ABSTRACT
Two fluorometric sensors based on the tri-serine tri-lactone scaffold and thiourea or sulfonamide moieties serving as hydrogen bond donors allowing for anion binding are described. The sensor utilizing thiourea as a recognition moiety shows fluorescence enhancement while the sensor with sulfonamide shows quenching upon addition of phosphates. Sensor arrays composed of two sensors are able to discriminate structurally similar organic phosphates in the presence of interferents in human blood serum. The quantitative analysis of ATP in human blood serum shows high accuracy (the root mean square error of prediction, 1.65%) without requiring any sample pretreatment.
Subject(s)
Adenosine Triphosphate/blood , Fluorescent Dyes/chemistry , Humans , Hydrogen Bonding , Lactones/chemistry , Molecular Structure , Serine/chemistry , Sulfonamides/chemistry , Thiourea/chemistryABSTRACT
Chiral fluorescent chemosensors featuring macrocycles comprising BINOL auxiliary and an array of hydrogen bond donors were synthesized. To enhance fluorescence of the chemosensors, conjugated moieties were attached to the 3,3'-positions of the BINOL auxiliary. The resulting chemosensors recognize a number of carboxylates, namely, enantiomers of ibuprofen, ketoprofen, 2-phenylpropanoate, mandelate, and phenylalanine in a stereoselective fashion. Depending on the structure of the chemosensor, the presence of carboxylate yields fluorescence quenching or amplification. This information-rich signal can be used to determine the identity of the analyte including the sense of chirality. Quantitative experiments were performed aimed at analysis of enantiomeric excess of chiral carboxylates. The quantitative analysis of enantiomeric composition of ibuprofen, ketoprofen, and phenylalanine shows that the sensors correctly identify mixtures with varying enantiomeric excess and correctly predict the enantiomeric excess of unknown samples with error of prediction <1.6%.
ABSTRACT
Tri-serine tri-lactone based C3 symmetry fluorescent sensors were synthesized. Citrate is shown to bind to sensors, while displaying an increase in fluorescence intensity for the sensor with thiourea and a quenching for the sensor with sulfonamide. Information-rich responses of the sensors enable us to discriminate structurally similar anions, including mono-, di- and tri-carboxylates with 100% correct classification. A simple two-sensor array enables the determination of the concentration of citrate in urine without any sample preparation with high accuracy (error < 2%).
Subject(s)
Citric Acid/urine , Lactones/chemistry , Serine/chemistry , FluorescenceABSTRACT
Cinchona alkaloids (quinine, quinidine, cinchonine, cinchonidine) alkylated at N(1) with chloromethyl anthracene can serve as fluorescent sensors for chiral carboxylic acids. These cinchona ammonium salts are shown to bind chiral carboxylic acids while displaying an increase in fluorescence intensity that can be utilized in determination of enantiomeric excess (ee). Sensor arrays composed of four cinchona ammonium salts are used for quantitative analysis of ee in several non-steroidal anti-inflammatory drugs (NSAIDs), such as enantiomers of ibuprofen, ketoprofen, and naproxen.
Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/analysis , Carboxylic Acids/analysis , Carboxylic Acids/chemistry , Ibuprofen/analysis , Ketoprofen/analysis , Naproxen/analysis , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Crystallography, X-Ray , Fluorescence , Fluorescent Dyes/analysis , Fluorescent Dyes/chemistry , Ibuprofen/chemistry , Ketoprofen/chemistry , Models, Molecular , Molecular Structure , Naproxen/chemistry , StereoisomerismABSTRACT
One of the well-known strategies for anion sensing is an indicator (dye) displacement assay. However, the disadvantage of the dye displacement assays is the low sensitivity due to the excess of the dye used. To overcome this setback, we have developed an "Intramolecular Indicator Displacement Assay (IIDA)". The IIDAs comprise a receptor and a spacer with an attached anionic chromophore in a single-molecule assembly. In the resting state, the environment-sensitive anionic chromophore is bound by the receptor, while the anionic substrate competes for binding into the receptor. The photophysical properties of the dye exhibit change in fluorescence when displaced by anions, which results in cross-reactive response. To illustrate the concept, we have prepared IID sensors 1 and 2. Here, the characterization of sensors and microtiter arrays comprising the IIDA are reported. The microtiter array including IID sensors 1 and 2 is capable of recognizing biological phosphates in water. The utility of the IIDA approach is demonstrated on sensing of a phosphonate herbicide glyphosate and other biologically important anions such as pyrophosphate in the presence of interferent sodium chloride.
