Hyperthermia-induced seizures in the rat pup: a model for febrile convulsions in children.

Seizures were produced in rat pups by ambient hyperthermia. Seizure threshold temperatures, measured rectally and intracerebrally, increased between 2 and 10 days of age. Electrocortical paroxysmal discharges were confirmed in hyperthermic 6- and 10-day-old pups. The increasing resistance to hyperthermic seizures with maturation and the electroencephalographic changes induced by hyperthermia are similar to those in young children.

Synovial fluid cell counts and its role in the diagnosis of paediatric septic arthritis.

PURPOSE: Clinical presentation of paediatric septic arthritis (SA) can be similar to other joint pathologies. Despite potential for infection in all major joints, most diagnostic criteria are based on values from the hip. This study identifies the best joint aspirate values in diagnosing SA in all joints. METHODS: In all, 166 patients who underwent 172 joint aspirations at the authors' institution between 01 September 2004 and 01 September 2014 were retrospectively identified. Recorded measures included age, sex, duration of symptoms, fever history, weight-bearing status, aspiration results, serum results and antibiotic administration. Patients were placed in the following four categories: 'culture confirmed SA' (C-SA), 'suspected SA' (S-SA), 'Other' and 'Other-rheumatologic' (Other-R), a subcategory of 'Other'. RESULTS: Most common sites of aspiration were the knee (55%) and hip (29%). Diagnostic grouping was as follows: C-SA = 44, S-SA = 45, Other = 83 (Other-R = 21). Fever and non-weight-bearing prior to admission were useful predictors of SA, though in C-SA patients, 21% did not have a fever and 23% could weight bear at the time of admission. Aspirate white blood cell (WBC) count was significantly greater in both C-SA (92 000 cells/hpf) and S-SA (54 000) than in Other (10 000) and Other-R (18 000) patients. The percentage of polymorphonuclear (%PMN) was also significantly greater in C-SA (81.1%) and S-SA (80.9%) than in Other (57.9%) and Other-R (63.3%). CONCLUSION: Joint aspirate values, especially %PMN, are valuable in diagnosing SA. Additionally, antibiotics pre-aspiration did not affect %PMN, facilitating subsequent diagnosis of infection. Lastly, while aspirate WBC count was a valuable indicator of SA, this finding is not as definitive as previous research suggests. LEVEL OF EVIDENCE: IV Case Series.

[Primary arterial switch operation for complete transposition of the great arteries (type I) of a neonate weighing 1,378 g].

A 2-day-old female baby, delivered by emergent cesarean section at 35 weeks of gestational age with a birth weight of 1,378 g, was referred to our institute for intensive care of heart failure. By echocardiography and cardiac catheterization, the patient was diagnosed with isolated complete transposition of the great arteries. Primary arterial switch operation was performed at 13 days of age. No technical difficulty arose, imposed by the small size of cardiovascular structure. On the 5th postoperative day, surgical repair of intestinal perforation was performed. Convalescence thereafter was uneventful. She returned home on the 64th postoperative day with the body weight of 2,310 g. We conclude that primary arterial switch operation can be a feasible surgical option even in a neonate with very low birth weight.

Renin in the rat pituitary coexists with angiotensin II and depends on testosterone.

In the rat pituitary gland, immunoreactive angiotensin II (ANG II), renin, and LH, but not PRL, were found within the same cells of the anterior pituitary gland by staining with the avidin-biotin complex method in adjacent sections. No renin-positive staining was observed in the pituitary of the rats after 10 days of castration, but positive staining reappeared after 8 weeks. This effect of castration on renin immunoreactivity was abolished by the simultaneous administration of testosterone. In contrast, ANG II immunoreactivity was unaffected by castration. The intensity of renin immunoreactivity in the pituitary was less prominent in the female than in the male rat. These results suggest that there exists a pituitary renin-angiotensin system localized in the gonadotrophs and that the pituitary renin is under androgenic control.

Synthetic rat atrial natriuretic factor inhibits in vitro and in vivo renin secretion in rats.

