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Kwong-Leung Yu

Publications and source records attributed to Kwong-Leung Yu.

9 recordsLinked to original sources
PubMed2006

Age-related changes in oxytocin-, arginine vasopressin- and nitric oxide synthase-expressing neurons in the supraoptic nucleus of the rat.

Many histochemical investigations indicated that the oxytocin (OXY), the arginine vasopressin (AVP) and the nitric oxide synthase (NOS) have been synthesized in the supraoptic nucleus (SON) neurons. The objective of this study was to examine the age-related expression of the OXY, the AVP and the NOS in the SON of the young adult (2-month-old) and the aged (24-month-old) rats. The histochemistry for reduced nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d; marker for the NOS) and the double labeling histochemistry for the OXY/NADPH-d or the AVP/NADPH-d were employed, and the quantitative analysis was performed with a computer-assisted image processing system. In comparison of the young adult and the aged group, the cell number, the cell size and the reactive density of the NOS-expressing neurons showed a significant increase along with age, and these evidences suggested the age-related increase of the nitric oxide (NO) production. The age-related significant increase was not detected in the number of the OXY/NOS-expressing neurons in the dorsal part, but was detected in the number of the AVP/NOS-expressing neurons in the ventral part. Based on our histochemical findings and reports demonstrated by other authors, we attempted to discuss the physiological role of NOS for the secretion of posterior pituitary hormones along with age.

Aging↗
PubMed2004

Punctate midline myelotomy for intractable visceral pain caused by hepatobiliary or pancreatic cancer.

The purpose of this study was to demonstrate the existence of a newly recognized midline posterior column pathway that mediates the perception of visceral pain resulting from hepatobiliary or pancreatic cancer. A punctate midline myelotomy (PMM) of T(3) level was performed in 6 patients who experienced severe visceral pain caused by hepatobiliary or pancreatic cancer. Preoperatively, the pain was refractory to strong opioids. Clinical efficacy of PMM was evaluated by comparing patient pain rating on a visual analogue scale. Follow-up periods ranged from 2-18 weeks after operation. All 6 patients had immediate pain relief after operation. Although the pain recurred from 2-12 weeks later in 3 patients, the severity of recurrent cancer pain markedly decreased. No adverse neurological sequelae were observed. Our results of high thoracic PMM offer clinical support for the concept that neurosurgical interruption of midline visceral pain pathway can effectively control severe visceral pain without causing adverse neurological sequelae in patients with hepatobiliary or pancreatic cancer.

Aged↗
PubMed2004

Total intravenous anesthesia for repair of congenitral diaphragmatic hernia: a case report.

Congenital diaphragmatic hernia is a cardiopulmonary anomaly that causes severe respiratory disorder. Traditionally, inhalational anesthetics with mechanical hyperventilation, opioids, and muscle relaxants are used in anesthesia for repair surgery. In this case, we used total intravenous anesthesia combined with high-frequency oscillatory ventilation and inhaled nitric oxide for surgical repair of the diaphragm. After surgery, the patient recovered well and was discharged from hospital 1 month later.

Administration, Inhalation↗
PubMed2004

Urgosedin inhibits hypotension, hypoglycemia, and pro-inflammatory mediators induced by lipopolysaccharide.

Urgosedin is a newly synthesized compound especially with serotonergic and alpha-adrenergic blocking actions. In rat isolated thoracic aorta, urgosedin competitively antagonized norepinephrine-, clonidine-, and serotonin-induced vasocontractions in a concentration-dependent manner. In radioligand binding experiments, urgosedin had significant binding affinities on alpha1/alpha2, 5-HT1A, 5-HT1B and 5-HT2A receptors. Intravenous injection of lipopolysaccharide (LPS) produced a biphasic hypotension in normotensive rats. Although intravenous injection of urgosedin caused minor depressor actions in the normotensive Wistar rat, urgosedin significantly attenuated the secondary prolonged hypotension produced by LPS. The plasma levels of cytokines (IL-1beta, IL-6, TNF-alpha, and IFN-gamma) and hypoglycemia induced by LPS were also reduced by urgosedin. Moreover, the acute survival rates (350 minutes) of endotoxic shock increased from 0% (LPS group) to 100% in the groups pretreated with urgosedin. In RAW264.7 cells, urgosedin inhibited LPS-induced inducible nitric oxide synthase (iNOS) expression. In conclusion, our data suggest that urgosedin was a newly potent serotonergic and mild alpha-adrenergic blocking agent. Its prevention of LPS-induced hypotension and hypoglycemia might partially mediate through its inhibition activities on the iNOS expression and cytokines formation. Urgosedin might be an effective pharmacological agent against LPS-induced hypotension, hypoglycemia, and the formation of pro-inflammatory mediators.

Administration, Oral↗
PubMed2003

Ropivacane 0.1 % with or without fentanyl for epidural postoperative analgesia: a randomized, double-blind comparison.

