Biomedical subjects

S J Soong

Publications and source records attributed to S J Soong.

At least 19 recordsLinked to original sources

PubMed1992

Oral folic acid supplementation for cervical dysplasia: a clinical intervention trial.

OBJECTIVE: We attempted to evaluate the effect of oral folic acid supplementation on the course of cervical dysplasia. STUDY DESIGN: A total of 235 subjects with grade 1 or 2 cervical intraepithelial neoplasia were randomly assigned to receive either 10 mg of folic acid or a placebo daily for 6 months. Clinical status, human papillomavirus type 16 infection, and blood folate levels were monitored at 2-month intervals. Outcome data were subjected to chi 2 analysis. RESULTS: The prevalence of human papillomavirus type 16 infection initially was 16% among subjects in the upper tertile of red blood cell folate versus 37% in the lower tertile (trend p = 0.035). After 6 months no significant differences were observed between supplemented and unsupplemented subjects regarding dysplasia status, biopsy results, or prevalence of human papillomavirus type 16 infection. CONCLUSION: Folate deficiency may be involved as a cocarcinogen during the initiation of cervical dysplasia, but folic acid supplements do not alter the course of established disease.

Administration, Oral↗

PubMed1992

Second-look laparotomy and salvage therapy: a research modality only?

Two hundred twelve patients who underwent second-look laparotomy as part of their treatment for epithelial ovarian cancer were evaluated. Factors associated with positive second looks were initial stage, tumor grade, age, and residual disease (P less than 0.05). One factor not of significance was whether adjuvant therapy was platinum based. Initial stage only was associated with recurrence after a negative second look (P less than 0.001). When controlled for volume of disease no difference in survival between various salvage therapies could be demonstrated. Survival between patients with recurrence after negative second look and patients with microscopic residual disease was similar even though the former group was not treated until recurrence (P = 0.75). Second-look laparotomy does not improve survival with currently existing salvage modalities and should primarily be confined to those patients willing to participate in research protocols evaluating new second-line therapy.

Adult↗

PubMed1992

A matched comparison of single and triple incision techniques for the surgical treatment of carcinoma of the vulva.

Thirty-two patients with invasive squamous cell carcinoma of the vulva (SCC) undergoing radical vulvectomy or radical local excision with bilateral superficial groin node dissection using a triple incision technique (TI) were matched for new FIGO stage, lymph node status, size of lesion, and site of lesion with patients with SCC undergoing traditional radical vulvectomy with en bloc bilateral groin (but not pelvic) node dissection using a single incision (SI) technique. Average operative time (134 min: 191 min), blood loss (424 ml: 733 ml), and hospital stay (9.7 days: 17.2 days) were significantly less in the TI group. After SI 6/32 (19%) patients and after TI 1/32 (3%) patients experienced complete breakdown of the groin wounds. There was no significant difference in overall survival (P = 0.56) or disease-free survival (P = 0.53) between the two groups. There was no significant difference in survival between the two groups by lesion size or by FIGO (1989) stage. Disease recurred in six patients after SI compared with seven after TI (P = 0.75). There were no skin bridge recurrences in the TI group. Two patients in each group had isolated vulvar recurrences and all four were successfully treated by local excision. These data indicate that outcome following TI surgery is essentially equal to that of SI in early-stage disease but major morbidity is much reduced.

Adult↗

PubMed1992

Prognostic significance of cervical lymph node metastases in differentiated thyroid cancer.

During the last decade, several analyses of prognostic factors for differentiated thyroid cancer (DTC) have been reported. Although these studies have established a framework for rational treatment planning, they have not fully answered questions regarding the prognostic significance of cervical lymph node metastases. An analysis of patients treated for DTC at our institution over a 34-year period has shown several factors to be significant by log-rank analysis, including the presence of cervical lymph node metastases, age greater than or equal to 50 years, a primary cancer size of greater than 3.0 cm, and distant metastases. Further analysis has shown the node-negative and node-positive patient groups to be similar in regard to age, size of primary cancer, and the presence of distant metastases. This report compares our data with those of other studies that have investigated the association of cervical lymph node metastases and a poorer prognosis in patients with DTC. When considered as a group, these studies support the finding of the prognostic significance of cervical lymph node metastases, particularly that of palpable lymphadenopathy in older patients.

