A modified stapling technique for esophagojejunostomy after total or proximal gastrectomy

BACKGROUND

Stapling devices reduce the leakage rate of digestive tract anastomoses, but they increase the risk of strictures. We investigated a newly modified technique of end-to-end anastomosis stapling in esophagojejunostomy after total or proximal gastrectomy.

STUDY DESIGN

A modified stapling technique (using a stapled anastomosis between esophageal mucosal and intact jejunal layers, with hand-sewn seromuscular sutures between the esophagus and jejunum) was used in 21 patients (modified group), while a conventionally stapled anastomosis was performed in 17 patients (conventional group). The incidence and severity of dysphagia and the size of the anastomosis as determined from x ray films were compared in the two groups.

RESULTS

The modified technique provided significantly better results for dysphagia severity than the conventional method (p = 0.0025). Most of the patients in the modified group had mild dysphagia, and most patients in the conventional group complained of moderate or severe dysphagia. In the modified group, the inner diameter of the anastomosis was 12.1 +/- 2.5 mm, significantly larger than that in the conventional group (10.0 +/- 1.8 mm; p = 0.009).

CONCLUSIONS

The use of our modified stapling technique can minimize the risk of anastomotic stricture and the feeling of dysphagia after esophagojejunostomy.

Immunohistochemical evaluation of lymph node micrometastases from gastric carcinomas

BACKGROUND

The clinicopathologic significance of micrometastases to lymph nodes, consisting of a single carcinoma cell or a small cluster of carcinoma cells and confirmed only by special staining, was evaluated in patients with gastric carcinoma.

METHODS

The authors studied 2446 lymph nodes removed during surgery for 109 cases of gastric carcinoma, including Stages I, II, III and IV. Tissue preparations were stained with hematoxylin and eosin (H&E), Alcian blue in combination with periodic acid-Schiff stain, and antibodies against cytokeratin and carcinoembryonic antigen (CEA).

RESULTS

Metastases were confirmed in 230 lymph nodes (9.4%) stained with H & E, and an additional 201 lymph nodes (17.6%) had micrometastases identified only by immunostaining for cytokeratin (197 lymph nodes) and/or CEA (66). Carcinomas with micrometastases had significantly worse prognoses at Stage II. Between the two histologic types of gastric carcinoma, the diffuse type had more micrometastases than the intestinal type.

CONCLUSIONS

The findings of this study indicate that the presence of micrometastases in lymph nodes is an indispensable factor in determining the prognosis of gastric carcinoma patients.

MAD-related genes on 18q21.1, Smad2 and Smad4, are altered infrequently in esophageal squamous cell carcinoma

The MAD (mothers against decapentaplegic)-related genes, Smad2 (former name MADR2 or JV18-1) and Smad4 (former name DPC4), have been identified on chromosome 18q21.1. We analyzed 30 primary esophageal squamous cell carcinomas (ESCC) and 7 cell lines derived from ESCC for intragenic mutations and loss of heterozygosity (LOH) of the Smad2 and Smad4 genes. LOH was detected in 5 of 14 (35%) informative cases. However, no mutations in either gene were detected in either the primary carcinomas or the cell lines, and only a G-to-A base transition within the 3'-untranslated region of the Smad4 gene was observed in a carcinoma. There were no homozygous deletions in either of the genes in the cell lines. MAD-related genes on chromosome 18q21.1 are altered infrequently in ESCC.

Immunohistochemical evaluation of lymph node micrometastases from gastric carcinomas

BACKGROUND

The clinicopathologic significance of micrometastases to lymph nodes, consisting of a single carcinoma cell or a small cluster of carcinoma cells and confirmed only by special staining, was evaluated in patients with gastric carcinoma.

METHODS

The authors studied 2446 lymph nodes removed during surgery for 109 cases of gastric carcinoma, including Stages I, II, III and IV. Tissue preparations were stained with hematoxylin and eosin (H&E), Alcian blue in combination with periodic acid-Schiff stain, and antibodies against cytokeratin and carcinoembryonic antigen (CEA).