Epidural analgesia is often considered optimal postoperative analgesia for certain surgical procedures. Ropivacaine is a new local anesthetic that is less toxic than its homologue, bupivacaine. Epidural infusions usually comprise a local anesthetic, an opioid, or a combination of the two to improve analgesic efficacy and reduce unwanted side effects. All 210 patients undergoing lower abdominal or lower extremity surgery received epidural analgesia infusions at 7 mL/hour, 105 with 0.1% ropivacaine and 105 with 0.1% ropivacaine plus 1 microg/mL fentanyl. Pain score and side effects (hypotension, nausea, vomiting, pruritus, paresthesia, urinary retention and motor block) were measured at 0, 0.5, 1, 3, 6, 12, and 24 hours. There was no statistical difference in patient profile between the groups. Pain relief scores were similar in the two groups in the first hour after the drugs were given. However, pain relief was significantly better in the ropivacaine/fentanyl group after the first hour and this difference lasted for the remaining time. There was no significant difference in adverse events between the two groups during 24 hours of assessment. In conclusion, the quality of analgesia was significantly improved by the addition of fentanyl 1 microg/mL to ropivacaine.

Adult↗
PubMed2003

Spinal process landmark as a predicting factor for difficult epidural block: a prospective study in Taiwanese patients.

Although epidural anesthesia is a common practice in neuraxial blockade, difficult access to the epidural space is a frequent problem in operating theaters. We designed this study of epidural blocks to determine if the spinal landmark grading system is valuable in predicting a difficult epidural block. Before the epidural block, we collected the following data: demographics, body habitus (normal, thin, obese, pregnant), spinal anatomy (normal, deformed), spinal level (lumbar, thoracic), and spinal landmark grade (grade 1: spinous processes visible; grade 2: spinous processes not seen but easily palpated; grade 3: spinous processes not seen and not palpated but the interval between them is palpated as a low landmark under the thumb; grade 4: other). We performed all 848 epidural blocks initially using a midline approach and an 18-gauge Touhy needle. We evaluated the technical difficulty of the epidural block using three methods: whether the epidural block was accomplished at the spinal level (first-level success); the total number of attempts at skin puncture (attempts-S); and total number of attempts to change ligament puncture direction (attempts-L) required to complete the epidural block. Of all examined factors, spinal landmark grade correlated best with technical difficulty as measured by all three methods. Deformed spinal anatomy and body habitus both correlated with difficulty, merely from the total numbers of attempts (attempts-S and attempts-L). Thoracic epidurals were more difficult than lumbar epidurals by all three measures of difficulty. We concluded that this spinal landmark grading system is valuable in predicting a difficult epidural block and advocate its use as a predictor by anesthesiologists.

Adolescent↗
PubMed2003

Epidural ropivacaine for postoperative analgesia in Taiwanese patients.

BACKGROUND: Ropivacaine is the latest long-acting amide local anesthetic. As it is less cardiovasculotoxic and neurotoxic than bupivacaine it is an attractive anesthetic agent used in clinical anesthesia and postoperative analgesia. This study was undertaken to seek for a suitable dosage of ropivacaine in postoperative analgesia for Taiwanese patients whose average physicality is not entirely compatible with the pharmacopeially recommended dosage for western people. METHODS: For assessment of epidural ropivacaine for postoperative analgesia 105 adult patients were enrolled and randomly allotted to three groups. Patients in Group A were given epidurally 0.15% ropivacaine, while those in Group B and Group C were given 0.125% and 0.10% ropivacaine respectively. Pain was evaluated with visual analogue scale (VAS) and modified Bromage scale, and adverse effects were recorded at the designated points of time during the postoperative 24-hour period. RESULTS: The demographic profiles were comparable among three groups. In VAS score, Group A (3.20 +/- 0.47) and B (3.11 +/- 0.41) did not differ much, while Group C (3.97 +/- 0.71) the score was signally higher than Group A and Group B (P < 0.05). Adverse effects, such as paraesthesia, nausea and urinary retention were observed more in Group A. CONCLUSIONS: From the results of this study, we are of the opinion that 0.125% ropivacaine could provide a postoperative analgesia in Taiwanese patients to their satisfaction with less adverse effects.

Adult↗
PubMed2002

An alternative technique for accurate placement of central venous catheter tips.

For intravenous electrocardiography (IVECG), a wire stylet is usually utilized as the exploring probe to correctly position the central venous catheter. We present an alternative technique using the transduction probe connected to the original right arm lead of the ECG monitor to accurately position the central venous catheter. We compared the efficacy and quality of the IVECG signals of the two techniques. Sixty patients were randomly enrolled into two groups. In group G, the IVECG signal was conducted from the guide wire to identify the correct catheter tip position. In group T, the IVECG signal was conducted from the transduction probe to ascertain the tip position. The quality of IVECG signals, which included baseline drift, P-wave pattern, and QRS wave pattern, were assessed for 10 seconds. There was no obvious difference between the groups for catheter tip placement time or measured optimal catheter length. During manipulation, the incidence of cardiac dysrhythmia was higher in group G than in group T, but the difference was not significantly different (p = 0.09). Satisfactory IVECG signal quality was observed in 26 of the 30 patients in group G and in 27 of the 30 patients in group T. We conclude that the transduction probe can effectively conduct IVECG signals with no specific additional equipment required. It is an alternative technique for accurate placement of central venous catheter tips during IVECG.

Adult↗