Biomedical subjects

Kuo-Hsin Chen

Publications and source records attributed to Kuo-Hsin Chen.

9 recordsLinked to original sources

PubMed2006

Impact of previous abdominal surgery on laparoscopic appendectomy for acute appendicitis.

BACKGROUND: Laparoscopic appendectomy is one of the most commonly performed laparoscopic procedures. Impact of previous abdominal surgery on laparoscopic appendectomy has not been previously reported. METHODS: From January 2001 to December 2005, 2029 patients with clinically suspected acute appendicitis underwent laparoscopic surgery in our hospital. Of these, 234 patients (11.5%) were found to have other pathology by intraoperative or histologic findings and were excluded from the study. The 1795 patients who underwent laparoscopic appendectomy for acute appendicitis were divided into three groups: group 1, patients without a history of previous abdominal surgery (n = 1652, 92%); group 2, patients with a history of upper abdominal surgery (n = 20, 1.1%); group 3, patients with a history of lower abdominal surgery (n = 123, 6.8%). Data were collected retrospectively by chart review and analyzed for conversion rate, operative time, intraoperative and postoperative complications, and hospital stay. RESULTS: Of the 1795 patients, 13 (0.7%) were converted to open appendectomy because of technical difficulty. Overall mean operative time was 57.2 (range, 20-225) min. There was no mortality or intraoperative complications. Overall postoperative complication rate was 10.7% (n = 193): rate of surgical wound infection was 8.2% (n = 147), surgical wound seroma 1.3% (n = 24), and intra-abdominal abscess 0.8% (n = 14). Overall postoperative hospital stay averaged 3.2 (range, 0-39) days. There were no significant differences between the three groups regarding the conversion rate (0.8% vs. 0% vs. 0%, p = 0.567), operative time (57.3 vs. 55.8 vs. 56.9 min, p = 0.962), postoperative complication rates (10.7 vs. 10 vs. 12.2%, p = 0.863), and hospital stay (3.2 vs. 3.6 vs. 3.1 days, p = 0.673). CONCLUSIONS: Previous abdominal surgery, whether upper or lower abdominal, has no significant impact on laparoscopic appendectomy for acute appendicitis.

Acute Disease↗

PubMed2006

Laparoscopic versus open appendectomy for perforated appendicitis.

The role of laparoscopic appendectomy (LA) for perforated appendicitis is under investigation. A retrospective study was conducted to compare the outcomes of laparoscopic versus open appendectomy (OA) for perforated appendicitis. From January 2001 through December 2003, 229 patients with perforated appendicitis were treated at Far-Eastern Memorial Hospital. LA was successfully completed in 91 of 99 patients. OA was performed in 130 patients. Operation time was longer in the LA group (mean +/- SD = 96.1 +/- 43.1 vs. 67.8 +/- 32.2 minutes, P < 0.01). Return of oral intake was faster in the LA group (3.2 +/- 2.4 vs. 5.0 +/- 7.0 days, P < 0.01). The intravenous antibiotic usage period was shorter in the LA group (4.4 +/- 2.8 vs. 6.3 +/- 7.1 days, P < 0.01). The postoperative wound infection rates were 15.2 % (LA group) and 30.7% (OA group). The overall infectious complication rates were 19% in the LA group and 37% in the OA group (P < 0.01). Hospital stay days were shorter for the LA group (6.3 +/- 2.9 vs. 9.3 +/- 8.6 days, P < 0.01). Our results indicated that laparoscopic appendectomy is a safe and effective procedure for treating patients with perforated appendicitis.

Adult↗

PubMed2006

Laparoscopic diagnosis and treatment of small bowel obstruction caused by postoperative intussusception.

Small bowel obstruction is a common problem, especially for patients who have had previous abdominal surgery possibly complicated by postoperative adhesions. In contrast to adhesions, postoperative intussusception is an unusual cause of small bowel obstruction. We report a case of small bowel obstruction that occurred one month after antrectomy for duodenal ulcer with massive bleeding. Laparoscopic surgery was attempted after conservative treatment failed. A segment of jejunojejunal intussusception about 50 cm below the ligament of Treitz was identified and laparoscopic reduction of the intussusception was performed. The patient had an uneventful postoperative course and remained asymptomatic at 10-month follow-up. Although not frequently encountered, postoperative intussusception should be considered a possible etiology in patients with postoperative small bowel obstruction. In experienced hands, the laparoscopic approach offers a feasible option for correct diagnosis and appropriate treatment in this situation.

