Chromophobe cell renal carcinoma in childhood

We report the first case of chromophobe cell renal carcinoma in childhood. A 12-year-old boy presented gross hematuria following minor trauma. He was diagnosed as having a left renal tumor 45-mm in diameter. Radical nephrectomy was performed. One year later the boy was well.

Antiviral effects of 6-chloro-2',3'-dideoxyguanosine in rhesus monkeys acutely infected with simian immunodeficiency virus

A lipophilic dideoxynucleoside analogue, 6-chloro-2',3'-dideoxyguanosine (6-Cl-ddG), was expected to be effective against AIDS-related dementia. In this study, we tested the effect of 6-Cl-ddG on simian immunodeficiency virus (SIVmac239) replication in vitro and on acute infection of six rhesus monkeys (Macaca mulatta) with SIVmac239. This compound inhibited SIV-induced cytopathic effect in CEM x 174 cells and SIV replication in vitro with an ED50 value of 2.5 microM. A dose of 25 mg/kg 6-Cl-ddG was administered to three monkeys every 8 h for 10 days and an untreated group of three monkeys was injected with the solvent without drug. Although 6-Cl-ddG was not detected in the plasma, the metabolite ddG was maintained at a concentration of more than 3 microM for 8 h after administration. In the cerebrospinal fluid, the ddG concentration was 2 microM at 2 h after administration. SIV antigen (p27) and antibody appearance in the plasma were delayed for 5-8 days compared with the mock-treated group. The occurrence of lymphadenopathy in treated monkeys was delayed for 6 days compared with the mock-treated group. Signs of 6-Cl-ddG toxicity were minimal after the treatment. The results of this study provide further evidence that 6-Cl-ddG may act as a potent anti-human immunodeficiency virus agent in vivo.

Scanning electron microscopic study of erythrocyte shapes artificially jetted through tubes at different pressures by 'in vitro cryotechnique for erythrocytes'

A new cryotechnique for examining morphological changes of human erythrocytes at different jet pressures was developed in the present study. Human fresh or stored erythrocytes passing through a tube were jetted into precooled isopentane-propane mixture (-193 degrees C), which was named as 'in vitro cryotechnique for erythrocytes'. After the cryotechnique procedure, the routine freeze-substitution method and subsequent t-butyl alcohol freeze-drying method were used for preparing the scanning electron microscopic specimens. At 100 mmHg or higher pressures of jetting, lamellar-arranged erythrocytes were observed to have elongated shapes. The more the jetting pressure increased, the fewer discoid shapes of erythrocytes were observed. This cryofixation technique could preserve the morphology of erythrocytes jetting from tubes, and provide the three-dimensional image of erythrocyte surfaces, as followed by scanning electron microscopy.

Evaluation of transrectal voiding ultrasonography in men with micturition difficulties without apparent organic obstruction of the lower urinary tract

OBJECTIVE

To examine whether transrectal voiding ultrasonography (TRVUS) can evaluate voiding movement in men with dysfunctional voiding.

METHODS

Ninety-nine consecutive men complaining of voiding difficulties without benign prostatic hyperplasia, prostatic cancer, severe bladder neck contracture and urethral stricture received uroflowmetry and TRVUS. Those who had abnormal findings on both uroflowmetry and TRVUS underwent subsequent cystometry combined with electromyography (EMG) to confirm the presence of dysfunctional voiding.

RESULTS

Uroflowmetry indicated abnormal findings in 31 of the 99 patients, and TRVUS demonstrated abnormal movements of the posterior urethra during voiding in all of these 31 patients and 11 of the other 68 patients whose uroflowmetry did not indicate abnormality. TRVUS findings of the former 31 were divided into type E (the external urethral sphincter closed or intermittently opened while the bladder neck manifested an opening movement of > 7 mm during voiding in 20) and type I (both the bladder neck and external urethral sphincter manifested an intermittent movement of < 7 mm in 11). Subsequent cystometry combined with EMG in the 31 patients who had abnormal findings on both uroflowmetry and TRVUS revealed overactivity of the external urethral sphincter (OS) and underactivity of the detrusor (UD) in 85 and 35% of type-E group and 55 and 73% of type-I group, respectively. Type E included significantly more OS without UD than type I (65 vs. 18%; p = 0.0233). All of type-E (20/20) and 91% of type-I (10/11) patients had voiding difficulty which resulted from either OS or UD, while a very limited number of patients (4/31) manifested neurological symptoms such as paraplegia except for voiding difficulties.