RESULTS

Metastases were confirmed in 230 lymph nodes (9.4%) stained with H & E, and an additional 201 lymph nodes (17.6%) had micrometastases identified only by immunostaining for cytokeratin (197 lymph nodes) and/or CEA (66). Carcinomas with micrometastases had significantly worse prognoses at Stage II. Between the two histologic types of gastric carcinoma, the diffuse type had more micrometastases than the intestinal type.

CONCLUSIONS

The findings of this study indicate that the presence of micrometastases in lymph nodes is an indispensable factor in determining the prognosis of gastric carcinoma patients.

External biliary jejunal drainage through a percutaneous endoscopic gastrostomy for tube-fed patients with obstructive jaundice

We describe a new procedure, which can help patients with obstructive jaundice improve their quality of life (QOL). Although percutaneous transhepatic biliary drainage (PTBD) can relieve jaundice, the procedure has some disadvantages. Percutaneous endoscopic gastrostomy (PEG) is a useful method for providing nutritional support to patients unable to swallow. We have combined these two techniques. We used the combination ofa 20-F catheter and a 9-F jejunal catheter for PEG. The PTBD catheter and the 9-F jejunal catheter are connected outside the patient's body. Externally drained bile from the PTBD catheter can flow back into the jejunum, and the opening between the 20-F catheter and the 9-F jejunal catheter is used for tube feeding. This procedure was adopted in a patient. Since the procedure, the patient's nutritional status and daily living activities have improved. We conclude that the procedure is useful for tube-fed patients with obstructive jaundice.

[Comparison of echograms by a microscanner and histological findings of the common bile duct, in vitro study]

To confirm the relationship between the layer structure of the common bile duct by a microscanner (MS) and its histological features, we performed a study using the pinning method with needles and catgut. The locations of 67 needles inserted at random depths in 29 slices of the resected common bile duct from 18 patients were confirmed both by a MS and a microscope. The wall of the common bile duct was delineated as a two- (42 points) or three-layer structure (25 points); "low and high" or "high, low, and high echoic layers" from the mucosal side. A fibrotic layer (ss 1) was often (56/67 points, 16/18 patients) seen in the subserosa (ss) containing nerves and vessels larger than 100 mu in diameter. Among the 51 needle echoes demonstrated in the inner hypoechoic layer, 2 were located in the mucosa (m), 12 in the fm, 19 in the af, 17 in the ss 1, and 1 in the fatty layer of the ss (ss 2). Five of the 6 needles in the outer hyperechoic layer were in the ss 2, and 1 was in the pancreatic parenchyma (pa). Four of the 8 needles at the border between the inner hypoechoic layer and the outer hyperechoic layer histologically corresponded to fm, af, ss 1, and pa, respectively, and the other four corresponded to ss 2. From these results, we conclude that the inner hypoechoic layer contains not only m, fm, and af, but also ss 1. Therefore, this should be kept in mind for the preoperative assessment of the depth of bile duct carcinoma by MS.

Expression of neurotrophic factors in cultured human retinal pigment epithelial cells

PURPOSE

To see if cultured human retinal pigment epithelial (RPE) cells have the capacity to synthesize neurotrophins, including nerve growth factor (NGF), brain-derived growth factor (BDNF), and neurotrophin-3 (NT-3).

METHODS

Expression of mRNAs for the neurotrophins was studied by the reverse transcription polymerase chain reaction (PCR) method. Quantitative analysis of the gene expression was done by using a semiquantitative PCR method. Secretion of NGF-like immunoreactivity (NGF-LI) into the culture medium was analyzed by enzyme immunoassay (EIA).

RESULTS

Cultured human RPE cells were found to express mRNAs for NGF, BDNF and NT-3. In the conditioned culture medium of the human RPE, 9.44 +/- 0.62 pg/ml (mean +/- SEM, n = 6) NGF-LI was found. Pretreatment of human RPE cells with interleukin-l (IL-1) (20 ng/ml), phorbol myristate acetate (PMA) (100 ng/ml) or tumor necrosis factor-alpha (TNF-alpha) (40 ng/ml) was found to increase the mRNA expression of neurotrophins and also to increase secretion of NGF-LI into the culture medium.

CONCLUSIONS

Our data demonstrate that cultured human RPE cells have the capacity to synthesize neurotrophins, and that various stimulations can up-regulate gene and protein expression of NGF by these cells.