Adult↗

PubMed2005

Replacement of Phe6, Phe7, and Phe11 of D-Trp8-somatostatin-14 with L-pyrazinylalanine. Predicted and observed effects on binding affinities at hSST2 and hSST4. An unexpected effect of the chirality of Trp8 on NMR spectra in methanol.

An alanine scan performed in the 1970s suggested that Phe(6) and Phe(11) are required for the binding of somatostatin (SRIF-14). Molecular modeling studies and replacement of Phe(6) and Phe(11) with a cystine bridge affording ligands with the retention of high biological activity, however, led to the alternate conclusion that Phe(6) and Phe(11) stabilize the bioactive conformation of SRIF-14. Subsequent studies revealed that Phe(11) shields Phe(6) in a "herringbone" arrangement. More recently, a report from this laboratory demonstrated that Spartan 3-21G MO calculations can be invaluable in explaining SARs in medicinal chemistry. For example, the ability of benzene and indole rings to bind the Trp(8) binding pocket for SRIF-14 and the inability of pyrazine to do so was explained through differences in electrostatic potentials. To investigate the role of Phe(6) and Phe(11) more fully, we report here the synthesis of two analogues of D-Trp(8)-SRIF in which Phe(6) and Phe(11) were replaced by the pryazinylalanine congeners, respectively. The NMR spectra in D(2)O and the K(i)s fully support the proposition that Phe(11) stabilizes the bioactive conformation through pi-bonding or aromatic edge-to-face interaction and that pyrazinylalanine(6) can be shielded by Phe(11). The data also show unexpectedly that Phe(6), via the pi-bond, interacts with the receptor, consistent with the original interpretation of the alanine scan. Heretofore it had only been known that Lys(9) interacts with an aspartate anion of the receptor. These conclusions are supported by recent studies of Lewis et al. on the effects on K(i)s of Ala(6)-SRIF-14-amide at the five receptor subtargets. We also found that pyrazinylalanine(7)-D-Trp(8)-SRIF-14 does not bind, suggesting a repulsive interaction with the receptor. Taken together, our results not only validate predictions based on Spartan 3-21G MO analysis but also provide valuable information about the nature of the receptor interaction at the molecular level. Finally, the chirality of Trp(8) was unexpectedly found to have a striking effect on NMR spectra in methanol, especially at lower temperatures.

Alanine↗

PubMed2005

Design, synthesis, and binding affinities of pyrrolinone-based somatostatin mimetics.

[structure: see text] Tetrapyrrolinone somatostatin (SRIF) mimetics (cf. 1), based on a heterochiral (D,L-mixed) pyrrolinone scaffold, were designed, synthesized, and evaluated for biological activity. The iterative synthetic sequence, incorporating the requisite functionalized coded and noncoded amino acid side chains, comprised a longest linear synthetic sequence of 23 steps. Binding affinities at two somatostatin receptor subtypes (hsst 4 and 5) reveal micromolar activity, demonstrating that the d,l-mixed pyrrolinone scaffold can be employed to generate functional mimetics of peptide beta-turns.

Amino Acids↗

PubMed2005

Intramural gallbladder hematoma mimicking gallbladder neoplasm in a 33-year-old male.

We report a case of intramural gallbladder hematoma mimicking gallbladder neoplasm in a 33-year-old male; bleeding was confined to the gallbladder wall without rupture into the lumen. The patient presented with sudden onset of right upper quadrant pain, with no history of abdominal trauma. The abdomen was soft, with mild tenderness over the right upper quadrant, and a positive Murphy's sign. Abdominal sonography, computed tomography, and endoscopic retrograde cholangiopancreatography all revealed the presence of a mass lesion in the gallbladder wall. Thus, a gallbladder tumor was highly suspected. Laparoscopic cholecystectomy was performed, and intramural hematoma was found intraoperatively. The cause of intramural hemorrhage was obscure.

Abdomen↗

PubMed2005

Laparoscopic appendectomy in pregnancy.