We investigated the action of a synthetic rat atrial natriuretic factor (ANF) with 28 amino acids on renin secretion in rats. Renin release by kidney cortex slices was determined after 90 min of incubation at 37C. ANF inhibited basal renin release in a dose-related fashion. ANF also decreased cAMP release and increased cGMP release in a dose-dependent manner. Renin release stimulated by 10(-7) M isoproterenol was inhibited by ANF with an ID50 of 5.8 x 10(-8) M. The renin-inhibitory effect was not calcium-dependent. In anesthetized rats, a bolus IV dose of ANF decreased plasma renin activity and cAMP concentration, but increased cGMP concentration. These data suggest that ANF inhibits renin secretion via the direct action on juxtaglomerular cells and that this effect may be partly mediated by the changes in cyclic nucleotide production.

Atrial natriuretic polypeptide inhibits cortisol secretion as well as aldosterone secretion in vitro from human adrenal tissue.

The effect of alpha-human atrial natriuretic polypeptide (ANP) on adrenal steroidogenesis was studied in human adrenal tissues obtained surgically from four patients with Cushing's syndrome due to an adrenal adenoma and five patients with an aldosterone-producing adenoma (APA). ANP significantly inhibited basal and ACTH (3.4 X 10(-8) M)-stimulated cortisol and aldosterone secretion in both the adenomas and adjacent adrenocortical tissues from patients with Cushing's syndrome. ANP inhibited ACTH-stimulated, but not basal, secretion of cortisol and aldosterone in the adjacent tissues from patients with APA. In addition, ANP significantly inhibited both basal and ACTH-, angiotensin II (10(-6) M)-, and potassium chloride (10 mM)-stimulated secretion of aldosterone from the adenomas of patients with APA. ANP-induced changes in cortisol and aldosterone secretion were accompanied by a decrease in cAMP and an increase in cGMP secretion. These results suggest that ANP may be a possible regulator of cortisol as well as aldosterone secretion in humans, and these effects might be due to concomitant alteration in cyclic nucleotide metabolism.

Evidence for the existence of des-Asp1-angiotensin II in human uterine and adrenal tissues.

Renin is present in various tissues outside the kidney. In contrast, the levels of angiotensins (ANG), the active products of the renin-angiotensin system, have not been thoroughly evaluated in tissues. In this study, we demonstrated the presence of immunoreactive (ir) ANG I and ANG II in various human tissues by RIA. Of the tissues examined, uterine tissue contained the most ir-ANG II. Since the anti-ANG II antibody used had significant cross-reactivity with ANG III, high performance liquid chromatography was performed to separate ANG II from ANG III. The major portion of the ir-ANG II in the plasma was ANG II. In contrast, the major portion of the ir-ANG II in uterine tissue was determined to be ANG III, a known biologically active peptide. The adrenal gland and testis also contained ANG III. From these results, it can be postulated that ANG III may contribute to the biological activity of ANG in some tissues.

Immunoreactive alpha-human atrial natriuretic polypeptide in human plasma.

A radioimmunoassay (RIA) has been developed for the determination of alpha-human atrial natriuretic polypeptide (alpha-hANP) in human plasma. Antibodies generated in rabbits recognized alpha-hANP-related peptides containing the subsequence flanked by two cysteine residues at position 7 and 23 equally. Radiolabelled tracer prepared by iodination with chloramine-T method was purified by high performance liquid chromatography. Immunoreactive (ir-) alpha-hANP was extracted from human plasma by Sep-Pak C18 column. The plasma ir-alpha-hANP concentrations in normal, healthy adults were 178 +/- 16 pg/ml in male and 182 +/- 18 pg/ml in female, respectively. Plasma ir-alpha-hANP increased significantly after acute intravenous administration of isotonic saline. Plasma levels were elevated in patients with various disease states accompanying increased body fluid volume, whereas those in patients with idiopathic edema were decreased despite excessive salt and water retention. These results suggest that alpha-hANP plays an important role in the regulation of body fluids and may have primary or secondary pathophysiological significance in various disease states.

Atrial natriuretic peptide correlates with pulmonary arterial pressure and cardiac output.

