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H R Lee

Publications and source records attributed to H R Lee.

68 records · Page 4Linked to original sources
PubMed1983

The measurement of free nitrendipine in human serum by an equilibrium dialysis - radioreceptor assay.

A radioreceptor assay using [3H]nitrendipine and rat cerebral cortical membranes, in conjunction with equilibrium dialysis, measures the unbound (free) level of nitrendipine in human sera. The sensitivity of the assay is 0.1-0.2 picomoles/ml and is linear from 4 X 10(-11) to 4 X 10(-9) M nitrendipine. Other dihydropyridine calcium channel antagonists may be measured using this assay if these compounds are used to generate the standard curve. Blank serum interferes with specific [3H]nitrendipine binding (24 percent inhibition per 20 microliter serum) whereas serum dialysates do not. Total serum nitrendipine levels may be measured, but the sensitivity of the assay is decreased due to interference by serum. Nitrendipine is highly protein bound in serum (93 - 99 percent). This protein binding is essentially unchanged over a serum concentration from 1 to 100 ng/ml. This assay is suitable for pharmacokinetic and pharmacodynamic studies.

Animals↗
PubMed1983

Venous return in hemorrhagic shock after application of military anti-shock trousers.

UNLABELLED: The effect of Military Anti-Shock Trousers (MAST) on inferior vena cava blood flow was studied during graded hypovolemia using a pump reservoir system and an in-line electromagnetic flowprobe. During hemorrhagic shock MAST inflation increased cardiac output 25.4% ( CONTROL: 0.92 +/- 0.09 l/min) and arterial pressure 50% ( CONTROL: 60 +/- 2 mmHg). The so-called "autotransfusion" effect due to blood displacement from the lower part of the body into the central circulation was found to be only 4.3 +/- 0.6 ml/kg, a volume much less than previously estimated in the literature. We conclude that MAST inflation reliably improves cardiac output and systemic blood pressure above the diaphragm in dogs subjected to hemorrhagic shock. This effect is mainly due to a diversion of the cardiac output to the upper half of the body due to impedance of flow to the abdomen and lower extremities, rather than to a significant volume shift constituting an autotransfusion of blood from the lower part of the body.

Animals↗
PubMed1981

MAST augmentation of external cardiac compression: role of changing intrapleural pressure.

Ventricular fibrillation was induced in nine dogs weighing 18 to 22 kg. CPR was performed with a mechanical chest compressor. Mean carotid flow during CPR was 7.9 +/- 1.5 ml/min. After MAST inflation to 100 mm Hg, the flow increased to 15.7 +/- 3.7 ml/min. Intrathoracic aortic systolic pressure was also significantly increased from 65 +/- 7 to 73 +/- 8 mm Hg. When the thorax was vented with chest tubes bilaterally, no change in carotid flow or arterial pressure was noted on closing or opening the chest tubes. One liver laceration and two gallbladder contusions were noted at autopsy. MAST inflation apparently augments carotid flow an systolic pressure. Variations in intrapleural pressure do not seem to have a significant influence on CPR.

Animals↗
PubMedDate not supplied

Perioperative blood transfusions and prognosis in patients with curatively resected locally advanced gastric cancer.

Several reports have demonstrated an adverse effect of perioperative blood transfusions on the survival of patients with various solid tumors treated surgically. We retrospectively investigated the relationship between perioperative blood transfusions and the survival of 501 patients who underwent radical subtotal gastrectomy for locally advanced gastric cancer (stage II-IIIB) from January 1984 to December 1989. Three hundred and fifty-two patients (70.3%) received blood transfusions within the perioperative period. The transfused group included patients with tumors of larger size (5.1 vs. 4.4 cm, p = 0.001) and more advanced stage (stage IIIB: 27.6 vs. 10.7%, p = 0.0001) than the nontransfused group. Although the 5-year overall survival rate was significantly lower (52.9 vs. 66.7%, p = 0.026) in the transfused patients than the nontransfused, subgroup analysis according to the pathologic stage showed no statistically significant difference in survival in each stage between the two groups. In conclusion, we could not find any causal relationships between transfusion and prognosis in patients with curatively resected locally advanced gastric cancer. Circumstances such as advanced stage necessitating transfusions may be more important prognostic factors.

Blood Transfusion↗
PubMedDate not supplied

Overexpression of c-ErbB-2 protein in gastric cancer by immunohistochemical stain.

An immunohistochemical stain to the c-ErbB-2 protein was performed in 225 paraffin-embedded tissue blocks from patients with locally advanced gastric cancer who underwent curative resection. The overexpression of the c-ErbB-2 protein was observed in 27.4% of the patients. The c-ErbB-2 positivity showed a statistically significant correlation with nodal status and stage. The patients with an overexpression of the c-ErbB-2 protein had a tendency to a shorter survival than those without, but it was not statistically significant (p = 0.08). The 5-year survival rate after surgery was 54% in the negative staining group to the c-ErbB-2 protein and 49% in the positive staining group. This suggests that the c-ErbB-2 protein has a possible role in lymph node metastasis. Therefore overexpression of the c-ErbB-2 protein is a useful indicator of disease progression in gastric carcinoma patients who received curative surgery.