CONCLUSIONS

Both uroflowmetry and TRVUS are easy and useful methods to evaluate dysfunctional voiding in men, especially when neural disorders or organic obstruction of the lower urinary tract are not apparent.

Developmental changes in the electrical activity of locus coeruleus neurons during cortical spreading depression

A previous study has demonstrated that during cortical spreading depression (CoSD), locus coeruleus (LC) neurons in adult rats reveal antidromic burst activity consisting of multiple initial segment (IS) spikes and IS-somatodendritic (SD) spikes with a distinct IS-SD break. In addition, the spontaneous firing rate of the neurons was reduced during CoSD. In the present experiments, we studied developmental changes in the electrical activity of LC neurons during CoSD. Since stable and repetitive DC shifts occurred in rats older than postnatal day 13 (PD13), the electrical activity of LC neurons at developmental stages later than PD13 was examined. The CoSD-related burst activity similar to that observed in adults was recorded at all stages of development, and the proportion of LC neurons showing the burst activity was nearly the same through all developmental stages and in adults. The frequency of IS spikes in the burst activity at PD13-P15 was not different from that in adults. However, the spontaneous firing rate of LC neurons at early developmental stages remained unchanged during CoSD. Based on these findings, it is conceivable that the mechanism of the generation of multiple IS spikes during CoSD at early developmental stages is different from that at later developmental stages and in adults.

Prostaglandin E1 protects against ischemia-reperfusion injury of the liver by inhibition of neutrophil adherence to endothelial cells

BACKGROUND

This study investigates the protective mechanism of prostaglandin E1 (PGE1) against hepatic ischemia-reperfusion injury in vivo. It has been demonstrated that activated leukocytes contribute to ischemia-reperfusion injury, and that administration of the monoclonal antibody (mAb) for adhesion molecules reduces the injury by inhibiting leukocyte-endothelial cell adhesion. We therefore attempted to find out whether PGE1 has an effect on the inhibition of neutrophil adherence to endothelial cells after reperfusion.

METHODS

We administered anti-intercellular adhesion molecule 1 (ICAM-1) mAb, antiserum against rat polymorphonuclear leukocytes, or PGE1 to a rat model of left lobar ischemia for 60 min followed by reperfusion. Leukocyte adherence was observed by intravital fluorescence microscopy. The effect of PGE1 on the expression of adhesion molecules was analyzed by immunohistochemistry and flow cytometry.

RESULTS

Ischemia-reperfusion caused endothelial dysfunction and hepatocellular injury with leukostasis in postsinusoidal venules. Anti-ICAM-1 mAb administration or leukopenia ameliorated both the hepatocellular injury and endothelial dysfunction. Although PGE1 administration did not affect the serum interleukin-8 level, it significantly decreased hepatic injury and leukostasis in the reperfused liver. Immunohistochemical findings showed that PGE1 decreased ICAM-1 expression on endothelial cells, but did not affect lymphocyte function-associated antigen 1, and membrane attack complex 1 on neutrophils in flow cytometric analysis.

CONCLUSIONS

We conclude that PGE1 protects the liver against ischemia-reperfusion injury by reducing leukocyte-endothelial cell adhesion via down-modulation of ICAM-1 expression on the endothelium.

Efficacy of 6-chloro-2',3'-dideoxyguanosine (6-Cl-ddG) on rhesus macaque monkeys chronically infected with simian immunodeficiency virus (SIVmac239)

To assess the therapeutic effects of 6-chloro-2',3'-dideoxyguanosine (6-Cl-ddG), a lipophilic dideoxynucleoside analogue, three rhesus macaques chronically infected with simian immunodeficiency virus (SIVmac239) were subcutaneously administered 25 mg/kg of the drug every 8 hours for 2 weeks. In two of three animals, the viral RNA in plasma and the cell-associated viral load from peripheral blood mononuclear cells were markedly decreased and the number of CD4+ and CD8+ lymphocytes were increased after 6-Cl-ddG administration. The decrease of the virus copies was associated with a reciprocal increase in the number of CD4+ lymphocytes. Additionally, a limiting dilution assay revealed a marked decrease in the lymph node cell-associated virus titer during the treatment. However, in the third monkey, the baseline of the number of CD4+ and CD8+ lymphocytes was higher than that of the other monkeys; these numbers changed very little during the treatment. In this monkey, the plasma SIV RNA level was decreased at the first week and was the same as the pretreatment level at the second week of the 6-Cl-ddG administration. In all three treated monkeys, the number of SIV RNA copies in the cerebrospinal fluid also tended to decrease during the 6-Cl-ddG treatment.

