Inhibition of protein misfolding and aggregation by steroidal quinoxalin-2(1H)-one and their molecular docking studies.

A series of D-ring fused 16-substituted steroidal quinoxalin-2(1H)-one attached to an electron-releasing (ER) or electron-withdrawing (EW) groups via steroidal oxoacetate intermediate were synthesized to investigate their protein aggregation inhibition potential using human lysozyme (HLZ). The influence of the type of substituent at the C-6 positions of the quinoxalin-2(1H)-one ring on the protein aggregation inhibition potential was observed, showing that the EW moiety improved the protein aggregation inhibition potency. Of all the evaluated compounds, NO2-substituted quinoxalin-2(1H)-one derivative 13 was the most active compound and had a maximum protein aggregation inhibition effect. Significant stabilization effects strongly support the binding of the most biologically active steroidal quinoxalin-2(1H)-one with docking studies. The predicted physicochemical and ADME properties lie within a drug-like space which shows no violation of Lipinski's rule of five except compounds 12 and 13. Combined, our results suggest that D-ring fused 16-substituted steroidal quinoxalin-2(1H)-one has the potential to modulate the protein aggregation inhibition effect.

Synthesis, Anti-Fungal Potency and In silico Studies of Novel Steroidal 1,4-Dihydropyridines.

Working principle of azoles as antifungals is the inhibition of fungal CYP51/lanosterol-14α-demethylase via selective coordination with heme iron. This interaction can also cause side effects by binding to host lanosterol-14α-demethylase. Hence, it is necessary to design, synthesize and test new antifungal agents that have different structures than those of azoles and other antifungal drugs of choice in clinical practice. Consequently, a series of steroidal 1,4-dihydropyridine analogs 16-21 were synthesized and screened for their in vitro anti-fungal activity against three Candida species as steroids-based medications have low toxicity, less vulnerability to multi-drug resistance, and high bioavailability by being capable of penetrating the cell wall and binding to specific receptors. Initially, Claisen-Schmidt condensation takes place between steroidal ketone (dehydroepiandrosterone) and an aromatic aldehyde forming steroidal benzylidene 8-13 followed by Hantzsch 1,4-dihydropyridine synthesis resulting in steroidal 1,4-dihydropyridine derivatives 16-21. The results exhibited that compound 17 has significant anti-fungal potential with an MIC value of 750 µg/ml for C. albicans and C. glabrata and 800 µg/ml for C. tropicalis. In silico molecular docking and ADMET studies were also performed for compounds 16-21.

Synthesis, antifungal evaluation, and molecular docking studies of steroidal thiazolopyrimidines.

A series of steroidal thiazolopyrimidine derivatives were developed and evaluated for their antifungal properties against Candida species using steroid as the basic skeletonand a thiazolopyrimidine heterocycle as a pharmacophore in the D-ring. Dehydroepiandrosterone, aromatic aldehydes, and 2-aminothiazole were used in a one-pot multicomponent reaction with silica sulphuric acid to generate the target molecules. Additionally, molecular docking studies were conducted to determine how synthesized steroidal derivatives interacted with the amino acid residues of CYP51 ofCandida albicans.

Microwave-assisted one-pot multicomponent synthesis of steroidal pyrido[2,3-d]pyrimidines and their possible implications in drug development.

Protein misfolding can lead to fibrillar and non-fibrillar deposits which are the signs of countless human diseases. A promising strategy for the prevention of such diseases is the inhibition of protein aggregation, and the most crucial step toward effective prevention is the development of small molecules having the potential for protein-aggregation inhibition. In this search, a series of novel steroidal pyrido[2,3-d]pyrimidines have been synthesized employing steroidal ketone, substituted aldehydes, and 2,6-diaminopyrimidin-4(3H)-one through the microwave-assisted one-pot multicomponent methodology. The aggregation inhibition potential of newly synthesized compounds was evaluated on human lysozyme (HLZ). All the synthesized compounds were found to be efficient in the inhibition of protein aggregation in carefully designed in vitro experiments. Moreover, molecular docking studies also determine the binding interactions between all the synthesized compounds and native HLZ through hydrogen bonding. The structures of synthesized compounds were also elucidated using various spectroscopic techniques.

Gastroenteropancreatic neuroendocrine tumours: Clinicopathological evaluation at Shifa International Hospital, Islamabad.

