Effects of active compounds from Cassia fistula on quorum sensing mediated virulence and biofilm formation in Pseudomonas aeruginosa

Pseudomonas aeruginosa infections are attributed to its ability to form biofilms and are difficult to eliminate with antibiotic treatment. Biofilm formation is regulated by quorum sensing (QS), an intracellular bacterial communication mechanism that allows the activation of numerous virulence factors and secondary metabolites. Targeting the QS pathway is a potential approach that prevents QS-controlled phenotypes and biofilm formation. For the first time, the current work has identified antiquorum sensing activity in the partially purified four fractions from the hot ethyl acetate extract of Cassia fistula fruit pods. Of the four fractions, only fraction-1 gave decreased AHL activity; the phytoconstituents in this fraction were identified as rhein, 3-aminodibenzofuran, 5-(hydroxymethyl)-2-(dimethoxymethyl)furan, and dihydrorhodamine. Fraction-1 (1 mg ml⁻¹) and rhein (0.15 mg ml⁻¹) showed 63% and 42.7% reduction in short-chain AHL production, respectively, without hindering the bacterial growth. Fraction-1 inhibited QS-mediated extracellular virulence factors viz. protease, elastase, pyocyanin, and rhamnolipid (p < 0.05). Quantitative analysis of biofilm formation showed 77% & 62.4% reduction by fraction-1 (1 mg ml⁻¹) and rhein (0.15 mg ml⁻¹) respectively. Confocal laser microscopy (CLMS) & scanning electron microscopy (SEM) confirmed the reduction of biofilm formation in Pseudomonas aeruginosa upon treatment with fraction-1 and rhein. Moreover, the in vivo study displayed that fraction-1 and rhein (standard) significantly enhanced the survival of Caenorhabditis elegans by suppressing the potency of virulence factors of Pseudomonas aeruginosa. Quantitative real-time polymerase chain reaction results demonstrated the down-regulation of QS-related genes, lasI, lasR, rhlI, and rhlR. In addition, in silico analysis divulged that a component identified by GC-MS displayed a strong affinity towards LasI and LasR. These findings suggest that potent phytochemicals from fraction-1, including rhein, could serve as novel phytotherapeutics in controlling emerging infections of antibiotic-resistant bacterial pathogens like Pseudomonas aeruginosa.

Pseudomonas aeruginosa infections are attributed to its ability to form biofilms and are difficult to eliminate with antibiotic treatment.     

Clinical profile and distribution of peripheral retinal changes in myopic population in a hospital-based study in North India

Purpose:To evaluate the prevalence of different types of peripheral retinal changes in a myopic population in North India and correlate them with axial length.Methods:This cross-sectional, hospital-based survey included 600 eyes of 300 myopic individuals, aged between 10 and 40 years, attending the outdoor ophthalmology clinic of a tertiary eye care hospital in North India were examined from July 2019 to July 2020. They were divided into mild, moderate, high, and severe myopia according to the spherical equivalent of refraction. Axial length was recorded. Peripheral retinal changes were examined by scleral indentation binocular indirect ophthalmoscopy. Standardized findings considered with their fundus location were lattice degeneration, white without pressure and white with pressure, snail-track degenerations, peripheral chorioretinal atrophy, retinal holes, tears, and detachment. The study was approved by the institutional ethics committee, and all participants provided informed consent.Results:Peripheral retinal degenerations were found in almost half (53%) of all myopes included in the study. The most common peripheral retinal degeneration found was lattice degeneration, followed by white without pressure, white with pressure, and chorioretinal atrophy. Most of the peripheral retinal degenerations were seen in the temporal quadrant of the fundus, either superotemporal or inferotemporal. There was a significant positive association between the prevalence of peripheral retinal degeneration with age, increased axial length, and severity of myopiaConclusion:The results of our study indicate the necessity for careful peripheral fundus examinations of all myopes, irrespective of age and degree of myopia, for early diagnosis and better management of visual-threatening complications like retinal detachment.     

Synthesis and preliminary evaluation of difluorinated 1,3-propanediones as potential agents in the treatment of breast cancer

A series of difluorinated propanediones were synthesized and evaluated for in vitro cytotoxic activity by Sulforhodamine B (SRB) assay against a panel of four human cancer cell lines. Though the compounds showed varying degrees of cytotoxicity in the tested cell lines, most marked effect was observed in breast cancer cell line (MCF7), wherein nine of the ten synthesized chalcones showed good antiproliferative activity.     

