Aspirin significantly suppressed the expression of α-smooth muscle actin (α-SMA; 1.19±0.19-fold) and collagen I (0.95±0.09-fold) in TAC mice. Aspirin, at doses of 100 and 1000 µM, also significantly suppressed angiotensin II-induced α-SMA and collagen I in cultured CFs. The enhanced phosphorylation of Erk1/2 caused by TAC (p-Erk1, 1.49±0.19-fold; p-Erk2, 1.96±0.68-fold) was suppressed by aspirin (p-Erk1, 1.04±0.15-fold; p-Erk2, 0.87±0.06-fold). SerpinE2 levels were suppressed via the Erk1/2 signalling pathway following treatment with aspirin (1.36±0.12-fold for TAC; 1.06±0.07-fold for aspirin+TAC). The p-Akt and ß-catenin levels were also significantly inhibited in vivo and in vitro. CONCLUSIONS: Our study reveals a novel mechanism by which aspirin alleviates pressure overload-induced cardiac interstitial fibrosis in TAC mice by suppressing the p-Erk1/2 and p-Akt/ß-catenin signalling pathways.

Cervical cancer with bilateral ovarian metastases: case report and review of literature.

Cervical cancers only rarely metastasize to the ovaries. Most of the reported cases are in Western and Asian literature and to the best of our knowledge, this is the first case report of cervical cancer presenting with bilateral ovarian metastasis in sub-Saharan Africa. We present a case report of a 44-year-old female with an 8-month history of irregular per vaginal bleeding. Imaging showed ill-defined masses in the cervix and both adnexae. After biopsy, a diagnosis of cervical squamous cell carcinoma with bilateral ovarian metastases was made.

Overexpression of SerpinE2/protease nexin-1 Contribute to Pathological Cardiac Fibrosis via increasing Collagen Deposition.

Although increases in cardiovascular load (pressure overload) are known to elicit ventricular remodeling including cardiomyocyte hypertrophy and interstitial fibrosis, the molecular mechanisms of pressure overload or AngII -induced cardiac interstitial fibrosis remain elusive. In this study, serpinE2/protease nexin-1 was over-expressed in a cardiac fibrosis model induced by pressure-overloaded via transverse aortic constriction (TAC) in mouse. Knockdown of serpinE2 attenuates cardiac fibrosis in a mouse model of TAC. At meantime, the results showed that serpinE2 significantly were increased with collagen accumulations induced by AngII or TGF-ß stimulation in vitro. Intriguingly, extracellular collagen in myocardial fibroblast was reduced by knockdown of serpinE2 compared with the control in vitro. In stark contrast, the addition of exogenous PN-1 up-regulated the content of collagen in myocardial fibroblast. The MEK1/2- ERK1/2 signaling probably promoted the expression of serpinE2 via transcription factors Elk1 in myocardial fibroblast. In conclusion, stress-induced the ERK1/2 signaling pathway activation up-regulated serpinE2 expression, consequently led accumulation of collagen protein, and contributed to cardiac fibrosis.

High Prevalence of Liver Fibrosis in Patients with Human Immunodeficiency Virus Monoinfection and Human Immunodeficiency Virus Hepatitis-B Co-infection as Assessed by Shear Wave Elastography: Study at a Teaching Hospital in Kenya.

OBJECTIVES: The aim of this study was to determine the prevalence of liver fibrosis in patients with human immunodeficiency virus (HIV) monoinfection versus those with HIV hepatitis-B virus (HBV) co-infection as assessed with shear wave elastography (SWE) in a tertiary sub-Saharan Africa hospital. MATERIALS AND METHODS: A total of 105 consecutive patients, 70 with HIV monoinfection and 35 with HIV-HBV co-infection, had liver elastography obtained using SWE to assess for the presence of liver fibrosis the cutoff of which was 5.6 kPa. Assessment of aspartate aminotransferase-to-platelet ratio index (APRI) score (a noninvasive serum biomarker of liver fibrosis) in these patients was also done. RESULTS: The prevalence of liver fibrosis was significantly higher (P < 0.0001) in patients with HIV-HBV co-infection, 25.7%, compared to those with HIV monoinfection, 7.1%. APRI score was greater in patients with HIV-HBV co-infection than those with HIV monoinfection. HIV co-infection with HBV accelerates progression to liver fibrosis. Association of a low cluster of differentiation 4 (CD-4) count with advanced fibrosis supports earlier starting of antiretroviral therapy to prevent rapid progression of liver disease in HIV-positive patients. CONCLUSION: In view of the high prevalence of liver fibrosis in patients with HIV-HBV co-infection, regular monitoring of the disease progression is recommended.

Acetyl salicylic acid attenuates cardiac hypertrophy through Wnt signaling.