OBJECTIVE: Clinicopathological features of gastroenteropancreatic neuroendocrine tumours (GEP-NETs) have rarely been studied in Pakistani population. We investigated clinical characteristics of these tumours according to updated World Health Organization (WHO) 2010 classification. METHODS: The data of Shifa International Hospital, Islamabad was retrospectively analysed for pathologically confirmed GEP-NETs from January 2013 to March 2018. RESULTS: One hundred and eighteen patients (mean age, 52.2± 16.4 years; Of these 65(55.1%) were males. Majority, 98(83.1%) of the patients were symptomatic including 6(5.1%) with functional tumours. Pancreas was the most frequent primary site noted in 33(28%) patients. The most common histologic type was well differentiated neuroendocrine tumour (WDNET) in 96(81.4%) patients followed by neuroendocrine carcinoma (NEC) in 11(16.1%) patients. Almost half the cases or 54(45.8%) of WDNET were grade 1, 32 (27.1%) were grade 2, and 10 (8.5%) were grade 3. Distant metastasis at the time of diagnosis was found in 18(15.3%) cases with 14,(77.7%) in liver as the most common metastatic site. Synaptophysin positivity was seen in 60 (96.8%) cases of grade 1, 32(27.2%) of grade 2 WDNET, 8(100%) cases of grade 3 WDNET and 12(92.3%) of NEC and chromogranin was positive in 49(94.2%) of grade 1 and grade 2 WDNET, 5 (83.3%) cases of grade 3 WDNET and 5 (45.4%) cases of NEC. CONCLUSIONS: GEP-NETs showed a wide clinicopathological spectrum. Pancreas is the most common site of involvement by the GEP-NET, however, grade 3 WDNET had a predilection for colon. Small cell carcinoma was commonly observed in the oesophagus.

Is TLE1 Expression Limited to Synovial Sarcoma? Our Experience at Shifa International Hospital, Pakistan.

INTRODUCTION: Synovial sarcoma (SS) accounts for 10-15 percent of adult soft tissue sarcomas. Transducin-like enhancer of split 1 (TLE1), a transcriptional repressor, is essential in hematopoiesis, neuronal differentiation, and terminal epithelial differentiation. TLE1 proteins inhibit Wnt signaling and other cell fate determination signals, and so have an established role in repressing differentiation. TLE1 has recently been shown to be a highly sensitive and relatively specific marker of SS. MATERIALS AND METHODS: Study design is retrospective, descriptive. A total of 25 cases of SS and 28 of soft tissue lesions were retrieved from the record. TLE1 (clone 1F5) expression was evaluated and scored as negative (<5% of cells positive), 1+ (5-25% of cells positive), 2+ (26-50% of cells positive), or 3+ (>50 % of cells positive). RESULT: Twenty-four out of twenty-five (96%) cases of SS showed 3+ TLE1 expression. One (4%) case of poorly differentiated SS showed 2+ positivity. 3+ TLE1 positivity was seen in one (100%) case each of infantile fibrosarcoma and low-grade fibromyxoid sarcoma, while two cases (100%) of schwannoma also showed 3+ positivity. All cases of solitary fibrous tumor) (n=2), clear cell sarcoma of tendons and aponeurosis (n=2), embryonal rhabdomyosarcoma (n=1), and de-differentiated liposarcoma (n=2) showed 2+ positivity. 1+ positivity was seen in alveolar soft part sarcoma (n=2), Ewing's sarcoma (n=4), undifferentiated pleomorphic sarcoma (n=1), myxoid liposarcoma (n=1) and malignant peripheral nerve sheath tumor (n=1). TLE1 was negative in all cases of chordomas (n=2), lipomas (n=2), nodular fasciitis (n=2), malignant perivascular epithelioid cell tumor (n=1) and dermatofibrosarcoma protuberans (n=1). CONCLUSION: TLE1 may be a reliable immunostain for diagnosing SS, but its expression is not limited to SS. Its expression should be interpreted in the light of morphological features and a panel of antibodies.

Accuracy of intra-operative frozen section in the diagnosis of female genital tract neoplasms.

OBJECTIVE: To evaluate the accuracy of intra-operative frozen section in the diagnosis of various pelvic neoplasms, including ovarian tumours. METHODS: The retrospective study was conducted at Shifa International Hospital and comprised records of all patients with lesions of female genital tract who underwent frozen section between January 2010 and December 2012. Comparison was made with the final diagnosis after histopathology was performed on examining permanent paraffin sections. RESULTS: The mean age of the 54 patients was 43.70+/-14.8 years (range: 19-75 years). The frozen section was accurate in 51(92.6%) cases. It had a moderately high sensitivity of 75%, high specificity of 97.6%, high positive predictive value of 90% and high negative predictive value of 93.2%. Lack of agreement was found in cases of ovarian tumours of the mucinous and borderline variety. CONCLUSIONS: Frozen section showed a considerable level of accuracy when dealing with suspected pelvic neoplasms.

