Tripodal Triazine and 1,8-Naphthalimide-based Small Molecules as Efficient Photocatalysts for Visible-light Oxidative Condensation.

Tripodal donor-acceptor (D-A) small molecules Tr-Np3 and Tr-T-Np3 consisting of triphenyl triazine and 1,8-naphthalimide, without and with a thiophene spacer have been synthesized. Their optical and redox properties were thoroughly investigated along with their utilization as photocatalysts in organic transformations. Compounds Tr-Np3 and Tr-T-Np3 showed broad absorption in the range of 290-480 nm in solutions and 300-510 nm in thin films. These tripodal molecules displayed wide optical bandgaps of (Eg opt ) 3.10 eV and 2.64 eV with very deep-lying HOMO energy levels (-6.60 eV and -6.03 eV) and low-lying LUMO levels (-3.50 eV and -3.40 eV). Appreciable electron mobilities of 5.24×10-4  cm2 /Vs and 6.14×10-4  cm2 /Vs were obtained for compounds Tr-Np3 and Tr-T-Np3 respectively by space-charge limited current (SCLC) measurements. Metal-free tripodal molecules Tr-Np3 and Tr-T-Np3 showed excellent photocatalytic abilities towards condensation of aromatic aldehydes and o-phenylenediamine followed by cyclization under visible light to yield benzimidazole derivatives that are of high medicinal value.

Surgical outcomes of single stage surgery for Tandem spinal stenosis (TSS) in elderly and younger patients: A comparative study.

STUDY DESIGN: Retrospective study. OBJECTIVE: To evaluate and compare the outcomes of single stage surgery for Tandem Spinal Stenosis (TSS) in elderly (Age ≥65 years) and younger patients (Age <65 years). SUMMARY OF BACKGROUND DATA: Tandem spinal stenosis among elderly is common and often missed diagnosed with delayed presentation. Literature evaluating efficacy and safety of single staged surgery for TSS in elderly patients is scanty. METHODS: Analysis of 74 patients with TSS managed with single stage posterior surgery from 2007 to 2016 was done. A total of 62 patients who satisfied our inclusion criteria were evaluated and subdivided into two groups based on age; Study group (age ≥65years)] (n = 32) and control group (age <65years) (n = 30). Perioperative, clinical/radiological parameters and postoperative complications and recovery rate were noted. RESULTS: The Mean ODI and mJOA showed significant improvement post-operatively in both groups however there was no significant difference between the two groups at final follow-up. There was no statistical difference in operative time, blood loss and hospital stay between the groups. As per Odom's criteria, 78.1% had excellent to good results in study group, while 83.3% had excellent to good results in control group. Postoperative complications were more in elderly group however, there was no significant difference among neurological or cardiopulmonary complications between both groups. CONCLUSIONS: Single stage surgery is safe & efficacious modality with less morbidity and optimal results in elderly patients with proper preoperative risk assessment. Our study showed that increased age does not proved to be deterrent in the outcome of single staged surgery in tandem spinal stenosis.

Surgical outcomes of posterior trans-facetal decompression and stabilisation in tuberculous spondylodiscitis with neuro-deficit.

STUDY DESIGN: Retrospective study. PURPOSE: To evaluate the functional, neurological and radiological outcomes of posterior trans-facetal decompression and stabilisation in tuberculous spondylodiscitis patients with neuro-deficit. OVERVIEW OF LITERATURE: Spinal tuberculosis mainly involves anterior column and for that anterior approach has been the most frequently used surgical technique in the past as it allows direct access to the infected tissue providing a good decompression. However, anterior surgery is associated with higher morbidity which can be reduced by posterior trans-facetal approach. MATERIALS AND METHODS: The study included 100 Tuberculous Spondylodiscitis patients with neuro-deficit who underwent posterior trans-facetal decompression and stabilisation from 2009 to 2014. Demographic data, clinical parameters (back pain score-VAS, ODI), neurological status (Frankel's grade), radiological parameters (Kyphosis angle) and complications were evaluated. RESULTS: Out of the total 100 patients there were 58 males and 42 females. 84 patients had thoracic and 16 had thoracolumbar region involvement. The mean age of the patients was 34.7 years. The extent of fixation was 2 segments in 52 patients and >2 segments in 48 patients. Postoperatively significant improvement in VAS (pre-op 6.5 ± 0.65 to post-op 1.73 ± 0.64) and ODI (pre-op 76.54 ± 6.96 to post-op 30.5 ± 6.56) were noted. The mean kyphosis angle was corrected from 22.33° ± 5.59° to 5.14° ± 1.32°. 86 patients showed at least 1 grade of improvement in neurology (Frankel's grading) and there was no deterioration in any patient. 3 patients developed superficial infection and 2 had an intra-operative dural tear. 94 patients showed bony fusion at 2 years follow-up. CONCLUSION: Posterior trans-facetal decompression and stabilisation is an effective procedure in the management of thoracic & thoracolumbar tuberculous spondylodiscitis patients with neuro-deficit. It offers circumferential decompression with stabilisation and also maintains kyphosis correction.

