Mechanism unravelling for highly efficient and selective 99TcO4 - sequestration utilising crown ether based solvent system from nuclear liquid waste: experimental and computational investigations.

Selective and efficient separation of pertechnetate (TcO4 -) from nuclear waste is desirable for the safe and secure management of radioactive waste. Here, we have projected dibenzo-18-crown-6 ether (DB18C6) in a highly polar nitrobenzene medium for enhancing the removal efficiency of 99Tc from reprocessing plant low level waste (LLW). An effort was made to determine the stoichiometry of metal-ligand complex by slope ratio method, revealing that one ligand (DB18C6) binds with one TcO4 - moiety. Optimum ligand concentration for 99Tc extraction was evaluated. Relevant interference of the anions was studied systematically. The effect of solution pH was analysed on the extraction efficiency of 99Tc. A kinetic study was carried out for maximum extraction of metal ions. A quantitative stripping study was also achieved for metal ions with a suitable stripping solution. After evaluation of all essential parameters, selectivity and feasibility studies were finally carried out with actual low level reprocessing plant waste to demonstrate a laboratory scale process for effective separation of TcO4 - ions. Density functional theory (DFT) calculations were carried out to understand the nature of the complexation of TcO4 - ion with DB18C6 in different solvents systems and to elucidate the key aspect behind ionic selectivity and enhanced the 99Tc extraction efficiency of DB18C6 in the studied diluent systems. The ΔE and ΔG values for different modeled complexation reactions were evaluated systematically. From the calculated free energy of complexation of TcO4 - with DB18C6, it was observed that the consideration of explicit solvent plays a vital role in predicting the experimental selectivity.

Correction: Mechanism unravelling for highly efficient and selective 99TcO4 - sequestration utilising crown ether based solvent system from nuclear liquid waste: experimental and computational investigations.

[This corrects the article DOI: 10.1039/D1RA07738D.].

Thirty-day readmissions after inpatient laparoscopic cholecystectomy: factors and outcomes.

BACKGROUND: 30-day readmissions are a considerable financial burden on medical institutions due to penalties faced from the Centers for Medicaid and Medicare. METHODS: A retrospective review of 30-day readmissions was performed. The data were subdivided into medical severity-diagnostic related groups 417, 418, and 419, as categorized by the Centers for Medicaid and Medicare. Perioperative variables, diagnostic workup, operative interventions, and postoperative morbidity and outcomes were analyzed. RESULTS: Forty-four (5.9%) readmissions were recorded, of 747 inpatient discharges. The data were further divided into DRGs 417, 418, and 419 with readmission rates of 13.6, 3.6%, and 5.4%, respectively. The highest rate of readmission was within the first 7 days. Etiology was divided into surgical (54.5%) and nonsurgical (45.4%). CONCLUSIONS: Patients with major comorbidities had a higher rate of readmission (P < .05). In 45.4% of the readmissions, the cause was found to be nonsurgical. The surgical team was not consulted in 31.8% of the readmissions.

Effect of glottal dynamics in the production of shouted speech.

In this paper characteristics of speech produced at different loudness levels are analyzed in terms of changes in the glottal excitation. Four loudness levels are considered in this study, namely, soft, normal, loud, and shout. The distinct changes in the excitation of the shout signal are analyzed using electroglottograph signals. The open and closed phases of the glottal vibration are distinctly different for shout signals, in comparison with those for normal speech. It is generally difficult to derive the glottal pulse information from the speech signal due to limitations in inverse filtering. Hence, the effects of changes in the excitation are examined by analyzing the speech signal using methods that can capture the temporal variations of the spectral features. In particular, the recently proposed methods of zero-frequency filtering and zero-time liftering are used in this analysis. It is shown that the closed phase behavior of the excitation at different loudness levels can be seen in the temporal variation of spectral energy in the low frequency (LF) (<400 Hz) region. The ratio of the LF to high frequency energy clearly discriminates the speech produced at different loudness levels. These distinctions in the excitation features are also observed in different vowel contexts and across several speakers.

Laparoscopic loop ileostomy with a single-port stab incision technique.

Loop ileostomy is an effective means of temporary fecal diversion. It is technically easy to create and manage. Moreover, ileostomy closure does not require a formal laparotomy. With the advent of laparoscopy, many of these loop ileostomies are being performed with laparoscopic assistance. Studies have proved the beneficial effects of laparoscopically created loop ileostomy for fecal diversion. Techniques for performing laparoscopic loop ileostomy have been described using two or more 10- to 12-mm ports with Hassan's technique at the umbilical site for pneumoperitoneum creation. We describe a modified technique, wherein pneumoperitoneum is created using a 10-mm port at the site of the future ileostomy, and a second 5-mm port is placed under vision at the umbilical site. This procedure requires minimal intervention and a reduced pneumoperitoneum time. Since the umbilical port site is 5 mm, it does not require closure, and it also reduces the chances of port-site hernia, formation, patient discomfort and scarring. Because intervention is minimally invasive, operative time is reduced, and there is less of chance postoperative ileus and adhesion formation.

