Development of a novel angiotensin converting enzyme 2 stimulator with broad implications in SARS-CoV2 and type 1 diabetes

Angiotensin-converting enzyme 2 (ACE2) is protective in cardiovascular disease, lung injury and diabetes yet paradoxically underlies our susceptibility to SARs-CoV2 infection and the fatal heart and lung disease it can induce. Furthermore, diabetic patients have chronic, systemic inflammation and altered ACE2 expression resulting in increased risk of severe COVID-19 and the associated mortality. A drug that could increase ACE2 activity and inhibit cellular uptake of severe acute respiratory syndrome coronavirus 2 (SARs-CoV2), thus decrease infection, would be of high relevance to cardiovascular disease, diabetes and SARs-CoV2 infection. While the need for such a drug lead was highlighted over a decade ago receiving over 600 citations,1 to date, no such drugs are available.2 Here, we report the development of a novel ACE2 stimulator, designated '2A'(international PCT filed), which is a 10 amino acid peptide derived from a snake venom, and demonstrate its in vitro and in vivo efficacy against SARs-CoV2 infection and associated lung inflammation. Peptide 2A also provides remarkable protection against glycaemic dysregulation, weight loss and disease severity in a mouse model of type 1 diabetes. No untoward effects of 2A were observed in these pre-clinical models suggesting its strong clinical translation potential.

YY-11, a camel milk-derived peptide, inhibits TGF-β-mediated atherogenic signaling in human vascular smooth muscle cells

Atherosclerosis, the major underlying pathology of cardiovascular disease, commences with the binding and trapping of lipids on modified proteoglycans, with hyperelongated glycosaminoglycan chains. Transforming growth factor (TGF)-β stimulates glycosaminoglycan elongation in vascular smooth muscle cells. We have recently shown that this TGF-β signaling pathway involves reactive oxygen species (ROS). YY-11 is a dodecapeptide derived from camel milk and it has antioxidant activity. We have investigated the role of YY-11 in blocking ROS signaling and downstream atherogenic responses. YY-11 inhibited TGF-β stimulated ROS production and inhibited the expression of genes for glycosaminoglycan chain elongation as a component of an in vitro model of atherosclerosis. This study provides a biochemical mechanism for the role of camel milk as a potential nutritional product to contribute to the worldwide amelioration of cardiovascular disease. PRACTICAL APPLICATIONS: The identification of readily accessible foods with antioxidant properties would provide a convenient and cost-effective approach community wide reducing oxidative stress induced pathologies such as atherosclerosis. We demonstrate that camel milk-derived peptide is an antioxidant that can inhibit growth factor-mediated proteoglycan modification in vitro. As proteoglycan modification is being recognized as one of the earliest atherogenic responses, these data support the notion of camel milk as a suitable nutritional product to contribute to the prevention of early stage of atherosclerosis development.

Diffusion-weighted imaging in gynaecological malignancy

Diffusion weighted imaging (DWI) has become an essential part of the gynaecological magnetic resonance imaging (MRI) protocol. DWI is used as an adjunct to conventional MRI sequences and has been shown to improve reporting accuracy in the imaging of gynaecological malignancy. In this review, we discuss the role of DWI in the diagnosis, staging, and assessment of treatment response of endometrial, cervical, and ovarian cancer. We also review the role of DWI in the assessment of the sonographically indeterminate ovarian lesion. Further, we highlight potential pitfalls that can beset the accurate interpretation of DWI in patients with gynaecological malignancy.

Henneguya sp. in yellowfin goby Acanthogobius flavimanus from the San Francisco Estuary

Myxozoan spores were observed in yellowfin goby Acanthogobius flavimanus collected from Suisun Marsh, San Francisco Estuary (SFE). Although histopathological changes associated with the parasite were not observed, the spores formed plasmodia that partially blocked the gastric and intestinal mucosa and gut lumen and may affect the perfomance and survival of the yellowfin goby. Morphological features of the spores resembled Henneguya sp. and molecular analysis of the 18S ribosomal DNA (Domain III) confirmed close similarity to H. rhinogobii and H. pseudorhinogobii isolated from the Japanese freshwater goby. The yellowfin goby myxozoan however, is likely an undescribed species based on phylogenetic analysis and morphologic features. Detailed description of vegetative and spore stages are currently lacking for proposal to a new species of Henneguya. A specific PCR test was developed, which confirmed a 100% prevalence of the parasite among randomly collected gobies in group 1 (N = 30) and group 2 (N = 15) at termination of the study at one month in captivity. The myxozoan was also detected from 18 gobies (12%) that died in the first group within two weeks in captivity. Apparently healthy gobies that served as controls did not reveal the presence of the myxozoan by PCR. This study documents the occurrence of a potentially new species of myxozoan in the yellowfin goby and underscores the detection of a parasitic infection in an introduced fish in the SFE. Although the pathogenesis of the myxozoan was not assessed and the prevalence as reported here is restricted to a comparatively small collection site in Suisun slough, the reemergence, identification, and ecological relevance of the parasite on goby populations in the SFE may be investigated in the future using the specific diagnostic tool developed in this study.

