In vivo degradation of calcium phosphate cement incorporated into biodegradable microspheres.

In this study we have investigated the influence of the mechanism of microsphere degradation or erosion on the in vivo degradation of microsphere/calcium phosphate cement composites (microsphere CPCs) used in tissue engineering. Microspheres composed of poly(lactic-co-glycolic acid) (PLGA), gelatin and poly(trimethylene carbonate) (PTMC) were used as the model and the resulting microsphere CPCs were implanted subcutaneously for 4, 8 or 12weeks in the back of New Zealand white rabbits. Besides degradation, the soft tissue response to these formulations was evaluated. After retrieval, specimens were analyzed by physicochemical characterization and histological analysis. The results showed that all microsphere CPCs exhibited microsphere degradation after 12weeks of subcutaneous implantation, which was accompanied by decreasing compression strength. The PLGA microspheres exhibited bulk erosion simultaneously throughout the whole composite, whereas the gelatin type B microspheres were degradated from the outside to the center of the composite. High molecular weight PTMC microspheres exhibited surface erosion resulting in decreasing microsphere size. Furthermore, all composites showed a similar tissue response, with decreasing capsule thickness over time and a persistent moderate inflammatory response at the implant interface. In conclusion, microsphere CPCs can be used to generate porous scaffolds in an in vivo environment after degradation of microspheres by various degradation/erosion mechanisms.

Observation of Y(2175) in J/psi --> etaphif0 (980).

The decays of J/psi --> etaphif(0)(980)[eta --> gammagamma, phi --> K(+) K(-), f(0)(980) --> pi(+)pi(-)] are analyzed using a sample of 5.8 x 10(7) J/psi events collected with the BESII detector at the Beijing Electron-Positron Collider. A structure at around 2.18 GeV/c(2) with about 5 sigma significance is observed in the phif(0)(980) invariant mass spectrum. A fit with a Breit-Wigner function gives the peak mass and width of m = 2.186+/-0.010(stat)+/-0.006(syst) GeV/c(2) and Gamma = 0.065+/-0.023(stat)+/-0.017(syst) GeV/c(2), respectively, which are consistent with those of Y(2175), observed by the BABAR Collaboration in the initial-state radiation process e(+)e(-) --> gamma(ISR) phif(0)(980). The production branching ratio is determined to be Br(J/psi --> etaY(2175))Br(Y(2175)- -> phif(0)(980))Br(f(0)(980) --> pi(+)pi(-)) = [3.23+/-0.75(stat)+/-0.73(syst)] x 10(-4), assuming that the Y(2175) is a 1(--) state.

[The effect of EDTA with different density on adhesive power of casting post and its scanning electromicroscopy (SEM) observation]

OBJECTIVE:To evaluate the effect of EDTA with different density on adhesive power of casting post.METHODS:Four different density of EDTA(5%,10%,15%,17%)were used to rinse the smear layer of root canal for 60 extracted teeth before they were cemented with ZP;on the other,a SEM observation was made on the rinse of root canal and the combination of adhesive and root canal.Meanwhile,a comparison was also made, after the rinse of EDTA,of tensile strength of casting post after their cement.RESULTS:EDTA with different density have different effect in the rinse of smear layer of root canal,it was proved by both SEM observation and the records of tensile strength of casting post. CONCLUSION:EDTA with density 10% is more effective in both the rinse of smear layer of root canal and the enhancement of adhesive power of casting post.

Origin of third-order optical nonlinearity in Au:SiO(2) composite films on femtosecond and picosecond time scales.

Three sorts of probe laser, which have pulse durations of 200 fs, 35 ps, and 70 ps, were employed in the measurement of the third-order nonlinear optical susceptibility x((3)) in Au:SiO(2) composite films in a degenerate four-wave mixing scheme. We found that the composite films at their absorption peak (~550 nm) had a maximum x((3)) , which depends strongly on the pulse width of the probe laser. The value of x((3)) measured with a 70-ps laser was ~30 times larger than that measured with a 200-fs laser. The time-resolved measurements revealed that the optical nonlinearity on the femtosecond time scale is attributable mainly to contributions from the interband electric-dipole transition (especially at low concentrations) and partly to those from hot electrons rather than being dominated by hot-electron excitation in the picosecond regime.