Adenocarcinoma↗

PubMed1992

Disseminated herpes zoster in the immunocompromised host: a comparative trial of acyclovir and vidarabine. The NIAID Collaborative Antiviral Study Group.

Seventy-three immunocompromised patients with disseminated herpes zoster were evaluated in a double-blind controlled trial of acyclovir (n = 37) versus vidarabine (n = 36) therapy. Acyclovir was administered at 30 mg/kg/day at 8-h intervals and vidarabine was given as a continuous 12-h infusion at 10 mg/kg/day for 7 days (longer if resolution of cutaneous or visceral disease was incomplete). No demographic differences existed between treatment groups. No deaths attributable to varicella-zoster virus infection occurred within 1 month of treatment. Neither rates of cutaneous healing, resolution of acute neuritis, and frequency of postherpetic neuralgia nor adverse clinical and laboratory events differed between treatment groups. Acyclovir recipients were discharged from the hospital more promptly than vidarabine recipients (P = .04, log rank test). These data indicate that disseminated herpes zoster is amenable to therapy with either acyclovir or vidarabine; resultant mortality is low.

Acyclovir↗

PubMed1992

Features of asthma in older adults.

A study compared clinical and functional features of elderly patients with asthma to younger patients at a university medical center. Older patients had a larger than predicted reduction in pulmonary function parameters even though physician-assessed severity, duration of diagnosed asthma, and smoking status were no different between groups. A significant increase in the comorbid diagnosis of chronic obstructive pulmonary disease was noted in older patients with asthma. These two points support the hypothesis that long-standing asthma may lead to irreversible airflow obstruction. Older patients reported better medication compliance and decreases in some respiratory symptoms and demonstrated lower health care utilization.

Adolescent↗

PubMed1992

A simple, single, trial-learning paradigm for conditioned increase in natural killer cell activity.

A change in natural killer (NK) cell activity can be conditioned with one trial learning when conditioned stimulus (CS) precedes the unconditioned stimulus (US). To avoid the problems associated with two reexposures in our earlier studies, we have developed a reliable and simple conditioning protocol utilizing the one trial learning and one reexposure to the odor CS. The conditioned change in NK cell activity was significantly different (P less than 0.05) from the control groups of mice. The paradigm is short and simple in that the conditioned change could be demonstrated within 3 days. We have also compared the effects of temporal association of CS and US on conditioned increase in NK cell activity. Forward conditioning (CS preceded the US) demonstrated a conditioned change, but the backward conditioning protocol did not. The paradigm provides a reliable approach to the study of mechanisms of the phenomenon of odor-NK conditioning.

Administration, Inhalation↗

PubMed1991

Inhibition of fluoropyrimidine catabolism by benzyloxybenzyluracil. Possible relevance to regional chemotherapy.

Regional infusion with fluoropyrimidines is useful in the treatment of hepatic metastases. However, the effectiveness of regional infusion is minimized by rapid degradation of 5-fluorouracil (FUra) and 5-fluoro-2'-deoxyuridine (FdUrd) by the liver which limits the availability of drug for anabolism to active metabolites. 5-Benzyloxybenzyluracil (BBU) is a potent inhibitor of dihydropyrimidine dehydrogenase (DPD), the initial enzyme in FUra catabolism (Naguib FMN, el Kouni MH and Cha S, Biochem Pharmacol 38: 1471-1480, 1989). The effect of BBU on fluoropyrimidine catabolism in the liver was evaluated using the isolated perfused rat liver (IPRL). BBU infused at 0.35 microM over the course of 1 hr demonstrated no hepatotoxicity as measured by bile flow, O2 uptake and lactate dehydrogenase leakage. The effect of BBU (0.35 microM) on the catabolism of FUra (10 microM) or FdUrd (10 microM) was quantitated by HPLC at 5- or 10-min intervals over a 1-hr period. BBU maximally inhibited FUra catabolism by approximately 83%. Further studies utilizing short-term (20 min) infusion of BBU prior to administration of FUra suggested that the inhibition of DPD was reversible. While FdUrd phosphorolysis was not affected, subsequent catabolism of FUra decreased by 70%. Studies on isolated hepatocytes indicated that the increased FUra level in perfusate resulted from inhibition of FUra catabolism and not from inhibition of FUra transport. The significant inhibition of FUra catabolism suggests that BBU may be useful in modulating regional chemotherapy by these fluoropyrimidines.