Effects of fructose-induced hypertriglyceridemia on hepatorenal toxicity of acetaminophen in rats. II. Role of enhancement of fructose metabolism and overproduction of triglyceride in the liver and kidney on hepatorenal toxicity of acetaminophen

Fructose-induced hypertriglyceridemic rats are resistant to hepatoxicity and susceptible to nephrotoxicity of acetaminophen (APAP) as compared with normal ones. The present studied were designed to evaluate how fructose-treatment affects the developmental mode of hepatorenal toxicity of APAP. First, following fructose-pretreatment for various durations (1 day, 1 week or 3 weeks), 1-day-fructose-pretreatment induced hypertriglyceridemia and enhancement of APAP-nephrectoxicity simultaneously. However, it took at least 3 weeks for fructose-pretreatment to reduce APAP-hepatotoxicity. Second, following fructose, sucrose or glucose-pretreatment for 3 weeks, fructose-pretreated rats showed marked hypertriglyceridemia and modification of APAP-hepatorenal toxicity. Sucrose-pretreated rats showed less effects than fructose-pretreated rats. Glucose-pretreated rats showed no changes in plasma triglyceride and APAP-hepatorenal toxicity. Third, rats with hypertriglyceridemia induced by olive oil or Triton WR-1339 which did not produce enhanced metabolism and triglyceride-overproduction in the liver and kidney showed no modification of APAP-hepatorenal toxicity. Pretreatment of glycerol which was metabolized in liver and kidney and induced an overproduction of triglyceride resulted in an enhancement of APAP-nephrotoxicity. These results indicate that an enhancement of fructose metabolism and an overproduction of triglyceride in liver and kidney are responsible for the modification of APAP-hepatorenal toxicity in fructose-induced hypertriglyceridemic rats.

Induction of cerebrospinal fluid eosinophilia in rats by the intraventricular injection of Angiostrongylus cantonensis antigen

Resistance to Angiostrongylus cantonensis is contingent upon the generation of an eosinophilic response in the CSF of infected hosts. We have studied the parameters required for the generation of this CSF eosinophilia in normally permissive rats. We initially induced a marked peripheral eosinophilia in rats by infection with either Mesocestoides corti or Angiostrongylus cantonensis or the surgical transfer of A. cantonensis young adult worms (YA) into their pulmonary arteries. Next, we injected various antigens into the ventricles of these rats. A. cantonensis-preinfected rats demonstrated significant CSF eosinophilia following injection of A. cantonensis egg antigen, 1st-stage larval (L1) antigen, or M. corti antigen, but not following YA antigen inoculation. A. cantonensis egg and M. corti antigens were potent chemoattractants for eosinophils in an in vitro chemotaxis assay. These data indicate that peripheral eosinophilia, meningeal stimulation by A. cantonensis infection and the presence of potent chemoattractants, e.g., egg and L1 antigens are prerequisites for CSF eosinophil accumulation in permissive rat hosts.

Ventilatory response at the onset of voluntary exercise and passive movement in endurance runners

The present study was performed to examine whether or not the ventilatory response at the onset of voluntary exercise and passive movement in endurance runners is the same as in untrained subjects. Twelve long-distance runners belonging to the varsity athletic club and 13 untrained subjects of our university participated as subjects in this study. Maximum oxygen uptake was significantly higher in the endurance runner group [mean (SD) 70.8 (4.7) ml.kg-1.min-1] than in the untrained group [49.8 (6.3) ml.kg-1.min-1]. Cardiorespiratory responses during voluntary exercise and passive movement of alternate flexion-extension of the right and left legs for about 15 s at a frequency of about 60 rpm, were determined by means of breath-by-breath techniques. Minute inspiratory ventilation (VI), tidal volume (VT), respiratory frequency (fb), cardiac output (Qc), stroke volume (SV) and heart rate (HR) increased significantly immediately at the onset of voluntary exercise and passive movement. The incremental rate for VI was greater than that for Qc. Average values and standard deviations of changes in VI were calculated as the difference between the mean of the first and second breath and the mean of five breaths preceding the exercise or movement. The rates obtained in voluntary exercise and passive movement in the endurance runner group [2.34 (0.82) and 1.72 (0.71 l.min-1), respectively] were significantly (P < 0.05) lower than those in the untrained group [4.16 (2.66) and 2.71 (1.56 l.min-1), respectively]. Also changes in VT and HR were significantly lower in the endurance group than in the untrained group with regard to both voluntary exercise and passive movement. The results suggest that the magnitude of cardiorespiratory responses at the onset of voluntary exercise and passive movement in humans is influenced by chronic endurance training for long periods.

