Evaluation and treatment of constipation in pregnancy:Examination using the Japanese version of the constipation evaluation scale

OBJECTIVES

No study has examined the effects of new constipation treatment drugs released in recent years in pregnant women. This prospective cohort study aimed to examine and compare the perinatal prognosis, efficacy rate, and safety of drugs frequently used to treat constipation.

METHODS

The study included 211 perinatally managed individuals who answered a self-administered questionnaire during the second trimester and after delivery. The Japanese version of the constipation evaluation scale (Constipation Assessment Scale [CAS] long-term [LT] version) was used for the subjective evaluation of defecation status.

RESULTS

Participants aware of constipation had significantly higher CAS scores than those who were unaware. Some participants with a CAS score of 5 points (treatment range) had no subjective symptoms of constipation, whereas some participants with a CAS score of ≤ 5 points were aware of constipation. Regarding the time of onset, 60% of those who had constipation before pregnancy had a high rate of constipation during pregnancy and after delivery. No significant difference was noted in conventional magnesium oxide and polyethylene glycol, a relatively new daily treatment drug, in perinatal prognosis or side effects.

CONCLUSIONS

Polyethylene glycol preparations alleviate constipation without inducing diarrhea, making them an appropriate therapeutic option for pregnant women.

Effect of preparation method for radioactive iodine therapy on serum electrolytes

PURPOSE

Thyroid hormone withdrawal (THW) in preparation for radioactive iodine therapy (RIT) may lead to hyponatremia and hyperkalemia because hypothyroidism reduces the glomerular filtration rate. Using recombinant human thyrotropin (rhTSH) may avoid these changes; however, these two preparation methods have not been compared in the literature. The purpose of this study was to reveal whether THW and rhTSH as preparation methods for RIT affect serum electrolytes differently. We also evaluated clinical factors influencing the onset of hyponatremia and hyperkalemia during RIT.

MATERIALS AND METHODS

From April 2005 to December 2020, we analyzed 278 patients with thyroid cancer who received RIT. The patients were classified into two groups based on the preparation method, and renal function and serum electrolytes were compared between the groups. We also evaluated clinical factors that may affect overt hyponatremia (serum sodium level < 134 mmol/L) and hyperkalemia (serum potassium level ≥ 5.0 mmol/L).

RESULTS

Serum sodium and chloride levels in the THW group were significantly lower than those in the rhTSH group (p < 0.001 and p = 0.002, respectively). In contrast, the serum potassium level in the THW group was significantly higher than that in the rhTSH group (p = 0.008). As for clinical factors that may influence hyponatremia, age and estimated glomerular filtration rate (eGFR) were significantly associated with serum sodium level in the univariate analysis (p = 0.033 and p = 0.006, respectively). In the multivariate analysis, only age was significantly associated with serum sodium level (p = 0.030). Regarding hyperkalemia, distant metastases, the preparation method and eGFR were significantly associated with the serum potassium level in the univariate analysis (p = 0.005, p = 0.005 and p = 0.001, respectively). In the multivariate analysis, only eGFR was significantly associated with hyperkalemia (p = 0.019).

CONCLUSION

THW and rhTSH affect serum sodium and potassium levels differently. Renal function may be risk factors for hyperkalemia, whereas older age may be a risk factor for hyponatremia.

[Comparison of mediansternotomy approach vs left thoracotomy approach for distal aortic arch aneurysm, and their postoperative complications]

We performed surgery for distal arch aneurysm in 22 patients; through a mediansternotomy in 11 patients (group M), and through a left thoracotomy approach in 11 patients (group L). If the distal position of an aneurysm was located at the pulmonary hilus without severe calcification of the ascending aorta, the mediansternotomy approach was chosen, whereas if we suspected that distal anastomosis would be difficult due to severe calcification of the descending aorta or aortic dissection type B, the left thoracotomy approach was selected. The mean cardiopulmonary bypass time (min.) was 229 +/- 56 in group M and 225 +/- 47 in group L, the mean circulation arrest time (min.) was 39 +/- 19 in group M and 31 +/- 5 in group L, and the mean lowest temperature (degree C) was 22 +/- 1 in group M and 20 +/- 2 in group L. No severe cerebral or cardiac complications developed in any patients. The hospital mortality was 9% (1/11) in group M and 9% (1/11) in group L. Following discharge, 8 (73%) patients from group M and 9 (92%) from group L resumed a normal lifestyle. There were no significant differences between the 2 groups and the operative results of both approaches proved satisfactory. Therefore our indications for each surgical approach to treat distal arch aneurysm seemed appropriate.

[Simultaneous surgery for unstable angina and gastric cancer: a case report]

This report describes a case in which an 81-year-old male underwent two operations simultaneously for unstable angina and gastric cancer. Successfully performed procedures were off pump CABG with bilateral IMA, and total gastrectomy. The post operative course was uneventful. Off pump CABG is an effective procedure in patient with malignant neoplasm.

[The removal of renal carcinoma thrombus extending to the right atrium by means of extracorporeal circulation: report of a case]

A case of renal cell carcinoma with a tumor thrombus extending to the right atrium was reported. A 70-year-old woman was admitted with a diagnosis of right renal tumor which had been detected on a routine abdominal ultrasonography. MRI revealed a tumor thrombus extending into the right atrium through the inferior vena cava. A transesophageal echocardiogram confirmed that the tumor extended into the right atrium, and was not adherent to the inferior vena cava and the atrium. Right nephrectomy and removal of the tumor thrombus were performed using extracorporeal circulation. Temporary occlusion of portal venous and hepatic arterial inflow was effective in reducing blood loss. She has been doing well, and there has been no evidence of recurrence during 18 month postoperatively.

