Cerebral oxygen supply and utilization during infant cardiac surgery

The survival of infants with congenital heart disease has improved dramatically. However, the incidence of neurological injury in infants surviving cardiac surgery remains considerable. These neurological sequelae are attributable at least in part to hypoxia-ischemia/reperfusion, which inevitably accompanies infant heart surgery with deep hypothermia, cardiopulmonary bypass, and circulatory arrest. To begin to identify mechanisms of brain injury during infant cardiac surgery, we used near-infrared spectroscopy to study the relationship between cerebral intravascular (hemoglobin) and mitochondrial (cytochrome aa3) oxygenation in 63 infants (aged 1 day to 9 months) undergoing deep hypothermic repair of congenital heart defects, throughout the intraoperative period. Moreover, we assessed the effect of postnatal age on these changes. The cerebral concentration of oxidized cytochrome aa3 decreased from the onset of deep hypothermic cardiopulmonary bypass, despite apparent abundant intravascular oxygenation manifested by a simultaneous increase in the cerebral concentration of oxyhemoglobin. During this interval infants older than 2 weeks had a greater decrease in oxidized cytochrome aa3 than did infants 2 weeks old or younger. During deep hypothermic circulatory arrest, cerebral levels of oxidized cytochrome aa3 remained depressed while those of oxyhemoglobin declined. With reperfusion following circulatory arrest, the recovery of oxidized cytochrome aa3 was delayed, despite a rapid recovery of intravascular oxygenation (HbO2). After rewarming and 60 minutes of reperfusion, only 46% of infants recovered to the baseline level of cerebral oxidized cytochrome aa3. These findings demonstrate a paradoxical dissociation of changes in intravascular and mitochondrial oxygenation during hypothermic cardiopulmonary bypass; a pronounced decrease of mitochondrial oxygenation is established during induction of hypothermia and a delay in recovery of mitochondrial oxygenation occurs following circulatory arrest. These effects were more pronounced in infants older than 2 weeks than in younger infants. The data suggest potentially deleterious impairments of intrinsic mitochondrial function or of delivery of intravascular oxygen to the mitochondrion or both, effects previously undetected and apparently influenced by cerebral maturation.

Reduction of cytochrome aa3 measured by near-infrared spectroscopy predicts cerebral energy loss in hypoxic piglets

Near-infrared spectroscopy is a noninvasive monitoring technique that allows quantitative measurement of changes in cerebral oxygenated Hb (HbO2), deoxygenated Hb (Hb), total Hb, and oxidized cytochrome aa3 (CytO2). Changes in cerebral Hb oxygenation and CytO2 have been measured in human neonates and infants under a variety of conditions. However, the association of these measurements with cerebral high-energy phosphate loss is not known. We studied simultaneous changes in cerebral HbO2, Hb, total Hb, and CytO2 by near-infrared spectroscopy and changes in nucleoside triphosphate (NTP, mostly ATP) and phosphocreatine (PC) concentrations and intracellular pH by in vivo 31P-labeled magnetic resonance spectroscopy. Four-wk-old piglets (n = 8) underwent sequential hypoxic episodes of increasing severity (inspired O2 concentration, 12, 8, 6, 4, and 0%). Animals were anesthetized and mechanically ventilated. At all levels of hypoxia, cerebral HbO2 decreased, and Hb increased. Loss of PC or NTP was not observed until inspired O2 concentration was decreased to less than 12%. With such severe hypoxia, hypotension, intracellular acidosis, and increasingly severe PC and NTP depletions occurred. Decreases in PC and NTP correlated closely with decreased CytO2 and arterial blood pressure (p < 0.0001) but not with changes in HbO2 and Hb. In conclusion, cerebral hypoxemia is readily detected by near-infrared spectroscopy as a decrease in HbO2 and an increase in Hb. However, relative changes in cerebral HbO2 and Hb have low predictive value for cerebral energy failure. Reduction of CytO2 is highly correlated with decreased brain energy state and may indicate impending cellular injury.