Effects of aluminum potassium sulfate on learning, memory, and cholinergic system in mice.

AIM: To study the relationship between aluminum potassium sulfate (APS) and memory deficits of mice. METHODS: 30, 60, or 90 d after the mice were given daily APS i.g., the step-through latency (STL) was determined with a passive avoidance task. Aluminum (Al) contents in brain and blood were assayed with atomic absorption spectrophotometry. Acetylcholine (ACh) content in brain was determined with chemiluminescent method and choline acetyltransferase (ChAT) activity was measured radiochemically. RESULTS: APS 1 g.kg-1 increased blood-Al only after 30 d. After 60 d, STL, ACh content and ChAT activity decreased by 46.4%, 8.5%, and 22.6%, respectively. These parameters decreased by 50%, 11.1%, and 27.8%, respectively, with increased Al in blood and brain, after 90 d. APS 0.25 g.kg-1 had no effects on mice except blood-Al. In ethylcholine mustard aziridium chloride (AF64A) treated mice, APS 1 g.kg-1 only increased blood and brain-Al. CONCLUSION: The intake of APS 1 g.kg-1.d-1 for 60 d induced learning and memory deficits in mice.

[Neonatal chylous ascites: report of two cases].

Chylous ascites in neonates is an unusual and etiologically poor understood entity. Our first case was a female newborn who suffered from abdominal distension and recurrent vomiting after birth. The history, physical, laboratory, and radiologic evaluations were not diagnostic except the evidence of obvious ascites. Paracentesis was performed and ascitic fluid was obtained. She was later discharged on a strict low-fat medium-chain triglycerides formula. She was found to have continue increase in abdominal girth, poor growth and development, and respiratory distress in which led her to readmission at 8 months of age. Exploratory laparotomy was done in order to rule out an anatomical lesion in which may be obstructing the lymphatic flow; but no such lesion could be found. She expired at 1 year of age with chylothorax, chylopericardium and lobar pneumonia. The second case, a 37-day-old male baby, who was admitted because of right inguinal hernia. Milky ascitic fluid in the abdomen was incidentally found during herniorrhaphy. Analysis of the fluid revealed protein 1,616 mg/dl, glucose 487 mg/dl, and triglyceride 796 mg/dl. Culture of peritoneal fluid grew no bacteria. Other laboratory findings were: serum protein 4.8 mg/dl, and BUN 14 mg/dl. A plain film of abdomen and sonogram showed massive ascites. The infant was then put on Pregestimil with the hope that the medium-chain triglyceride formula would improve his condition. Since then the child's abdominal girth did not increase and he continued to growth and develop normally at 4 months follow up.

[Clinical analysis and study of hypospadias].

We did a retrospective survey on 117 patients with hypospadias to determine what other congenital anomalies were present. We confirm the increasing incidence of chordee with severity of hypospadias. There were many other systemic anomalies associated with hypospadias. We found nongenitourinary tract malformations as follows: neuromuscular 1.7%, gastrointestinal 4.3%, cardiovascular 3.4%, ENT 0.8%, eye 0.8%. The incidence of genitourinary tract anomalies associated with hypospadias was 24.8% (undescended testis 11.1% and hernia 6.0%). Intravenous pyelography should be reserved for a selected group of children with hypospadias with abnormal ultrasonograms or urologic symptomatology. The primary therapeutic approach is surgical. Urethra-cutaneous fistula requiring additional surgery may occur following hypospadias repair in about 29.0% of cases in this paper.

Intracranial malignant rhabdoid tumor: report of one case.