Effects of combined beta-adrenergic and cholinergic blockade on the initial ventilatory response to exercise in humans

To elucidate whether combined adrenergic and parasympathetic blockade would affect the ventilatory response to exercise, especially at the initial stage (phase I), six healthy subjects performed a brief and light voluntary bilateral leg extension exercise and passive movements under the conditions of control (before the blockade) and after intravenous administration of combined beta-adrenergic (propranolol, 0.2 mg.kg-1) and muscarinic (atropine, 0.04 mg.kg-1) receptor antagonists. The movements were continued only within two breaths after the onset of the motion. Ventilation increased immediately and significantly (P < 0.05) within the first breath at the onset of voluntary exercise in all conditions as compared with at rest. However, the magnitude of increase in mean ventilation within two breaths at the start of exercise as against the resting value (delta ventilation) was significantly less (P < 0.05) after the combined blockades (2.5 l.min-1) than in the control condition (3.7 l.min-1). Passive movements showed a similar but smaller change as compared with voluntary exercise. The heart rate response to exercise was attenuated by the combined blockade while cardiac output showed a slight change at the onset of exercise. It is concluded that phase I should occur despite the inhibited activity of the beta-adrenergic and the cholinergic systems; nevertheless, the response was attenuated by the combined blockade. These results suggest a possible role of the beta-adrenergic and/or cholinergic systems in the rapid increase in ventilation that occurs at the start of exercise.

Elevated serum interleukin-6 and decreased thyroid hormone levels in postoperative patients and effects of IL-6 on thyroid cell function in vitro

We studied a wide variety of surgical patients to determine whether serum levels of interleukin-6 (IL-6) or tumor necrosis factor-alpha (TNF-alpha) correlate with the changes in serum thyroid hormone levels of the postoperative period. Surgical procedures were divided into minor surgery (cholecystectomy, n = 12), moderate surgery (colorectal cancer and stomach cancer, n = 54), and extensive surgery (esophageal cancer or pancreatic cancer, n = 6). One day after surgery, serum free T3 levels decreased in all 3 groups when compared to the preoperative values; serum free T4 levels did not change regardless of surgical procedure. Serum TSH levels decreased significantly 1 day after surgery in the groups of moderate and extensive surgery. Serum levels of IL-6 increased 12 h after surgery and began to decrease gradually thereafter. There was no change in serum levels of TNF-alpha before and after surgery. The increment of serum IL-6 was dependent on the surgical procedures: the more extensive the surgery, the greater the increase in serum IL-6. Serum free T3 and free T4 levels were inversely correlated with the serum levels of IL-6. To further examine whether IL-6 is responsible for alteration of thyroid hormone production, cultured porcine thyroid follicles were exposed to 0 to 20 ng/ml of recombinant human IL-6 for 24 to 48 h. Then, type 1 5'-deiodinase activity (T4 to T3 converting enzyme), iodide uptake, and thyroid peroxidase (TPO) activity were measured. Our in vitro experiments showed no effect of IL-6 on these parameters. In summary, surgical procedure can cause elevation of serum IL-6 and decrease in serum free T3 levels. However, IL-6 alone does not appear to be a strong candidate for alteration of thyroid hormone production including T3 generation from T4.

