High seroprevalence of Borna virus infection in schizophrenic patients, family members and mental health workers in Taiwan

Borna disease virus (BDV), a negative-strand RNA virus, has been reported to be associated with severe psychiatric disorders. The association is mainly based on the findings that patients with schizophrenia and depression have a higher seroprevalence rate of BDV-specific antibodies than controls. In addition, psychiatric patients were also found to have a higher detection rate of BDV transcripts in their blood than controls. By using an improved Western blot analysis, we first demonstrated that Chinese schizophrenic patients from Taiwan also have a higher seroprevalence of BDV-specific antibodies than controls (12.1% vs 2.9%, P< 0.001), providing support to the positive association between BDV and psychiatric disorders in our population. Because of the contagious nature of viral infection, we further examined patients' family members and mental health workers, who have close contact with patients. We found that both groups also have a higher seroprevalence of BDV-specific antibodies, 12.1% and 9.8%, respectively, than controls. This finding provides some evidence for a possible human-to-human transmission of Borna disease virus. Our finding needs further independent verification from other research groups and the clinical relevance of this preliminary observation deserves further study.

Heat shock protein expression during gametogenesis and embryogenesis

When cells are subjected to various stress factors, they increase the production of a group of proteins called heat shock proteins (hsp). Heat shock proteins are highly conserved proteins present in organisms ranging from bacteria to man. Heat shock proteins enable cells to survive adverse environmental conditions by preventing protein denaturation. Thus the physiological and pathological potential of hsps is enormous and has been studied widely over the past two decades. The presence or absence of hsps influences almost every aspect of reproduction. They are among the first proteins produced during mammalian embryo development. In this report, the production of hsps in gametogenesis and early embryo development is described. It has been suggested that prolonged and asymptomatic infections trigger immunity to microbial hsp epitopes that are also expressed in man. This may be relevant for human reproduction, since many couples with fertility problems have had a previous genital tract infection. Antibodies to bacterial and human hsps are present at high titers in sera of many patients undergoing in vitro fertilization. In a mouse embryo culture model, these antibodies impaired the mouse embryo development at unique developmental stages. The gross morphology of these embryos resembled cells undergoing apoptosis. The TUNEL (terminal deoxynucleotidyl transferase-mediated X-dUTP nick end labeling) staining pattern, which is a common marker of apoptosis, revealed that embryos cultured in the presence of hsp antibodies stained TUNEL-positive more often than unexposed embryos. These data extend preexisting findings showing the detrimental effect of immune sensitization to hsps on embryo development.

Surgery for achalasia: long-term results in operated achalasic patients

Achalasia is a functional disorder of the alimentary tract due to decreased or absent peristalsis of the esophageal body and obstructive outlet of the esophagus. Surgical treatment, eg. esophagomyotomy of the lower esophageal sphincter (LES), was one choice for resolving the problem and its effect was affirmative from reviews of many internationally authorized articles. However, few reports have ever questioned the long-term effects of it. From January 1968 to May 1996, 159 esophageal achalasic patients, 90 males and 69 females, were admitted due to dysphagia or food regurgitation. One hundred and forty-five patients had received 158 operations related to this benign motor disorder. The majority of patients received either modified Heller esophagomyotomy (M) or M plus modified Belsy Mark IV antireflux procedure (M+W) for primary treatment of their esophageal disorder, while conditional selection with addition of esophageal resection as advanced procedures for failure of primary surgery. We retrospectively studied these patients, collected their preoperative and postoperative clinical results, analyzed the causes of recurrent symptoms, compared the long-term results in different surgical procedures and searched for the pathogenesis of their failure. The results disclosed that the overall success rate for both methods was 73.1% with 85.7% for patients receiving M+W (56) and 64.9% of M (77) only. Through long-term follow-up, we had an improvement rate of 97.4% at an early stage and 53.3% for M at a late stage and 98.4% and 55.6% for M+W, respectively. The postoperative natural course of achalasic patients could be seen and progressive deterioration of the operated patients with time was noted. Several factors might contribute to the causes of unsuccessful surgery. We summarized them as incomplete myotomy, fused or healed myotomy, gastroesophageal reflux (GER), mucosal hernia and co-combined antireflux procedure by hypercalibrated or floppy wrapping. Esophagomyotomy or myotomy plus antireflux procedure for the esophagus could be concluded to rather effective in the long-term but palliative treatments for achalasia chronic deterioration of the results could be found for both of them. Defective myotomy and GER may be the major causes for their failure. The choice of types of surgery between M and M+W was not the cause of the unsuccessful results whereas the operative strategy and procedures would have a certain significance on the long-term effect.