Mature CD4 single positive thymocytes in human Thymoma: T cells may differentiate in the thymic epithelial cell tumor

Human thymoma, which is occasionally associated with autoimmune disease, is a thymic epithelial cell tumor and often contains a large number of lymphocytes. In a previous study, we have shown that a proportion of CD4 single positive T cells in human thymomas lack CD3, suggesting immaturity. In this study, we focused on the rest of the CD4 single positive T cells in thymomas that expressed CD3/TcR alpha beta and investigated the maturity of single positive T cells by analyzing lymphocyte surface antigens and the cells' proliferative response to a mitogen. CD4 single positive cells that expressed CD3 or TcR alpha beta also expressed CD69 and had probably undergone positive selection in the tumor. Further, isolated CD4 or CD8 single positive cells from the thymomas responsed to a mitogen although at lower levels than the corresponding single positive cells in the peripheral blood. These results indicate that thymomas contain single positive T cells which have mature phenotype and proliferative ability, and suggest that T cells may differentiate in thymoma.

Elevated plasma thymosin-alpha1 levels in lung cancer patients

OBJECTIVE

Prothymosin-alpha, the precursor of thymosin-alpha1, may play a role in cell proliferation, and the plasma level of thymosin-alpha1 may reflect the degree of proliferation of the tumor cells.

METHODS

Recently, a new sandwich immunoradiometric assay for thymosin-alpha1 was developed using monoclonal and polyclonal antibodies. In this investigation, we used this assay to measure plasma and tissue level of thymosin-alpha1 in 131 lung cancer patients.

RESULTS

We found that the mean plasma thymosin-alpha1 levels in lung cancer patients were higher than in normal individuals (P < 0.001). However, half of the patients showed normal levels. Thymosin-alpha1 levels correlated neither with the stage nor pathological subtype of the lung cancer, and did not decrease significantly in the 4 weeks after the resection of the tumor. Thymosin-alpha1 levels of lung cancer patients with another cancer were higher than those without evidence of other cancers (P = 0.03). Survival of patients with normal levels of plasma thymosin-alpha1 was significantly better than that with higher levels (P = 0.04).

CONCLUSIONS

The plasma level of thymosin-alpha1 may be used as a marker for the prognosis of lung cancer patients. Further investigations are warranted to determine its role in the lung cancer.

Vomiting induction by ipecac syrup in dogs and ferrets

The dog has been used as an experimental animal in emesis research. In this study, we analyzed the emetic effects of ipecac syrup using a smaller animal, the ferret, and compared its response to that of the dog. Dogs and ferrets were divided into 4 groups (n = 4, each). Each group was given either 0.1, 0.25, 0.5, or 1.0 ml/kg of ipecac syrup, and the latency and numbers of retching and vomiting were recorded. Animals given an equal volume of saline served as controls. The numbers of vomiting and retching increased dose-dependently in both dogs and ferrets, and there was no difference in latency and numbers of vomiting between them. The numbers of retching were greater in ferrets than in dogs at > or = 0.25 ml/kg. Taking these results into consideration, the ferret seems to be as useful as the dog in studies on emetic effects of ipecac syrup.

p16INK4, pRB, p53 and cyclin D1 expression and hypermethylation of CDKN2 gene in thymoma and thymic carcinoma