Immunoglobulin M Nephropathy in a Patient with Wilson's Disease.

Immunoglobulin M nephropathy (IgMN) is characterized by the deposition of immunoglobulin M in a dominant distribution in the renal glomeruli. Primary immunoglobulin M nephropathy is diagnosed after consistent light microscopy (LM), immunofluorescence (IF), electron microscopy (EM) results, and exclusion of known systemic disorders causing immunoglobulin M deposition in the glomeruli. The secondary disease has been reported with a few conditions though it has never been reported with any primary disease of the liver. We report the case of an adolescent male patient who presented with nausea, vomiting, diarrhea, and worsening anasarca. He was found to have nephrotic-range proteinuria that did not respond to conventional corticosteroid treatment. He was subjected to a renal biopsy which revealed a diagnosis of immunoglobulin M nephropathy. His liver function tests were deranged and an ultrasound scan of the abdomen revealed a coarse irregular liver. Workup revealed elevated urine copper excretion and a low ceruloplasmin level. He was diagnosed as a case of Wilson's disease and started on penicillamine and pyridoxine. He was also started on intravenous cyclophosphamide for the corticosteroid-resistant nephrotic syndrome to which he responded remarkably well. His edema settled, proteinuria resolved, and liver functions normalized. Currently, he is in remission and enjoying good health. To the best of our knowledge, we report the first known association between IgM nephropathy and Wilson's disease. It is presently not clear if causation can necessarily be established. This may be the result of defective IgM clearance by the liver or an altered metabolism of the antibody or immune complexes, as with hepatic-associated immunoglobulin M (IgM) nephropathy. Further studies are needed to elucidate the exact mechanism of this disease.

Evaluation of fine needle aspiration cytology as a screening tool in thyroid lesions.

OBJECTIVE: To assess the efficacy of fine needle aspiration cytology in the evaluation of thyroid lesions. METHODS: The retrospective study comprised data of all patients who presented for fine needle aspiration cytology at the Shifa International Hospital, Islamabad, between January 2009 and April 2011. The data was retrieved from the departmental records and the results were recorded. All cases who underwent subsequent surgery were also retrieved and histopathology results were compared with the cytology results. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy were calculated. RESULTS: Of the 327 patients, the results were inconclusive in 18 (5.5%), benign in 230 (70.3%), suspicious in 64 (19.6%) and malignant in 15 (4.6%) cases. Besides, 59 (18%) of these patients underwent subsequent surgery. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of fine needle aspiration cytology was calculated to be 85.7%, 73.3%, 50%, 94.2% and 76.2% respectively. CONCLUSION: Fine needle aspiration cytology is a reasonably sensitive, specific and accurate initial diagnostic test for pre-operative evaluation of patients with thyroid swellings. The clinicians should be encouraged to use the procedure as it is minimally invasive and easily performed in an outpatient setting.

Delivering endocrinology and reproduction in an integrated modular curriculum.

OBJECTIVE: To ascertain the perceptions of students and faculty of Shifa College of Medicine, Islamabad regarding the delivery of Endocrinology and Reproduction module as a component of the newly introduced Integrated Modular Curriculum. METHODS: A descriptive study, using mixed qualitative and quantitative method, starting from June 6 to August 15 2008. A period of 10 weeks was spent on the study including 8 weeks of planning, 2 weeks of delivery and assessment and a 2 weeks period of post hoc analysis and data collection. A multidisciplinary team of faculty developed themes, clinical cases, objectives and table of specification of the Endocrinology and Reproduction Module for Fourth Year MBBS Class. Continuous assessment was done by theme-based assignments and student presentations. Summative assessment was done by Multiple Choice and Short Answer Questions. Likert scale-based student feedback questionnaire was administered while the students were also encouraged to comment on the module for improvement. Feedback was obtained from the faculty in a similar manner. RESULTS: Out of a class of 86 students, 47 (55%) agreed to a balance between basic and clinical concepts addressed in the module, 21 (24%) agreed that emphasis on clinical concepts was appropriate, 37 (43%) agreed that learning strategies were well integrated, 50 (58%) were of the opinion that the assigned learning material was consistent with the session objectives, while 39 (45%) agreed that case-based instruction was useful, and 40 (47%) students were of the opinion that large group discussion was useful. Faculty feedback was positive towards integrated learning. CONCLUSIONS: Integrated Endocrinology and Reproduction module received mixed response from students. This led us to modify and tailor the curriculum to better cater for the needs of students. Feedback from students and faculty is essential for improvement in the quality of educational interventions.