A sulfated chitin, SCM-chitin III, inhibits the clearance of human erythrocytes from the blood circulation in erythrocyte-transfused SCID mice

Recently, we have developed a SCID mouse model in which circulating red blood cells (RBC) are entirely substituted with RBCs from other animals like bovine (Bo) or human (Hu). The relatively short life time, especially of Hu-RBCs, in the SCID mouse, however, is a major obstacle in this model. The present study was performed to examine whether a low-toxic sulfated chitin, carboxymethyl chitin III (SCM-chitin III), which has heparin-like structures in the molecule (heparinoid), could inhibit the Hu-RBC clearance in RBC-transfused SCID mice. When Hu-RBCs were transfused simultaneously with SCM-chitin III, their life time in the blood circulation was prolonged significantly. Sulfated chitosan (S-chitosan) showed only a weak decelerating activity on the clearance of Hu-RBCs. Carboxymethyl chitin (CM-chitin), which was used as an unsulfated control compound, had no effect on the Hu-RBC clearance. Another sulfated polysaccharide, dextran sulfate, though this showed some adverse effects, such as anti-coagulant and anti-platelet aggregation, also exhibited a potent decelerating activity on Hu-RBC clearance. Clearance deceleration by these sulfated polysaccharides was primarily attributable to the inhibition of RBC uptake by cultured macrophages.

No effect of RU 486 (mifepristone) on hepatocellular tumorigenesis in orchiectomized male mice induced by 3'-methyl-4-dimethylaminoazobenzene

Effects of RU 486 (mifepristone) on hepatocellular tumorigenesis in orchiectomized male mice induced by 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB) were investigated. Male mice that had been treated with 3'-Me-DAB neonatally were orchiectomized at one month of age, and injected daily with vehicle only or RU 486 at 0.2 or 0.4 mg/day thereafter. In the liver of orchiectomized males injected with vehicle only, adenomatous nodules developed at incidences of 16.2 and 38.5% at 9 and 12 months of age, respectively, but no carcinomas developed at these ages. Injections of RU 486 at 0.2 or 0.4 mg/day neither affect incidences of adenomatous nodules in the liver, their numbers per mouse, and their areas, nor promote the development of carcinomas. The present results suggest that the long term administration of RU 486 has no effects on hepatocellular tumorigenesis.

Establishment of a SCID mouse model having circulating human red blood cells and a possible growth of Plasmodium falciparum in the mouse

Our previous study has demonstrated that repeated transfusions of bovine red blood cells (RBCs) into SCID mice resulted in a complete substitution of their circulating RBCs. Identical experiments with human (Hu) RBCs, however, gave rise to a poor RBC-substitution because of the rapid elimination of Hu-RBCs from the circulation of SCID mice. Search for substances to decelerate the Hu-RBC clearance picked up some effective polysaccharides, such as sulfated chitin and mannan, but they were not effective enough to achieve a high level of Hu-RBC-substitution. In the present study, we found that Hu-serum significantly extended the lifetime of Hu-RBC in SCID mice and that repeated transfusions of the mice with Hu-RBCs, in combination with Hu-serum administration, resulted in an almost complete substitution of their circulating RBCs. An Hu-RBC-substituted SCID mouse inoculated with Plasmodium falciparum had a parasitemia persisting for two weeks, indicating a possible growth of this parasite in the mouse. Thus, this report gave the first demonstration of a complete substitution of the circulating RBCs in SCID mice with Hu-RBCs and of a successful P. falciparum infection in the mice.

Serum from Theileria sergenti-infected cattle accelerates the clearance of bovine erythrocytes in SCID mice

Anemia is a major clinical sign of Japanese bovine theileriosis caused by Theileria sergenti. To investigate the possible factors causing anemia in cattle, we developed a clearance test for bovine erythrocytes (Bo-RBC) in severe combined immunodeficient (SCID) mice. Clearance of Bo-RBC in the SCID mice was significantly accelerated when the mice were inoculated with a serum sample obtained from an infected calf during a highly parasitized phase but not when they were injected with a serum sample obtained during the convalescence phase. Acceleration of the clearance of Bo-RBC was also observed in mice treated with merozoite extract. Furthermore, the clearance of Bo-RBC that had been treated with merozoite extract was accelerated. A significant hemolytic activity in infected serum (highly parasitized phase) was observed. Activities sufficient to accelerate the clearance of Bo-RBC in SCID mice and to induce in vitro hemolysis of Bo-RBC were also observed with a merozoite extract from T. sergenti. The results suggest a possible linkage between the in vitro hemolysis of Bo-RBC and the acceleration of Bo-RBC clearance in SCID mice.