Anaesthesia for transmyocardial laser revascularization--initial experience with seven patients

The introduction of transmyocardial laser revascularization for ischaemic heart disease has brought with it new challenges for anaesthetists. These include acute deterioration of cardiac function, the need for emergency cardiopulmonary bypass and difficulty weaning from haemodynamic support. Recurrent arrhythmias can occur despite amiodarone prophylaxis. We describe our initial experience and the problems we encountered.

Human preembryo development on autologous endometrial coculture versus conventional medium

OBJECTIVE

To evaluate the effect of autologous endometrial coculture versus conventional medium on preembryo development.

DESIGN

Controlled systematic clinical study.

SETTING

University-based IVF center.

PATIENT(S)

Women with a history of failed IVF-ET with poor preembryo quality.

INTERVENTION(S)

Patients underwent a luteal phase endometrial biopsy. The tissue then was digested enzymatically, and the stromal and glandular cells were separated by differential sedimentation rates. These cells were cultured to confluence, released, and then cryopreserved until the patient's IVF-ET cycle. All normally fertilized oocytes then were allocated systematically to growth on autologous endometrial coculture or conventional medium until transfer on day 3.

MAIN OUTCOME MEASURE(S)

Preembryo blastomere numbers and cytoplasmic fragmentation rates were measured.

RESULT(S)

Forty-two women underwent 44 cycles of IVF-ET. In the morning on day 3, the mean (+/-SD) number of blastomeres and cytoplasmic fragments per preembryo on coculture compared with conventional medium was 5.9+/-1.5 versus 5.5+/-1.4 and 21%+/-13% versus 24%+/-11. At transfer the mean (+/-SD) number of blastomeres per preembryo on coculture was 7.4+/-1.3 versus 6.7+/-1.9 on conventional medium.

CONCLUSION(S)

There was a significant improvement in the mean (+/-SD) number of blastomeres per preembryo and decrease in the fragmentation rate for preembryos on autologous endometrial coculture compared with noncocultured preembryos from the same patient.

Granulocyte macrophage-colony stimulating factor production by autologous endometrial co-culture is associated with outcome for in vitro fertilization patients with a history of multiple implantation failures

PROBLEM

To determine whether granulocyte macrophage (GM)-colony stimulating factor (CSF) produced by autologous endometrial co-culture was associated with outcome in 53 patients with a history of multiple in vitro fertilization failures.

METHOD OF STUDY

The conditioned media from endometrial co-culture cells exposed or non-exposed to human embryos was analyzed for GM-CSF.

RESULTS

Exposure or non-exposure to an embryo did not result in an enhancement of GM-CSF production. Insignificant levels of GM-CSF were determined from media alone. ROC analysis revealed that levels of GM-CSF from supernatants of endometrial co-culture exposed to embryos that measured below 130 pg/ml reflected a diminished prognosis (5/17 had a positive pregnancy vs. 21/36 with GM-CSF levels greater than 130 pg/ml; P < 0.05).

CONCLUSIONS

The improved outcome associated with GM-CSF values greater than 130 pg/ml may reflect: 1) a direct positive effect of GM-CSF; 2) an embryotrophic factor upregulated by GM-CSF; or, 3) that GM-CSF functions as a marker for the importance of the glandular component in endometrial co-culture systems.

Transcriptional regulation of mouse mu-opioid receptor gene

Previously, the existence of dual promoters was reported in mouse mu-opioid receptor (mor) gene, with mor transcription in the mouse brain predominantly initiated by the proximal promoter. In this study, we further analyzed the proximal promoter region, base pairs -450 to -249, to identify cis-DNA regulatory elements and trans-acting protein factors that are important for mor promoter activity. The results revealed that a mor inverted GA (iGA) motif and a canonical Sp1 binding site are required for the promoter activity. Using electrophoretic mobility shift analysis, we identified nuclear proteins that specifically bind to the mor iGA motif and that are immunologically related to Sp1 and Sp3. Mutation of the mor iGA motif, resulting in a loss of Sp binding, led to a 50% decrease in activity. Mutation of the canonical Sp1 binding site yielded a lesser (approximately 25%) loss of activity. Mutation of both motifs together resulted in an approximately 70% decrease in activity. In cotransfection assays using Drosophila SL2 cells, Sp1 trans-activated the promoter in a manner dependent on the presence of mor iGA and canonical Sp1 binding motifs. Sp3 can also trans-activate the promoter, and furthermore, Sp1 and Sp3 can trans-activate the mor promoter additively. Our results suggest that combined or cooperative interaction of Sp transcription factors within the proximal promoter is necessary for activation of mor gene transcription.