Animals↗

PubMed1991

Effect of thymic hormone treatment on several immune functions of nude mice.

Studies of the effect of short-term, intense treatment with thymic hormone on mitogen response, cytotoxicity to EL-4 lymphoma and natural killer cell (NK) activity was investigated Balb/c nude mice (about 12-16-week-old) were treated 5 times per week for 3 weeks with: Facteur Thymic Serique (FTS) and Thymopentin (TP5, Thymopoietin 32-36) at 1 microgram and 10 ng; TM4 1 ng (an enzyme resistant variant of FTS); Thymosin Fraction V (TF5), 10 and 1 microgram; and 0.1 ml saline, and killed 2 days after the last treatment. The animals were monitored for changes in weight, hematocrit, peripheral blood lymphocyte (PBL) and spleen mitogen response. Additional groups of nude mice were immunized with 1 x 10(7) 5000 R irradiated EL-4 cells 10 days before sacrifice and tested for the presence of cytotoxic T-lymphocytes (CTL). The results show that weight and hematocrit were similar among the groups. Treatment with FTS significantly elevated the number of PBL. Spleen stimulation in mice treated with 1 microgram TP5 was depressed to mitogen concanavalin A (ConA) and lipopolysaccharide (LPS) stimulation. The phytohemagglutinin (PHA) response was not different among the treatment groups. The PBL mitogen response to ConA and LPS was generally increased over saline control in the hormone treated groups but was not statistically significant. The PHA response was only slightly elevated. No CTL was generated in nude mice in any of the groups. However, there was a statistically significant general depression of NK activity in all of the hormone treated animals compared with saline. The results indicate that the basic differentiation defect of the T-cells of nude mice cannot be restored to full functional activity by short-term treatment.

Aging↗

PubMed1991

Primary surgical therapy of ovarian cancer: how much and when.

From July 1975 through December 1985, 328 patients with ovarian malignancies were treated. Of these, 302 had epithelial invasive malignancies and constitute the study group. The impact of the operative procedure, findings, and subsequent treatment is evaluated. Patients who underwent extensive debulking procedures such as bowel resection and peritoneal stripping did not have improved survival compared with those patients who did not undergo these procedures and yet had residual disease remaining (P = 0.7 and P = 0.34). Reoperating patients felt to be unresectable at the time of referral did not increase survival over reoperating patients after an attempt at chemotherapeutic reduction (P = 0.34).

Female↗

PubMed1991

Rationale for using pathologic tumor dimensions and nodal status to subclassify surgically treated stage IB cervical cancer patients.

Between 1969 and 1988, 401 patients were treated by radical hysterectomy and pelvic lymphadenectomy for Stage IB cervical carcinoma at the University of Alabama at Birmingham. In multivariate analysis, pathological tumor diameter (P less than 0.0001) and the presence of lymph node metastasis (P = 0.0005) proved to be the dominant two histopathologic features that significantly correlated with overall survival. Although 5-year survival for the overall group was 85%, 5-year survival in patients with lesions greater than 3.0 cm in diameter and with regional nodal metastasis was less than 30%. This discrepancy in survival in surgically treated early-stage cervical cancer patients supports a need for subcategorization by risk factors such as pathologic tumor dimensions and nodal status and for further investigation of alternative neoadjuvant and adjuvant therapies in those early-stage cervical cancer patients deemed at high risk for poor overall survival.

Female↗

PubMed1991

Use of brain biopsy for diagnostic evaluation of patients with suspected herpes simplex encephalitis: a statistical model and its clinical implications. NIAID Collaborative Antiviral Study Group.