The effect of flow shear stress on endothelialization of impervious Dacron grafts from circulating cells in the arterial and venous systems of the same dog

The purpose of this report was to study effects of shear force and hemodynamic conditions that influence fallout healing in the arterial and venous systems of the same dog. Knitted Dacron grafts made impervious by a 1.5 mm thick coat of silicone rubber bonded to the external surface were implanted for 4 weeks during the same surgery in the descending thoracic aorta (DTA), abdominal aorta (AA) and inferior vena cava (IVC) of each of five dogs. Flow rates were measured during surgery and shear stresses calculated with the Hagen-Poiseuille formula. Full-wall thickness longitudinal tissue sections were embedded in resin and stained with hematoxylin and eosin for light microscopy, and in paraffin for immunocytochemistry studies with Factor VIII/von Willebrand factor, smooth muscle alpha-actin, collagen IV, laminin, and proliferating cell nuclear antigen. Scanning electron microscopy and transmission electron microscopy studies were also performed. AgNO3 was used to determine percentage of endothelial-like cell coverage on the flow surface. All grafts were patent, without hematoma or seroma. Endothelial-like cell coverage was highest in the IVC grafts and lowest in the DTA. Shear stress and flow velocity were significantly lower in IVC grafts than DTA and AA. Proliferating cell nuclear antigen indicated extensive cellular proliferation in the intima and in the interstices of the inner portion of the graft wall. The degree of fallout healing in knitted Dacron grafts made impervious by an external coat of silicone rubber varies inversely with the sheer force of blood flow in these grafts.

Early flow surface endothelialization before microvessel ingrowth in accelerated graft healing, with BrdU identification of cellular proliferation

The purpose of this report was to determine if flow surface endothelialization could precede microvessel ingrowth from the perigraft area in porous Dacron grafts, by using an accelerated graft healing model with short implant periods. Dacron grafts were implanted in the abdominal aorta of 22 dogs and wrapped in autogenous inferior vena cava (IVC), which provided excellent conditions for extramural angiogenesis, microvessel development, and ingrowth toward the graft. Retrieval times were 7 days (n = 4), 8 days (n = 5), 9 days (n = 4), 10 days (n = 3), 11 days (n = 4) and 12 days (n = 3) postoperatively. Graft surfaces were evaluated for thrombus coverage, cell coverage, and the number of micro-ostia. Components and cellular types in the graft wall and on the surface were studied and characterized with H&E, histochemical, and immunocytochemical staining. BrdU labeling was also used, to identify the areas where cells were actively proliferating. All grafts were patent. Although the degree of IVC/graft attachment varied, isolated islands of endothelial-like cells were found at the midgraft areas at each time period, and immunocytochemically confirmed as endothelial cells. There were two healing patterns: (1) surface endothelialization before microvessel/tissue ingrowth from the perigraft areas, and (2) surface endothelialization with full wall microvessel and tissue presence. Surface endothelialization was observed before perigraft tissue ingrowth, indicating that fallout healing is an independent source of endothelialization for porous grafts.

Apparent blood stream origin of endothelial and smooth muscle cells in the neointima of long, impervious carotid-femoral grafts in the dog

The purpose of this study was to determine whether endothelial and smooth muscle cells originating from the blood stream contribute to the endothelialization of impervious, small-caliber, long Dacron grafts used as extraanatomical bypasses in dogs. We implanted silicone-rubber-coated, permanently impervious grafts 64 to 77 cm long and 6 mm in diameter, made of externally supported knitted Dacron as unilateral carotid-femoral bypasses with distal femoral arteriovenous fistulae in 10 dogs for 3 months; sides were alternated between cases. Subjects received 162 mg/day of aspirin, and its effectiveness on platelet aggregation (PA) was evaluated and expressed as a PA score. Graft healing was studied by stereomicroscopy with silver nitrate staining, by light microscopy with hematoxylin-eosin and immunocytochemical staining for endothelial and smooth muscle cells, and by scanning and transmission electron microscopy. Five grafts were patent for 3 months and could be included in the healing study; the five occluded grafts thrombosed within 14 days. Although there was no transinterstitial tissue ingrowth from perigraft tissues into the impervious Dacron grafts, scattered islands of endothelial cells were conclusively demonstrated on graft flow surfaces 3 months after implantation. Average endothelial-like cell coverage of the flow surfaces was 15.6% +/- 3.8%, and alpha-actin-positive smooth muscle cells and microvessels were found beneath some of the endothelial islands. These findings suggest that blood stream-derived endothelial and smooth muscle cells play a role in the healing of the inner wall of Dacron grafts in the dog.

Early presence of endothelial-like cells on the flow surface of porous arterial prostheses implanted in the descending thoracic aorta of the dog

The purpose of this study was to investigate early arterial graft healing and its sources in porous Dacron prostheses after very short implantation periods in the dog, using extensive histologic examination of serial sections. Preclotted Dacron prostheses 6 cm long and 8 mm in diameter were implanted in the descending thoracic aorta (DTA) of 14 dogs, and retrieved at 7 days (n = 6), 10 days (n = 4), and 14 days (n = 4). The flow surface was assessed for thrombus coverage, endothelial-like cell (ELC) coverage, and the number of microvessel ostia. Where an ELC island was identified under the stereomicroscope, full-wall longitudinal tissue samples were taken, and embedded in resin for light microscopy study of 6-microns, H&E-stained serial sections to determine general healing and interstitial tissue presence. If there was more than one ELC island, another full-wall sample was taken and embedded in paraffin for staining with laminin, collagen IV, and smooth muscle alpha-actin antibodies, and PTAH. All grafts were patent with very little thrombus. Islands of endothelial-like cells were found for each time period, and on all 14-day grafts. Endothelial-like cell coverage was highest at 14 days. On 7- and 10-day grafts, cells proved to be endothelium were found in the middle of the flow surface, unconnected to either pannus or perigraft tissue ingrowth. Healing occurs as early as 7 days in porous knitted Dacron grafts. The source at periods earlier than 10 days appears to be cells from the blood stream.

[Usefulness of directional coronary atherectomy as a bail-out device for acute closure after coronary angioplasty]

The usefulness of directional coronary atherectomy (DCA) as a bail-out device for acute closure (reclosure) after percutaneous transluminal coronary angioplasty (PTCA) was evaluated. PTCA was performed in 1,023 patients (182 with acute myocardial infarction) between January 1993 and January 1994 in our hospital. Thirty-one patients (11 with acute myocardial infarction) suffered acute closure (reclosure) after PTCA. In six patients (five with acute myocardial infarction), DCA was performed as a rescue treatment for acute closure (reclosure). In three of these patients, angioscopy was performed before DCA, which demonstrated intimal tear and some thrombi although coronary angiography showed no evidence of thrombus. Bail-out DCA was successful in all six patients without complications. DCA is useful as a bail-out device for acute closure (reclosure) after PTCA when the thrombus is not massive.