Learning Curve of Microendoscopic Discectomy in Single-Level Prolapsed Intervertebral Disc in 120 Patients.

STUDY DESIGN: Retrospective study of prospectively collected data. OBJECTIVE: To evaluate learning curve of tubular microendoscopic discectomy (MED) in lumbar prolapsed intervertebral disc (PIVD) patients based on surgical and clinical parameters and delineate the challenges faced in early cases while practicing MED in large series of patients. METHODS: This study was an institutional review board-approved retrospective study of the first 125 consecutive patients with single-level lumbar PIVD managed with tubular MED from 2008 to 2016 with a minimum 2-year follow-up. A total of 120 patients available at final follow-up were divided into quartiles (30 each) as per the date of surgery, with each consecutive group serving as a control for the previous group. Preoperatively and postoperatively clinical parameters (pain scores [Visual Analogue Scale; VAS], functional disability [Oswestry Disability Index; ODI] score, modified MacNab criteria), perioperative parameters (operative time, blood loss, hospital stay), technical issues (guide wire migration, tube docking-related problems, dural tear), and postoperative complications (postoperative leg pain, neural injury, infection, recurrence) were evaluated. Statistical analysis-logarithm curve-fit regression analysis and ANOVA test. RESULTS: The sample consisted of 75 males and 45 females (mean age: 42.54 years) with no significant difference among the quartiles. There was significant difference (P < .005) noted in mean operative time (quartile 1, 87.33 minutes; quartile 2, 58.5 minutes) and mean blood loss (quartile 1, 76.33 mL; quartile 2, 32.66 mL) between quartile 1 and quartile 2, with no further significant reduction in quartile 3 and quartile 4. Significant difference (P < .005) in clinical parameters (VAS preoperative/postoperative 5.28/0.99; ODI preoperative/postoperative 32.18/12.08) were noted but was not associated with surgical experience. Overall, 90% (108 out of 120) of the patients had good to excellent results according to the modified MacNab criteria. The mean hospital stay did not show any significant difference among the quartiles. Guide wire migrated issues, neural injury, dural tear, and tube docking-related problems were significantly reduced after quartile 1. However, recurrence occurred at any phase. Infection occurred in one patient in quartile 1. Although blood loss and operative time showed a declining trend, it was not significant after quartile 2. So asymptote lay in quartile 1 and we recommend that novice surgeon should perform 25 to 30 cases to achieve mastery in this technique. CONCLUSION: For mastering the art of tubular MED for lumbar PIVD and to reduce its learning curve, novice surgeons can avoid the challenges and problems faced during initial cases with improvement in surgical skills by practicing on cadavers, wet labs, and bone-saw models following certain recommendations that we have after achieving asymptote. Familiarity with instrumentation, communication between surgical team, and defined expectations from radiology technicians are key to reduce the learning curve.

Diagnostic Efficacy, Sensitivity, and Specificity of Xpert MTB/RIF Assay for Spinal Tuberculosis and Rifampicin Resistance.

STUDY DESIGN: A cross-sectional observational study. OBJECTIVE: This study aims to determine the diagnostic accuracy, sensitivity, and specificity of the Xpert MTB/RIF assay (Mycobacterium Tuberculosis/Rifampicin resistance) for the detection of spinal Tuberculosis (TB) and rifampicin (RIF) resistance. SUMMARY OF BACKGROUND DATA: The Spinal TB is often a paucibacillary extra pulmonary tuberculosis which gives a major challenge in early diagnosis and initializing the correct anti-tubercular treatment (ATT). Due to its rapidity and sensitivity, the dependence and reliability on the Xpert MTB/RIF assay has increased in the last few years. The studies describing accuracy of the Xpert MTB/RIF assay in spinal TB are scanty. METHODS: This institutional review board-approved study included 360 diagnosed spinal TB patients. To determine the accuracy of the Xpert MTB/RIF assay, it was compared with other diagnostic tests like histopathology, acid fast bacilli (AFB) smear, culture, and drug sensitivity testing (DST). RESULTS: The Xpert MTB/RIF assay showed 86.3% sensitivity and 85.3% specificity when compared with culture for the diagnosis of Spinal TB and showed 75.86% sensitivity, 96.12% specificity for RIF resistance when compared to DST. Four cases were false positive and 11 cases were false negative for RIF resistance on the Xpert MTB/RIF assay. CONCLUSION: The Xpert MTB/RIF assay is an efficient technique for the rapid diagnosis of spinal TB; however, a clinician should not solely rely on it for starting ATT. As there are false results also with this test which should be read cautiously and be well correlated with culture and DST pattern to guide the start of sensitive drug regimen only. The purpose is to prevent exposure of the second line drugs to false cases found on the Xpert MTB/RIF assay and avoid emergence of new acquired drug resistance. LEVEL OF EVIDENCE: 4.