Ventricular hypertrophy is a powerful and independent predictor of cardiovascular morbid events. The vascular properties of low-dose acetyl salicylic acid (aspirin) provide cardiovascular benefits through the irreversible inhibition of platelet cyclooxygenase 1; however, the possible anti-hypertrophic properties and potential mechanism of aspirin have not been investigated in detail. In this study, healthy wild-type male mice were randomly divided into three groups and subjected to transverse aortic constriction (TAC) or sham operation. The TAC-operated mice were treated with the human equivalent of low-dose aspirin (10 mg·kg(-1)·d(-1)); the remaining mice received an equal amount of phosphate buffered saline with 0.65% ethanol, which was used as a vehicle. A cardiomyocyte hypertrophy model induced by angiotensin II (10 nmol·L(-1)) was treated with the human equivalent of low (10 or 100 µmol·L(-1)) and high (1000 µmol·L(-1)) aspirin concentrations in plasma. Changes in the cardiac structure and function were assessed through echocardiography and transmission electron microscopy. Gene expression was determined through RT-PCR and western blot analysis. Results indicated that aspirin treatment abrogated the increased thickness of the left ventricular anterior and posterior walls, the swelling of mitochondria, and the increased surface area in in vivo and in vitro hypertrophy models. Aspirin also normalized the upregulated hypertrophic biomarkers, ß-myosin heavy chain (ß-MHC), atrial natriuretic peptide (ANP), and b-type natriuretic peptide (BNP). Aspirin efficiently reversed the upregulation of ß-catenin and P-Akt expression and the TAC- or ANG II-induced downregulation of GSK-3ß. Therefore, low-dose aspirin possesses significant anti-hypertrophic properties at clinically relevant concentrations for anti-thrombotic therapy. The downregulation of ß-catenin and Akt may be the underlying signaling mechanism of the effects of aspirin.

miR-101 promotes breast cancer cell apoptosis by targeting Janus kinase 2.

AIMS: microRNA-101 (miR-101) is down-regulated in several cancers. In this study, we explored the effects of dysregulated miR-101 on breast cancer cells and the underlying mechanisms. METHODS: miR-101 level was quantified by real-time RT-PCR. Cell viability was analyzed by MTT assay. Apoptosis was detected by flow cytometry and TUNEL assay. Moreover, the level of protein expression was determined by Western blot. RESULTS: miR-101 level was markedly reduced in both the human breast cancer samples and cultured breast cancer cell lines (MCF-7, MDA-MB-231). Overexpression of miR-101 inhibited the proliferation and promoted the apoptosis in cultured MCF-7 and MDA-MB-231 cells, which were reversed by co-transfection of AMO-101, the inhibitor of miR-101. We validated Janus kinase 2 (Jak2) as a direct target of miR-101. Knockdown of Jak2 induced apoptosis in cultured breast cancer cells. Moreover, the level of miR-101 is negatively correlated with Jak2 in breast cancer tissues and cell lines. CONCLUSIONS: miR-101 suppressed proliferation and promoted apoptosis in breast cancer cells by targeting Jak2. These findings indicate that manipulation of miR-101 expression may represent a novel therapeutic strategy in the treatment of breast cancer.

Cisapride protects against cardiac hypertrophy via inhibiting the up-regulation of calcineurin and NFATc-3.

Cisapride has been shown to have electrophysiological effects on the heart. The aim of this study was to investigate whether cisapride has effects on cardiac hypertrophy. Rat and cellular models of cardiac hypertrophy were used in this study. Cell surface area (CSA), mRNA and protein expression were used to evaluate cardiac hypertrophy. Cardiac function was measured by echocardiography. Cisapride attenuated ISO-induced increase in CSA in a dose-dependent manner in cultured neonatal rat cardiomyocytes. A significant anti-hypertrophic effect was achieved by cisapride 0.01µM (P<0.05). Cisapride repressed the increased mRNA levels of ANP, BNP, ß-MHC in ISO-treated cells (P<0.05). However, mallotoxin or GR113808 did not influence anti-hypertrophic effects of cisapride. In addition, cisapride inhibited the increase of intracellular Ca(2+) ([Ca(2+)]i) and the upregulation of protein levels of calcineurin and NFATc-3 (P<0.05) as well as prevented the downregulation of p-NFATc-3 (P<0.01) induced by ISO. Consistently, cisapride (0.5mg/kg/day) produced inhibitory effects on cardiac hypertrophy, including the suppression of ANP, BNP, ß-MHC, calcineurin, and NFATc-3; elevation of p-NFATc-3; reduction of cross-sectional area of cardiomyocytes in rat heart; and restoration of cardiac dysfunction by improving left ventricular diastolic and systolic performance. Importantly, cisapride 0.5 and 5.0mg/kg/day did not cause prolongation of QT and QTc intervals in rats. In conclusion, cisapride possesses a prominent anti-hypertrophic property which is likely to be conferred by its ability to downregulate Ca(2+)/calcineurin/NFAT and the present data provide new insight into this drug action.

The antifibrotic effects and mechanisms of microRNA-26a action in idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and high-lethality fibrotic lung disease characterized by excessive fibroblast proliferation, extracellular matrix accumulation, and, ultimately, loss of lung function. Although dysregulation of some microRNAs (miRs) has been shown to play important roles in the pathophysiological processes of IPF, the role of miRs in fibrotic lung diseases is not well understood. In this study, we found downregulation of miR-26a in the lungs of mice with experimental pulmonary fibrosis and in IPF, which resulted in posttranscriptional derepression of connective tissue growth factor (CTGF), and induced collagen production. More importantly, inhibition of miR-26a in the lungs caused pulmonary fibrosis in vivo, whereas overexpression of miR-26a repressed transforming growth factor (TGF)-ß1-induced fibrogenesis in MRC-5 cells and attenuated experimental pulmonary fibrosis in mice. Our study showed that miR-26a was downregulated by TGF-ß1-mediated phosphorylation of Smad3. Moreover, miR-26a inhibited the nuclear translocation of p-Smad3 through directly targeting Smad4, which determines the nuclear translocation of p-Smad2/Smad3. Taken together, our experiments demonstrated the antifibrotic effects of miR-26a in fibrotic lung diseases and suggested a new strategy for the prevention and treatment of IPF using miR-26a. The current study also uncovered a novel positive feedback loop between miR-26a and p-Smad3, which is involved in pulmonary fibrosis.