Accelerated endothelialization model for the study of Dacron graft healing

Accelerated endothelialization was studied by creating a vascular tissue environment around porous Dacron grafts. Three study groups, each containing 10 dogs, were divided equally into 2- and 4-week implant periods, with 8 mm x 6 cm knitted Dacron grafts implanted in the abdominal aorta. Grafts in group 1, the control group, were implanted conventionally. In group 2 each implanted graft was completely wrapped in a resected segment of the autogenous inferior vena cava, with its intima against the wall. In group 3 the adventitial side of the vein was wrapped against the wall. The vein wrap produced accelerated endothelialization as follows: endothelial-like cell coverage scores at 2 and 4 weeks were, respectively, 78% and 98% for group 2 and 80% and 95% for group 3, compared to only 14% and 50% for group 1 (p < 0.05). The neointima, which contained smooth muscle cells, was formed as early as 2 weeks in the vein-wrapped grafts. There were no differences in the speed of healing or in healing patterns according to whether the intimal or the adventitial side of the inferior vena cava was placed against the graft. Histologic findings did not support the hypothesis that accelerated flow surface endothelialization results in direct migration of endothelial cells from the intima of the vein wrap, and there was no clear correlation between the surface endothelial-like cell coverage and microostia. To gain further insight into why accelerated healing occurs in this model, earlier observations accompanied by molecular biology analysis are needed, and vein wrap studies provide a method of comparison for this work.

Implant site influence on arterial prosthesis healing: a comparative study with a triple implantation model in the same dog

PURPOSE

The purpose of this study was to develop a cost-effective canine graft healing model that gives information on various implant sites and controls for variable factors between graft locations and between animals and to compare the influence of implant site (retropleural, retroperitoneal, and subcutaneous areas) on arterial graft healing in the same subject under such controlled study conditions.

METHODS

Five mongrel dogs were studied for 8 weeks, and one was studied for 3 years. Each received three porous Dacron grafts during the same surgery: a carotid-femoral bypass (C-FB) and interposition grafts in the descending thoracic aorta and abdominal aorta. To produce comparable shear stress calibers of the C-FB and abdominal aorta grafts were 2 mm less than those of the descending thoracic aorta, and a distal arterio-venous fistula was created to further increase the C-FB flow. For comparable blood aggregation status platelet aggregation was preevaluated and adjusted with antiplatelet agents. Graft flow surfaces were assessed for thrombus-free surface and endothelial-like cell coverage scores. Tissue samples were studied with hematoxylin-eosin, factor VIII/ von Willebrand factor, smooth muscle alpha-actin staining, and scanning electron microscopy and transmission electron microscopy.

RESULTS

All grafts were patent. Shear stress for the three grafts and platelet aggregation among the study subjects were comparable. Healing of descending thoracic aorta and abdominal aorta grafts was similar, but C-FB healing was slow, incomplete, and uneven, with a high incidence of seroma. Eight-week and 3-year results were comparable.

CONCLUSIONS

This model gives broad healing information about the areas where grafts are often implanted in humans. Eight weeks appears to be a sufficient period to reflect basic and general healing characteristics. Grafts heal better in the retropleural and retroperitoneal areas than in the subcutaneous tissues.

Effect of altered blood flow on the caliber and morphology of the internal thoracic artery in the dog

OBJECTIVE

The purpose of this study was to evaluate in dogs the effect of blood flow alteration on caliber and morphology of in situ internal thoracic arteries.

METHODS

Six dogs underwent creation of a unilateral distal arteriovenous fistula between the internal thoracic artery and vein at the sixth rib to create high flow, and in six others the internal thoracic artery was unilaterally skeletonized and dissected. For both groups the contralateral internal thoracic artery served as the control; sides were alternated among cases. Blood flow was measured for shear stress calculation before and after surgical alteration. After 2 months, internal thoracic arteries were harvested with the entire anterior chest plate, which was dynamically inflated and fixed with 10% formalin at a controlled pressure of 120 mm Hg after angiography had been done at the same pressure. The luminal diameters were then measured at eight levels on the angiograms. Arterial tissue samples were taken at three levels and embedded, sectioned, and treated with hematoxylin-eosin and Verhoeff-van Gieson stains. Digital imaging analysis was used for quantitative morphometric studies.

RESULTS

All fistulas remained patent. In comparison with control arteries, high-flow internal thoracic arteries dilated and low-flow internal thoracic arteries narrowed, which was associated with significant change in shear stress for both groups. There were no substantial structural changes in the walls of either group.

CONCLUSION

In the dog, the luminal diameter of the internal thoracic artery responds to altered blood flow without intimal thickening or other undesirable wall changes.

[Antigenicity tests of a new antineoplastic agent S-1]

The antigenicity was tested of a new antineoplastic agent S-1 (a combination of tegafur (FT), CDHP and potassium oxonate (Oxo)) in mice and guinea pigs. 1. Male BALB/c or C3H/He mice were sensitized with S-1, CDHP, Oxo, and conjugates of CDHP (or Oxo) and human serum albumin (HSA). S-1 was administered by oral gavage, and the other compounds were administered intraperitoneally with adjuvant (alum). In the heterologous passive cutaneous anaphylaxis (PCA) test, using Sprague-Dawley rats as recipients, no IgE antibodies against S-1, CDHP, or Oxo were detected to any serum obtained from the sensitized mice, and no eliciting antigenicities were seen for CDHP or Oxo. 2. Male Hartley guinea pigs were sensitized with S-1, CDHP, Oxo, and conjugates of CDHP (or Oxo) and HSA. S-1 was administered by oral gavage, and the other compounds were administered subcutaneously with Freund's complete adjuvant (FCA). The homologous PCA test, active systemic anaphylaxis test, and passive hemagglutination test showed no production of antibodies against S-1, CDHP, or Oxo in any sensitized guinea pig, and no eliciting antigenicities for CDHP or Oxo. 3. Female Hartley guinea pigs were sensitized with S-1 subcutaneously with FCA. The active cutaneous anaphylaxis test revealed that S-1 did not induce cell-mediated delayed type hypersensitivity. 4. These results indicated that S-1, Oxo, and CDHP were not antigenic in mice and guinea pigs.

