Lymph node retrieval in pancreaticoduodenectomy specimens: does educating the pathologist matter?

Background:Many previous studies have suggested that the number of lymph nodes retrieved should serve as a benchmark for assessing the adequacy of the resection. The aim was to retrospectively observe the impact of nodal retrieval after educating the pathologist.Methods:Patients undergoing a pancreaticoduodenectomy (PD) between September 2005 and March 2009 were included in the study. The PDs performed between September 2005 and March 2008 were designated as Group A. The pathologistswere educated regarding the importance of nodal counts in PD by the surgeon on the 1st April 2008. PDs performed betweenApril 2008 and March 2009 were designated as Group B.Results:Ninety-eight PDs performed by a single surgeon (D.R.J.) for peri-ampullary malignancy were evaluated. The median number of lymph nodes retrieved in Group A was 11(3–32) nodes. The median number of lymph nodes retrieved in Group B was 22 (10–29) nodes (P < 0.001).The lymph node ratio (positive/total nodes), median number of positive nodes retrieved, and the node positivity (node positive compared to node negative) rate did not change.Discussion:A single intervention with the pathologists did impact the number of lymph nodes retrieved from PD specimens. However, the lymph node ratio and lymph node positivity rate remained unchanged. The pathologist is critical to nodal retrieval in PD, but the use of this lymph node number for benchmark of surgical adequacy may be simplistic.     

Chemoradiation followed by chemotherapy before resection for borderline pancreatic adenocarcinoma

BACKGROUND: For patients with borderline resectable pancreatic cancer, preoperative chemoradiation and standalone chemotherapy may allow for R0 resection and improved survival. METHODS: A retrospective review of patients with borderline resectable pancreatic cancer treated with preoperative chemoradiation and standalone chemotherapy was undertaken. Clinical variables, including disease-free and overall survival, were collected. Univariate analysis was used to identify factors impacting survival. RESULTS: Thirteen patients with borderline resectable pancreatic cancer were treated with preoperative chemoradiation and chemotherapy. Morbidity and mortality were 38% and 0. There were 2 R1 and 11 R0 resections. Nine patients are alive with a median follow-up of 20 months. Five patients recurred at a median of 4 months. Tumor fibrosis < or = 60% was associated with recurrence and poor survival. CONCLUSIONS: Preoperative chemoradiation and chemotherapy allow a select group of patients with borderline resectable pancreatic cancer to undergo an R0 or R1 resection with acceptable morbidity and mortality. Tumor response may be associated with survival.     

Adaptogenic and anti-amnesic properties of Evolvulus alsinoides in rodents

Evolvulus alsinoides (EA) is well known for its memory enhancement, antiepileptic and immunomodulatory properties in the traditional Indian system of medicine, Ayurveda. In view of the increasing attention towards plants offering non-specific resistance (adaptogens) towards stress, we have evaluated crude ethanolic extract of EA for its adaptogenic and memory enhancing properties in rodents. Adaptogenic activity was assessed in rats subjected to acute and chronic unpredictable stress. Male Sprague-Dawley rats, weighing 180-200 g were immobilized for 150 min once only in acute stress (AS) model, whereas in chronic unpredictable stress (CUS) model rats were subjected to different types of stressors daily for 7 days. Stress exposure has induced gastric ulceration with increase in adrenal gland weight, plasma creatine kinase (CK), and corticosterone level in AS and CUS. However plasma glucose was increased only in AS. Rats were treated with graded doses of crude ethanolic extract of EA (100, 200 and 400 mg/kg p.o.) for 3 days and subjected to AS on 3 day after 45 min of last dose. In CUS, EA at a dose of 200 mg/kg p.o. found effective in acute studies was administered 45 min prior to stress regimen for 7 days. EA reduced the stress induced perturbations similar to Panax quinquefolium (PQ) (100 mg/kg p.o.), a well known adaptogen. EA (100 mg/kg) administered orally for 3 days in adult male Swiss mice, was effective in decreasing scopolamine induced deficit in passive avoidance test. The improvement in the peripheral stress markers and scopolamine induced dementia by EA in the present study indicates the adaptogenic and anti-amnesic properties of EA.     