Correlations between plasma atrial natriuretic polypeptide (ANP) levels and hemodynamic parameters were studied in the central circulation of 12 patients with angina pectoris. The average plasma ANP level determined in the aorta was found to be 619 +/- 140 pg/ml. The plasma ANP levels showed a significant positive correlation with mean pulmonary arterial (PA) pressure, right ventricular pressure, and with cardiac index. In contrast, there was no significant correlation between plasma ANP levels and other hemodynamic variables including atrial pressure. These results suggest that hemodynamics other than the atrial pressure may have some role in modulating ANP secretion in certain pathological states.

Effects of recombinant human endostatin on a human neuroblastoma xenograft.

New antitumor agents must be added to the current neuroblastoma treatment regimens to improve the clinical results. We investigated whether recombinant human endostatin (rhEndostatin), an antiangiogenic agent, is effective against human neuroblastoma in the human neuroblastoma xenograft model designated TNB9. When tumors on the back of nude mice grew to a weight of 90-95 mg, rhEndostatin 10 mg/kg/day was administered subcutaneously every day for 10 consecutive days. Mean relative tumor weight in mice administered rhEndostatin (n=5) was significantly less than that in controls (n=12) on days 2, 4, and 6 after the start of administration (p<0.01 on day 2, p<0.05 on days 4 and 6), and regression of tumor growth (TRW<1.0) was marked on day 2. The maximum inhibition rate (MIR) by rhEndostatin was 46.4%, indicating inefficacy, but it may not be appropriate to apply Battelle Columbus Laboratories criteria to this experimental model because rhEndostatin is a protein. After day 8, tumors in the experimental group increased in weight and were not statistically significantly different from those in controls. Recombinant human endostatin was used in tumors in the arterial system of the mouse in this experiment because eventually rhEndostatin, not recombinant mouse endostatin, may be used to treat advanced neuroblastoma in the clinical setting. The results show that there is little cross-reactivity of rhEndostatin with the human and mouse models and indicate that rhEndostatin could become an effective agent for the treatment of human neuroblastoma.

Expression of multidrug resistance-related P-glycoprotein shows good prognosis in neuroblastoma.

Expression of P-glycoprotein was studied in formalin-fixed tissue sections from 75 materials with an immunoperoxidase (ABC) method using the monoclonal antibody MRK-16. Specimens examined were from three monkey fetuses, eight autopsy cases, and 64 neuroblastoma patients, 25 of whom were underwent mass screening for diagnosis. P-glycoprotein test results were positive in fetal lung alveolar tissue and in the adrenal medulla of three of seven adult autopsy cases. Expression of P-glycoprotein was demonstrated in 22 of 35 cases (63%) in a group of neuroblastoma patients younger than 12 months of age, as compared with 9 of 20 (31%) who were older than 12 months of age at diagnosis. P-glycoprotein positivity was higher in patients who were alive (25 of 40, 63%) than in those who had died (6 of 24, 25%). Previous studies on P-glycoprotein expression in neuroblastoma were carried out using specimens mainly from older children, and the results were not analyzed with reference to the findings in normal tissues. The present study has clearly shown that positive P-glycoprotein expression in neuroblastoma patients should be evaluated carefully in infant cases because it stains frequently in normal adrenal glands.

The role of subfractionation of alpha-fetoprotein in the treatment of pediatric surgical patients.

Subfractionation of serum alpha-fetoprotein (AFP) is a useful method to discriminate between yolk sac tumors, hepatic malignancies, and benign liver diseases in adults but has not been validated in infants and children. AFP subfractionation was performed on AFP-positive sera from 73 infants and children. AFP subfraction profiles were classified into three common types: (1) yolk sac type, (2) hepatoblastoma type, and (3) benign hepatic type, according to the reactivity of individual AFP samples to lectins. In 68 of 73 samples (93.2%), AFP subfraction profiles were accurately classified into these three types, and an atypical AFP subfraction profile resembling the hepatoblastoma type was found in sera from five infants (6.8%). Differentiation between hepatoblastoma and hepatitis when patients are very young can be difficult. Subfractionation is more accurate when patients are older. This technique was found to be useful in the diagnosis of neonatal ovarian tumors, in recurrent hepatoblastoma/ yolk sac tumor with low serum AFP, and in the differential diagnosis of hepatic mass (malignancy versus hyperplastic nodule) in the liver with long-standing cholestasis. Estimation of serum AFP subfraction profiles facilitates the differential diagnosis of various AFP-positive pediatric diseases, such as hepatoblastoma, hepatoma, hepatitis or germ cell tumors. This test is inexpensive, can be carried out within 48 hours, and should be performed for the differential diagnosis of pediatric liver disease.