[Mutagenicity study of a new antineoplastic agent S-1, and its components, CDHP, and Oxo]

S-1 is a new antineoplastic agent of a fluorinated pyrimidine derivative containing tegafur (FT), 5-chloro-2,4-dihydroxypyridine (CDHP) and potassium oxonate (Oxo) in a molar ratio of 1:0.4:1 with the aim of prolonging the effective plasma concentration of 5-fluorouracil (5-FU) and reducing its dose-limiting gastrointestinal toxicity. As a part of the safety evaluation of S-1, reverse mutation tests using bacteria and chromosomal aberration tests using cultured cells, CHL/IU, were conducted to test the in vitro mutagenicity of S-1, CDHP and Oxo. All S-1 doses are expressed as the content of FT. 1. The reverse mutation tests were carried out on S-1 at 1.02-520 micrograms/plate, on CDHP at 39.1-5000 micrograms/plate, and on Oxo at 78.1-5000 micrograms/plate using Salmonella typhimurium strains TA100, TA1535, TA98, and TA1537 and Escherichia coli WP2uvrA. None of the test compounds induced a significant increase over solvent controls in the number of mutant colonies in any tester strains in either system, with or without mammalian metabolic activation (S9 Mix). 2. For the in vitro chromosomal aberration tests, Chinese hamster lung cells (CHL/IU), were treated with S-1 at 27.5-220 micrograms/ml for 24 hr or at 6.88-27.5 micrograms/ml for 48 hr without S9 Mix, and at 110-880 micrograms/ml with S9 Mix, with CDHP at 365-1460 micrograms/ml (10 mM), and with Oxo at 122-1950 micrograms/ml (10 mM), with and without S9 Mix. S-1 with and without S9 Mix, and Oxo only for 48 h treatment without S9 Mix, induced chromosomal aberrations, while CDHP did not. 3. The present study indicates that S-1 was nonmutagenic in bacteria, but clastogenic in vitro. CDHP had no in vitro mutagenic or clastogenic activity. Oxo was positive in the in vitro chromosomal aberration test, but negative in the reverse mutation test.

[Immunotoxic effects of a new antineoplastic agent S-1 in mice--comparison with S-1, UFT and 5-FU]

The immunotoxicity of S-1, which is a new antineoplastic agent, was investigated in BALB/c mice. S-1 contains tegafur (FT), CDHP, and potassium oxonate (Oxo) in a molecular ratio of 1:0.4:1. 5-fluorouracil (5-FU) and UFT were used as reference drugs. S-1 and reference drugs were administered by oral gavage for 7 days. The high dose employed in this study was determined as the maximally tolerated dose of a 9-day repeated-dose study in sarcoma 180-bearing mice. Decreased body weight was observed in mice treated with 5-FU and UFT but not in those treated with S-1. A significant decrease in thymus and spleen weight was observed in S-1-, UFT- and 5-FU-treated mice, and the degree was same for the three drugs. Though the number of white blood cells decreased dose-dependently for the three drugs, S-1 had the weakest effect. The number of red blood cells also decreased, but the effect was not dose-dependent, and its magnitude was the same for the 3 drugs. S-1 induced a dose-dependent decrease in the IgM antibody PFC response to sheep erythrocytes. The delayed type hypersensitivity response used a footpad reaction method was significantly suppressed at the highest dose of S-1. 5-FU and UFT suppressed humoral and cell-mediated immunity in almost the same manner as S-1. The degree of suppressive effects was greater on the humoral immune response than on the cell-mediated immune response. The number of CFU-GM colonies was significantly decreased in the highest dose group of each drug and in a lower group as well in S-1-treated mice. This finding might reflect the fact that S-1 induced continuous high levels of 5-FU in the blood. Under these experimental conditions, S-1 induced immunosuppressive effects in BALB/c mice, and the degree of suppression was almost same as that induced by 5-FU and UFT.

Immunotoxic effect of low dose cisplatin in mice

The immunosuppressive effects of cisplatin at relatively low doses were investigated in CD-1 mice. Mice were injected intraperitoneally with 8, 40 and 200 micrograms/kg cisplatin for 10 days. A decrease in body and thymus weights was observed at 200 micrograms/kg. Though there were no dose-related effects on the IgM antibody response to sheep erythrocytes, a statistically significant reduction of the contact hypersensitivity response (CHR) was seen at 200 micrograms/kg. In vivo and in vitro effects of cisplatin on T- and B-lymphocyte function were assessed by proliferative response to concanavalin A and lipopolysaccharide, respectively. Cisplatin inhibited splenic T-lymphocyte function more than splenic B-lymphocyte function. These data indicate that a relatively low dose of cisplatin induce immunosuppressive effects in mice with a greater effect on T-lymphocytes than the B-lymphocytes.

Histologic observation of continuity of transmural microvessels between the perigraft vessels and flow surface microostia in a porous vascular prosthesis

To ascertain the histologic relationship between flow surface microostia and perigraft vessels in the healing of a porous vascular prosthesis, a series of careful histologic examinations were carried out on a preclotted, knitted Dacron graft, 8 mm in diameter and 7 cm long, after implantation in the canine infrarenal abdominal aorta for 3 months. Four adjacent longitudinal tissue blocks were taken from the middle for evaluation by means of light microscopy, scanning electron microscopy, transmission electron microscopy, and immunocytochemical staining, and the remainder of the specimen was stained with silver nitrate to allow visualization of microostia and cell borders on the flow surface. Following identification of two microostia adjacent to the area where samples had been taken for general healing evaluation, a 3 x 8 mm full-thickness block containing the microostia was embedded in glycol methacrylate and stained with hematoxylin and eosin. Of 240 serial sections cut from this block, 80 were prepared and examined. Silver staining revealed 42 microostia on the flow surface. Light, scanning, and transmission electron microscopy with endothelial factor VIII/von Willebrand factor stain confirmed a single layer of endothelial cells on the flow surface, and beneath was a well-organized neointima containing fusiform cells confirmed as smooth muscle by alpha-actin stain. Light microscopy of the serial sections revealed transmural microvessels, lined with endothelium, extending continuously between the flow surface ostia and the perigraft vessels in this porous vascular prosthesis.

Effect of differential shear stress on platelet aggregation, surface thrombosis, and endothelialization of bilateral carotid-femoral grafts in the dog

PURPOSE

The purpose of this study was to determine the effects of increased shear stress on the aggregability of platelets as they traverse a long, small-caliber (6 mm) Dacron graft in the dog and on the surface thrombosis and endothelialization of such a graft.