Enantiomeric inhibitors of cholesterol esterase and acetylcholinesterase

Enantiomers of N-methyl-N,alpha-methylbenzylbutyramide (1), 1-butyl-3-methyl-3'-alpha-methylbenzylurea (2), 1,2,3, 4-tetrahydro-1-naphthyl-N-butylcarbamate (3), 1,1'-bi-2-naphthyl-2, 2'-di-N-butylcarbamate (4), 1, 1'-bi-2-naphthyl-2-ol-2'-N-butylcarbamate (5), and 1, 1'-bi-2-naphthyl-2-butyrate-2'-N-butylcarbamate (6) are inhibitors of porcine pancreatic cholesterol esterase-catalyzed hydrolysis of 4-nitrophenyl butyrate and of electric eel acetylcholinesterase-catalyzed hydrolysis of acetylthiocholine in the presence of 5,5'-dithiobis-2-nitrobenzoate. For competitive inhibitors, values of the inhibition constant (Ki) and the enantiomeric ratio (Ecomp.) are investigated. For active site-directed irreversible inhibitors, values of the inhibition constant (Ki), the carbamylation constant (k2), the bimolecular rate constant (ki), and the enantiomeric ratio (E) are investigated. Toward both enzymes, compounds 1 are poor competitive inhibitors (Ki=102-104 microM) but have good enantioselectivities (Ecomp.=10-50, the preference for R). R-2 and S-2 are competitive inhibitors of acetylcholinesterase with Ki=26 and 80 microM, respectively (the preference for R) but are active site-directed irreversible inhibitors of cholesterol esterase with ki=4 and 16 M-1 sec-1, respectively (the preference for S). For those competitive inhibitions, both leaving group hydrophilic and hydrophobic binding sites of cholesterol esterase or both anionic substrate binding site and peripheral anionic binding site of acetylcholinesterase bind to N,N-methyl-alpha-methylbenzyl disubstituted amide parts of these inhibitors and the enzyme does not catalyze the hydrolysis of these inhibitors. The opposite stereopreference (S) for the inhibition of cholesterol esterase by compounds 2 may be due to the fact that N, N-methyl-alpha-methylbenzyl disubstituted amide parts of these inhibitors bind to the alkyl chain binding site of the enzyme. Compounds 3-6 are active site-directed irreversible inhibitors of cholesterol esterase (ki=1-13000 M-1 s-1) and peripheral anionic binding site-directed irreversible inhibitors of acetylcholinesterase (ki=1.7-1300 M-1 s-1). Compounds 3 have low enantioselectivities (E=1.3-1.4) for both enzymes. The stereopreference for atropisomers 4 and 6 is S-form toward both enzymes (E=2-30) and is identical to that of cholesterol esterase-catalyzed hydrolysis of 1,1'-bi-2-naphthyl-2,2'-diacylate. This stereopreference (S) may be due to the fact that the butyryl group or one of two butylcarbamate groups of S-atropisomers binds more effectively to the leaving group hydrophobic binding site of cholesterol esterase or the peripheral anionic binding site of acetylcholinesterase than that of R-atropisomers. The opposite stereopreference (R) for atropisomers 5 toward both enzymes may be due to a favorable interaction between the hydroxyl group of the inhibitors and the leaving group hydrophilic binding site of cholesterol esterase or the peripheral anionic binding site of acetylcholinesterase.

A directed search for quantitative trait loci on chromosomes 4 and 7 in pigs

Improvements in the porcine genetic map and availability of resource families to study performance traits in pigs have made it possible to re-examine previous findings that linked certain traits to genes or chromosomal regions. Previous studies suggested that chromosomes 4 and 7 may be associated with growth and performance traits. To confirm these previous results, an interval mapping-regression approach was used to determine whether quantitative trait loci (QTL) exist in the Iowa State University reference/resource families. Traits measured were birth weight; body weight at 21 d; weaning weight (weight at 42 d); average daily gain; backfat at the first, 10th, lumbar, and last ribs and average backfat thickness; loin eye area; meat color; marbling; and firmness. The total number of F2 pigs used ranged from 241 to 330 and came from five Chinese x American resource families. Five markers (S0001, SW871, S0175, S0214, and SW445) were genotyped and mapped on chromosome 4, and so were 10 markers (S0064, tumor necrosis factor alpha [TNFalpha], S0102, S0078, S0158, S0066, SW304, SW1083, S0101, and S0212) on chromosome 7. Data were analyzed for each family (breed cross) separately and were also pooled. Experiment-wise thresholds were used to determine significance. Suggestive evidence of QTL on chromosomes 4 and 7 was observed for several traits in pooled and individual family analyses. Suggestive evidence of a QTL with a relatively large effect for average daily gain was detected on chromosome 4 in the pooled analysis. Significant (P < .05) evidence for QTL was seen on chromosome 7 for 10th-rib, last-rib, and average backfat thickness in the pooled data set in a region of the chromosome that was near TNFalpha. These results verify in part that chromosomes 4 and 7 contain QTL for growth and carcass traits.