Adult↗
PubMedDate not supplied

Relationship between p53 overexpression and gastric cancer progression.

The relationship between p53 overexpression and clinicopathologic variables in gastric cancer was evaluated using 304 paraffin-embedded gastric tumor tissues. DO7, a murine monoclonal antiserum to p53 protein, was used for the immunohistochemical analysis. Positive staining was found in 129 tumors (42.2% of all tumors). Overexpression of p53 was not associated with sex, location of the tumor in the stomach or the type of Borrman's tumor. The overexpression rate of p53 protein was 30.4% (28/92) in stage II and 47.6% (101/212) in stage III (p = 0.007). While there was no significant association between p53 protein accumulation and T stage, there was a significant association with N stage, i.e. p53 overexpression was 27.4% (17/62) in the node-negative group and 46.3% (112/242) in the node-positive group (p = 0.011). In 79 patients, in whom corresponding primary gastric tumor and regional lymph node metastases were available, overexpression was found in 34 (43%) primary tumors and in 38 (48.1%) node samples, with a concordance rate of 67.1% in terms of p53 expression. Mean numbers of regional lymph node involvement by the tumor were 6.1 in the group with p53 overexpression and 5.2 in the group showing no immunoreactivity (p = 0.051). These findings suggest that p53 overexpression is related to gastric cancer progression and that immunoreactivity in the metastatic lymph nodes show the dependency on p53 expression in the primary tumor.

Adenocarcinoma↗
PubMedDate not supplied

OKT3 monoclonal antibody given for ten versus fourteen days as immunosuppressive prophylaxis in heart transplantation.

We have previously reported that murine antihuman monoclonal antibody OKT3 (Orthoclone OKT3) given for 14 days after heart transplantation is effective as immunosuppressive prophylaxis. The optimal protocol for OKT3 prophylaxis in heart transplantation is unknown, particularly the duration of OKT3 therapy. We conducted a consecutively allocated overlapping 6-month study with 68 heart transplant patients, comparing 14-day OKT3 (n = 34) to 10-day OKT3 treatment (n = 34). Both protocols included OKT3 given beginning 24 to 48 hours after operation, cyclosporine beginning on postoperative day 3, low-dosage steroids and azathioprine to prevent antibody production to OKT3, and a steroid pulse plus randomization to plus or minus vincristine after stopping OKT3. Pretransplant characteristics including age, sex, cause of congestive heart failure, and absence of positive pretransplant crossmatch were similar between the two groups. Although the infection rate was not significantly different between the two groups and mortality (one patient in each group) did not differ, 14-day prophylaxis decreased the number of treated rejection episodes per patient for the 6-month study (1.59 +/- 0.18 versus 2.24 +/- 0.19, p = 0.016). A 14-day course of OKT3 also decreased the risk of rejection during the 6-month follow-up period (p less than 0.05). In addition to having a decreased number of rejection episodes, patients in the 14-day protocol were also more likely to be withdrawn from maintenance steroids (79% versus 53%, p = 0.02). In conclusion, a measurable dose response efficacy can be demonstrated for 14-day versus 10-day OKT3 prophylaxis.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗
PubMedDate not supplied

Increased cardiac allograft rejection in female heart transplant recipients.

To assess differences between male and female recipients after heart transplantation, we retrospectively reviewed 140 consecutive heart transplant recipients (119 males and 21 females) with regard to sex and characteristics before and after transplantation. Before transplantation, fewer female recipients had heart failure on the basis of coronary artery disease (14% versus 56%, p = 0.001), and more females required inotropic agents (71% versus 38%, p = 0.007). Although average follow-up (for females 430 +/- 73 days, range 12 to 1097 days; for males 412 +/- 27 days, range 1 day to 1103 days, mean +/- standard error of the mean), mortality (one female and nine males), and proportion of recipients with infectious complications (48% females and 52% males) did not differ between the groups, female recipients manifested a higher incidence of rejection during the first 4 months (2.39 +/- 0.27 episodes versus 1.67 +/- 0.11 episodes, p = 0.010) and during follow-up (3.24 +/- 0.44 episodes versus 2.20 +/- 0.21 episodes, p = 0.012). Although it was possible to discontinue maintenance dosages of corticosteroids in 65% of males, corticosteroid discontinuation was possible in only 17% of females (p less than 0.001). Furthermore, in a stepwise logistic regression analysis that included age, crossmatch (no female recipients with positive results, three males with positive results), cause of heart failure, and hemodynamic status before transplantation, females were more likely to experience a rejection episode than males (p less than 0.001). Although female recipients experience rejection episodes more than their male counterparts after heart transplantation and are more likely to require maintenance corticosteroid therapy, survival and the incidence of infectious complications are not different.

Antibodies, Monoclonal↗