METHODS

Each of nine dogs received bilateral carotid-femoral artery grafts, approximately 75 cm long, for 3 months; one graft of each pair had a distal femoral arteriovenous fistula to produce a higher shear rate than the contralateral graft. Platelet aggregation scores were determined on blood withdrawn from the external jugular vein and from the proximal and distal ends of the grafts in each animal. Graft flow rates, which were used in the computation of shear stress, and luminal pressure gradients through grafts were measured during surgery and specimen retrieval. Specimens were studied with light microscopy after hematoxylin and eosin and immunocytochemical staining and by scanning electron and transmission electron microscopy to evaluate the nature, composition, and thickness of the flow surface lining, as well as the transmural healing.

RESULTS

Two high-shear stress and two low-shear stress grafts occluded unilaterally; five dogs had bilaterally patent grafts, allowing comparative analyses. All subjects had low platelet aggregability with aspirin. Platelet aggregation scores taken from proximal and distal ends of the grafts were not significantly different. The high-shear stress grafts had significantly more endothelial-like cell coverage (p < 0.0371) than the low-shear stress grafts, less flow-surface thrombus (p < 0.0056), and a thinner surface lining (p < 0.0029), on both the neointima and pseudointima.

CONCLUSIONS

In subjects with low platelet aggregation scores, long Dacron grafts do not elevate platelet aggregability of blood flowing through them. High-shear stress grafts have less flow surface thrombus, more endothelialization, and a thinner surface lining than do low-shear stress grafts.

Comparison of the effect of monopolar and bipolar cauterization on skeletonized, dissected internal thoracic arteries

The internal thoracic artery is preferable to the saphenous vein for use as a conduit for coronary artery bypass. More extensive use is possible if this artery is mobilized in a skeletonized form to provide greater length. Internal thoracic arteries are usually mobilized with cauterization. This study compared the effectiveness and effects on neighboring areas of division of the branches of the canine internal thoracic artery with bipolar cauterization and monopolar cauterization. Branch closure was significantly more secure in the bipolar cauterization group, with bleeding in 25 (9%) of 279 branches of 15 internal thoracic arteries treated with monopolar cauterization, in contrast to bleeding in 4 (1.3%) of 306 branches in the 15 internal thoracic arteries treated with bipolar cauterization, which were paired with the group treated with monopolar cauterization. The group of internal thoracic arteries treated with monopolar cauterization had a significantly higher prevalence of leakage when luminal pressure was increased from 120 to 160 mm Hg. Scanning electron microscopy demonstrated partial loss of endothelial cells on the flow surface of internal thoracic arteries treated with bipolar cauterization, compared with almost complete loss of endothelial cells around the orificial areas after monopolar cauterization. Secondary bipolar cauterization treatment caused only slightly more damage than primary treatment, but secondary monopolar cauterization was much more severe and extensive than primary treatment. These data suggest that bipolar cauterization is preferable to monopolar cauterization for skeletonized dissection of the internal thoracic artery.

Klippel-Trenaunay syndrome associated with splenomegaly: report of a case

We report herein the case of a 19-year-old woman, diagnosed as having Klippel-Trenaunay syndrome at the age of 3 years, who presented to our hospital with severe abdominal pain. Abdominal computed tomography revealed splenomegaly, ascites, and paracentesis confirming an intraabdominal hemorrhage. Thus, an emergency laparatomy was performed for a suspected splenic rupture, and 2.5 L of blood was drained from the abdominal cavity. Splenomegaly was confirmed, and a splenectomy was performed. The patient's postoperative course was complicated by disseminated intravascular coagulation, but she recovered and was discharged 3 weeks following surgery. Pathological examination of the spleen suggested that the splenomegaly was caused by high venous pressure due to splenic vein stenosis. To our knowledge, this is the first reported case of Klippel-Trenaunay syndrome associated with marked splenomegaly.

[Mutagenicity tests of tazobactam/piperacillin, tazobactam and piperacillin]

As a part of safety tests of tazobactam/piperacillin (TAZ/PIPC), the reverse mutation tests using bacteria, the chromosomal aberration tests using cultured cells and the micronucleus tests using male mice were conducted in order to evaluate the in vitro and in vivo mutagenicity of TAZ, PIPC, TAZ/PIPC. 1. The reverse mutation tests were carried out on TAZ, PIPC and TAZ/PIPC at dose ranges, where few antibacterial effects could be detected, using Salmonella typhimurium strains TA100, TA1535, TA98 and TA1537, and Escherichia coli WP2uvrA. All of three test articles showed that no significant increases were observed in the number of colonies in all tester strains in both systems, with and without mammalian metabolic activation (S9 Mix), as compared with solvent controls. 2. The chromosomal aberration tests were carried out on these test articles using cultured Chinese hamster lung cells (CHL). The cells were treated with TAZ, PIPC or TAZ/PIPC at the doses of 2.5, 5.0 and 10 mM with and without S9 Mix. In the test of PIPC with S9 Mix, the dose of 1.25 mM was set in addition to the three doses. The incidences of structural- and numeral-aberration were 0-3% in the absence or presence of mammalian metabolic activation system, and no significant increases were observed in the incidence of chromosomal aberrations as compared with solvent controls. 3. The micronucleus tests were carried out at doses of 625-5000 mg/kg of TAZ or TAZ/PIPC, or at 625-2500 mg/kg of PIPC. The femoral marrow cells were 48 h after administering intravenously to CD-1 male mice. The frequencies of polychromatic erythrocyte with micronuclei were 0.02-0.17%, 0.02-0.10% and 0.03-0.07% in the groups treated with TAZ, PIPC and TAZ/PIPC, respectively, and no significant increases were observed with dose dependence. The results indicated that these test articles were negative in the assessment standard using the background data. 4. The present study indicates that TAZ, PIPC and TAZ/PIPC have no in vitro and in vivo mutagenic potential.