Conservative management of idiopathic clubfoot: Kite versus Ponseti method.

PURPOSE: To compare the long-term results of the Kite and Ponseti methods of manipulation and casting for clubfoot. METHODS: 42 patients (with 64 idiopathic clubfeet) were equally randomised to Kite or Ponseti treatments in the early weeks of life. 14 males and 7 females (34 clubfeet) were treated by the Kite method, whereas 13 males and 8 females (30 clubfeet) were treated by the Ponseti method. All the clubfeet were manipulated, casted, and followed up (for a mean of 3 years) by one experienced orthopaedic surgeon. The final results were compared. RESULTS: The success rates for the Kite and Ponseti treatments were similar (79% vs 87%). With the Ponseti method, the number of casts was significantly fewer (7 vs 10); the duration of casting required to achieve full correction was significantly shorter (10 vs 13 weeks); the maximum ankle dorsiflexion achieved was significantly greater (12 vs 6 degrees); and the incidence of residual deformity and recurrence was slightly lower. CONCLUSION: The Ponseti method can achieve more rapid correction and ankle dorsiflexion with fewer casts, without weakening the Achilles tendon.

Spectroscopic characterization of nanocrystalline chromium nitride (CrN).

Nanocrystalline chromiuim nitride has been synthesised by direct gas phase nitridation of nanocrystalline chromia at 1100 degrees C in ammonia-atmosphere. XRD of this material showed formation of single phase CrN with particle size around 20 nm. AFM studies showed particle distribution along with some soft agglomerated nanostructures. Nanocrystalline Cr2O3 and partially-as well as fully--converted nanocrystalline CrN were also investigated using various spectroscopic techniques like XPS, FT-IR, and Raman for gaining insight into the conversion pathways. Spectroscopic investigations of these materials clearly indicate that complete conversion of CrN occurs by nitriding at 1100 degrees C for 4 hrs. The salient spectroscopic features of these nanocrystalline materials with respect to their microcrystalline counterparts are discussed.

Interferon alpha2b inhibits the murine melanoma cell line Cloudman S91 in vivo but not in vitro: a model for studying tumor cell-cytokine interactions.

Interferon alpha2b has recently been shown to improve outcome in patients with metastatic malignant melanoma. The high-dose interferon therapy used is however associated with significant systemic adverse effects. These adverse effects are likely related to the multitude of actions of interferon which in addition to its antineoplastic effects also possesses antiviral and immunomodulating properties. Elucidation of the mechanism of the antiproliferative effects of interferon may allow for the development of agents that possess the antineoplastic properties while being devoid of the other effects that make interferon toxic. In the animal model developed for this study tumors in mice receiving interferon alpha2b grew at a slower rate and achieved a small final tumor volume (3040 +/- 690 vs 1400 +/- 314 mm3 for the control and treated groups respectively, P < 0.05). Furthermore the final tumor weight in the treated group was significantly smaller (1.50 +/- 0.21 g vs 2.76 +/- 0.46 g for the treated and control groups respectively; P = 0.036). The (3-[4,5-Dimethylthiazol-2-y]-2,5-diphenyltetrazolium bromide) (MTT) colorimetric assay failed to reveal any direct effects of interferon alpha2b on this murine melanoma cell line. This antiproliferative effect of interferon alpha2b was in addition found to be independent of alterations in the expression of the angiogenic cytokines vascular endothelial growth factor, basic fibroblast growth factor, and transforming growth factor beta.

Role of laparoscopic cholecystectomy in the management of gangrenous cholecystitis.