Cholesteryl ester transfer protein gene: two common mutations and their effect on plasma high-density lipoprotein cholesterol content

Cholesteryl ester transfer protein regulates high-density lipoprotein cholesterol (HDL-C) level, and genetic deficiency causes hyperalphalipoproteinemia (HALP). The G to A mutation in the intron 14 splice donor (I14A) has been known to be a common mutation in HALP. Recently, another mutant, D442G (Asp 442 to Gly), was ascertained. The allelic frequencies of I14A and D442G were investigated using 226 unrelated patients with HDL-C of 1.03 mmol/L (40 mg/dL) or greater. Of these, 44 had a mutation I14A and/or D442G. The I14A was found in 15, including 4 compound heterozygotes (I14A/D442G) in patients with HDL-C of 2.05 mmol/L (80 mg/dL) or greater. All I14A homozygotes (n = 5) were present in the group with HDL-C of 3.08 mmol/L (120 mg/dL) or greater, and the allelic frequency paralleled the increase in HDL-C level. D442G was identified in 33, including the 4 compound heterozygotes. Its allelic frequency appeared as two clusters, one at HDL-C around 1.79-2.03 mmol/L (70-79 mg/dL) and the other at HDL-C of 2.82 mmol/L (110 mg/dL) or greater; the latter consisted exclusively of compound heterozygotes. Allelic frequency in the general population for I14A and D442G was 0.81% and 4.62%, respectively. These data suggest that D442G is a common mutation and that, although I14A is responsible for the most severe HALP, D442G leads to a relatively smaller increase in HDL-C.

Transfusion with xenogeneic erythrocytes into SCID mice and their clearance from the circulation

We have previously demonstrated that the red blood cells (RBCs) in the blood circulation of SCID mice could be almost completely substituted with bovine RBCs by means of repeated transfusions. In the present study, transfusion experiments were carried out with RBCs from various animal species to investigate the ability of SCID mice to accept xenogeneic RBCs. Bovine (Bo), equine (Eq), human (Hu) and murine (Mu) RBCs were labeled with a fluorescent dye to trace their trafficking in the blood stream. Following the intravenous injection these RBCs were cleared from the circulation at various rates; the 1/100 reduction time in the labeled cell counts was 2 to 7 days, 4 to 7 hr and 1 to 2 hr with Bo-, Hu- and Eq-RBCs, respectively. In contrast, labeled Mu-RBCs from not only syngeneic but also allogeneic mouse strain were able to stay over 50 days. The difference in clearance rates was attributable to the difference in uptake of the RBCs by the splenic macrophages. The clearance rates of labeled RBCs were significantly decreased by co-transfusion with unlabeled RBCs of the same species, indicating that xenogeneic RBCs were recognized by the reticulo-endothelial system of SCID mice in a species-specific fashion. Furthermore, at least in the case of Hu-RBC, the complement component 3 may play a role in the Hu-RBC clearance in SCID mice since C3 deposition was observed on Hu-RBCs but not on Bo- and Eq-RBCs.

Detection of antibodies to Anisakis simplex larvae by enzyme-linked immunosorbent assay and immunoelectrophoresis using crude or purified antigens

The enzyme-linked immunosorbent assay (ELISA) and immunoelectrophoresis (IEP) were used for the serodiagnosis of larval Anisakis simplex infections in man and immunized rabbits. Sephacryl S-300 gel filtration was used for separating crude antigen. Four fractions were obtained. Sera from patients with other helminth infections sometimes cross reacted with Anisakis larval antigens. With IEP, crude antigen is more sensitive than purified antigens. With ELISA, the third fraction is the most sensitive for detecting antibodies to Anisakis larvae in the sera of humans and immunized rabbits.