Cytokine responses in mice infected with Angiostrongylus cantonensis

For determination of the kinetics of cytokine production and its possible role in host resistance to Angiostrongylus cantonensis in the mouse, Th1 [interleukin 2 (IL-2) and interferon gamma (IFN-gamma] and Th2 (IL-5 and IL-4) cytokine production in the cerebrospinal fluid (CSF), sera, and culture supernatants of spleen cells (SC) or cervical lymph-node cells (CLNC) of infected BALB/c and C57BL/6 mice was assessed by a sandwich enzyme-linked immunosorbent assay (ELISA). IL-5 and IL-4 were detected in CSF of both strains, with a peak response occurring at around days 12-15 and 20 postinfection (p.i.), respectively. A reverse transcriptase-polymerase chain reaction (RT-PCR) assay also revealed prominent IL-5 and IL-4 mRNA expression in T-cells but not in eosinophils in CSF. SC and CLNC stimulated with A. cantonensis young adult-worm antigen released IL-5 in vitro at and after day 20 p.i. Contrarily, IFN-gamma production in CSF and SC or CLNC culture supernatants was almost negligible before day 30 p.i. IL-5, IL-4, and IL-2 production in culture supernatants was rather prominent in resistant C57BL/6 mice as opposed to susceptible BALB/c mice as assessed by the magnitude of increase over preinfection levels. Antigen-specific IgG1 (but not IgG2a) responses were more prominent in C57BL/6 mice than in BALB/c mice. These data suggest that systemic and local Th2 cytokine responses, especially those involving IL-5, are predominant in A. cantonensis-infected mice and that IL-5 is an important cytokine underlying the innate resistance of the mouse against A. cantonensis.

[Ultrasonographic study of rectal carcinoid tumors]

To compare intraluminal ultrasonographic (ILUS) findings with histological findings of rectal carcinoid tumors, 35 patients with rectal carcinoid tumors were reviewed. The results were as follows: 1) The rectal wall was visualized as a seven- or nine-layer structure by means of ILUS in 81% of the patients. 2) The possibility that the thin hyperechoic third layer above the tumor on ILUS corresponds to the muscularis mucosae and fibrointerstitium above the tumor histologically. 3) In cases with relatively high internal echoes, the amount of fibrointerstitium exceeded that of tumor cells histologically. 4) In cases with nonuniform internal echo patterns, tumor cells were separated by thick fibrointerstitium forming nodular nests.

Obesity is necessary but not sufficient for the development of diabetes mellitus

To investigate whether inheritance or obesity plays a more important role in the development of non-insulin-dependent diabetes mellitus (NIDDM), female Otsuka-Long-Evans-Tokushima Fatty (OLETF) rats, which possess the diabetogenic gene, ODB-1, and Long-Evans-Tokushima-Otsuka (LETO) rats, which have no ODB-1, were compared. Neither strain becomes obese and diabetic when bred ordinarily. Female OLETF rats and male and female LETO rats were assigned to two groups of 20 rats each. Obesity was induced in one group by feeding a high-energy "cafeteria" diet (group D), and the other group was given standard chow (group C). Twenty male OLETF rats were used as NIDDM positive controls. At 25 weeks of age, the mean body weight of group D male LETO and female OLETF rats increased at a rate similar to that of male OLETF rats; female LETO rats did not show increased body weight. The incidence of diabetes mellitus in obese female OLETF rats in group D and positive control male OLETF rats was the same (80%). Only 30% of obese male LETO rats in group D developed diabetes mellitus. The insulin response to intravenous glucose in group D female OLETF rats was the highest for all groups but not sufficient to decrease blood glucose levels. In female OLETF rats, glucose infusion rate (GIR) during a euglycemic-hyperinsulinemic clamp test in group D was decreased to 50% of the group C value and tissue glucose uptake as determined by 3H-glucose infusion was significantly decreased in muscle. In male LETO rats, group D GIR was mildly decreased (80% of group C value) compared with the GIR of female OLETF rats. For obese group D female OLETF rats, abdominal fat increased more with obesity than in their male LETO counterparts. GIR was inversely correlated with the weight of abdominal fat when the data of all groups of animals were combined. The expression of GLUT4 mRNA and its protein level in adipose and muscle tissues and tumor necrosis factor alpha (TNF-alpha) protein in adipose tissue were not significantly different between group D and group C of both strains. In conclusion, the incidence of diabetes in female OLETF rats that possess the diabetogenic gene was significantly greater than in the LETO strains that do not possess the gene, in the presence of excess adiposity.