The novel nicotinic receptor antagonist, N,N′-dodecane-1,12-diyl-bis-3-picolinium dibromide (bPiDDB), inhibits nicotine-evoked [H]norepinephrine overflow from rat hippocampal slices

Smoking is a significant health concern and strongly correlated with clinical depression. Depression is associated with decreased extracellular NE concentrations in brain. Smokers may be self-medicating and alleviating their depression through nicotine stimulated norepinephrine (NE) release. Several antidepressants inhibit NE transporter (NET) function, thereby augmenting extracellular NE concentrations. Antidepressants, such as bupropion, also inhibit nicotinic receptor (nAChR) function. The current study determined if a recently discovered novel nAChR antagonist, N,N′-dodecane-1,12-diyl-bis-3-picolinium dibromide (bPiDDB), inhibits nicotine-evoked NE release from superfused rat hippocampal slices. Previous studies determined that bPiDDB potently (IC₅₀ = 2 nM) inhibits nicotine-evoked striatal [³H]dopamine (DA) release in vitro, nicotine-evoked DA release in nucleus accumbens in vivo, and nicotine self-administration in rats. In the current study, nicotine stimulated [³H]NE release from rat hippocampal slices (EC₅₀ = 50 μM). bPiDDB inhibited (IC₅₀ = 430 nM; I_max = 90%) [³H]NE release evoked by 30 μM nicotine. For comparison, the nonselective nAChR antagonist, mecamylamine, and the α7 antagonist, methyllycaconitine, also inhibited nicotine-evoked [³H]NE release (IC₅₀ = 31 and 275 nM, respectively; I_max = 91% and 72%, respectively). Inhibition by bPiDDB and mecamylamine was not overcome by increasing nicotine concentrations; Schild regression slope was different from unity, consistent with allosteric inhibition. Thus, bPiDDB was 200-fold more potent inhibiting nAChRs mediating nicotine-evoked [³H]DA release from striatum than those mediating nicotine-evoked [³H]NE release from hippocampus.     

N,N'-Alkane-diyl-bis-3-picoliniums as nicotinic receptor antagonists: inhibition of nicotine-evoked dopamine release and hyperactivity

The current study evaluated a new series of N,N'-alkane-diyl-bis-3-picolinium (bAPi) analogs with C6-C12 methylene linkers as nicotinic acetylcholine receptor (nAChR) antagonists, for nicotine-evoked [3H]dopamine (DA) overflow, for blood-brain barrier choline transporter affinity, and for attenuation of discriminative stimulus and locomotor stimulant effects of nicotine. bAPi analogs exhibited little affinity for alpha4beta2* (* indicates putative nAChR subtype assignment) and alpha7* high-affinity ligand binding sites and exhibited no inhibition of DA transporter function. With the exception of C6, all analogs inhibited nicotine-evoked [3H]DA overflow (IC50 = 2 nM-6 microM; Imax = 54-64%), with N,N'-dodecane-1,12-diyl-bis-3-picolinium dibromide (bPiDDB; C12) being most potent. bPiDDB did not inhibit electrically evoked [3H]DA overflow, suggesting specific nAChR inhibitory effects and a lack of toxicity to DA neurons. Schild analysis suggested that bPiDDB interacts in an orthosteric manner at nAChRs mediating nicotine-evoked [3H]DA overflow. To determine whether bPiDDB interacts with alpha-conotoxin MII-sensitive alpha6beta2-containing nAChRs, slices were exposed concomitantly to maximally effective concentrations of bPiDDB (10 nM) and alpha-conotoxin MII (1 nM). Inhibition of nicotine-evoked [3H]DA overflow was not different with the combination compared with either antagonist alone, suggesting that bPiDDB interacts with alpha6beta2-containing nAChRs. C7, C8, C10, and C12 analogs exhibited high affinity for the blood-brain barrier choline transporter in vivo, suggesting brain bioavailability. Although none of the analogs altered the discriminative stimulus effect of nicotine, C8, C9, C10, and C12 analogs decreased nicotine-induced hyperactivity in nicotine-sensitized rats, without reducing spontaneous activity. Further development of nAChR antagonists that inhibit nicotine-evoked DA release and penetrate brain to antagonize DA-mediated locomotor stimulant effects of nicotine as novel treatments for nicotine addiction is warranted.     