BACKGROUND: Laparoscopic cholecystectomy is increasingly being employed as the initial surgical approach in patients with acute cholecystitis. Gangrenous cholecystitis will be unexpectedly encountered in a proportion of these patients. The applicability of laparoscopic techniques and its outcome in this group of patients remain poorly defined. This paper presents our experience with laparoscopic cholecystectomy in the treatment of patients with gangrenous cholecystitis. METHODS: From January 1994 to March 1999, 281 patients underwent laparoscopic cholecystectomy for acute cholecystitis. Operative and histopathologic data were obtained and the subgroup with gangrenous cholecystitis identified (53 of 281, 18.8%). Laparoscopic cholecystectomy was the initial surgical approach in 44 (83%) and was successfully completed in 30 of 44 (68%) patients. Conversion to an open cholecystectomy became necessary in 14 of 44 (32%). A retrospective review comparing these two groups of patients was performed. RESULTS: Of the 44 patients, there were 25 males and 19 females, with a mean age of 64.6 years. Mean duration of symptoms prior to presentation was 2.3 and 2.9 days in the laparoscopic and conversion groups, respectively. Clinical presentation included the presence of right upper quadrant pain (98%), leukocytosis (91%), fever (16.3%), and jaundice (9%). Liver function test abnormalities included elevations of alkaline phosphatase (25%), aspartate aminotransferase (20.4%), alanine aminotransferase (22.7%), and total bilirubin (18.1%). Ultrasonography revealed the presence of gallstones (88.6%), gallbladder wall thickening (52.3%), and pericholecystic fluid (20.5%). Air in the gallbladder wall and intraluminal membranes were present in 2 patients and 1 patient, respectively. Nuclear scans performed in 29 patients revealed cystic duct obstruction in all 29. The rim sign was present in 1 patient. A laparoscopic cholecystectomy was attempted in 44 of 53 patients and was successfully completed in 30 (68%). Conversion to an open procedure became necessary in 14 of 44 (32%). No difference in preoperative factors was noted among the two groups. The mean duration of surgery in patients undergoing a successful laparoscopic cholecystectomy was 107 minutes versus 110 minutes when conversion was necessary. There were no deaths in the study population. Morbidity occurred in 40% of the laparoscopic group and 71% of the conversion group. No patient in the laparoscopic group required admission to the intensive care unit. In contrast, 4 of 14 patients in the conversion group required a mean of 2.6 days in the intensive care unit. Postoperative hospital stay was 3.3 versus 5.5 days in the two groups, respectively. CONCLUSIONS: Preoperative factors did not predict conversion in patients undergoing laparoscopic cholecystectomy for presumed acute cholecystitis who are found to have gangrenous cholecystitis. Duration of surgery is not significantly prolonged and outcome in terms of morbidity, admission to the intensive care unit, and hospital stay are significantly better in patients in whom laparoscopic cholecystectomy is successful.

Carotid artery injuries and their management.

BACKGROUND: Major vascular injuries in the region of the neck are most frequently the result of penetrating trauma. Evaluation and management of patients with injury to Zone II of the neck remains highly controversial. Most studies involve small number of patients with a lack of standardization of the nature of the injury in reporting outcome. It is the purpose of this study to propose a grading scale for vascular injuries in the neck that would allow for more uniform reporting of such injuries. EXPERIMENTAL DESIGN: A retrospective review of all patients treated for penetrating trauma to the neck was performed and the subset of patients with major vascular injuries identified. Data from this group of patients are presented. SETTING: Level II urban trauma center. PATIENTS AND INTERVENTIONS: During the period July 1984 to June 1994, 107 patients were treated for penetrating neck trauma. Injuries to the major arteries of the neck were present in 18 of the 107 patients (16.8%). All injuries were graded on the developed scale. Management protocol was based on the grade of the injury. Grade 1 injuries were managed non-operatively with systemic anticoagulation and low molecular weight dextran. Grade 2 injuries were treated with primary repair. Injuries of Grades 3 and 4 were treated by primary repair or interposition graft. Exceptions were isolated injuries of the external carotid artery, which were treated by ligation alone. RESULTS: Of the 18 patients with carotid artery injuries, 2 had injuries of the external carotid artery, treated with ligation alone. The internal carotid artery was injured in 7 cases. An interposition saphenous vein/PTFE graft was used in all cases. In 9 cases the common carotid artery was injured. Repair was accomplished by a combination of either a primary repair or interposition graft. Overall mortality was 3/16 (16.6%). No new or worsening of neurologic deficit occurred in any patient. CONCLUSIONS: Carotid artery injuries occur in about 17% of patients with penetrating neck trauma. Data regarding management and prognosis in these patients are at best concflicting, in part, due to lack of a standardized classification system. The proposed grading scale is designed to overcome this problem.

Sentinel lymph node dissection for primary cutaneous melanoma: a community hospital's initial experience.