Incidental breast lesions detected on CT: what is their significance?

An increasing number of breast lesions are being detected incidentally on CT. The aim of this study was to investigate the rate of referrals to the breast unit for assessment of lesions identified on CT and the resulting yield of previously undiagnosed breast malignancies from this pathway. A retrospective review was undertaken of CT examinations conducted over a period of 14 years. All patients (with no previous history of breast cancer) whose report contained the keyword "breast" and who were referred to a specialist breast unit for assessment were reviewed. CT lesion morphology and enhancement pattern were identified and compared with the final diagnostic outcome. 70 patients were identified by retrospective analysis, yielding 78 incidental breast lesions, of which 22 (28.2%) were malignant (category B5). This gave a positive predictive value (PPV) for malignancy of 28.2%. The best morphological predictor of malignancy was spiculation (PPV, 76%) and irregularity (PPV, 58%), whereas calcification patterns (PPV, 36%) were diagnostically unhelpful. Malignant lesions were likely to be larger (mean, 28.5 mm) than benign lesions (mean, 20.2 mm; p<0.05). In conclusion, 30% of incidental breast lesions in this large series of patients proved to be unsuspected breast cancers, particularly irregular spiculated masses. Referral for formal triple assessment of CT-diagnosed breast lesions is worthwhile, and careful examination of the breast should be a routine part of CT examinations.

RECIST and Choi criteria for response assessment (RA) in patients with inoperable and metastatic gastrointestinal stromal tumours (GISTs) on imatinib mesylate. Cambridge GIST study group experience

10019

Background: Imatinib Mesylate (IM) induces an overall response rate of 84% in patients (pts) with metastatic GISTs. Standard RA is by RECIST criteria. This may underestimate the true benefit of IM in such pts. Choi et al observed ↓ in size (10%) and or density (D) (15%) correlated well with disease specific survival. We report our experience using both RECIST and Choi criteria for RA in GIST pts on IM. Methods: Between 2003 and 06, 24 pts with metastatic or inoperable GISTs were treated with IM. 50 lesions (Liver 20, Omentum 21, Primary 9) were identified at presentation on contrast CT (Siemens multi slice CT, IV Niopam, GE PACS system). 3 monthly CT was used for RA until tumour progression (PD) or death. Parameters recorded were: 1.Largest dimension 2. Lesion density (Mean Hounsfield units, HFU) 3.New lesions 4.Any new features. RECIST and Choi criteria were both applied for RA. Results: N=50. At 3 months (m) only 16% of the lesions achieved partial response (PR) by RECIST and 24% increased in size by a mean of 22.5% (Range 3–150%). RA as measured by Choi criteria revealed 88% of lesions had either a 10% ↓ in size or a 15% ↓ in D at 3 m. Mean ↓ in D was 29% (95% CI 24.6–33.4). At 18 m 50% of the lesions achieved PR and 20% had PD by RECIST criteria, and with Choi criteria 68% RR was recorded. Calcification, haemorrhage and perforation within the lesions spuriously altered the mean D value in 15% of the lesions which made assessment by Choi criteria difficult. In 5 pts new hepatic cystic lesions (range 2–22) appeared with a mean D of 16 HF. None were detected in extra-hepatic sites. 4 pts showed new calcifications within lesions 3–18 m on IM. Enhancing nodules within lesions were seen in 4 pts predating clinical PD by 6–18 m. Conclusions: Choi criteria were found to be reproducible in our pts. RRs at 3 months using Choi criteria (88%) were far greater than by RECIST criteria (16%). RRs were more similar at 18 m (68% Choi vs 50% RECIST).Using density for RA can become unreliable in the presence of perforation, calcification and haemorrhage. These criteria should be evaluated by a radiologist experienced in assessing the response to IM in GISTs with awareness of their limitations.

No significant financial relationships to disclose.