Subject(s)
Diphosphates/chemistry , Fluorescent Dyes/chemistry , Glycine/analogs & derivatives , Herbicides/chemistry , Anions , Chlorides/chemistry , Discriminant Analysis , Electrolytes , Glycine/chemistry , Magnetic Resonance Spectroscopy , Multivariate Analysis , Phosphates/chemistry , Polymers/chemistry , Sodium Chloride/chemistry , Water/chemistry , X-Ray Diffraction , GlyphosateABSTRACT
A supramolecular sensor array composed of two fluorescent cucurbit[n]uril-type receptors (probe 1 and probe 2) displaying complementary selectivities was tested for its ability to detect and quantify drug-related amines. The fluorimetric titration of the individual probes showed highly variable and cross-reactive analyte-dependent changes in fluorescence. An excellent ability to recognize a variety of analytes was demonstrated in qualitative as well as quantitative assays. Importantly, a successful quantitative analysis of several analytes of interest was achieved in mixtures and in human urine. The throughput and sensitivity surpass those of the current state-of-the-art methods that usually require analyte solid-phase extraction (SPE). These results open up the opportunity for new applications of cucurbit[n]uril-type receptors in sensing and pave the way for the development of simple high-throughput assays for various drugs in the near future.
Subject(s)
Chemistry Techniques, Analytical/instrumentation , Nonprescription Drugs/analysis , Substance-Related Disorders , Amines/analysis , Amines/chemistry , Amines/urine , Humans , Imidazoles/chemistry , Models, Molecular , Molecular Conformation , Nonprescription Drugs/chemistry , Time FactorsABSTRACT
OBJECTIVE: This study was designed to compare the results of the Modified Darn Repair through Lichtenstein procedure in inguinal hernias. MATERIALS AND METHODS: The study involved 322 patients with inguinal hernia, operated in General Surgery Departments of Gulhane Military Medical Academy and Sirnak Military Hospital between 1998 and 2004. The durations of operation time, hospitalization, and time to return to daily activities and postoperative complication and recurrence rates were evaluated. Lichtenstein procedure was applied on 170 patients (Group 1), and modified darn repair was applied on 152 patients (Group 2). RESULTS: The average follow-up period was 56 months. For the Lichtenstein procedure, the average duration of operation was 56 min; the average time to return to routine activities was 20 days. The number of patients with postoperative complications was 20 (11.7%), and the number of patients with recurrence was 1 (0.6%). For modified darn repair, the average duration of operation was 48 min; the time to return to daily activities was 20 days. The number of patients with postoperative complication was three (1.9%), and no recurrences were noted. The hospitalization time of the groups was similar. DISCUSSION: Modified darn repair is a reliable method for inguinal hernia repair with short hospitalization time, low rate of postoperative complications, and recurrence.
Subject(s)
Hernia, Inguinal/surgery , Adolescent , Adult , Aged , Female , Humans , Length of Stay , Male , Middle Aged , Postoperative Complications , Prospective Studies , Recurrence , Treatment OutcomeABSTRACT
The principal objectives of this study were to identify the main predictors of the length of postoperative hospital stay for patients undergoing appendectomy in a military training hospital in Turkey, to examine the effects of each significant predictor, and to justify to hospital health care managers the reasons why an increase in effective use of hospital utilization resources is needed and so important. This study gives the results of a 2-year retrospective study conducted at Gulhane Military Medical Academy between January 2003 and January 2005. The medical files of 417 patients undergoing appendectomy during this 2-year period were reviewed. A number of demographic and clinical patient characteristics were examined to determine their significance in lengthening the post-operative and total hospital stay. After taking all demographic and clinical patient characteristics into account, it was determined that those patients who were temporary or short-term service members and whose medical complications were more severe were more likely to stay in the hospital for longer periods. Despite its limitations, the study reveals that factors affecting variations in resource utilization can be minimized by following very simple administrative procedures. Furthermore, the results could increase awareness among hospital managers of the significant factors involved for health care providers in modifying their behavior concerning resource utilization decisions.