[Antigenicity tests of tazobactam/piperacillin, tazobactam and piperacillin]

The antigenicity tests of Tazobactam/piperacillin (TAZ/PIPC), tazobactam (TAZ:beta-lactamase inhibitor) and piperacillin (PIPC:penicillin antibiotic) were performed in mice and guinea pigs. The following results were obtained. 1. TAZ/PIPC, TAZ or PIPC had no immunogenicity and allergenicity in either passive cutaneous anaphylaxis (PCA) test using BALB/c and C3H/He mice or in PCA test using guinea pigs. 2. Guinea pigs sensitized with TAZ/PIPC, TAZ or PIPC showed no anaphylactic symptoms in active systemic anaphylaxis (ASA) test. 3. Guinea pig PCA tests using protein conjugates as sensitizing and challenging antigens showed positive reactions. Immunological cross-reactivity tests were performed by using these conjugates in guinea pig PCA reaction. Results showed that TAZ/PIPC and PIPC cross-reacted with penicillin G (PCG) and ampicillin (ABPC), but not with cephalothin (CET) and cephmetazol (CMZ). TAZ did not cross-react with PCG, ABPC, CET or CMZ. 4. From the results of the passive hemagglutination (PHA) test, no antibody against TAZ/PIPC, TAZ or PIPC was detected. 5. In direct Coombs' test using human blood, TAZ/PIPC, TAZ, PCG and CET showed positive reactions at 20-80, 5-20, 80 and 10-20 mg/ml, respectively. 6. The results of a test on in vitro covalent binding activity with human serum albumin indicated that the order of binding potency was CET > CMZ > ABPC > PCG = PIPC > TAZ under the physiological condition (pH 7.2-7.4), and was CMZ > CET > ABPC > PIPC > TAZ > PCG under the alkaline condition (pH 10.0-10.5), respectively.

Risk assessment in immunotoxicology. II. Relationships between immune and host resistance tests

We have reported on the design and content of a screening battery using a "tier" approach for detecting potential immunotoxic compounds in mice (Luster et al., Fundam. Appl. Toxicol., 10, 2-19, 1988). The data base generated from these studies, which consists of over 50 selected compounds, has been collected and analyzed in an attempt to improve future testing strategies and provide information to aid in developing future quantitative risk assessment for immunotoxicity. In a recent study it was shown that as few as two or three immune parameters were needed to predict immunotoxicants in mice (Luster et al., Fundam. Appl. Toxicol., 18, 200-210, 1992). In particular, enumeration of lymphocyte populations and quantitation of the T-dependent antibody response were particularly beneficial. Furthermore, commonly employed apical measures (e.g., leukocyte counts, lymphoid organ weights) were fairly insensitive. The present analyses focus on the use of this data base to develop statistical models that examine the qualitative and quantitative relationship(s) between the immune function and host resistance tests. The conclusion derived from these analyses are: (1) A good correlation exists between changes in the immune tests and altered host resistance in that there were no instances where host resistance was altered without affecting an immune test(s). However, in some instances immune changes occurred without corresponding changes in host resistance. (2) No single immune test could be identified which was fully predictive for altered host resistance, although most assays were relatively good indicators (i.e., > 70%). Several others, such as proliferative response to lipopolysaccharide and leukocyte counts, were found to be relatively poor indicators for host resistance changes. (3) The ability to resist infectious agent challenge is dependent upon the degrees of immunosuppression and the quantity of infectious agent administered. (4) Logistic and standard regression modeling using one extensive chemical data set from the immunosuppressive agent, cyclophosphamide, indicated that most immune function-host resistance relationships followed linear rather than linear-quadratic (threshold-like) models. For most of the relationships this could not be confirmed using a large chemical data set and, thus, a more mechanistically based approach for modeling will need to be developed. (5) Using this limited data set, methods were developed for modeling the precise quantitative relationships between changes in selected immune tests and host resistance tests.

Topical application of T-2 toxin inhibits the contact hypersensitivity response in BALB/c mice

T-2 toxin, a trichothecene mycotoxin, has previously been shown to alter immune functions and promote skin tumors. We demonstrate that topically applied T-2 toxin reduces the ear swelling response to oxazolone challenge in BALB/c mice. For this reduction in ear swelling to occur, toxin application must be at, or within, 1 h after challenge. Dose-response studies showed a 44% reduction in ear swelling with 30 ng of T-2 toxin as compared with a similar reduction with 300 ng of dexamethasone. T-2 toxin did not affect Ag transport from the challenge site to the draining lymph nodes as measured by FITC transport. However, T-2 toxin significantly reduced both MHC class II (Ia) expression and Ag presentation at the same concentrations. Because T-2 toxin, a known protein synthesis inhibitor, was found to inhibit protein synthesis in epidermal cell cultures as measured by [3H]-leucine incorporation, cycloheximide was also examined. Cycloheximide reduced both oxazolone-induced ear swelling and Ag presentation in a similar manner to T-2 toxin. One mechanism of action for T-2 toxin in reducing the contact hypersensitivity response is via inhibition of protein synthesis and effective Ag presentation by epidermal Langerhans cells. This may involve alterations in Ia Ag expression, although a role for class II in the induction phase of the contact hypersensitivity response has not been established definitively.

Topical application of T-2 toxin inhibits the contact hypersensitivity response in BALB/c mice

T-2 toxin, a trichothecene mycotoxin, has previously been shown to alter immune functions and promote skin tumors. We demonstrate that topically applied T-2 toxin reduces the ear swelling response to oxazolone challenge in BALB/c mice. For this reduction in ear swelling to occur, toxin application must be at, or within, 1 h after challenge. Dose-response studies showed a 44% reduction in ear swelling with 30 ng of T-2 toxin as compared with a similar reduction with 300 ng of dexamethasone. T-2 toxin did not affect Ag transport from the challenge site to the draining lymph nodes as measured by FITC transport. However, T-2 toxin significantly reduced both MHC class II (Ia) expression and Ag presentation at the same concentrations. Because T-2 toxin, a known protein synthesis inhibitor, was found to inhibit protein synthesis in epidermal cell cultures as measured by [3H]-leucine incorporation, cycloheximide was also examined. Cycloheximide reduced both oxazolone-induced ear swelling and Ag presentation in a similar manner to T-2 toxin. One mechanism of action for T-2 toxin in reducing the contact hypersensitivity response is via inhibition of protein synthesis and effective Ag presentation by epidermal Langerhans cells. This may involve alterations in Ia Ag expression, although a role for class II in the induction phase of the contact hypersensitivity response has not been established definitively.