Trilineage recovery by combination therapy with recombinant human granulocyte colony-stimulating factor and erythropoietin in patients with aplastic anemia and refractory anemia

Ten patients with aplastic anemia (AA) and seven patients with refractory anemia (RA) were treated with recombinant human granulocyte colony-stimulating factor (rhG-CSF) and erythropoietin (rhEpo) in combination. rhG-CSF (5-20 micrograms/kg) and rhEpo (120-720 U/kg) were administered by s.c. injection three times a week for at least six months, and the administration was continued as maintenance therapy for as long as possible when hematological responses were observed. Six (60%) of the ten AA patients and four (58%) of the seven RA patients showed multilineage responses. Of these responders, six patients achieved trilineage recovery. While all of the responders were dependent on red blood cell transfusions and eight of them required platelet transfusions before treatment, they now no longer need transfusions of either red blood cells or platelets. A median treatment duration of 9 (range 1 to 28) months was required to achieve multilineage recovery. The responders showed an ability to maintain the multilineage recovery for 9+ to 47+ months and to tolerate long-term treatment. These results indicate that the long-term treatment with rhG-CSF and rhEpo may benefit a substantial percentage of patients with AA and RA and provide an optional therapy for these patients.

Effect of mesenchymal glandular inductors on the growth and cytodifferentiation of neonatal mouse seminal vesicle epithelium

To investigate the developmental properties of glandular mesenchymal inductors along the cranial-caudal extent of the developing male urogenital tract, neonatal mouse seminal vesicle epithelium (SVE) was combined with mesenchyme of the seminal vesicle (SVM), urogenital sinus (UGM), bulbourethral gland (BUG-M), or bladder (BLM) and grafted under the renal capsule of adult syngeneic or athymic male mice. Both SVM + SVE and UGM + SVE tissue recombinants expressed SV histogenesis and SV secretory proteins. BUG-M + SVE recombinants exhibited extensive growth as evidenced by a 36-fold increase in wet weight and a 27-fold increase in DNA content; however, the glandular structures that were induced in the SVE lacked the convoluted mucosa typical of SV. Furthermore, neither SV nor prostatic secretory proteins were detected in these recombinants. SVE grown in association with BLM failed to develop altogether. Thus, the ability to promote SV histogenesis and function is distinctly different in mesenchyme of cranial (SVM and UGM) versus caudal (BUG-M) regions. This implies the existence of a glandular inductive field in the developing male urogenital tract within which inductive activity varies regionally.

[A case of benign epilepsy of children with centro-temporal EEG foci with multiple arachnoid cysts]

An 8-year-old boy with benign epilepsy of children with centro-temporal EEG foci (BECCT) with multiple arachnoid cysts was reported. He had febrile convulsions 3 times, for a few minutes each time, at the age of 7 months, and thereafter had generalized tonic-clonic convulsions of 2 minute duration twice in 2 days without fever. EEG showed spike & wave complexes predominantly in the right central area. CT revealed arachnoid cysts in the right temporal lobe and cerebellar hemisphere, and left frontal and central sulci. He has been treated with carbamazepine without neurosurgical operation for the arachnoid cysts, and no seizure has occurred besides a single episode at the age of 3 years. Only 3 cases of BECCT with arachnoid cysts have been reported in the literature. Two of these cases underwent neurosurgical operations for arachnoid cysts, but the operations led to improvement in neither the clinical course nor EEG findings. It is suggested that arachnoid cysts do not lead to poorer prognosis in a patient with BECCT.

A schizophrenic patient who developed extreme hypothermia after an increase in the dose of haloperidol: a case report

A patient with chronic schizophrenia, who had been treated for a long time with chlorpromazine, haloperidol, levodopa, benserazide hydrochloride, diazepam and biperiden, developed extreme hypothermia (about 32 degrees C) when the dose of haloperidol was increased because of a deterioration of the patient's mental symptoms. No other physical manifestations were observed, except bradycardia. The turnover of noradrenaline in the cerebrospinal fluid and blood was increased in association with the hypothermia in this patient. A hypothesis about the involvement of monoamine imbalance in changes in body temperature is discussed.