Using the decision analysis technique and multivariate regression methods, a statistical model was established to define the utility of brain biopsy for diagnostic evaluation of patients with suspected herpes simplex encephalitis (HSE). Two strategies were compared: strategy I, brain biopsy with acyclovir (ACV) treatment for 10 days in biopsy-positive patients, and strategy II, ACV therapy without brain biopsy. Strategy I resulted in a greater 6-month survival rate when the likelihood of patients having HSE was less than 70%. Based on the current estimated prevalence of HSE (for patients with suspected HSE) of 35%, strategy I showed a slight advantage of a 3.2% increase in 6-month survival rate. An individual patient's chance of a positive brain biopsy can be predicted using a mathematical equation based on several important clinical assessments. This equation in conjunction with the decision analysis is a useful guide for the clinical management of patients with regard to brain biopsy.

Acyclovir↗

PubMed1991

Survey of thymic hormone effects on physical and immunological parameters in C57BL/6NNia mice of different ages.

Immunosenescence occurs with aging, which is seen in decline in response to mitogens PHA, ConA, decline in cell-mediated immunity, increase in anemia, and increase in autoimmune antibodies to erythrocytes and DNA. These studies compared FTS, TP5, TM4, and TF5 in C57BL/6NNia mice. Mice aged 4, 26, 52, 78 and 104 wk were treated with various hormones 5x/wk for 3 wk and monitored for hormonal effects on weight; hematocrit; peripheral blood, spleen, and thymic cell numbers; spleen and peripheral blood cell mitogen responses to PHA, ConA, LPS; IgM hemolysin autoantibody; and cell-mediated cytotoxicity to P815 allogenic cells. Hormone treatments altered mitogen responses, enhanced IgM hemolysin autoantibody production, and modulated cell-mediated immune responses. The effects were not consistent for every hormone. There was a tendency for enhancement in younger mice and suppression in older animals. Treatment with FTS showed the greatest changes in either enhancing or suppressing the different parameters measured. The hormonal effects appeared to be age specific in that certain activities were altered for certain age groups but not in others. Hormone treatment did not restore any immune parameters in old mice to the level of young animals. In general, the different hormones did not consistently produce the same effects in C57BL/6NNia mice of different age groups. Even though all animals received from National Institutes on Aging (NIA) animal models program were held under strictly controlled conditions, intrinsic variations between cohorts of different ages are difficult to control. Cohorts of aging animals tested at different times might be intrinsically different. This inherent variability in the cohorts could affect the range of activity, specificity and reproducibility of hormone effects in vivo. Most importantly, it should be emphasized that cross-sectional data identifies age differences rather than age changes. There is no assurance that age changes in any individual or in all subpopulations follow this pattern. In our studies only healthy animals were used. Old, sick, or tumor-bearing animals were culled out prior to being sent to us. Therefore, the 78- and 104-wk-old mice represent selected healthy cohorts. The age changes that take place can be answered only from repeated measurements made in the same individual over time.

Aging↗

PubMed1991

Three-port perineal sparing technique.

The records were reviewed of 103 patients with low-lying pelvic malignancies irradiated with a skin-sparing technique involving use of a pair of anteroposterior-posteroanterior opposed ports and a direct perineal port. Patients had rectal, anal, cervical, vaginal, urethral, or vulvar cancer. Use of a special lead compensator allowed the three beams to be applied perpendicularly to the surface, while delivery of a homogeneous dose to the pelvis and perineum was maintained. Skin dose with this method was greatly reduced compared with that delivered with simple opposing or four-port techniques, in which irradiation is tangential to the surface at the perineum. Acute perineal skin irritation was assigned a grade between 0 and 3, with grade 0 representing the least amount of irritation. All patients were in the grade 0 or grade 1 category. Patients treated for low-lying rectal carcinoma showed no increase in perineal recurrences when compared with historic control subjects. Use of this approach allowed delivery of adequate doses to the pelvis and perineum and a definite decrease in local toxic effects, and local control was not compromised.

Adenocarcinoma↗

PubMed1991

Steroid-induced weakness in patients with primary brain tumors.