Sensitive and rapid titrimetric and spectrophotometric methods for the determination of stavudine in pharmaceuticals using bromate-bromide and three dyes

Four sensitive and rapid methods for the determination of stavudine (STV) in bulk drug and in dosage forms were developed and optimized. In titrimetry, aqueous solution of STV was treated with a known excess of bromate-bromide in HCl medium followed by estimation of unreacted bromine by iodometric back titration. Spectrophotometric methods involve the addition of a measured excess of bromate-bromide in HCl medium and subsequent estimation of the residual bromine by reacting with a fixed amount of methyl orange, indigocarmine or thymol blue followed by measurement of absorbance at 520 nm (method A), 610 nm (method B) or 550 nm (method C). In all the methods, the amount of bromate reacted corresponds to the amount of STV. Calculations in titrimetry were based on a 1:0.666 (STV:KBrO3) stoichiometry and the method was found to be applicable over 3.5-10 mg range. A linear increase in absorbance with concentration of STV was observed in the spectrophotometric methods, and the Beer's law was obeyed over the concentration ranges 0.125-1.75, 1-10 and 1-9.0 microg mL-1 STV for method A, method B and method C, respectively. The methods when applied to the determination of STV in tablets and capsules were found to give satisfactory results.     

Outcome and Natural History of Patients with Stage IV Colorectal Cancer Receiving Chemotherapy Without Primary Tumor Resection

Background  

There is a trend toward nonsurgical management of patients with nonobstructing metastatic (stage IV) colorectal cancer (CRC), although some will eventually undergo surgery. We examined patients with metastatic CRC who were managed with an intact primary tumor.     

Use of ceric ammonium sulphate and two dyes, methyl orange and indigo carmine, in the determination of lansoprazole in pharmaceuticals

Two spectrophotometric methods are proposed for the assay of lansoprazole (LPZ) in bulk drug and in dosage forms using ceric ammonium sulphate (CAS) and two dyes, methyl orange and indigo carmine, as reagents. The methods involve addition of a known excess of CAS to LPZ in acid medium, followed by determination of residual CAS by reacting with a fixed amount of either methyl orange, measuring the absorbance at 520 nm (method A), or indigo carmine, measuring the absorbance at 610 nm (method B). In both methods, the amount of CAS reacted corresponds to the amount of LPZ and the measured absorbance was found to increase linearly with the concentration of LPZ, which is corroborated by the correlation coefficients of 0.9979 and 0.9954 for methods A and B, respectively. The systems obey Beer's law for 0.5-7.0 microg mL(-1) and 0.25-3.0 microg mL(-1) for methods A and B, respectively. The apparent molar absorptivities were calculated to be 3.0 x 10(4) and 4.4 x 10(4) L mol(-1) cm(-1) for methods A and B, respectively. The limits of detection (LOD) and quantification (LOQ) were calculated to be 0.08 and 0.25 microg mL(-1) for method A, and 0.09 and 0.27 microg mLs(-1) for method B, respectively. The intra-day and inter-day precision and accuracy of the methods were evaluated according to the current ICH guidelines. Both methods were of comparable accuracy (er < or = 2 %). Also, both methods are equally precise as shown by the relative standard deviation values < 1.5%. No interference was observed from common pharmaceutical adjuvants. The accuracy of the methods was further ascertained by performing recovery studies using the standard addition method. The methods were successfully applied to the assay of LPZ in capsule preparations and the results were statistically compared with those of the literature UV-spectrophotometric method by applying Student's t-test and F-test.