Pressure gradients between intraluminal and extraluminal spaces may affect the potassium induced contraction in the rabbit's basilar arteries

In order to investigate the different contactile effects between intraluminal and extraluminal vasoactive agents, we studied the contractile responses of rabbit basilar artery to selective intraluminal and extraluminal administration of potassium, serotonin and histamine in vitro. We also studied how the physical pressure gradients, such as hydrostatic or osmotic pressure gradients between intraluminal and extraluminal spaces, affect potassium-induced contraction. Intraluminal potassium (30 mM) induced a significantly greater contraction than extraluminal potassium. Serotonin (2 x 10(-7) M) and histamine (10(-5) M) applied intraluminally caused the same magnitude of the contraction as those applied extraluminally and no significant differences were noted between these applications. These differences in potassium-induced contraction were more significant when the intraluminal hydrostatic pressure was elevated by 20 mmHg. Contraction by either intraluminal or extraluminal potassium was significantly decreased when intraluminal pressure was raised by 40 mmHg. As the osmotic pressure gradients between the extraluminal and the intraluminal spaces were increased, these differences in potassium-induced contraction were decreased. Our findings suggest that physical pressure gradients may affect potassium-induced contraction in a different manner from pharmacologically-induced contraction and that free ions can penetrate the vascular wall by physical pressure gradients between the intraluminal and extraluminal spaces of cerebral artery.

Inhibitory effect of sialoadenectomy on hepatocellular tumourigenesis in male mice induced by 3'-methyl-4-dimethylaminoazobenzene

Male C57BL/6xDS-F1 mice that had been treated with 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB) neonatally were subjected to sialoadenectomy (removal of the submandibular salivary glands) 60 days after birth. The development of adenomatous nodules and carcinomas in the livers of these mice was compared with the livers of males without sialoadenectomy. The incidence of adenomatous nodules in sialoadenectomized males at 6, 8, 10, and 12 months was significantly lower than that in sham-operated animals. Carcinomas were found in the livers of both sham-operated and sialoadenectomized males that were 10 and 12 months old and were less frequent in sialoadenectomized males although the difference was significant only at the age of 12 months. Sialoadenectomy decreased the serum concentration of epidermal growth factor (EGF) by about 40%. The present results indicate that sialoadenectomy inhibits the development of hepatocellular tumours induced by 3'-Me-DAB in male mice, an effect which may be caused by decrease in the serum level of EGF.

Artificial fiber complexes composed of cellulose and guar gum or psyllium may be better sources of soluble fiber for rats than comparable fiber mixtures

Three fiber complexes composed of cellulose and the same weight of guar gum, cornstarch or psyllium were constructed as three-dimensional networks of cellulose fiber filled with the soluble components. Physiological properties of these fiber complexes were examined in comparison with a mixture of powdered cellulose and the corresponding polysaccharides at a ratio of 1:1 in rats. Another group of rats was fed a fiber-free diet. Body weight gain in the guar gum-cellulose mixture group, but not in guar gum-cellulose complex group, was lower than that of the fiber-free group. The cecal walls in the groups fed the guar gum-cellulose and psyllium-cellulose mixture diets were heavier than those in the corresponding fiber complex-fed groups. Weights of the small intestinal wall and ileal mucosa were also greater in the guar gum-cellulose mixture-fed group than in the guar gum-cellulose complex-fed and the fiber-free diet-fed groups. Fermentable energy in dietary fiber estimated from fecal energy excretion, short-chain fatty acid contents and in vitro short-chain fatty acid production rates in the cecum of the complex-fed groups were similar to those in the fiber mixture-fed groups. However, butyric acid content and production rate in the group fed the guar gum-cellulose complex were markedly higher than in the other groups. The lowering effects of guar gum-cellulose and psyllium-cellulose mixtures on plasma cholesterol concentration tended to be greater than those of guar gum-cellulose and psyllium-cellulose complexes. These findings demonstrate that the artificial fiber complexes supply soluble fibers without increasing mechanical stress to the intestines and decreasing cecal fermentation.