Superior Facet Joint Violations in Single Level Minimally Invasive and Open Transforaminal Lumbar Interbody Fusion: A Comparative Study.

STUDY DESIGN: Prospective comparative study. PURPOSE: To compare the incidence of iatrogenic superior facet joint violation (SFV) in minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and open TLIF (OPEN-TLIF) at a single lower lumbar fusion level and to evaluate the patient and surgical factors influencing the outcome. OVERVIEW OF LITERATURE: Iatrogenic SFV is a significant risk factor for adjacent segment disease (ASD). Blind screw placement technique in MIS-TLIF contributes to the increasing incidence of iatrogenic SFV which can be influenced by several other potential factors. There are only limited studies comparing the incidence of iatrogenic SFV in MIS-TLIF and OPEN-TLIF. METHODS: In total, 225 cases (450 top screws; MIS-TIFL, 120; OPEN-TILF, 105) undergoing single-level lower lumbar fusion were included in the study. Postoperative computed tomography grading system was used to evaluate iatrogenic SFV. Patient and surgical factors such as age, body mass index, top-screw level, side of the top screw, depth of the spine, and superior facet joint angle (SFA) were analyzed in iatrogenic SFV and non-violation groups to determine their influence on iatrogenic SFV. The clinical outcomes in both groups were assessed preoperatively and postoperatively. RESULTS: The overall incidence of iatrogenic SFV and high-grade violations was higher in MIS-TLIF (41.25%) than in OPEN-TLIF (30.4%). In both groups, bivariate analysis showed a significantly greater incidence of the iatrogenic SFV in patients aged <60 years and those with obesity, top pedicle screws at L4, right-sided top screws, SFA >35°, and depth of the spine >50 mm. CONCLUSIONS: This study demonstrated that the incidence of iatrogenic SFV is greater in MIS-TLIF than in OPEN-TLIF at a single lower lumbar level. MIS-TLIF is effective for lumbar degenerative disease; however, the incidence of iatrogenic SFV was higher. Patient and surgical factors must be considered to protect the facet joints in both TLIF methods to avoid ASD.

The Efficacy of Posterior Cervical Laminectomy for Multilevel Degenerative Cervical Spondylotic Myelopathy in Long Term Period.

STUDY DESIGN: This was a retrospective analysis. BACKGROUND: Surgical decompression is the gold standard for preventing the progression of neurological deficit in degenerative multilevel cervical spondylotic myelopathy (CSM). The efficacy of posterior laminectomy in the surgical management of CSM has been described in the past, but long-term follow-up data are scanty. OBJECTIVE: The aim of this study is to assess the long-term clinical-radiological outcomes following posterior cervical decompressive laminectomy in multilevel degenerative CSM. MATERIALS AND METHODS: A retrospective analysis of 110 patients with degenerative multilevel CSM who underwent posterior cervical laminectomy alone in a single hospital by a single surgeon from 2009 to 2013 with minimum 5-year follow-up. Pre- and post-operative clinical parameters (visual analog scale [VAS], Nurick and modified Japanese orthopedic association [mJOA]), radiological parameter (Sagittal cervical Cobb's Angle), perioperative complications (time, blood loss, and hospital stay), postoperative complications (infection, C5 palsy, and neurological worsening) were evaluated. RESULTS: Totally 110 patients (males - 68 and females - 42) with age varying from 46 to 80 (mean-57) years, and the mean duration of illness was 3 months were evaluated. Mean clinical parameters are VAS (preoperative = 5 ± 1.31, postoperative = 1.49 ± 0.687), Nurick grading (preoperative = 3.23 ± 71, postoperative = 1.924 ± 0.75), and mJOA (preoperative = 6.32 ± 0.87, postoperative = 9.89 ± 1.37). The mean blood loss was 93.95 ± 19.18 ml, and the mean time taken for surgery was 83.65 ± 10.18 min. About 13% (n = 15) patients developed cervical kyphosis and 29% (n = 32) developed changes in cervical spine alignment and 10% (n = 11) developed worsening of neurology at final follow-up. Two patients developed a superficial infection which was managed with antibiotics. Three patients developed C5 palsy which recovered with due time. CONCLUSIONS: With the proper selection of patients, posterior cervical laminectomy is effective in offering a clinical improvement to patients with degenerative multilevel CSM with a low incidence of clinically significant radiological deterioration.