Phase II study of chemoradiotherapy for advanced squamous cell carcinoma of the thoracic esophagus: nine Japanese institutions trial

A phase II study of chemoradiotherapy for advanced squamous cell carcinoma of the thoracic esophagus was carried out cooperatively by nine Japanese institutions. Forty-five patients with thoracic advanced squamous cell carcinoma, who had T4 tumor or distant lymph node metastasis (M1(LYM)), were enrolled in the study for treatment with cisplatin (70 mg/m2) on days 1 and 36, and 5-fluorouracil infusion (700 mg/m2) on days 1-4 and 36-39 sandwiched around external beam irradiation (60 Gy over 6 weeks). Of the 45 evaluable patients, 37 (84.1%) completed the treatment. The overall response rate was 64.4%, and the complete response rate 8.9%. The median duration of response was 125.0 days for patients who achieved complete and partial response. The 50% median survival time was 215 days. There was one toxicity-related death due to radiation pneumonitis. The major form of toxicity exceeding grade 2 was myelosuppression and anorexia, but grade 4 toxicity was also observed (2 pulmonary, 1 severe hypoxemia, 1 severe cardiac failure and 1 mental disturbance). The results showed that this form of chemoradiotherapy had a satisfactory effect and might be useful for treatment of inoperable advanced esophageal cancer.

Effects of SM-9018, a novel 5-HT2 and D2 receptor antagonist, on electrically-evoked [3H]acetylcholine release from rat striatal slices

1. Electrical stimulation (1 Hz) of striatal slices evoked Ca(+2)-dependent [3H]ACh release, which was inhibited by the D2 agonist quinpirole (QPL). 2. SM-9018 and other neuroleptics antagonized the QPL-induced inhibition of the evoked [3H]ACh release. The relative potencies of the neuroleptics in antagonizing the QPL action were nemonapride > haloperidol approximately equal to SM-9018 > > chlorpromazine > > SCH 23390, and the rank order, except for nemonapride, was consistent with their binding affinities to striatal D2 receptors. 3. SM-9018 was weaker than haloperidol in enhancing the [3H]ACh release evoked by higher frequency (3 Hz) stimulation, the enhancement being abolished by the depletion of endogenous dopamine with reserpine pretreatment. 4. The selective 5-HT2 antagonist LY 53857 significantly attenuated the stimulatory effects of haloperidol on the 3 Hz-evoked [3H]ACh release. 5. These findings suggest that SM-9018 is as potent as haloperidol in antagonizing the QPL action on [3H]ACh release at striatal D2 receptors, but is weaker than haloperidol in enhancing the [3H]ACh release under high-frequency stimulation. The 5-HT2 blocking activity of SM-9018 seems to be involved in the latter effects.

Inactivation of the CDKN2 gene by homozygous deletion and de novo methylation is associated with advanced stage esophageal squamous cell carcinoma

We examined the genomic status of the CDKN2 gene including de novo methylation of 5' CpG islands in primary and metastatic tumor samples from 31 patients with esophageal squamous cell carcinoma. One somatic frame shift mutation (1 of 31; 3.2%) was identified by PCR-single strand conformational polymorphism analysis and DNA sequencing. Homozygous deletion and de novo methylation of the gene were confirmed in 5 (16%) and 6 (19%) of 31 patients, respectively. Homozygous deletion and de novo methylation were significantly associated with silencing of gene expression (P < 0.01). Aberrations of the CDKN2 gene were detected in tumors with lymph node metastasis and muscular invasion (12 of 22; 54%) and in none of stage I tumors (0 of 9.0%; P < 0.05). These results suggest that homozygous deletion and de novo methylation are predominant mechanisms of inactivation of the CDKN2 gene and may be associated with metastatic and invasive phenotypes of esophageal squamous cell carcinoma.

Allogeneic hepatocyte and fetal liver transplantation and xenogeneic hepatocyte transplantation for Nagase's analbuminemic rats

Allogeneic hepatocyte and fetal liver transplantation and xenogeneic hepatocyte transplantation were performed in Nagase's analbuminemic (NAR, RT1(1)) rats, and the functional and morphological changes of intrasplenic grafts under FK506 immunosuppression were examined. Normal male Wistar Shi rats (RT1k) and male BALB/C mice were used as donors. Serum albumin levels in FK506-treated NAR rats 4 wk after all three transplantation techniques performed were significantly higher than those in animals without immunosuppression, indicating the intrasplenic grafts had survived in FK506-treated groups. On histological examination, hepatocyte colonies were detected in FK506-treated rats after allogeneic hepatocyte or fetal liver transplantation. NAR rats are expected to be useful for studies on allogeneic or xenogeneic hepatocyte transplantation under immunosuppression by various methods.