[A case of subperitoneal tuberculosis revealed by abdominal pain during pulmonary tuberculosis treatments]

The case was a 58 year-old female. During hospitalization for the treatment of pulmonary tuberculosis, she complained of pain in the left hypochondriac region. Abdominal CT revealed a mass between the abdominal wall and left lobe of the liver. Metastatic liver carcinoma was suspected by aspiration cytology, but no primary tumor could be identified. Therefore, an exploratory laparotomy was done, and the mass proved to be a subperitoneal tuberculoma. Tuberculous lymphadenitis was also found in lymph nodes of the upper abdominal cavity. Tuberculosis in the abdominal cavity has been rare in recent times in Japan. Therefore, this case provides valuable experience in the differential diagnosis of an abdominal mass.

[Empiric therapy with fluconazole in granulocytopenic patients with carcinoma or leukemia]

We performed a randomized clinical trial in granulocytopenic patients with carcinoma or leukemia. Patients with persistent fever for more than 2 days despite antibiotic therapy were randomized to antibiotic plus fluconazole therapy group (FLCZ group) or antibiotic therapy only group (antibiotic group) by the envelope method. It was possible to evaluate clinical efficacies in 62 patients (37 patients in FLCZ group and 25 patients in antibiotics group). In patients whose neutrophil counts were less than 100/microliters on the initial day of therapy, clinical efficacy rates were 72.0% (18/25) in FLCZ group and 57.1% (8/14) in antibiotics group. In patients whose neutrophil counts continued to be less than 100/microliters during therapy, clinical efficacy rates were 64.3% (9/14) and 50.0% (3/6), respectively. Further, in patients whose neutrophil counts continued to be less than 500/microliters during therapy, they were 76.9% (20/26) and 53.3% (8/15), respectively. No severe side effects nor severe case of abnormal change in laboratory test values due to fluconazole were observed in this trial. These data suggest that empiric antifungal therapy with fluconazole is effective for fungal infections in granulocytopenic patients with carcinoma and leukemia.

A family with complete deficiency of plasma cholesteryl ester transfer protein activities

A 43-year-old male with a high value of high density lipoprotein cholesterol (151 mg/dl) was found among subjects receiving annual health checks. We investigated the cholesteryl ester transfer protein (CETP) activity and conducted a family study. There was complete deficiency of CETP activities in the proband and his sister, and partial deficiency of CETP activities in his mother and daughter. Genetic analysis revealed a splicing defect (G to A point mutation) in intron 14 of the CETP gene.

5 alpha-reductase activity in developing urogenital tracts of fetal and neonatal male mice

5 alpha-Reductase activity in testes and urogenital tract tissues from male mice at 14.5 days gestation and 0 days of age (birth) was assessed by measurement of metabolites of testosterone released into the medium in a serum-free culture system. In male mice at 14.5 days gestation, the testis and the cranial portion of the urogenital ridge (UGR), which develops into the epididymis, had little 5 alpha-reductase activity. The caudal portion of the UGR, which develops into the seminal vesicle (SV), and the cranial portion of the urogenital sinus (UGS) had 12-fold higher activity than the cranial portion of the UGR. 5 alpha-Reductase activity in the middle portion of UGR was intermediate between that of its cranial and caudal portions. The highest levels of 5 alpha-reductase activity were detected in the caudal portion of UGS, even though this higher value was not significantly different from those in the caudal UGR or the cranial UGS. In 0-day-old male mice, 5 alpha-reductase activity of testis remained low at a level similar to that observed at 14.5 days gestation. The epididymis also exhibited low 5 alpha-reductase activity in 0-day-old mice, even though this activity had increased 2.2-fold relative to that observed in the cranial UGR at 14.5 days gestation. 5 alpha-Reductase activity of the cranial portion of UGS (prostatic rudiment) was relatively high on day 0 and similar to that in the same region at 14.5 days gestation. The SV and bulbourethral gland (BUG) on day 0 had high 5 alpha-reductase activity, which had increased 1.4- and 1.3-fold, respectively, compared to their 14.5 day embryonic anlage, although the increase was not significant. Through examination of 5 alpha-reductase activity regionally in the developing urogenital tract, it is evident that the concept that testosterone is the active androgen during Wolffian development is overly simplified. The present study suggests the importance of spatial/regional factors in Wolffian duct development in regard to the role of dihydrotestosterone. 5 alpha-reductase activity in the caudal Wolffian duct (SV rudiment) equals or exceeds that in the developing prostate, and at birth, dihydrotestosterone production is virtually identical in the SV and prostate. This suggests that 5 alpha-reduced androgens play a prominent role in the development of SV.(ABSTRACT TRUNCATED AT 400 WORDS)