Deep vein thrombosis and thromboprophylaxis in arthroscopic anterior cruciate ligament reconstruction

Background:

There is no clear evidence in the literature regarding the incidence of deep vein thrombosis (DVT) in patients undergoing arthroscopic anterior cruciate ligament (ACL) reconstruction. Literature also lacks on the recommendations on thromboprophylaxis in patients undergoing elective arthroscopic ACL reconstruction. We conducted a prospective analysis to assess incidence of DVT in patients undergoing arthroscopic ACL reconstruction.

Materials and Methods:

120 consecutive patients with MRI proven ACL injury who were operated for arthroscopic ACL reconstruction were enrolled in this prospective study. None of the patients had risk factors (on history) for DVT, and all were below the age of 45 years. All cases were operated upon by a single surgeon and a standard rehabilitation regime was followed. The patients underwent clinical examination and screening (Doppler ultrasonography/venous scan) for any DVT, on the day prior to surgery, day of discharge (Day 3) and at 4 weeks postsurgery. None of the patients received any form of thromboprophylaxis against DVT.

Results:

One hundred and twelve patients (61 males and 51 females) completed the study. The average age was 31.6 years (range 24-42 years). All patients underwent arthroscopic assisted ACL reconstruction surgery within 3 weeks of the injury. Two patients (males) in the series had Doppler venous scan proven DVT. One patient was asymptomatic but the screening Doppler picked up the DVT on the third postoperative day. The other patient was symptomatic at 12 weeks with pain and swelling in the leg and had ultrasound -proven DVT.

Conclusion:

In our study the incidence of deep vein thrombosis in patients undergoing arthroscopic ACL reconstruction is 1.78%. We do not recommend routine thromboprophylaxis in patients, who are not high risk candidates for thrombosis and are of less than 45 years, in patients undergoing arthroscopic ACL reconstruction, with early postoperative rehabilitation.     

Pseudoaneurysm after Ponseti percutaneous Achilles tenotomy: a case report

The Ponseti method has become a popular technique to treat idiopathic clubfoot. In most cases, a percutaneous Achilles tenotomy is required to correct residual equinus contracture. Bleeding has been reported as a complication of percutaneous tenotomy. We present a case of a baby who developed a pseudoaneurysm after undergoing an appropriate Ponseti percutaneous Achilles tenotomy at the age of 8 weeks. The diagnosis of pseudoaneurysm was confirmed by color ultrasonography, which showed active flow in the base of the mass. This complication has not been previously described after Ponseti percutaneous Achilles tenotomy. The large pseudoaneurysm mass together with an incomplete correction made bracing with straight last shoes and Denis Browne bar impossible, and the patient developed an immediate relapse of the clubfoot deformity. The relapsed deformity was successfully treated with 4 weeks of additional Ponseti casting, with an emphasis on applying pressure over the pseudoaneurysm by molding the cast. Repeat ultrasonogram at that time showed that the pseudoaneurysm completely resolved, making invasive treatment of the pseudoaneurysm unnecessary. Physicians should be aware that vascular injury could lead to pseudoaneurysm after performing this otherwise simple office procedure.     

Role of intraoperative Iso-C based navigation in challenging spine trauma

Background:

Pedicle screw fixation is the most preferred method of stabilizing unstable spinal fractures. Pedicle screw placement may be difficult in presence of fractured posterior elements, deformed spine, gross instability and spinal pathology. Challenging spine-fracture fixation is defined as the presence of one or more of the following: 1) obscured topographical landmarks as in ankylosing spondylitis, 2) fractures in occipitocervical or cervicothoracic regions and 3) preexisting altered spinal alignment. We report a series of pedicle screw insertion with guidance of navigation in difficult fixation problems..

Materials and Methods:

Fourteen patients [hangman''s fracture (n=3), odontoid fracture (n=4), C1C2 fracture (n=1) and spinal fracture with coexistent ankylosing spondylitis (n=6)] underwent posterior stabilization. Intraoperatively after surgical exposure, images were acquired by Iso-C 3D C-arm and transferred to navigation system. Instrumentation was performed with navigational assistance. Postoperatively, placements of pedicle screws were evaluated with radiographs and CT scan.