A new technique applicable to pediatric laparoscopic surgery: abdominal wall 'area lifting' with subcutaneous wiring.

BACKGROUND: Recently, the authors developed a unique method of laparoscopic surgery without pneumoperitoneum: "area lifting of the abdominal wall with subcutaneous wiring." METHODS: In this gasless procedure, the anterior abdominal wall is pulled upward by a pair of wires placed subcutaneously and held by thick sutures for "hanger lifting." Simultaneous lifting of a pair of subcutaneous wires across the abdomen, produces a wide, roof-shaped intraabdominal space sufficient for laparoscopic surgical procedures. The practical aspects of this gasless technique, as well as the authors' limited experience with this method in 24 children, ranging from 8 days to 15 years of age is presented. These children have had various pathologies including splenomegaly, rectal prolapse, ovarian cyst, gall stone, adrenal neuroblastoma, and abdominal wall abscess. CONCLUSIONS: Gasless laparoscopic surgery with double subcutaneous wiring is safe for children including neonates and those with respiratory compromise because all operative procedures are performed under normal abdominal pressure. Because of the highly elastic abdominal wall musculature inherent in children, this selective area lifting of abdominal wall creates a relatively larger peritoneal volume than in adults.

Pancreatoblastoma treated by delayed operation after effective chemotherapy.

A case of pancreatoblastoma in a 4-year-old girl is presented. She was admitted with an abdominal mass and vomiting in August 1994. Computed tomography scan showed a 10- x 8- x 7-cm mass occupying both the head and body of the pancreas. Serum alpha-fetoprotein (AFP) level was 9,600 ng/mL (normal, <8.3 ng/mL). Results of open biopsy of the tumor showed pancreatoblastoma. Chemotherapy was administered using the new A-1 regimen consisting of cyclophosphamide, etoposide, pirarubicin, and cisplatin. After 3 cycles of chemotherapy, the size of the tumor was reduced to 5 x 4 x 3 cm, the portal vein became patent, and the AFP value decreased to 98.1 ng/mL. Total removal of the tumor was performed leaving the head and tail of the pancreas. Postoperative chemotherapy continued for 2 years. The patient has been disease free for 5 years, and her serum AFP remained within normal levels.

Development of a polyclonal antibody with defined specificity against synthetic peptides from the N-myc oncoprotein using multiple antigen peptide and hemocyanin conjugation methods.

BACKGROUND/PURPOSE: The importance of determining N-myc oncoprotein rather than genomic N-myc amplification has been emphasized in neuroblastoma, especially in an international project to register biological risk factors in all neuroblastomas. A method to raise a specific polyclonal antibody against the N-myc oncoprotein in large quantities was sought using the synthetic antigen peptide and the multiple antigen peptide (MAP) method. METHODS: Two sets of peptides, HGRGPPTAGSTAQSPG and GVAPPRPGGRQTSGGDH, conserved in the N-myc oncoprotein were synthesized. The hemocyanin-conjugated peptides and the lysine core-conjugated (multiple antigen peptide method) peptides were injected into rabbits with adjuvant. IgG fractions precipitated from the sera were purified on an affinity column coupled with these peptides, and the potency and specificity of the purified IgGs were examined by immunoblotting and immunohistochemistry in small cell lung cancer cell lines with known positivity-negativity of amplification and expression of N-myc, c-myc, and L-myc. RESULTS: Peptides conjugated to the lysine core raised more potent antibodies than those conjugated to hemocyanin. Purified IgG against GVAPPRPGGRQTSGGDH reacted positively with an N-myc-amplified lung cancer cell line, but not with N-myc-unamplified and c-myc/L-myc-amplified cell lines on either immunoblotting or immunostaining. This IgG strongly stained the nuclei of cells in a series of surgical specimens and cell lines of neuroblastoma with N-myc amplification. CONCLUSION: A polyclonal antibody specific for a synthetic peptide from the N-myc oncoprotein was thus obtained and will find wide international use.