Management of the regional lymph nodes remains the most controversial aspect of treating patients with intermediate-thickness cutaneous melanoma. Prospective studies have failed to demonstrate a significant survival advantage for patients undergoing elective lymph node dissection. The sentinel lymph node dissection (SLND) technique has been proposed as a method of accurately identifying patients with occult metastases in whom a regional lymph node dissection would be indicated. The majority of studies evaluating this technique have come from academic centers, most with dedicated melanoma clinics. This report describes the initial experience with SLND at a community hospital. Fifteen patients with intermediate-thickness primary cutaneous melanoma underwent preoperative lymphoscintigraphy with 99Tc-sulfur colloid. In addition, intraoperative lymphatic mapping using intradermally injected isosulfan blue was performed. Dissection was guided by radioactivity levels (in counts per second) as measured by a hand-held gamma probe. The resected lymph node or nodes were evaluated for micrometastases using routine hematoxylin and eosin staining and immunohistochemistry with S-100 and HMB-45. All patients were followed clinically for any evidence of recurrence. A sentinel node(s) was identified on preoperative lymphoscintigraphy in all 15 patients (100%). A single sentinel node was identified in 11 of 15 (73%), two nodes in 3 (20%), and one node in 1 (6.7%). The hand-held gamma probe reading correlated well with the site marked the "hot spot" (600-15,320 cps for the hot spot versus 10-350 cps for background). The sentinel lymph node was successfully identified and resected in all 15 patients. Blue-stained lymphatics and/or lymph nodes were present in 8 of 15 (53%) cases. Histopathology was negative for evidence of occult micrometastases in all patients. At mean follow-up of 221 days, all 15 patients remain with no evidence of disease. The outcomes for mapping and harvesting the sentinel node at a community institution compare favorably with results at major academic institutions. SLND may therefore be offered to patients with intermediate-thickness cutaneous melanoma in the community hospital setting with regional lymph node dissection and adjuvant interferon alpha-2b as options for patients with nodal micrometastases.

Primary repair of colon injuries: a prospective randomized study.

Due to the results of a 6-year experience with civilian penetrating colon injuries at Mount Carmel/Grace Hospital, in Detroit, Michigan, which had favored primary repair of colon injuries, a prospective randomized study was performed. Seventy-one patients with penetrating colon injuries were entered in a prospective randomized study. Forty-three patients were treated with primary repair or resection and anastomosis, and 28 patients were treated with diversion. The average Penetrating Abdominal Trauma Index score was 25.5 for the primary repair and 23.4 for the diversion groups. The majority of injuries as assessed by the Colon Injury Score (CIS) for the primary repair group were grades 2 (58%) and 3 (28%). The diversion group predominantly had grades 2 (64%) and 3 (25%). There was no significant difference between the two groups. There were 8 (19%) patients with colon and noncolon-related complications in the primary repair group, and 10 (36%) patients with colon, noncolon, and colostomy-related complications in the diversion group. In addition, there were 2 (7%) patients with complications following colostomy reversal. Independent risk factors for adverse outcomes were compared and used to calculate the probability for adverse outcomes with respect to the mode of treatment. The probability for adverse outcomes was statistically greater in the diversion group. An analysis was also made within the primary repair group comparing the subgroups of primary repair with, and without, resection of colon. It appears that the primary repair with resection of colon may have fewer complications; however, this conclusion is based on a statistically insufficient sample size. The authors contend that primary repair or resection with anastomosis is the method of choice for treatment of all penetrating colon injuries in the civilian population despite any associated risk factors for adverse outcomes.

Small bowel laceration from a penetrating extraperitoneal gunshot wound: a case report.

Direct kinetic energy transfer from the path of a bullet may cause intraperitoneal injury even though the path of the bullet remains extraperitoneal. A 45-year-old man sustained a single through-and-through gunshot wound to the abdomen. The path of the bullet appeared superficial but clinically the patient had an acute abdomen. An exploratory laparotomy revealed no penetration of the peritoneum, but did reveal a perforation and contusion to the jejunum. To our knowledge this is the first reported case of a penetrating extraperitoneal gunshot wound with a blast injury to the small bowel.

Post-traumatic pseudoaneurysm of the left hepatic artery initially appearing as upper gastrointestinal hemorrhage secondary to hepatic artery-duodenal fistula. A case study.

Post-traumatic hepatic artery pseudoaneurysm initially appearing as upper gastrointestinal hemorrhage secondary to rupture in the duodenum is rare. Diagnosis was made on selective arteriogram and the patient was managed successfully by ligating the feeding vessel to the aneurysm.

The application of energy-dispersive x-ray fluorescence spectrometry (EDXRF) to the analysis of cosmetic evidence in Indian nail polishes.

The application of energy-dispersive x-ray fluorescence (EDXRF) spectrometry in the quantitative analysis of samples of Indian nail polishes of apparently similar shades from different manufacturers has been examined by evaluating the possibility of detecting spurious material which is marketed under the guise of a popular brand. On the basis of the number of elements detected, and from the ratios of particular elements [Fe/Ti, Fe/Cu, Ti/Cu] the results are very encouraging.