There have been few reports on genetic alterations in thymomas. To investigate the expression of p16INK4A, RB, p53 and cyclin D1 in thymomas, we first examined 36 thymomas (non-invasive type, 16 cases; invasive type, 20 cases) and 3 thymic carcinomas, using immunohistochemistry. Abnormal expression of p16INK4A, RB, p53 and cyclin D1 was observed in 18, 8, 10 and 7 cases, respectively. Only a subgroup of invasive thymomas and thymic carcinomas showed an inverse correlation between p16INK4A and RB expression. Subsequently, we examined the 36 thymomas and 4 thymic carcinomas for mutations in p53 and CDKN2 genes, using PCR-SSCP and direct-sequencing analyses. No mutation of these genes was detected in the thymomas and thymic carcinomas examined. A polymorphism in the 3' untranslated region of exon 3 of CDKN2 was detected in 5 cases of thymoma. We searched for hypermethylation in the promoter region of CDKN2, observing it in 4 thymomas and 1 thymic carcinoma. Our data suggest that, unlike other more common cancers, alteration of the p53 gene may not play a significant role in the tumorigenesis of thymoma. However, inactivation of p16INK4A and RB may play a role in the progression of thymoma and thymic carcinoma.

Involvement of Ca(2+)-calmodulin-dependent protein kinase II in the intestinal secretory action of Escherichia coli heat-stable enterotoxin II

Treating the mouse intestine with the calmodulin antagonist W-7 and KN-93, an inhibitor of Ca(2+)-calmodulin-dependent protein kinase II (CaMK II), reduced the sensitivity of the host to the action of Escherichia coli heat-stable enterotoxin II (STII). CaMK II activity in mouse intestinal cells increased after exposure to STII. These results indicate that CaMK II is involved in the mechanism of action of STII.

Effects of 6-chloro-2',3'-dideoxyguanosine (6-Cl-ddG) in surface lymph nodes of rhesus monkeys (Macaca mulatta) chronically infected with simian immunodeficiency virus (SIVmac239)

We studied the effects of 6-chloro-2',3'-dideoxyguanosine (6-Cl-ddG), an antiretroviral drug, in surface lymph nodes of rhesus monkeys (Macaca mulatta) chronically infected with simian immunodeficiency virus (SIV). The rhesus monkeys were treated with 25 mg/kg of 6-Cl-ddG every 8 hr for 2 weeks. We performed sequential biopsies of the surface lymph nodes three times: before, during, and after the drug treatment. The 6-Cl-ddG dramatically decreased the number of infectious virus (measured by limiting dilution assay) in lymph node mononuclear cells. This decrease was consistent with the decrease in the number of viral RNA-positive cells in lymph nodes (analyzed by in situ hybridization). Histopathological analysis revealed that hyperplastic lymphoid follicles were reduced in size, especially, enlarged areas of centroblasts in lymphoid follicles (the so-called dark areas of germinal centers) were declined. Our results demonstrated that 6-Cl-ddG decreased the viral burden concomitantly with reduced hyper-activation of germinal centers in lymphoid follicles of SIV-infected rhesus monkeys.

The effects of dexamethasone on antiemetics in female patients undergoing gynecologic surgery

This randomized, double-blind study compared the effects of dexamethasone plus either droperidol, metoclopramide, or granisetron with each antiemetic alone for preventing postoperative nausea and vomiting (PONV) in 270 female patients undergoing general anesthesia for major gynecological surgery. Patients were randomly assigned to receive either droperidol 1.25 mg (Group D1, n = 45), droperidol 1.25 mg plus dexamethasone 8 mg (Group D2, n = 45), metoclopramide 10 mg (Group M1, n = 45), metoclopramide 10 mg plus dexamethasone 8 mg (Group M2, n = 45), granisetron 40 micrograms/kg (Group G1, n = 45), or granisetron 40 micrograms/kg plus dexamethasone 8 mg (Group G2, n = 45) immediately before the induction of anesthesia. A standard general anesthetic technique and postoperative analgesia were used throughout the study. Complete response, defined as no PONV and no administration of rescue antiemetic medication during the first 24 h after anesthesia, was 49% in Group D1, 60% in Group D2 (P = 0.199 versus Group D1), 51% in Group M1, 62% in Group M2 (P = 0.198 versus Group M1), 80% in Group G1, and 96% in Group G2 (P = 0.025 versus Group G1). Our results suggest that dexamethasone enhances the antiemetic efficacy of granisetron but does not potentiate the other antiemetics-droperidol and metoclopramide-in female patients undergoing major gynecological surgery.

IMPLICATIONS

We compared the efficacy of dexamethasone plus three different antiemetics-droperidol, metoclopramide, and granisetron-for the prevention of nausea and vomiting after gynecologic surgery. The granisetron-dexamethasone combination was the most effective for preventing post-operative emetic symptoms.