Clinico-Radiological Efficacy of Posterior Instrumentation, Decompression, and Transpedicular Bone Grafting in Osteoporotic Burst Fracture Associated with Neurological Deficit.

OBJECTIVE: The aim of this study is to evaluate clinico-radiological outcomes of posterior surgery (decompression + instrumentation + transpedicular bone graft) in osteoporotic burst fracture associated with neurological deficit [OFND]. MATERIALS AND METHODS: Forty patients with neurological deficit due to delayed osteoporotic vertebral collapse managed by posterior surgery (decompression + instrumentation + transpedicular bone graft) with minimum 2 years follow-up were included in the study. Approval from the Institutional Review Board was taken. Demographic data (age, sex, mode of injury, and the severity of osteoporosis); clinical parameters (Visual Analog Score [VAS], Oswestry Disability Index [ODI], Frankel grade), radiological parameters (local kyphosis), and surgical variables (blood loss, surgery duration, and intraoperative events) were recorded. Neurological worsening/improvement, complications, and implant failures were noted. RESULTS: Significant improvement was noted in VAS (preoperative 8.20 ± 0.65/postoperative 4.1 ± 0.64) and ODI (preoperative 76.54 ± 6.96/postoperative 30.5 ± 6.56). Complete neurological recovery was noted in 37 patients (Frankel Grade E), three patients remained nonambulatory (Frankel Grade C). Significant improvement was noted in local kyphosis angle (preoperative = 21.80 ± 2.70; postoperative 11.40 ± 1.80), with 10% loss of correction (2.5 ± 0.90) at final follow-up. Symptomatic implant failure was noted in two patients and proximal junctional failure in one patient requiring an extension of fixation. CONCLUSIONS: OFND can be managed with a single posterior-only surgery with significant improvement in neurology and functional scores of patients. Aggressive kyphosis correction is often not required and optimal correction of kyphosis is noticed due to prone-positioning alone. Transpedicular grafting is safe and simple alternative to cement augmentation or anterior surgery for collapsed vertebrae.

Surgical, clinical, and radiological outcomes of occipitocervical fusion using the plate-screw-rod system with allograft in craniocervical instability.

OBJECTIVE: We evaluated surgical, clinical, and radiological outcomes of posterior occipitocervical fusion (OCF) using plate-rod-screw construct supplemented with allograft in cases of occipitocervical instability. STUDY DESIGN: This was a retrospective analysis of prospective collected data. METHODS: Data of 52 patients who underwent posterior OCF using plate-screw-rod construct supplemented with allograft at a single institute from 2009 to 2014 were analyzed. Demographics, clinical parameters (Visual Analog Score [VAS], ODI, and mJOA score), functional status (McCormick scale), radiological parameters - mean atlantodens interval, posterior occipitocervical angle, occipitocervical 2 angle, and surgical parameters (operative time, blood loss, hospital stay, and fusion) with complications were evaluated. RESULTS: The mean age of the patients was 54.56 ± 16.21 years with male: female was 28:24. The mean operative time was 142.2 min (90-185 min) and mean blood loss was 250.8 ml. The mean duration of hospital stay was 6.7 days and mean follow-up period was 65.17 ± 5.39 months. There was significant improvement in clinical parameters (modified JOA score, VAS, and Oswestry Disability Index values) postoperatively. Forty patients showed recovery in neurological status at least in Grade 1 in McCormick scale with no neurological deterioration in any patient. Furthermore, radiological parameters at cervicomedullary junction got into acceptable range. Implant-related complications noted in 1 patient and 1 patient had vertebral artery injury. We had dural tear in 3 patients and infection in 2 patients. Fusion was achieved in 46 cases with mean time for fusion was 11.039 months. CONCLUSION: Patients with occipitocervical instability can successfully undergo posterior OCF using plate-screw-rod construct supplemented with allograft with high fusion rate, good clinical and functional outcomes, and low complication rate.

"Plasmo2D": an ancillary proteomic tool to aid identification of proteins from Plasmodium falciparum.

Bioinformatics tools to aid gene and protein sequence analysis have become an integral part of biology in the post-genomic era. Release of the Plasmodium falciparum genome sequence has allowed biologists to define the gene and the predicted protein content as well as their sequences in the parasite. Using pI and molecular weight as characteristics unique to each protein, we have developed a bioinformatics tool to aid identification of proteins from Plasmodium falciparum. The tool makes use of a Virtual 2-DE generated by plotting all of the proteins from the Plasmodium database on a pI versus molecular weight scale. Proteins are identified by comparing the position of migration of desired protein spots from an experimental 2-DE and that on a virtual 2-DE. The procedure has been automated in the form of user-friendly software called "Plasmo2D". The tool can be downloaded from http://144.16.89.25/Plasmo2D.zip.