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1.
Dr. Arni Raghavendrarao Raghuram M.Ch. Subbiah Kumar MD Kathamuthu Balamurugan DA Arulmurugan DA Ramiah Krishnan M.Ch. Perichiappan Sivakami BS Eluvathingal Varghese John M.Ch. 《Indian Journal of Thoracic and Cardiovascular Surgery》2006,22(3):178-181
Background Beating heart surgery has now become the commonest technique of doing Coronary Artery Bypass Graft Surgery (CABG) in our country.
It is being used even in such high risk situations like diffuse coronary disease and Critical Left Main stem Stenosis (LMCS)
with good results. The aim of this study is to retrospectively review our results in Off-Pump Coronary Artery Bypass Surgery
(OPCAB) in patients with critical left main stem stenosis.
Methods This study is a retrospective analysis of the data of patients who underwent primary coronary artery bypass surgery. During
the period from April 2003 to September 2005 a total of 64 patients underwent OPCAB procedure for critical LMCS. During the
same period 10 patients underwent CABG on Cardio Pulmonary Bypass (CPB). The age range was 36–77yrs. The sex distribution
was M: F 53∶10. Ten patients were done as emergency. 2 of them were on Intra Aortic Balloon Pump (IABP) support preoperatively.
10 patients were high risk with a Euro score of ≥5.
Results Left Internal Mammary Artery (LIMA) was used in 78% of cases. Average grafts per patient was 2.96. The median ventilation
time was 5.91 hrs. New IABP insertion in postoperative period was required in 1 patient. One patient was reexplored for bleeding.
There was one perioperative myocardial infarction. 57% of patients did not need any blood transfusion. There was no conversion
to CPB. There was no operative mortality. Inotropes were used in ten cases.
Conclusions OPCAB is a safe method of revascularization in patients with critical LMCS. Preoperative IABP is useful in patients with cardiogenic
shock. However, there is a place for CPB in patients needing additional procedures like Mitral Valve repair (MV repair) or
Dor's procedure or when the vessels are very diffusely diseased. Those patients who are unstable despite IABP support may
be managed by Beating heart On Pump (BHOP) technique. 相似文献
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4.
Assist. Prof. Balamurugan Vellayappan Dennis Cheong Salil Singbal Jeremy Tey Yu Yang Soon Cheng Nang Leong Alvin Wong Sein Lwin Chau Hung Lee Pravin Periasamy Simon Lo Naresh Kumar 《Radiology and oncology》2022,56(4):525
BackgroundThe primary objective was to quantify changes in vascular micro-environment in spinal metastases (SM) patients treated with stereotactic body radiotherapy (SBRT) with multi-parametric dynamic contrast enhanced (DCE) magnetic resonance imaging (MRI). The secondary objective was to study plasma biomarkers related to endothelial apoptosis.Patients and methodsPatients were imaged with DCE-MRI at baseline/1-week/12-weeks post-SBRT. Metrics including normalised time-dependent leakage (Ktrans), permeability surface product (PS), fractional plasma volume (Vp), extracellular volume (Ve) and perfusion (F) were estimated using distributed parameter model. Serum acid sphingomyelinase (ASM) and sphingosine-1-phosphate (S1P) were quantified using ELISA. Clinical outcomes including physician-scored and patient-reported toxicity were collected.ResultsTwelve patients (with varying primary histology) were recruited, of whom 10 underwent SBRT. Nine patients (with 10 lesions) completed all 3 imaging assessment timepoints. One patient died due to pneumonia (unrelated) before follow-up scans were performed. Median SBRT dose was 27 Gy (range: 24–27) over 3 fractions (range: 2–3). Median follow-up for alive patients was 42-months (range: 22.3–54.3), with local control rate of 90% and one grade 2 or higher toxicity (vertebral compression fracture). In general, we found an overall trend of reduction at 12-weeks in all parameters (Ktrans/PS/Vp/Ve/F). Ktrans and PS showed a reduction as early as 1-week. Ve/Vp/F exhibited a slight rise 1-week post-SBRT before reducing below the baseline value. There were no significant changes, post-SBRT, in plasma biomarkers (ASM/S1P).ConclusionsTumour vascular micro-environment (measured by various metrics) showed a general trend towards downregulation post-SBRT. It is likely that vascular-mediated cell killing contributes to excellent local control rates seen with SBRT. Future studies should evaluate the effect of SBRT on primary-specific spinal metastases (e.g., renal cell carcinoma).Key words: spine metastases, stereotactic body radiotherapy, DCE-MRI, endothelial apoptosis 相似文献
5.
