Identification of potential SARS-CoV-2 Nsp1 inhibitors from Piper sarmentosum Roxb. using molecular docking.

Nsp1 in SARS-CoV-2 is a key protein that increases the virus's pathogenicity and virulence by binding to the host ribosome and blocks the 40S ribosomal subunit channel, which effectively impedes the mRNA translation as well as crippling the host immune system. Previous studies revealed that the N-terminal in Nsp1 is part and parcel of Nsp1 efficiency, and mutations in its core residues have weakened the protein's. This knowledge persuades us to carry out the in silico screening on plant compounds of Piper sarmentosum Roxb. against the five target residues which are Glu36, Glu37, Arg99, Arg124 and Lys125. Potential compounds were tested for their druggability. As a result, we identified five out of 112 compounds including stigmasterol, N-feruloyltyramine, beta-Sitosterol, 13-(1,3-benzodioxol-5-yl)- N-(2methylpropyl) trideca-2,4,12-trienamide and N-(2-methylpropyl) octadeca-2-4dienamide in Piper sarmentosum Roxb. as potential inhibitors for Nsp1. These compounds formed at least a hydrophobic, hydrogen bonding or π-cation interactions with the protein. Furthermore, SwissADME analysis and the number of bindings to the target residues suggest that N-feruloyltyramine is the ideal inhibitor candidate against SARS-CoV-2 at its N-terminal of Nsp1. Lastly, the interaction with N-feruloyltyramine increased flexibility in the loop regions of N-terminal Nsp1, especially residues 54 to 70, with residue 59 showing the highest fluctuation, potentially affecting the protein's stability and function due to the correlation between RMSF and protein function.

Effect of radiographic contrast material exposure on spiral CT attenuation of renal calculi.

RATIONALE AND OBJECTIVES: The authors performed this study to determine whether exposure of renal calculi to radiographic contrast material has an effect on the attenuation values at computed tomography (CT) performed with varying collimation widths. MATERIALS AND METHODS: Renal calculi (23 stones of various composition) were scanned with 1-, 3-, and 10-mm collimation. Stones were then exposed to a solution of radiographic contrast material for 5 minutes, washed with water, and rescanned 36 hours later. The reproducibility of the CT attenuation measurements on different days was evaluated by obtaining measurements in a subset of 16 renal stones on 4 different days. RESULTS: There was no statistically significant change in attenuation after contrast material exposure at narrow collimation. At wider collimation, statistically significant increases were noted in both attenuation and standard deviation. A small amount of variability between readings was noted on different days, with a minimal increase in attenuation each day. Correlation between readings remained very high. CONCLUSION: Exposure of stones to a radiographic contrast material had a statistically significant effect on CT attenuation values only at wide collimation. This may be related to technical factors including volume averaging. Absence of an effect at narrow collimation suggests that the attenuation values of renal stones do not significantly change after exposure to contrast material.

Correction of helical CT attenuation values with wide beam collimation: in vitro test with urinary calculi.

RATIONALE AND OBJECTIVES: Urinary calculi are now commonly detected with helical computed tomography (CT), and it has been proposed that stone composition can be determined from CT attenuation values. However, typical scans are made with a beam collimation of 5 mm or more, resulting in volume averaging and reduction in accuracy of attenuation measurement. The authors tested a model for correction of errors in attenuation values, even at section widths larger than the width of the object. MATERIALS AND METHODS: Human urinary stones were scanned with helical CT at different beam collimation widths. A computer model was used to predict the effect of beam width and stone size on accuracy of measured attenuation. RESULTS: At 3-mm collimation, the model corrected the attenuation readings with an underestimation of 12% +/- 1 (compared with values at 1-mm collimation; 127 stones; diameters of 1.7-11.3 mm). With attenuation measured at 10-mm collimation, the model underestimated the true value by 34% +/- 3 (103 stones), with a significant negative correlation with stone diameter on magnitude of error (diameters of 3.0-11.3 mm). Correlation of data from patient scans with subsequent in vitro scanning of the same stones confirmed the validity of the model, but corrected in vivo scans consistently yielded lower values for the stones than in vitro. CONCLUSION: Volume averaging effects on attenuation in helical CT are predictable in vitro for urinary calculi--and presumably for other roughly spherical structures--as long as section width does not excessively exceed the diameter of the structure.

Helical CT of urinary calculi: effect of stone composition, stone size, and scan collimation.

OBJECTIVE: Helical CT has become the preferred methodology for identifying urinary calculi. However, the ability to predict stone composition, which influences patient treatment, depends on the accurate measurement of the radiographic attenuation of stones. We studied the effects of stone composition, stone size, and scan collimation width on the measurement of attenuation in vitro. MATERIALS AND METHODS: One hundred twenty-seven human urinary calculi of known composition and size were scanned at 120 kVp, 240 mA, and a 1:1 pitch at different collimations. A model, based on the physics of helical CT, was used to predict the effect of scan collimation width and stone size on measured attenuation. RESULTS: At a 1-mm collimation, stone groups could be differentiated by attenuation: the attenuation of uric acid was less than that of cystine or struvite, which overlapped; these were less than the attenuation of calcium oxalate monohydrate, which was in turn lower than that of brushite and hydroxyapatite, which overlapped and showed the highest values. At a wider collimation, attenuation was lower and the ability to differentiate stone composition was lost. Attenuation also decreased with smaller stones. At a 10-mm collimation, some uric acid stones (

Calcium stone fragility is predicted by helical CT attenuation values.