Ileocecal resection in neonates and infants: a follow-up study.

From 1977 to 1983 ileocecal resection was done in five neonates and three infants who were admitted to our pediatric surgical units. Their growth, hematology, and serum biochemistry were examined and compared with that of an ileal resection group without ileocecal resection. The body weight and height of all patients of the ileocecal resection group were within normal ranges. All patients undergoing ileocecal resection in neonates had moderate diarrhea but condition of fecal evacuation improved after age 6. None of the control ileal resection group had diarrhea since age 2. No significant differences were noted in hematology and serum biochemistry (protein metabolism, lipid metabolism, bile acid, and vitamin B12) data between the ileocecal resection groups and the control group. Our findings show that after ileocecal resection without extensive ileal resection in neonates and infants, adequate nutritional status can be maintained.

Unusual pharyngeal lesion causing dysphagia.

A 58-year-old man was evaluated for a 42-year complaint of a pharyngeal foreign body sensation whenever he ate. Examination revealed normal anatomy at rest but diffuse hypopharyngeal distension with Valsalva's maneuver. His past history was remarkable for an infectious illness, possibly diphtheria. We speculate that this unusual case most likely represents a postdiphtheritic selective pharyngeal paralysis and present his case, radiographic findings, and a discussion of the differential diagnosis.

Competitive polymerase chain reaction for the determination of N-myc amplification in neuroblastoma: report of clinical cases.

If an unfavorable prognosis is suspected in neuroblastoma, decision on a treatment protocol should be based on the N-myc copy number (12). We already demonstrated that the newly developed competitive polymerase chain reaction (competitive PCR) is a promising method for the determination of the N-myc copy number (6), and have started to use this competitive PCR procedure in neuroblastoma patients, together with fine-needle biopsy in selected cases. Seven children were studied. In one infant of 5 months of age whose tumor was diagnosed before undergoing mass screening for neuroblastoma, the competitive PCR procedure was performed with a fine-needle biopsy, and after obtaining a negative report on N-myc amplification within 48 hours, a regular protocol of treatment could be started without delay. We report that competitive PCR is a rapid and accurate method for the determination of the N-myc copy number, requiring only a small amount of material, and anticipate that competitive PCR will become the procedure of choice for the determination of N-myc copy number in neuroblastoma.

Atrial natriuretic factor is biologically active also in the absence of vasopressin: studies on Brattleboro-strain diabetes insipidus rats.

Since atrial natriuretic factor (ANF) has been shown to inhibit vasopressin secretion, the role of this effect in the acute biological actions of ANF was investigated using Brattleboro-strain diabetes insipidus (DI) rats. Under thiobarbital anesthesia, synthetic rat ANF of a 25 amino acid sequence was administered intravenously as a bolus (8 micrograms/kg) into the jugular vein. The urine volume, urinary sodium and potassium concentration, blood pressure, and heart rate were determined. It was found that ANF administered exogenously can exhibit its diuretic, natriuretic and vasorelaxant activities even in the absence of vasopressin. This indicates that the inhibition of vasopressin secretion is not an indispensible mechanism for acute biological effects of ANF.

Antisera to atrial natriuretic factor reduces urinary sodium excretion and increases plasma renin activity in rats.

Although the presence of atrial natriuretic factor in the blood has been demonstrated by radioimmunoassay, its biological activity and physiological significance has not been elucidated. Using specific antiserum against atrial natriuretic factor, we investigated the effect of passive immunization in rats. A significant reduction of urine output and urinary sodium excretion lasted for about 30 min after intravenous administration of antiserum. The effects were more pronounced in rats pretreated with deoxycorticosterone acetate and saline. Plasma renin activity was increased after the administration of antiserum. No significant effects on the urinary sodium excretion was observed following injection of normal rabbit serum. The results of this study provide evidence indicating that endogenous atrial natriuretic factor plays an important role in the regulation of urinary water and sodium excretion and plasma renin activity.