BACKGROUND: Laparoscopic appendectomy (LA) is a safe, effective, and beneficial procedure for the treatment of acute appendicitis. However, limited data are available regarding the safety and feasibility of LA during pregnancy. METHODS: Between January 2001 and August 2004, 1235 patients with clinically suspected appendicitis underwent laparoscopic surgery at our hospital. Eleven patients (0.9%) were pregnant women (mean age, 25 years; age range, 19-37 years; range of gestational age, 4-30 weeks). Clinical data collected retrospectively included demographic information; preoperative, procedural, and postoperative information; and outcome of the pregnancy. RESULTS: All 11 pregnant women underwent laparoscopic surgery without need of conversion. Ten patients underwent LA and were found to have acute appendicitis on histologic analysis. One patient had torsion of the right fallopian tube and a healthy-looking appendix; she underwent detorsion of the fallopian tube and incidental appendectomy. Mean operative time was 50.5 minutes (range, 20-135 minutes). Length of postoperative hospital stay averaged 4.2 days (range, 1-11 days). One patient had a surgical wound infection, which was managed conservatively. Mean follow-up period was 14 months (range, 2-46 months). Seven pregnant women delivered healthy term infants, 2 had planned abortions, and 1 experienced fetal loss due to uterine infection and premature contractions 1 month after LA. Another patient had normal results at prenatal examination. CONCLUSION: Our data support the accumulating evidence that LA is a safe and feasible procedure for the treatment of acute appendicitis in all trimesters of pregnancy. Close maternal and fetal monitoring is essential during and after the operation.

Adult↗

PubMed2005

Laparoscopic diagnosis and treatment of acute small bowel obstruction resulting from a congenital band.

Acute small bowel obstruction is a common problem, especially for those patients with previous abdominal surgery that can cause postoperative adhesions. Acute, non-postoperative small bowel obstruction is less common and has various etiologies. We report a case of acute small bowel obstruction without previous abdominal surgery. The patient underwent laparoscopic exploration, and a congenital band was found to cause direct compression of the ileum and entrapment of a segment of bowel loop. There was evidence of bowel strangulation. The color and peristalsis of the entrapped bowel loop recovered gradually after division of the band, and segmental bowel resection was avoided. He has remained asymptomatic since the procedure. We suggest early and aggressive surgical intervention for patients with acute, non-postoperative small bowel obstruction to avoid possible complications of bowel strangulation and gangrene. A laparoscopic approach may be a safe, feasible, and favorable option for correct diagnosis and appropriate treatment in this situation.

Acute Disease↗

PubMed2005

Effects of calcineurin inhibitors on sirolimus pharmacokinetics during staggered administration in renal transplant recipients.

STUDY OBJECTIVE: To compare the effects of different calcineurin inhibitors on sirolimus pharmacokinetics during long-term, staggered administration in kidney transplant recipients. Design. Randomized, open-label, parallel-group trial. SETTING: A medical center and one of its teaching hospitals in Taiwan. PATIENTS: Twenty-two de novo kidney transplant recipients. INTERVENTION: Patients received cyclosporine microemulsion or tacrolimus capsules twice/day in combination with once-daily sirolimus solution and corticosteroids. Sirolimus was administered 6 hours after the morning dose of cyclosporine or tacrolimus. After receiving a 6-mg loading dose of sirolimus, participants received sirolimus 2 mg/day for at least 7 days. Neither the cyclosporine nor the tacrolimus dosage was adjusted for at least 3 days before and during blood sampling for pharmacokinetic profiling. MEASUREMENTS AND MAIN RESULTS: One patient dropped out because of trimethoprim-sulfamethoxazole-related hepatotoxicity. We observed no differences between the two patient groups in terms of their demographic data, renal and liver function, or dosage of sirolimus during the study. During multiple-dose administration, the area under the whole-blood concentration-time curve and the peak and trough concentrations of sirolimus in the cyclosporine group were, respectively, 1.46 (95% confidence interval [CI] 1.21-1.71), 1.42 (95% CI 1.08-1.76), and 1.42 (95% CI 1.09-1.76) times higher than those of the tacrolimus group, even though sirolimus was administered 6 hours after the other agents. CONCLUSION: Sirolimus pharmacokinetics may change significantly when calcineurin inhibitors are switched, even with staggered administration, which may not completely prevent a drug interaction between cyclosporine and sirolimus solution.

Adult↗