Thymocyte injury after in vitro chemical exposure: potential mechanisms for thymic atrophy

In addition to hepatic injury, thymic atrophy is a common observation in rodent subchronic toxicity studies. We have examined representative chemicals which produce thymic atrophy in rodents for their ability to cause direct thymocyte injury because the mechanism(s) responsible for these effects have not been determined. Although a number of the compounds examined failed to have any observable direct effect on thymocytes, others either inhibited lymphocyte proliferation or initiated cell death. In the latter group, thymocyte death was always preceded by increases in intracellular Ca++ and involved, to varying degrees, necrotic and apoptotic events. Apoptosis, as evidenced by cellular DNA cleavage into multiples of 180-200-base pair oligonucleotides and partial cell protection by cycloheximide treatment, was most evident after treatment with acetaldehyde or dibutyltin dichloride. A number of compounds that produce thymic atrophy also inhibited T lymphocyte proliferation without evidence of cell death. Considering that many of the compounds tested failed to produce any evidence of direct thymocyte injury (i.e., necrosis, apoptosis or inhibition of cell proliferation), indirect mechanisms may also be involved in thymic atrophy and may target prothymocytes in the bone marrow, after normal homing patterns or injure the thymic epithelium. Thus, it appears that a variety of mechanisms may be responsible for chemical-induced thymic atrophy and/or injury.

Effect of prostaglandin I2 analogue TRK-100 on the suppression of intimal fibrous proliferation

This study investigated the effect of prostaglandin I2 analogue (TRK-100) on the healing of arterial anastomoses. The infrarenal abdominal aorta was divided and reanastomosed immediately in rabbits. A control group of rabbits were fed commercial rabbit food (ORC 4); a cholesterol group of rabbits were fed a diet with 1% cholesterol added to ORC 4; and a TRK group of rabbits received the same diet as the cholesterol group, but TRK-100 was given subcutaneously at a dose of 0.3 mg (TRK-I group) or 1.0 mg (TRK-II group) every other day. After 3 months a blood sample was taken for biochemical analysis, and the abdominal aorta was harvested for histologic examination. The serum lipid and thromboxane B2 concentrations and the thromboxane B2/6-keto prostaglandin F1 alpha ratio in the TRK groups were significantly lower than in the cholesterol group. The proliferative connective tissue did not cover the anastomotic suture line in either the control or the TRK groups. However, the suture line was covered completely by connective tissue in the cholesterol group. Intimal thickness in the cholesterol group was greater than in either the control or the TRK-II group (p less than 0.01 and p less than 0.05, respectively). These data suggest that TRK-100 may suppress intimal fibrous proliferation at anastomotic suture lines by a mechanism affecting the thromboxane B2/6-keto prostaglandin F1 alpha ratio.

[Antigenicity tests of suplatast tosilate (IPD-1151T)]

Antigenicity of suplatast tosilate (IPD-1151T) was investigated in guinea pigs and mice. The results were as follows: 1. Homologous passive cutaneous anaphylaxis (PCA), active systemic anaphylaxis (ASA), active cutaneous anaphylaxis (ACA) and Schultz-Dale reaction tests were carried out using guinea pigs which were immunized orally with IPD-1151T alone or subcutaneously with IPD-1151T and Freund's complete adjuvants (CFA). Positive reactions in these tests were not produced by eliciting injection of IPD-1151T or its metabolite, M-1. On the other hand, the sensitization of ovalbumin (OVA) with CFA produced positive reactions in all of PCA, ASA, ACA and Schultz-Dale tests. 2. Heterologous passive cutaneous anaphylaxis (PCA) test using rats was carried out using two strains of mice (C3H/He and BALB/c) which were immunized orally with IPD-1151T alone or intraperitoneally with IPD-1151T and aluminum hydroxide gel (Alum) as an adjuvant. No animals showed positive reaction to both eliciting antigens, IPD-1151T and M-1. On the other hand, a positive reaction in PCA test to eliciting antigen, OVA, was obtained in rats treated with sera of mice sensitized with OVA plus Alum. 3. These findings showed that IPD-1151T had no antigenicity in guinea pigs and mice.

Pentamidine isethionate reduces Ia expression and antigen presentation by Langerhans cells and inhibits the contact hypersensitivity reaction

The mechanism of action of pentamidine isethionate, a diamidino compound used in the treatment of Pneumocystis carinii pneumonia, is unknown. We recently reported that this drug may inhibit the release of inflammatory mediators from alveolar macrophages, which may be associated with its antiparasite activity. As a potential anti-inflammatory agent, we report that topically applied pentamidine reduces ear swelling in the contact hypersensitivity reaction to oxazolone in B6C3F1 mice. The application of pentamidine must occur within 1 h, at the challenge site, to be effective. Topical application appears necessary, because i.v. injection had no effect on reduction of ear swelling. In dose-response studies, a 50% reduction in ear swelling was achieved with as little as 20 micrograms of pentamidine. Pentamidine did not affect Ag transport from the challenge site to the draining lymph nodes, as measured by FITC transport. However, there was a 30 to 40% reduction in epidermal cells expressing Ia Ag from pentamidine-treated mouse ears, compared with control. Ia expression is almost exclusively limited to Langerhans cells in the normal epidermis. This reduction in Ia expression was not due to simple depletion of Langerhans cells by pentamidine, because CD45 expression was unaffected. Concurrent with reduced Ia expression, Ag presentation by pentamidine-treated Langerhans cells was also reduced. Taken together, a mechanism of action for pentamidine in inhibition of the contact hypersensitivity reaction appears to be via a reduction in Ag presentation by decreasing Ia+ Langerhans cells.

Pentamidine isethionate reduces Ia expression and antigen presentation by Langerhans cells and inhibits the contact hypersensitivity reaction

The mechanism of action of pentamidine isethionate, a diamidino compound used in the treatment of Pneumocystis carinii pneumonia, is unknown. We recently reported that this drug may inhibit the release of inflammatory mediators from alveolar macrophages, which may be associated with its antiparasite activity. As a potential anti-inflammatory agent, we report that topically applied pentamidine reduces ear swelling in the contact hypersensitivity reaction to oxazolone in B6C3F1 mice. The application of pentamidine must occur within 1 h, at the challenge site, to be effective. Topical application appears necessary, because i.v. injection had no effect on reduction of ear swelling. In dose-response studies, a 50% reduction in ear swelling was achieved with as little as 20 micrograms of pentamidine. Pentamidine did not affect Ag transport from the challenge site to the draining lymph nodes, as measured by FITC transport. However, there was a 30 to 40% reduction in epidermal cells expressing Ia Ag from pentamidine-treated mouse ears, compared with control. Ia expression is almost exclusively limited to Langerhans cells in the normal epidermis. This reduction in Ia expression was not due to simple depletion of Langerhans cells by pentamidine, because CD45 expression was unaffected. Concurrent with reduced Ia expression, Ag presentation by pentamidine-treated Langerhans cells was also reduced. Taken together, a mechanism of action for pentamidine in inhibition of the contact hypersensitivity reaction appears to be via a reduction in Ag presentation by decreasing Ia+ Langerhans cells.