A 4-year-old boy presented with anorexia, headache, and poor spirits was found to have tumors in posterior fossa and suprasellar region which enclosed by CT scan of brain. Bilateral suboccipital craniotomy was performed by neurosurgeon. The pathological report revealed the tumor was malignant rhabdoid tumor. The patient died two and one half months after diagnosis in spite of surgical resection and radiotherapy of the tumor.

[Multiple intestinal hemangioma: report of two cases].

Hemangioma of the small intestine is a rare disease which is sometimes very difficult to diagnose because of its anatomical location. This report concerns two cases of multiple intestinal hemangiomas treated surgically. The first case was a four-year-old boy who suffered from recurrent abdominal pain and progressive hemorrhage from the gastrointestinal tract for four months. The character of his abdominal pain was non-specific. On physical examination, whole abdominal tenderness was evident. Serial laboratory and radiological examinations, including abdominal sonogram, barium enema, Tc-99m pertechnetate scan, upper gastrointestinal series failed to reveal abnormality. Multiple intestinal hemangiomas were found at exploratory laparotomy. The second case was a new-born suffering from fetal ascites. Abdominal sonogram, barium enema, voiding cystourethrography were performed without significant findings, and the diagnose of multiple intestinal hemangiomas was proved by laparotomy. In both, symptoms improved after segmental resection of the bowels. The purpose of this paper is to draw attention to the possibility of intestinal hemangioma as a source of recurrent abdominal pain, tarry stool or ascites in children.

Antepartum diagnosis and management of idiopathic pericardial and pleural effusion: report of one case.

A case of an antenatal ultrasound diagnosis of pericardial effusion with pleural effusion is reported. Fetal pericardiocentesis, thoracentesis and amniocentesis were performed with real-time ultrasound guidance at 37 weeks of gestation. Laboratory investigations reported a rhesus-positive blood group, no atypical antibodies, negative serologic test for syphilis, and negative titers for toxoplasmosis. The laboratory data of the pericardial effusion showed: glucose 71 mg/dl, protein 3.7 gm/dl, LDH 73 U/L, CPK 53 U/L, negative culture for virus and bacteria. The pregnancy was terminated at 37 weeks of gestation by Cesarean section because of an edematously enlarged thorax. A 3540 gm male infant was delivered in a state of asphyxia with general cyanosis and an Apgar score of 3 and 4 at one and five minutes, respectively. His condition improved after endotracheal intubation and assisted ventilation. He was transported to the neonate intensive care unit, where chest roentgenogram confirmed pleural effusion over the left side. Chest tube was placed for 7 days. The infant was discharged on day 8, but the fluid reaccumulation over the left lung four months later. Chest tube was placed for five days. The infant subsequently has thrived with appropriated development for his age. We report herein because of successful technique of antepartal intervention.

[Child abuse: report of three cases].

Child abuse, a clinical condition in young children who have received serious physical abuse, is a frequent cause of permanent injury or death. The first case is a 7-year-old boy suffering from abdominal distension and pain for 3 days. He was beaten by his mother as a result of inadequately learning his lessons. Sonogram and CT of the abdomen showed massive ascites and a pseudocyst of the pancreatic body about 3 x 3 cm in diameter. The second case is a 4-year-old girl who developed a semicomatose state after her father impulsively struck her with a chair. CT of the brain revealed subdural hematoma over the left fronto-temporal region and midline shift to the right. She expired 5 days later. The third case, a 2-year-old girl, suffered from headache, seizure, vomiting and general malaise. CT of the brain showed severe brain swelling over the right side and midline shift to the left. She expired 1 month later. Psychiatric factors are probably of prime importance in the pathogenesis of the disorder, but our knowledge of these factors is limited. Parents who inflict abuse on children do not necessarily have psychopathic or sociopathic personalities or come from borderline socioeconomic groups, although most published cases fall into one of these categories. It is clearly the responsibility of all physicians serving children to be aware of, to recognize, and to properly manage any child who has been the victim of abuse.