Results:

Sixty-seven pedicle screws (cervical, n=33; thoracic, n=6; lumbar, n=26; sacral n=2) and 15 lateral mass screws were inserted with navigation guidance. The average time of image data acquisition by Iso-C 3D C-arm and its transfer to workstation was 4 minutes (range, 2-6 minutes). Postoperative CT scan revealed ideal placement of screws in 63 pedicles (94%), grade 1 cortical breaches (<2 mm) in 3 pedicles (4.5%) and grade 2 cortical breach (2-4 mm) in one pedicle (1.5%). There were no neurovascular complications. Deep infection was encountered in one case, which settled with debridement.

Conclusions:

Intraoperative Iso-C 3D C-arm based navigation is a useful adjunct while stabilizing challenging spinal trauma, rendering feasibility, accuracy and safety of pedicle screw placement even in difficult situations.     

Factors Predicting the Oculomotor Nerve Palsy following Surgical Clipping of Distal Vertebrobasilar Aneurysms: A Single-Institution Experience

Background The aim of our study was to identify various clinical and radiologic factors that correlate with the oculomotor nerve palsy following clipping of distal vertebrobasilar aneurysms. Methods A total of 48 patients with 51 aneurysms were included in this retrospective study . Patient''s age, gender, size, location, and projection of the aneurysm, preoperative Hunt and Hess (H&H) grade, presence of subarachnoid hemorrhage (SAH), temporary clipping, preoperative third nerve palsy, and Glasgow Outcome Scale were included in the model for analysis. Results A total of 15 patients (31.25%) developed oculomotor nerve palsy following clipping of basilar apex aneurysms. 38 patients (79.2%) presented with SAH and 35 patients (72.9%) had poor H&H grades at presentation. The size of the aneurysm (p = 0.03), preoperative H&H grade (p = 0.04), preoperative oculomotor nerve dysfunction (p = 0.007), and projection of an aneurysm (p = 0.004) had shown a significant correlation with the oculomotor nerve palsy. The size of the aneurysm (p = 0.030, odds ratio: 0.381; 95% confidence interval, 0.175–0.827] was an independent predictor of postoperative nerve dysfunction. Conclusion The size of the aneurysm, clinical grade at presentation, and projection of the aneurysm correlated with the oculomotor nerve dysfunction following clipping. These clinical and radiologic parameters can be used to predict the oculomotor nerve outcome.     

Quantitation of Fetal Heart Function With Tissue Doppler Velocity Imaging—Reference Values for Color Tissue Doppler Velocities and Comparison With Pulsed Wave Tissue Doppler Velocities

Quantitative assessment of fetal heart function has been difficult. Increasingly, tissue Doppler imaging (TDI) is used to measure fetal cardiac function noninvasively. There are two principal techniques, spectral pulsed wave (PW) TDI and color TDI (CTDI). Published reference values for fetal myocardial velocities are based on spectral PW TDI only. However, previous phantom, adult, and animal studies have shown that PW TDI velocities are systematically higher than CTDI velocities. There are no fetal studies so far. We hypothesized that myocardial velocities derived by PW TDI and CTDI are significantly different in the fetus. This prospective observational study included 91 fetuses (gestational age 28.6 ± 6.6 weeks; range 19–40 weeks) seen for routine prenatal ultrasound. From apical 4‐chamber views, tricuspid ring (right ventricle), lateral and septal mitral ring were sampled by PW TDI and CTDI. Bland–Altman analysis was used for comparisons. PW and CTDI S′ velocities correlated strongly in all three cardiac segments (r = 0.6 to 0.9; P < 0.01). There was a systematic bias toward higher velocities with PW TDI versus CTDI (bias 0.96 cm/s; 95% CI 1.08–0.85 cm/s). However, the strength of the correlation and bias varied depending on the region of the fetal heart sampled. PW TDI and CTDI velocity measurements are feasible in the fetus and correlate well. However, PW TDI velocities are higher than CTDI velocities with significant regional variation. This precludes a mathematical conversion of PW to CTDI in vivo. As PW TDI and color TDI vary, different reference values for fetal CTDI velocities were generated.