Subject(s)
Appendectomy , Appendicitis/surgery , Hospitals, Military/statistics & numerical data , Hospitals, Teaching/statistics & numerical data , Military Medicine , Treatment Outcome , Adult , Female , Health Resources/statistics & numerical data , Humans , Length of Stay , Male , Military Personnel/statistics & numerical data , Postoperative Care , Retrospective Studies , Turkey , Utilization ReviewABSTRACT
Selection of the most appropriate treatment to obtain the best results with the lowest rate of recurrence and minimal morbidity and mortality is mandatory for the management of hepatic hydatid disease. The surgical approach is the mainstay of treatment, and there has been a tendency toward laparoscopic surgery and, more recently, percutaneous treatment (PT), which has become increasingly popular with revolutions in techniques. We aimed to evaluate the results of current therapeutic methods in the context of a 10-year single-institution experience. Between 1992 and 2003, 355 patients with 510 hydatid cysts of the liver were treated by open operation, laparoscopic surgery, or PT. The series included 128 females and 227 males ranging in age from 10 years to 73 years. Preferred treatment modalities, perioperative complications, interventions, recurrences, and length of hospital stay were retrospectively analyzed. There were two postoperative deaths (1.08%) in the open surgery group. Biliary leakage was observed in 28 patients treated with open surgery, in 10 patients after PT, and in 2 after laparoscopic treatment. Recurrence rates were 16.2%, 3.3%, and 3.5% after open surgery, laparoscopic surgery, and percutaneous treatment, respectively. Characteristics of the cyst, presence of cystobiliary communications, and the availability of a multidisciplinary team are the factors that we believe directly affect the results. Radical surgery can be done safely for suitable cases; conventional procedures are associated with greater morbidity. Laparoscopic surgery seems effective and safe, with low morbidity and recurrence rates for type I-III cysts in accessible localizations. Our experience with PAIR (puncture, aspiration, injection, and reaspiration) and catheterization provides evidence that the procedure is an effective and safe option.
Subject(s)
Catheterization , Drainage , Echinococcosis, Hepatic/therapy , Hepatectomy , Laparoscopy , Adolescent , Adult , Aged , Albendazole/administration & dosage , Anthelmintics/administration & dosage , Child , Ethanol/administration & dosage , Female , Humans , Male , Middle Aged , Recurrence , Retrospective Studies , Solvents/administration & dosage , Treatment OutcomeABSTRACT
Basic pathological disorder in Hirschsprung's disease (HD) comes into being by the abnormal innervations of the aganglionic distal intestine. The nonserious forms of this congenital disease may reach the young by proceeding with chronic, obstinate constipation that does not respond to diet. Myectomy of the short segment of aganglionic part may provide diagnostic and therapeutic value. Between 1993 and 2003, anorectal posterior myectomy was performed in 19 patients diagnosed with HD. The mean age of patients was 23 years. Previous or concomitant anterior resection was added to the procedure in seven cases due to dolicomegacolon. In addition to the deficiency of anorectal inhibitor reflex (ARIR) among all patients, the frequency of defecation was 12.5 days (range, 6-30 days) before operation. Anorectal length before widening was an average of 5.5 cm (range, 2-8 cm). All pathologic specimens were found to be aganglionic. Postoperatively, the mean of first regular defecation interval was 1.5 days (range, 1-3 days). Involution of rectum was evaluated with a rectal examination and barium enema X-rays during follow-up. ARIR of patients also returned to normal. In conclusion, anorectal posterior myectomy is an effective operation in diagnosis and treatment of short-segment HD. Furthermore, colon resection annexed to this operation, in the condition of dolicomegacolon, is also used to remove obstinate constipation.
Subject(s)
Colectomy/methods , Hirschsprung Disease/surgery , Muscle, Smooth/surgery , Rectum/surgery , Adolescent , Adult , Female , Hirschsprung Disease/physiopathology , Humans , Male , Muscle, Smooth/innervation , Rectum/innervationABSTRACT
Anastomotic healing can deteriorate because of different local and systemic effects in cases of concomitant left colon and liver injuries. We evaluated the effects of portal triad occlusion (PTO) on bowel anastomosis after concomitant segmental left colonic resections achieved in rats. There were three separate groups of animals; each consisted of 20 Sprague-Dawley male rats weighing 250 +/- 20 g. In group I, left colonic segmental resection 1 cm in diameter and anastomosis were performed as controls. In group II, the same surgical procedure was done after 15 minutes of PTO followed by 30 minutes of reperfusion. In group III, PTO time was held at 30 minutes. The rats were killed at days 4 and 7 to evaluate anastomotic healing, histological changes, bursting pressures, and serum levels of malondialdehyde (MDA) and hydroxyproline. In group II, the bursting pressures of anastomosis on days 4 and 7 were similar to group I; these pressures were significantly lower in group III (P < 0.001), whereas the hydroxyproline levels in group II were lower than group I and group III levels (P < 0.002). There were histopathological changes that support the data found in groups II and III. Serum MDA levels in groups II and III were significantly higher than in group I (P < 0.001). We observed that serum MDA levels peaked at day 4 and gradually decreased with a statistically significant difference at day 7. In conclusion, there were no negative effects of PTO on colonic anastomosis in group II. But in group III, with longer occlusion times, anastomotic healing was impaired and the mortality rate was higher.