Silymarin-laden PVP-PEG polymeric composite for enhanced aqueous solubility and dissolution rate: Preparation and in vitro characterization / 药物分析学报

The aim of this work was to develop, optimize and characterize a silymarin-laden polyvinylpyrrolidone (PVP)-polyethylene glycol (PEG) polymeric composite to resolve low aqueous solubility and dissolution rate problem of the drug. A number of silymarin-laden polymeric formulations were fabricated with different quantities of PVP K-30 and PEG 6000 by the solvent-evaporation method. The effect of PVP K-30 and PEG 6000 on the aqueous solubility and dissolution rate was investigated. The optimized formula-tion and its constituents were characterized using powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) techniques. Both the PEG 6000 and PVP K-30 positively affected the aqueous solubility and dis-solution rate of the drug. In particular, a formulation consisting of silymarin, PVP K-30 and PEG 6000 (0.25/1.5/1.5, w/w/w) furnished the highest solubility (24.3972.95 mg/mL) and an excellent dissolution profile (～100％ in 40 min). The solubility enhancement with this formulation was ～1150-fold as com-pared to plain silymarin powder. Moreover, all the constituents existed in the amorphous state in this silymarin-laden PVP-PEG polymeric composite. Accordingly, this formulation might be a promising tool to administer silymarin with an enhanced effect via the oral route.

Optimal primary surgical management of infected pseudoaneurysm in intravenous drug abusers: ligation or reconstruction?

Objective: To find out the optimal primary surgical treatment options for infected pseudoaneurysm in intravenous drug abusers. Study Design: Cross sectional descriptive study. Place and Duration of Study: Department of Vascular Surgery, Combined Military Hospital Lahore, from Jan 2010 to Jun 2015

Material and Methods: A total of 31 consecutive patients with a history of intravenous drug abuse and an infected pseudoaneurysm in the groin or elbow, presenting in emergency department; were included in this study. All patients were primarily treated with ligation of the artery, excision of infected pseudoaneurysm and debridement of necrotic tissues. Only one patient underwent additional revascularization procedure

Results: All patients who underwent ligation and excision procedures did well initially. One [3.2%] patient developed severe distal ischemia after ligation of femoral artery within first 24 hours, so extra anatomic revascularization procedure was performed. Five [16.1%] patients required revascularization procedure after 16 weeks due to disabling distal ischemia. No amputation was needed and mortality rate was zero

Conclusion: Primary ligation of the artery with excision of infected pseudoaneurysm and necrotic material was found the optimal initial management for infected pseudoaneurysm in intravenous drug addicts. Ischemic complications if develop should be treated with early or late revascularization

Patency of autologous reverse great saphenous vein versus polytetrafluroethylene in below knee femoro popliteal bypass grafting

Objective: to compare the patency rates of autologous saphenous vein and expanded polytetrafluroethylene graft in femoropopliteal below knee bypass grafting in patients with peripheral vascular disease

Study design: comparative study

Place and Duration of Study: department of Vascular Surgery Combined Military Hospital Lahore, from January 2011 to January 2013

Methodology: patients with disabling intermittent claudication, rest pain, impending gangrene were included. All patient had duplex scan of the affected limb to assess the velocity of the blood flow in infrainguinal vessels as well as. CTA from infra-renal aorta onwards distally. At operation popliteal artery was assessed for patency and runoff. Great saphenous vein was also assessed for diameter [at least 4mm was labeled as suitable]. In non-suitable cases PTFE was used

Results: a total of 200 bypasses were performed in 190 patients. Of these, 102 [51%] patients had reverse saphenous vein bypass [RSVB] graft and 98 [49%] received expanded polytetrafluroethylene [e-PTFE] graft. Common indications of operation were intermittent claudication in 101 [50.5%] and rest pain in 70 [35%] patients. At 3 year post surgery seven [3.7%] patients were lost to follow-up and 36 [19%] died. Primary patency rate for e-PTFE graft was 62.9% while it was 86.4% for RSVB graft [p =0.032]. The secondary patency rate in e-PTFE graft was 64.1% and in RSVB graft 85.1% [P = 0.034]

Conclusion: saphenous vein graft had a superior patency rates at all intervals of time and it needed lesser redo operations when compared with e-PTFE graft

Abdominal aortic aneurysm rupture masquerading as intestinal obstruction - a rare presentation

We describe a case of a 70 year old man who presented with large bowel obstruction but the physical examination deterred initial diagnosis and raised suspicion of ruptured abdominal aortic aneurysm [AAA]. Subsequent investigations confirmed ruptured AAA. An immediate open surgical repair was performed and patient made a successful recovery. Ruptured AAA masquerade numerous diagnoses including large bowel obstruction; clinicians should anticipate and treat this challenging entity timely

