PubMed Health⌕ Search

Biomedical subjects

S Dighe

Publications and source records attributed to S Dighe.

12 recordsLinked to original sources
PubMed2007

Preoperative chemotherapy and the outcome of liver resection for colorectal metastases.

BACKGROUND: Neoadjuvant systemic chemotherapy is being increasingly used prior to liver resection for colorectal metastases. Oxaliplatin has been implicated in causing structural changes to the liver parenchyma, and such changes may increase the morbidity and mortality of surgery. PATIENTS AND METHODS: A retrospective study was undertaken of 101 consecutive patients who had undergone liver resection for colorectal metastases in two HPB centers. Preoperative demographic and premorbid data were gathered along with liver function tests and tumor markers. A subjective assessment of the surgical procedure was noted, and in-hospital morbidity and mortality were calculated. The effect of preoperative chemotherapy on short-term and long-term outcome was analyzed, and actuarial 1 and 3 year survival was determined. RESULTS: Patients who received neoadjuvant chemotherapy had a higher number of metastases (median 2, range 1-8 versus median 1, range 1-5; P = 0.019) and more had synchronous tumors (24 patients versus 8; P < 0.001). Overall morbidity was 37% and hospital mortality was 3.9%. Operative and in-hospital outcome was not influenced by chemotherapy. Long-term survival was worse in patients who had received preoperative chemotherapy (actuarial 3-year survival 62% versus 80%; P = 0.04). CONCLUSIONS: This study shows no evidence that neoadjuvant chemotherapy, and in particular oxaliplatin, increases the risk associated with liver resection for colorectal metastases. Long-term outcome is reduced in patients receiving preoperative chemotherapy, although they have more advanced disease.

Adult↗
PubMed1992

Influence of higher rates of agitation on release patterns of immediate-release drug products.

The dissolution procedure serves as a quality control test to assure batch-to-batch uniformity and bioequivalence of a product once the bioavailability of the product has been established. It can also be used to detect manufacturing and/or process variations that could reduce product bioavailability. Dissolution testing must be conducted at an appropriate agitation rate. Tests conducted at high agitation rates may lose the ability to differentiate between good and bad products. Although the effect of high agitation rates has been known for some time, several immediate-release drug products still have United States Pharmacopeia (USP) monograph dissolution procedures that require very high agitation rates. A systematic survey was conducted on marketed tablets of chloroquine phosphate, griseofulvin, hydroxychloroquine sulfate, isocarboxazide, primaquine phosphate, and sulfadiazine. Each of these products has a USP monograph requiring a dissolution test at a paddle speed of 100 rpm. To study the influence of agitation rate on the dissolution rate of these products, dissolution studies were conducted at paddle speeds of 50, 75, and 100 rpm with the USP apparatus 2 (paddle method). The dissolution rate increased with an increase in the agitation rate from 50 to 75 rpm. However, no significant increase in the dissolution rate was noted with an increase in the agitation rate from 75 to 100 rpm. The data support the position that the higher agitation rate of 100 rpm is not necessary for a quality control procedure or a compendial standard for the products tested.

Chloroquine↗
PubMed1980

Correlation of in vivo bioavailability of erythromycin stearate tablets with in vitro tests.

Correlations between the bioavailability parameters for erythromycin stearate tablets from five manufacturers and in vitro tests of these tablets were examined using forward (stepwise), multiple linear regression analysis. Bioavailability parameters were determined in clinical studies employing a balanced, incomplete block design. In vitro tests used disintegration, dissolution, and dissolution/dialysis as the independent variables in regression equations. Significant correlations were found between linear combinations of these parameters and the time of peak and the peak serum levels. The inclusion of an in vitro disintegration test to describe peak serum levels of erythromycin is noteworthy since it has been suggested that disintegration tests are of less value than dissolution techniques employed in the present investigation may be useful for selection of appropriate physicochemical tests for continued monitoring of the bioavailability of erythromycin stearate tablets.