Antimicrobial activity of superoxidized water

We tested the antimicrobial activity of superoxidized water against methicillin-sensitive Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, Staphylococcus epidermidis, Serratia marcescens, Escherichia coli, Pseudomonas aeruginosa and Burkholderia cepacia. The number of bacteria was reduced below detection limit following incubation in superoxidized water for 10 s. The bactericidal activity of superoxidized water was similar to that of 80% ethanol, but superior to that of 0.1% chlorhexidine and 0.02% povidone iodine. We conclude that superoxidized water is a low cost but powerful disinfectant.

Evaluation of a novel osteogenic factor, bone cell stimulating substance, in a rabbit cranial defect model

A novel osteogenic factor, bone cell stimulating substance (BCSS), was recently isolated from bovine bone. Unlike the bone morphogenetic proteins, which are generally 20- to 40-kDa glycoproteins belonging to the transforming growth factor-beta superfamily, BCSS is a 2.5-kDa, water-soluble polypeptide. This study evaluated the osteogenic potential of BCSS in combination with coralline-derived porous hydroxyapatite to reconstruct a large, nonhealing cranial defect in the rabbit. Twenty-four rabbits underwent a 16 x 20 mm full-thickness (extradural) excision of the parietal bones and were divided into six groups of four rabbits each. Group 1 through 5 were reconstructed with 16 x 20 x 1.5 mm hydroxyapatite implants treated with: (1) 20 osteogenic units (424 micrograms) BCSS, (2) 8 osteogenic units (170 micrograms) BCSS, (3) 4 osteogenic units (85 micrograms) BCSS, (4) 0 osteogenic units (424 micrograms) inactive BCSS analog, or (5) left untreated. Group 6 was left unreconstructed. Implants were harvested at 12 weeks and analyzed for percentage of lamellar bone formation by a computerized microscope video image analysis system. Groups reconstructed with BCSS-treated hydroxyapatite implants demonstrated more bone ingrowth than did the control hydroxyapatite groups not treated with BCSS (inactive BCSS analog or untreated). Linear regression dose-response analysis indicated an average 3.2 percent increase in bone ingrowth for a 10-U increase in BCSS (p = 0.043). The unreconstructed control group demonstrated no healing. With a molecular mass of only 2.5 kDa and its identity not completely known, BCSS is a novel factor that seems to possess osteogenic potential similar to that of previously investigated osteogenic proteins.

Pharmaceutical studies for gene therapy: expression of human Cu, Zn-superoxide dismutase gene transfected by lipofection in rat skin fibroblasts

To evaluate whether lipofection using Lipofectin is suitable for delivering foreign genes into skin fibroblasts as target cells, we performed experiments using human superoxide dismutase (hSOD) and neomycin-resistance (Neo) genes as models in rat skin fibroblasts (FR and primary cells) in vitro. The amounts of DNA used in the lipofection procedure significantly affected the transfection efficiencies, and the optimal amounts were determined for all cells used. However, the efficiencies in rat skin fibroblasts were about 20-fold higher than that in rat lung epithelial-like cells (L2 cells). The differences in plasmid vectors (pRc/RSV-SOD and pRc/CMV-SOD) hardly affected the transfection efficiencies. The amounts of Lipofectin significantly affected the transfection efficiencies, and the optimal amounts were determined for both types of skin fibroblasts. However, cytotoxic effects in both skin fibroblasts were observed with high doses of Lipofectin. On the other hand, with optimal amounts of DNA and Lipofectin, the reporter gene (NeoT) introduced into cells was mainly integrated into the host cell chromosome. Western blot analysis showed the continuous expression of hSOD protein for at least 45 d in skin fibroblasts transfected with the expression plasmid for hSOD by Lipofectin under the optimal conditions, and the cellular SOD activity fluctuated in parallel with the expression of hSOD protein. Differences in the type of cells also affected the expression of hSOD. These results indicate that it is necessary to set up optimal conditions for transfection using Lipofectin for each cell type, and that transfection with Lipofectin under optimal conditions may be an efficient method for introduction of foreign genes into skin fibroblasts for use as a clinical delivery system of therapeutic protein.