Yeruva Pavankumar Reddy V. Srinivasadesikan Rengarajan Balamurugan M. C. Lin Shaik Anwar 《RSC advances》2023,13(9):5796
Substituted tetrahydrochromenes and dihydronaphthofurans are easily accessible by the treatment of β-tetralone with trans-β-nitro styrene derived Morita–Baylis–Hillman (MBH) acetates through a formal [3 + 3]/[3 + 2] annulation. The reaction proceeds through a cascade Michael/oxa-Michael pathway with moderate to good yields. A DFT study was carried out to account for the formation of the corresponding six and five-membered heterocycles via 6-endo-trig and 5-exo-trig cyclization.A [3 + 3] and [3 + 2] annulation strategy using nitrostyrene derived MBH primary and secondary nitro allylic acetate for the construction of tetrahydrochromenes and dihydronaphthofurans at room temperature.The ability to synthesize diverse molecules utilizing nitro allylic MBH acetates in various cascade reactions has received considerable interest.1 A few molecules synthesized using nitro allylic acetates have shown promising cytotoxic, trypanocidal and AchE inhibition2 activity in pharmaceutical and medicinal chemistry. Nitro allylic MBH acetates have been used as main precursors in organocatalysis3 and heterocyclic chemistry,4 and as bicyclic skeletons5 for the construction of elegant building blocks like tetrahydro-pyranoquinolinones,6 sulfonyl furans,7 pyranonaphthoquinones,8 arenopyrans/arenylsulfanes,9 triazoles,10a tetrasubstituted furans,10b fused furans,10c,d tetrasubstituted pyrroles,11a benzofuranones,11b and tetrahydropyrano scaffolds/pyranocoumarins.12 The nitro allylic MBH-acetates can also undergo asymmetric benzylic13a and allylic alkylation13b reactions as well as kinetic resolution [KR]13c,d under normal conditions. These acetates undergo a range of cascade [2 + 3],14 [3 + 2]15 and [3 + 3]16 ring annulation reactions using different substrates. They have been widely utilized in [3 + 2]17a and [3 + 3]17b annulation reactions due to their unique nature of 1,2-/1,3-biselectrophilic reactivity to form either five or six membered rings depending on the nature of nucleophiles employed in the reaction17c,d These adducts are also stable under NHC catalytic conditions to yield cyclopentanes.18Peng-Fei Xu et al. (Scheme 1, eqn (a)) synthesised tetrahydropyranoindoles through organocatalytic asymmetric C–H functionalization of indoles via [3 + 3] annulation through 6-endo trig cyclization.19 The Namboothiri group recently developed a metal free regioselective synthesis of α-carbolines via [3 + 3] annulation involving secondary MBH acetate (Scheme 1, eqn (b)).20 Previously, our group carried out a [3 + 3] cyclization reaction of β-naphthol with primary MBH acetate to study the scope of SN2′ vs. SN2 reaction.21 With our ongoing interest in using nitro styrene derived MBH adducts22 explored the reactivity of primary and secondary MBH acetate with β-tetralone 1 as our model reaction. Initially, the reaction carried out using β-tetralone 1 with primary MBH-acetate 2, predominantly gave a tetrahydrochromene 3via [3 + 3] annulation involving 6-endo trig cyclization through Michael/oxa-Michael cascade process. The possible dihydronaphthofuran product was not observed under the present conditions as primary MBH acetate 2 acts as 1,3-biselectrophile instead of 1,2-biselectrophile (Scheme 1, eqn (c)).Open in a separate windowScheme 1[3 + 3] and [3 + 2] annulation reactions using 1°- and 2°-nitro allylic MBH acetate.On the other hand, the reaction of β-tetralone 1 with secondary MBH acetate 4 gave dihydronaphthofuran instead of the possible tetrahydrochromene product due to the 1,2-biselectrophile nature of secondary MBH acetate (Scheme 1, eqn (d)). The formation of dihydronaphthofuran 5 occurs in an SN2′ fashion via [3 + 2] annulation involving 5-exo-trig cyclization through Michael followed by intramolecular oxa-Michael reaction with the elimination of HNO2. Subsequently, we have carried out a DFT calculation to prove the formation of tetrahydrochromene 3 using primary MBH acetate 2 and dihydronaphthofuran 5 in the case of secondary MBH acetate 4.Initially, we carried out the optimization conditions for constructing tetrahydrochromenes 3a using β-tetralone 1 with MBH nitro allylic primary acetate 2a with different bases and solvents. Reaction with organic base, i.e. DABCO using a polar aprotic solvent such as acetonitrile at room temperature gave the desired product in 27% (23 (CCDC-2149875) ( Entry Base Solvent Time (h) Yield (%) drb 1 DABCO CH3CN 5 27 99 : 1 2 DABCO CH2Cl2 5 22 99 : 1 3 DABCO CHCl3 5 19 99 : 1 4 DMAP THF 5 40 99 : 1 5 TEA THF 5 45 99 : 1 6 PPh3 THF 5 44 99 : 1 7 K2CO3 THF 4 60 99 : 1 8 Cs 2 CO 3 THF 4 77 99 : 1 9c Cs2CO3 THF 8 50 99 : 1 10d Cs2CO3 THF 5 61 99 : 1 11e Cs2CO3 THF 4 65 99 : 1 12f Cs2CO3 THF 4 60 n.d