Clinically significant steroid myopathy (SM) occurred in 23 (10.6%) of 216 adult patients with primary brain tumors who received 2 or more continuous weeks of daily dexamethasone therapy. SM occurred over a wide range of peak and cumulative doses of dexamethasone as well as a wide range of periods of continuous treatment. This was not an entirely random event, however, as two-thirds of the patients developed their weakness during the 9th through the 12th week of continuous dexamethasone treatment. The risk of developing SM was significantly lower in patients taking phenytoin than in patients who were not taking anticonvulsants. The only other patient or treatment factor associated with SM was a possible direct correlation with the appearance of a cushingoid body habitus. In this retrospective review, the occurrence of SM had a significant negative impact on the quality of life of all affected individuals. As expected, patients who tolerated a reduction in their steroid dose improved, while other patients suffered the combined effects of tumor progression and worsening myopathy. Substituting a nonfluorinated glucocorticoid for dexamethasone is probably advisable if neuro-oncology patients affected by SM cannot be weaned from the steroids.

Activities of Daily Living↗

PubMed1991

Role of immune cells in the Pavlovian conditioning of specific resistance to cancer.

It has been demonstrated that significant protection against YC8 lymphoma can be induced in mice preimmunized with normal DBA/2 spleen cells. The DBA/2 spleen cells used as alloantigens share minor histocompatibility determinants with the YC8 tumor. We have used this model to investigate the nature of the immunity conferred by treatment with the alloantigen and infer that the conditioned resistance observed was maintained by the same effector mechanism. The results demonstrated that repeated immunization of tumor bearing mice with the alloantigen had some beneficial effect as shown by the slower rate of growth of the tumor, and an increase in median survival time over controls. The observations showed however that once tumor was present in vivo, the use of potent tumor specific vaccine can help in increasing survival but can no longer produce high incidence of regressions and cures. Conditioning can potentiate the effects of this treatment by increasing survival and cure.

Animals↗

PubMed1991

In vivo enhancement of NK cell activity with met-enkephalin and glycyl-glutamine: their possible role in the conditioned response.

These studies investigated the effect of met-enkephalin, glycyl-glutamine, and naltrexone on NK cell activity in vivo and in vitro. It was found that both met-enkephalin (which shares the amino-terminal end of beta-endorphin) and glycyl-glutamine (which reflects the carboxyl-terminal end of beta-endorphin) can enhance the NK cell activity of mice prestimulated with a low dose (1 microgram/mouse) of poly I:C. Naltrexone had no effect. In vivo prestimulation of the mice with 1 microgram poly I:C was necessary as mice which were not pretreated with poly I:C did not show enhanced NK cell activity when treated with either met-enkephalin or glycyl-glutamine. In vitro studies however indicate that the drugs when cultured together with the NK cells from mice preactivated with poly I:C did not have a direct stimulatory effect on the NK cells. These studies imply that while beta-endorphin released from the pituitary could be involved in enhancement of activated NK cells in vivo other indirect peripheral pathways might be involved. The results suggest beta-endorphin probably reacts with other accessory type cells which in turn release the mediators which are required for the stimulation of NK cells in vivo.

Animals↗

PubMed1991

A behavioral augmentation of natural immunity: odor specificity supports a Pavlovian conditioning model.

BALB/c mice were conditioned by pairing an odor to an injection of poly-inosinic:poly-cytidylic acid (poly I:C), a strong inducer of natural killer (NK) cell activity as the unconditioned stimulus (US). When later reexposed to the odor conditioning stimulus (CS), these mice showed a conditioned augmentation of the NK cell response to a suboptimal dose of 1 microgram poly I:C. The two stimuli used in these studies were camphor (Ca) and citronella oil (Cr) odors, two chemically-related but distinct odor stimuli. The conditioned mice demonstrated the ability to discriminate between Ca and Cr, such that the conditioned response (CR) was only elicited by the odor CS used in the formation of the conditioned association. Exposure of conditioned mice to the non-associated odor stimulus on the test day did not elicit a change in the NK cell response to the suboptimal dose of poly I:C when compared to mice in the US group that had been given the US on day 0 without pairing to either odor stimulus. This specificity of the CR for the odor CS and not the unassociated odor stimulus supports the interpretation that the elevation of NK cell activity in this paradigm is due to Pavlovian conditioning and therefore dependent on central nervous system (CNS) associative processes.

Animals↗