BACKGROUND AND PURPOSE: Helical CT has become the preferred method for imaging urinary calculi, and so it would be useful if data from helical CT could also be used to predict the number of shockwaves (SWs) needed to break a given stone. METHODS AND MATERIALS: We measured the number of SWs required to comminute calcium stones in vitro. RESULTS: The SW requirement correlated with stone size (volume, weight, diameter) and with helical CT attenuation values when the scans were performed at 3-mm collimation. When CT scans were performed at 1-mm collimation, the number of SWs needed for comminution did not correlate with helical CT attenuation values. This result indicates that the correlation with 3-mm scans was attributable to volume-averaging effects, in which smaller stones yield smaller attenuation values. That is, attenuation values from helical CT at larger beam collimation widths contain information about stone size that can be exploited to predict the fragility of calcium stones. We observed that for calcium stones, the number of SWs to comminution was generally less than half the stone CT attenuation value in Hounsfield units. This "half-attenuation rule" predicted the number of SWs needed to complete fragmentation for 95% of calcium stones (24/24 calcium oxalate monohydrate, 13/13 hydroxyapatite, 8/10 brushite stones). CONCLUSION: This in vitro study suggests that it may be possible to predict effective SW dose using helical CT prior to lithotripsy.

Psychiatric and surgical management of male genital self-mutilation.

Cases of genital self-mutilation are usually seen in the general hospital setting and can be difficult to manage especially in those patients who have psychiatric illness. A joint effort between the psychiatric and the surgical services will be required right from the beginning of hospital admission to diagnosis and later, to follow-up. Psychiatric consultation strategies at the different phases of intervention will be needed to cater for the special needs of the surgical team, patient and family. We describe three cases of genital self- mutilators and the general management of these patients.

Renal cell carcinoma with osteosarcomatous differentiation simulating staghorn calculus: a case report and literature review.

We report a case of renal cell carcinoma that showed extensive osteosarcomatous differentiation and simulated a staghorn calculus clinically and radiologically. The literature on osteosarcomatous differentiation in renal cell carcinoma is reviewed.

Informed consent: an evaluation of patients' understanding and opinion (with respect to the operation of transurethral resection of prostate).

The ability of patients to understand and recall information given prior to obtaining written consent was assessed in 55 patients who were due to undergo the operation of transurethral resection of prostate. The patients were also asked their opinion on informed consent. Most patients knew the position of the prostate and the purpose of the operation. Some aspects of the postoperative management and complications were less well remembered. In particular, 18% of the patients could not remember the possibility of retrograde ejaculation despite efforts to emphasize this. Of the patients who returned their questionnaires, 41% did not mind what happened to them provided they were made better; 54% trusted their doctor to do the right thing and did not think detailed explanation was important; 62% felt that consent forms are to protect the doctor's right; still most patients felt that consent forms were necessary. Sub-groups comparison showed no relationship between patients' attitude and their ability to recall information.

Surgical outcome of orchidopexy. II. Trapped and ascending testes.

OBJECTIVE: To review the outcome of orchidopexy in boys with testicular ascent. PATIENTS AND METHODS: The case notes of all the boys who underwent orchidopexy over an 18-year period, under the care of a single consultant, were collected. The reports of patients who at the initial assessment had normally descended testes and subsequently developed maldescent, were reviewed. RESULTS: At the time of the initial assessment, 69 boys (77 testes) had normally descended testes but subsequently developed maldescent. In the intervening period, 37 of these patients (38 testes) had undergone inguinal surgery for a hernia or a hydrocele (trapped testes). The remaining 34 patients had not undergone surgery and were designated as having an 'ascending testis'. The results of surgery were excellent in all but six cases. Of these, five testes failed to reach the bottom of the scrotum and one was excised. A hernial sac was found in 16 of 28 boys with a trapped testis in whom the data was recorded. CONCLUSION: Testicular ascent is uncommon and can occur spontaneously or following ipsilateral groin surgery where scarring is a likely aetiological factor. The results of surgery are usually excellent.

Surgical outcome of orchiopexy. I. Previously unoperated testes.

A total of 1209 undescended testes in 961 boys who had no previous surgery for this problem have been reviewed with particular regard to the outcome of surgery in relation to the pre-operative and intra-operative assessment of the position of the testis. A third of impalpable testes were found at operation in the abdomen, a third in the inguinal canal and a quarter in the superficial inguinal pouch; 1% of all testes and 7% of impalpable testes were absent; 96% of all testes reached the scrotum at operation and this figure included 69% of abdominal and 94% of canalicular testes. In all 24 testes were excised--7 of which were abdominal, 8 canalicular and 9 were in the superficial inguinal pouch. The generalisation that the higher the undescended testis before operation the poorer the result, does not always hold true.