Biological Availability↗
PubMed1979

Bioavailability of imipramine tablets relative to a stable isotope-labeled internal standard: increasing the power of bioavailability tests.

A new methodology for comparative bioavailability testing is described in which each drug formulation is compared with a stable isotope-labeled variant of the drug that is consumed orally in solution at the same time the tested formulation is ingested. The methodology is used to determine the comparative bioavailabilities of two commercially available brands of imipramine hydrochloride. The power of the new methodology to detect differences between drug formulations, when, in fact, such differences exist, is shown to be superior to that of conventional bioavailability tests.

Adolescent↗
PubMed1973

The effect of keto-analogues of essential amino acids in severe chronic uremia.

Alpha keto-analogues of valine, leucine, isoleucine, methionine, phenylalanine, and (in one instance) tryptophan and histidine, along with the remaining essential amino acids, were administered orally to 10 patients with severe chronic uremia fed a diet low in protein but adequate in calories. Ketoacid dosage varied from 6 to 14 g daily, as sodium or calcium salts. Net nitrogen intake, calculated as intake minus urinary protein nitrogen, averaged 1.8 g/day. The urea space was either estimated or measured with [(14)C]urea and daily changes in the body urea pool were calculated. Urea appearance was measured as the sum of urea excretion and the change in urea pool. If these ketoacids were converted to amino acids and utilized for protein synthesis, a fall in urea nitrogen appearance should occur. In five subjects, ketoacids were given for 15-18 days and then withdrawn. Urea nitrogen appearance increased 1.55 g/day on withdrawing ketoacids, and corrected nitrogen balance decreased by 1.73 g/day. In two other subjects ketoacid administration was followed, on two occasions each, by a period of administration of nine essential amino acids. In three of these four instances, urea appearance rose significantly with amino acids. In four patients studied at high blood urea levels, ketoacid treatment was relatively ineffective; two of these patients responded more favorably when studied again after peritoneal dialysis. One of these improved enough clinically to be managed as an out-patient for short intervals, despite virtual anuria. No accumulation of ketoacids in plasma or urine could be detected, and no toxicity was identified.

Adult↗
PubMedDate not supplied

Analytical methods validation: bioavailability, bioequivalence and pharmacokinetic studies. Conference report.

This is a summary report of the conference on Analytical Methods Validation: Bioavailability, Bioequivalence and Pharmacokinetic Studies. The conference was held from December 3 to 5, 1990 in the Washington, DC area and was sponsored by the American Association of Pharmaceutical Scientists, US Food and Drug Administration, Federation International Pharmaceutique, Health Protection Branch (Canada) and Association of Official Analytical Chemists. The purpose of the report is to represent our assessment of the major agreements and issues discussed at the conference. The report is also intended to provide guiding principles for validation of analytical methods employed in bioavailability, bioequivalence and pharmacokinetic studies in man and animals. The objectives of the conference were: 1. To reach a consensus on what should be required in analytical methods validation and the procedures to establish validation; 2. To determine processes of application of the validation procedures in the bioavailability, bioequivalence and pharmacokinetic studies; 3. To develop a report on analytical methods validation (which may be referred to in developing future formal guidelines). Acceptable standards for documenting and validating analytical methods with regard to processes, parameters or data treatments were discussed because of their importance in assessment of pharmacokinetic, bioavailability and bioequivalence studies. Other topics which were considered essential in the conduct of pharmacokinetic studies or in establishing bioequivalency criteria, including measurement of drug metabolites and stereoselective determinations, were also deliberated.

Biological Availability↗
PubMedDate not supplied

Invasive adenocarcinoma of the vagina following surgery for adenocarcinoma in situ of the cervix--recurrence or implantation?

A 51-year-old woman underwent cervical conization for severe glandular abnormal cells. Histology noted adenocarcinoma in situ (AIS) with incomplete excision margins. Four months later, hysterectomy revealed no residual disease. Six months subsequently she developed invasive adenocarcinoma of the upper vagina. This report documents the unusual behavior of AIS and its management difficulties.

Adenocarcinoma↗