Eicosapentanoic acid suppresses intimal hyperplasia after expanded polytetrafluoroethylene grafting in rabbits fed a high cholesterol diet

The effect of purified eicosapentanoic acid on intimal fibrous hyperplasia in expanded polytetrafluoroethylene grafts was examined in 18 rabbits undergoing infrarenal aorta reconstruction. Six rabbits received commercial rabbit chow (control group), six a regular diet supplemented with 1% cholesterol (cholesterol group), and six the cholesterol diet with 91.1% pure eicosapentanoic acid 500 mg/day (eicosapentanoic acid group). Grafts were harvested 3 months after surgery for histologic examination. The platelet count and serum beta-thromboglobulin and platelet factor 4 concentrations were not significantly different between groups. Serum arachidonic acid level in the cholesterol group was significantly higher than in the control group, and serum eicosapentanoic acid levels in the eicosapentanoic acid group were significantly higher than in the remaining two groups. Intergroup differences in serum 6-keto-prostaglandin F1 alpha and thromboxane B2 concentrations were not significant. Intimal thickness at midgraft was 5.2 +/- 6.2 microns in the control group, 67.6 +/- 46.9 microns in the cholesterol group, and 19.2 +/- 18.4 microns in the eicosapntanoic acid group. intimal thickness in the cholesterol group was greater than in either the control or licosapentanoic acid group (p less than 0.01 and p less than 0.05, respectively). These data suggest that eicosapentanoic acid reduces intimal fibrous proliferation in expanded polytetrafluoroethylene grafting as a result of hypercholesterolemia and that this effect is independent of the platelet count, activated platelet factors, and the prostacyclin/thromboxane A2 ratio.

Antigenicity tests on propiverine hydrochloride in guinea pigs and mice

Antigenicity of propiverine hydrochloride (P-4), a newly developed drug for pollakisuria, was investigated in guinea pigs and mice. 1. Two strains of mice (BALB/c and C3H/He) showed no production of antibodies against P-4 inoculated with aluminum hydroxide gel (alum) as an adjuvant, judged by the heterologous passive cutaneous anaphylaxis (PCA) test using rats. On the other hand, antibodies against P-4-ovalbumin (OVA) conjugate inoculated with alum was definitely detected. 2. In the studies with guinea pigs, both the inoculation of P-4 alone and of P-4 with Freund's complete adjuvant (FCA) as an adjuvant did not produce positive reactions in any of homologous passive cutaneous anaphylaxis (PCA), active systemic anaphylaxis (ASA) and passive hemagglutination (PHA) tests. On the other hand, the inoculation of P-4-OVA conjugate with FCA produced positive reaction in all of PCA, ASA and PHA tests. 3. In the active cutaneous anaphylaxis (ACA) test in guinea pigs inoculated with P-4-OVA conjugate with FCA, positive reaction was produced by eliciting injection of P-4-human serum albumin (HSA). 4. In the Schultz-Dale reaction test, any animals in any groups showed no positive reaction to both eliciting antigens, P-4 and P-4-HSA. 5. These findings showed that P-4 had no antigenicity in guinea pigs and mice.

[Peri- and postnatal study of cefodizime sodium in mice--intravenous administration from late gestation through period of lactation]

Peri- and postnatal study of cefodizime sodium (THR-221), a new developed cephem-type antibiotics, was carried out with ICR mice. THR-221 at dose levels of 0, 300, 1000 and 3000 mg/kg/day were administered intravenously to pregnant and delivered dams from day 15 of gestation through day 21 of lactation. No changes in body weights of dams in all treated groups but slight decrease in food consumptions of 3000 mg/kg/day group were observed. Treated sites, tails of a few dams in this group, were affected with inflammatory lesions because of repeated dosing. Neonates from dams treated with 3000 mg/kg/day were slightly decreased in body weight at birth. At term sacrifice of F 1 of 10 weeks age, absolute and relative spleen weights were decreased in male 3000 mg/kg/day group and in female 1000 and 3000 mg/kg/day group. No effects on other physical, behavioral or reproductive ability examinations of F 1 offspring were showed. It is suggested that no effect dose level of THR-221 is 1000 mg/kg/day and that of F 1 offspring is 300 mg/kg/day.

Alpha 2-adrenergic receptors on canine platelet membranes characterized by [3H]-yohimbine binding

Alpha 2-adrenoceptors on canine platelet membranes were characterized by [3H]-yohimbine binding. Binding of [3H]-yohimbine to the membranes was rapidly saturated, stable and reversible with high affinity. Dissociation constant (KD) calculated from Scatchard analysis of the equilibrium experiments was 1.89 +/- 0.20 nM which was in good agreement with KD (1.97 +/- 0.60 nM) obtained in the kinetic experiments. Maximal binding sites of the ligand (Bmax) was 249 +/- 20 fmoles/mg protein. Adrenergic antagonists inhibited the ligand binding in following rank order of potency; yohimbine greater than phentolamine greater than phenoxybenzamine greater than corynanthine greater than prazosin. This order was in good correlation with that for these drugs in the inhibition of platelet aggregation. Hill coefficients for the displacement curves of the ligand binding by adrenergic agonists were less than 1.0 which were converted into near unity in the presence of 5'-guanylyl-imidodiphosphate (100 microM). These results demonstrate that canine platelet membranes have alpha 2-adrenoceptors and suggest that the binding of these receptors to adrenergic agonists is regulated by guanine nucleotides.

Location of Streptococcus mutans in the dentinal tubules of open infected root canals

Seventy-six teeth from open canals were extracted to prepare serial longitudinal sections. The sections were made from apical portions of the teeth and stained. Ninety similar teeth were extracted to prepare dentinal splinters with files from the enlarged infected canal. The splinters were spread on a selected medium to grow S. mutans. S. mutans was detected in 48.7% of the 76 teeth examined. The distance of invasion of S. mutans in the dentinal tubules revealed by immunofluorescence averaged 509 micrometer from the canal wall and reached 1150 micrometer, depending on the serogroups of S. mutans. Unidentified germs in the sections which were demonstrated by Gram's stain invaded further than S. mutans. The frequency of appearance of the serogroups of S. mutans was 32.6% (d), 27.9% (c), 24.4% (a), and 15.5% (b).