Inhibitory effects of transforming growth factor-beta 1 on androgen-induced development of neonatal mouse seminal vesicles in vitro

The effects of transforming growth factor-beta 1 (TGF beta 1) on the development of seminal vesicles (SVs) of neonatal mice were investigated in vitro. SVs from 0-day-old male mice were cultured for 2-8 days in serum-free, chemically defined medium with or without 5 alpha-dihydrotestosterone (DHT) at 10(-8) M in the presence or absence of TGF beta 1. Before culture, SVs from 0-day-old mice had no epithelial branches. SVs cultured in medium with DHT formed numerous epithelial branches after day 2 of culture, whereas epithelial branching did not occur in SVs cultured without DHT. The addition of TGF beta 1 (10 ng/ml) to DHT-containing medium almost completely inhibited the formation of epithelial branches. However, the removal of TGF beta 1 from DHT-containing medium on day 2 or 4 of culture initiated the formation of epithelial branches. TGF beta 1 (10 ng/ml) decreased [3H]thymidine labeling indices of both epithelium and mesenchyme of SVs cultured in medium with DHT during 8 days of culture, an effect that was reversed after the removal of TGF beta 1 from the medium on day 2 or 4 of culture. In contrast, TGF beta 1 (10 ng/ml) did not affect the labeling indices of either epithelium or mesenchyme of SVs cultured in medium without DHT. TGF beta 1 (10 ng/ml) also suppressed the normal increase in protein and DNA contents of SVs cultured in medium with DHT, whereas it did not reduce protein or DNA contents of SVs cultured in medium without DHT. The present study indicates that androgen-dependent growth of the SV can be reversibly inhibited by TGF beta 1, whereas androgen-independent growth of the SV is insensitive to TGF beta 1.

1 alpha-hydroxyvitamin D3 inhibits type II collagen-induced arthritis in rats

The effects of 1 alpha-hydroxyvitamin D3 and 24,25-dihydroxyvitamin D3 on Type II collagen-induced arthritis in rats, an experimental model of rheumatoid arthritis, were examined. Oral administration of 1 alpha-hydroxyvitamin D3 significantly suppressed the incidence of arthritis and inhibited hind paw swelling. The level of anti-Type II collagen antibodies was decreased in the 1 alpha-hydroxyvitamin D3 treated-group. In contrast, 24,25-dihydroxyvitamin D3, indomethacin, and gold had no effect on either the incidence of arthritis or the antibody levels. These findings demonstrate a beneficial effect of 1 alpha-hydroxyvitamin D3 on Type II collagen-induced arthritis in rats and indicate that it has an antirheumatic effect.

Gamma delta T cells contribute to immunity against the liver stages of malaria in alpha beta T-cell-deficient mice

The functional role of gamma delta T cells (expressing the gamma delta heterodimeric T-cell receptor for antigen) in infectious diseases remains largely unknown. We have therefore attempted to define the possible role of these T cells in the immune response against the various developmental stages of malaria parasites. For this purpose, we monitored the immune response and the development of liver and blood stages of Plasmodium yoelii, a rodent malaria parasite, in immunized and nonimmunized alpha beta T-cell-deficient and gamma delta T-cell-deficient mice. Immunization of alpha beta T-cell-deficient mice with irradiated sporozoites induced an immune response that significantly inhibited the development of the parasite's liver stages. This inhibitory immune response was abolished by an antibody-mediated transient in vivo depletion of gamma delta T cells. Two gamma delta T-cell clones were derived from malaria-immunized alpha beta T-cell-deficient mice. The adoptive transfer of one of these gamma delta T-cell clones to normal mice inhibited the development of liver stages, following sporozoite inoculation. These results provide evidence for gamma delta T-cell-mediated protective immunity against parasites, in the absence of alpha beta T cells. As for the blood phase of the infection, both normal mice and gamma delta T-cell-deficient mice cleared the blood stages of the nonlethal strain of P. yoelii, while alpha beta T-cell-deficient mice failed to control the parasitemia.