Cardiovascular responses to tracheal extubation or LMA removal in normotensive and hypertensive patients

PURPOSE

This study was undertaken to evaluate the haemodynamic changes of tracheal extubation or removal of a laryngeal mask airway (LMA) in normotensive and hypertensive patients.

METHODS

In a randomized trial of normotensive and hypertensive patients (n = 40 of each), tracheal extubation or LMA removal was performed. Changes in heart rate (HR), mean arterial pressure (MAP) and rate-pressure product (RPP) were measured before and 1, 2, 3, 5, and 10 min after tracheal extubation or LMA removal.

RESULTS

In normotensive patients, HR, MAP and RPP increased following tracheal extubation or LMA removal, and remained elevated for a maximum three minutes (P < 0.05). In hypertensive patients, the haemodynamic increases in response to extubation or LMA removal were observed for up to five minutes (P < 0.05). The immediate cardiovascular responses to extubation were greater than those related to LMA removal in both normotensive and hypertensive patients (normotensive: HR; 95 +/- 14 vs 81 +/- 11, MAP; 124 +/- 18 vs 106 +/- 10, RPP; 14,951 +/- 2720 vs 10,654 +/- 1898, hypertensive: HR 105 +/- 10 vs 87 +/- 13, MAP; 146 +/- 17 vs 119 +/- 12, RPP; 20,492 +/- 1674 vs 12,862 +/- 2115, mean +/- SD, P < 0.05). Following extubation or LMA removal, these haemodynamic variables increased more markedly in hypertensive patients than in normotensive patients (P < 0.05).

CONCLUSION

Removal of LMA is associated with less cardiovascular change than tracheal extubation in both normotensive and hypertensive patients.

Effective dose of granisetron in the reduction of nausea and vomiting after breast surgery

BACKGROUND

Prophylactic use of granisetron, a selective 5-hydroxytryptamine type 3 receptor antagonist, reduces the incidence of nausea and vomiting after breast surgery. This study was undertaken to determine the minimum effective dose of granisetron in the reduction of postoperative nausea and vomiting (PONV) in patients undergoing general anaesthesia for breast surgery.

METHODS

In a randomized, double-blind manner, 120 female patients aged 42-66 years were assigned to receive either placebo (saline) or granisetron in a dose of 20 micrograms.kg-1, 40 micrograms.kg-1 and 80 micrograms.kg-1 i.v. immediately before the induction of anaesthesia. A standard general anaesthetic technique was employed throughout. The PONV and safety assessments were performed continuously during the first 24 h after anaesthesia.

RESULTS

There were no significant differences among the groups with regard to patient demographics, surgical procedures, anaesthetics administered and analgesics given. The incidence of PONV was 47%, 43%, 17% and 17% after administration of placebo and granisetron 20 micrograms.kg-1, 40 micrograms.kg-1 and 80 micrograms.kg-1, respectively. Granisetron 40 micrograms.kg-1 was as effective as 80 micrograms.kg-1 and both resulted in significant reductions of the incidence of PONV compared with placebo and granisteron 20 micrograms.kg-1 (P < 0.05). No differences in the incidence of adverse events were observed among the groups.

CONCLUSION

Granisetron 40 micrograms.kg-1 appears to be the minimum effective dose for reducing PONV in patients undergoing general anaesthesia for breast surgery.

Concomitant cardiac and pulmonary operation. Pulmonary mechanics and outcome of phrenic nerve injury

OBJECTIVE

We describe the postoperative respiratory failure due to the phrenic nerve injury in the setting of concomitant cardiac and pulmonary operation.

EXPERIMENTAL STUDY

Prospective study.

SETTING

Department of Cardiac and Thoracic Surgery Osaka University Medical School.

PATIENTS AND INTERVENTIONS

From January 1984 to December 1993, 5 patients (1.4%) underwent the concomitant cardiac and pulmonary operation out of 359 patients who received surgical treatment for lung cancer at our institution.