Background: Among vascular diseases, AAA approximately affects 2% of the western population1. AAA is characterized by a dilatation of the localized segment of aorta more than 1.5 times than its normal calibre. Rupture of AAA is the most life threatening surgical emergency with an overall mortality ranging from 32% to 90%2. At present, there is significant scarcity of literature regarding aortic disease in Pakistan. We report a first ever successful surgical repair of a ruptured AAA with a confounding clinical presentation of large bowel obstruction in Pakistan

Role of operative lumbar sympathectomy in patients with critical lower limb ischemia not amenable to vascular reconstructive surgery

Objective: To assess the effectiveness of operative lumbar sympathectomy [LS] in patients with unreconstructable lower limb peripheral vascular disease

Study design: Cross sectional study

Place and Duration of study: Department of Vascular Surgery Combined Military Hospital [CMH] Lahore, from May 2012 to May 2015

Methodology: A total of 117 LS were performed in 105 patients fulfilling the inclusion criteria. The indications for operation were rest pain only in 61 [52.1%], rest pain with trophic changes in 24 [20.5%] and distal gangrene in 32 [27.3%] patients. Duplex scan was done and ankle brachial pressure index [ABPI] was measured preoperatively. Patients were assessed for pain using Visual Analog Scale [VAS] and improvement in trophic changes. All patients were followed up for one year documenting improvement of pain, healing of trophic lesions and / or amputations

Results: At 6 weeks postoperatively, 85 [72.6%] patients became pain free [p = 0.008], and at one year follow up 60 [51.2%] patients remained pain free [p = 0.002] when compared with preoperative pain scores. Pain improvement was more in patients with ABPI of 0.3 or more. The limb salvage rate was 67.6%. Thirty-eight [32.4%] patients end up in amputations. There was no mortality in this series

Conclusions: LS has a role in the management of ischemic symptoms and limb salvage in patients not amenable to vascular reconstruction. Preoperative ABPI has prognostic value in postoperative outcome, with clinical improvement if it is more than 0.3. Smoking was a negative predictive factor in our series

Carotid endarterectomy under local anaesthesia is safe and effective in high risk elderly patients

Objective: to assess the safety and effectiveness of carotid endarterectomy [CEA] under local anaesthesia [LA] in high risk elderly patients

Study design: descriptive case series

Place and Duration of study: department of Vascular Surgery Combined Military Hospital Lahore, from January 2011 to January 2015

Methodology: patients with 70% or more stenosis of internal carotid artery in asymptomatic patients while 50% or more in patients with symptomatic carotid artery disease on duplex scanning were included. They underwent endarterectomy under local anaesthesia. The indication of surgery, hospital stay, complications and mortality were noted

Results: a total of 126 CEA in 112 patients [96 males and 16 females] were performed under LA. Four [3.1%] cases were converted to general anaesthesia [GA]. Shunt was used selectively in 6 [4.7%] cases with bilateral severe carotid artery occlusive disease. Perioperative transient ischaemic attack occurred in 3 [2.3%] patients and permanent neurological deficit in one [0.8%] patient. There was no mortality in this series. The postoperative complications included haematoma formation in 4 [3.1%], bleeding in 3 [2.3%], temporary dropping of lower lip in 1 [0.8%] and pseudoaneurysm formation in 1 [0.8%] patient. Hospital stay ranged from 24 to 96 hours. Mean stay in patients who had CEA under LA was 28 hours while it was 52 hours in those who needed conversion to GA

Conclusion: carotid endarterectomy under local anaesthesia is safe and effective procedure in elderly and high risk patients

Is laparoscopic cholecystectomy a safe treatment option in empyema of gall bladder?

To find out the effectiveness and safety of laparoscopic cholecystectomy for treatment of empyema gallbladder. Quasi-experimental study. PNS Shifa Karachi and CMH Lahore, Pakistan from January 2010 to August 2013. Out of 493 patients who underwent laparoscopic cholecystectomy [LC] by a single consultant surgeon during the study period, 40 patients who had empyema gall bladder on laparoscopic findings were included in the study. All patients with diagnosis of acute cholecystitis [n=117] who had no pus present in gall bladder and patients with diagnosis of biliary colic or chronic cholelithiasis [n=336] were excluded from the study. Forty patients were diagnosed to have empyema gall bladder. LC was successfully completed in 39 patients [97.5%]. In one patient [2.5%] the procedure was converted to open cholecystectomy [OC] due to finding of cholecystoduodenal fistula on laparoscopy. Mean operating time was up to 58.62 +/- 26.33 minutes. Postoperative complications occurred in 3 [7.5%] of the operated patients. Mean duration of hospital stay was 1.7 +/- 2.09 days. One patient with co-morbidity of diabetes mellitus died of septicemia resulting in a mortality rate of 2.5%.In laparoscopy for empyema gallbladder the complications are related to the advanced disease process and not to the approach. In skilled hands, laparoscopic cholecystectomy can be performed successfully in patients with diagnosis of empyema gallbladder