MEASURES AND RESULTS

Three (60%) out of 5 patients required prolonged mechanical ventilation despite the absence of cardiac complication, lung edema or pneumonia. Diaphragm function and work of breathing were measured in two patients before and after weaning from mechanical ventilation. Phrenic nerve dysfunction was consistent with the result that trans-diaphragmatic pressure (delta Pdi) was low, a ratio of gastric to esophageal pressure swing (delta Pga/delta Pes) was abnormally negative, and work of breathing (WOB) was high. Phrenic nerve function restored associated with clinical improvement.

CONCLUSIONS

Diaphragm dysfunction and an increase in work of breathing may be potential causes of respiratory failure in patients after concomitant cardiac and pulmonary operation. This compromise in respiratory mechanics should not be overlooked in the postoperative care, which may lead to the best management in postoperative respiratory care.

Granisetron reduces the incidence of nausea and vomiting after middle ear surgery

We studied the efficacy of granisetron, a selective 5-hydroxytryptamine type-3 receptor antagonist, in preventing postoperative nausea and vomiting (PONV) after middle ear surgery. In a randomized, double-blind, placebo-controlled study, 60 ASA I patients received placebo (saline) or granisetron 40 micrograms kg-1 i.v. immediately before induction of anaesthesia (n = 30 in each group). A standard general anaesthetic technique was used. During the first 24 h after anaesthesia, the incidence of PONV in patients who had received granisetron was lower than in those who had received placebo (17% vs 63%; P < 0.05). There were no clinically important adverse effects in either group. We conclude that granisetron, given before anaesthesia, reduced the incidence of PONV after middle ear surgery.

Cloning and crystal structure of hematopoietic prostaglandin D synthase

Hematopoietic prostaglandin (PG) D synthase is the key enzyme for production of the D and J series of prostanoids in the immune system and mast cells. We isolated a cDNA for the rat enzyme, crystallized the recombinant enzyme, and determined the three-dimensional structure of the enzyme complexed with glutathione at 2.3 A resolution. The enzyme is the first member of the sigma class glutathione S-transferase (GST) from vertebrates and possesses a prominent cleft as the active site, which is never seen among other members of the GST family. The unique 3-D architecture of the cleft leads to the putative substrate binding mode and its catalytic mechanism, responsible for the specific isomerization from PGH2 to PGD2.

[Effects of calcium supplementation using AAACa or milk on nocturnal bone resorption in young women]

In order to study the effect of calcium supplementation on bone resorption, a randomized controlled crossover study was carried out on eight healthy 18-19 year old female volunteers using either AAACa heated oyster shell with vacuum-heated seaweed or milk. Regimen A consisted of an oral dose of 200 mg calcium in the form of AAACa. B 200 ml milk after breakfast and supper and at bedtime, and C control with no calcium supplement. Early morning fasting blood and urine sampling was carried out after 7 days of calcium supplementation. Serum calcium was higher in groups A and B than in C, and serum intact parathyroid hormone (PTH) was significantly lower in group A than in groups B and C, according to a paired t-test. Urinary excretion of crosslinked collagen degradation product, pyridinoline and deoxypyridinoline showed a similar decrease in groups A and B but not in C. The more effective suppression of PTH by AAACa than by milk may be due to its higher bioavailability and the absence of phosphate stimulating PTH secretion.

Phosphorylation of the Sendai virus M protein is not essential for virus replication either in vitro or in vivo

A large proportion of intracellular Sendai virus (SeV) M proteins is phosphorylated, but in mature virions the M protein is not phosphorylated or dephosphorylated. Phosphorylated M protein in cells is bound to the cytoskeletal components more firmly than unphosphorylated M protein. Thus it has been hypothesized that M protein phosphorylation plays an important role in the virus life cycle, especially in the step of maturation. Here, a transient expression-mutation experiment of the M gene demonstrated that a change of the Ser residue at the 70th position from the N-terminus to Ala (S70A) totally abolished M protein phosphorylation, strongly suggesting that this residue is phosphorylated. The mutated M gene was then placed in the corresponding region in the cDNA plasmid which generates a full-length antigenome SeV RNA, and a mutant SeV M-S70A was successfully recovered from the cDNA. This mutant virus was indeed defective in M protein phosphorylation but did not differ at all from the wild-type SeV recovered from the parental cDNA either in the replication kinetics and plaque morphology in cultured cells or in in vivo replication and pathogenicity for mice. We thus concluded that no phosphorylation of the M protein was required for SeV replication either in vitro or in vivo.