Prevalence and subtypes of dementia in a rural Chinese population

We conducted a single-stage community-based study of dementia on all registered residents > or =65 years in age in a rural Chinese community. Neurologists conducted semistructured interviews and examined all participants; they also interviewed family members in cases where dementia was suspected. The diagnosis was made by consensus according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders, 3rd ed, revised (DSM-III-R). Among the 2,055 contacted individuals, 1,736 (84.5%) participated in the study and 44 ( 13 men and 31 women) were diagnosed as having dementia, including 35 (80%) with probable Alzheimer disease (AD) and 3 (7%) with vascular dementia (VsD). The rates of dementia were 0.5% for ages 65-74 years, 2.9% for ages 75-84 years, and 12.0% for ages 85-101 years. The overall rate was 2.5% for age > or =65 years. After controlling for age, neither a lack of formal education nor being a woman was a risk factor for dementia. At 2-year follow-up, 30 of the 44 demented participants had died, yielding a 2-year survival rate of 32%. The present results corroborated our previous findings of lower prevalence rates of dementia among the Chinese than among Western populations, and both genetic and sociocultural factors may have contributed to the low rates. The lack of neuroradiological imaging studies in the present study may have contributed to the finding of an unusually low rate of VsD.

Stress distribution in the mandible with unilateral condylar fracture

OBJECTIVE

The purpose of this study was to investigate the influence of unilateral condylar neck fracture upon the stress distribution in the mandible and the temporomandibular joint (TMJ) to realize primarily the biomechanical mechanism of the temporomandibular joint disorders (TMD) caused by TMJ injury.

METHODS

The character of stress distribution in the mandible of a normal human and a patient with TMD induced by unilateral condylar neck fracture followed by malpositioned healing was analyzed quantitatively and compared during centric occlusion by combining spiral computed tomography scanning technology with the three-dimensional finite element method.

RESULTS

The patient with unilateral condylar neck fracture followed by malpositioned healing had unbalanced stress distribution in the mandible, such as differing nature and value of stress. The stress in the fractured side was higher than in the nonfractured side, in which the condyle was more evident. The maximum principal stress and minimum principal stress of each region in the fractured mandible were much higher than those in a normal mandible. Stress quality also differed.

CONCLUSIONS

The abnormal stress changes after unilateral condylar neck fracture with malpositioned healing may be related to the effect of condylar shape change on masticatory muscle function and occlusion. TMJ injury not only damaged the condylar structure, but also compromised its biomechanic environment. It is preliminarily thought that unbalanced stress distribution, evidently increased stress, and varied stress character are biomechanic mechanisms of TMD. Condylar dislocated fracture should be treated promptly and properly to maintain the proper prognostic stress distribution.

Immunohistochemical analysis of insulin-like growth factor-binding proteins -1, -2, and -3 in implantation sites of the mouse

PURPOSE

Our purpose was to analyze potential interactions between the embryo and the maternal endometrial interface in vivo by analyzing immunolocalization of insulin-like growth factor-binding proteins (IGFBPs) -1, -2, and -3 in implantation sites of the mouse.

METHODS

Six-week-old B6D2F1 female mice underwent superovulation followed by mating and sacrifice at timed intervals. Formalin-fixed paraffin-embedded tissue was used for avidin-biotin immunocytochemical localization of IGFBPs utilizing standard methodology.

RESULTS

Immunostaining at 1.5 days post coitum revealed light staining in the epithelial glandular cells and faint staining in decidual stroma for both IGFBP-1 and IGFBP-2. At 7.5-10.5 days post coitum, there was moderate-dense immunostaining in the decidualized stromal cells at the implantation site for all three IGFBPs, whereas light immunostaining was seen in nonimplantation site decidua.

CONCLUSIONS

Compartmentalization of immunostaining for IGFBP-1, -2, and -3 within decidualized stroma suggests that these proteins may be regulated by trophoblastic and/or embryonic signals.

Evolution of the avian sex chromosomes from an ancestral pair of autosomes

Among the mechanisms whereby sex is determined in animals, chromosomal sex determination is found in a wide variety of distant taxa. The widespread but not ubiquitous occurrence, not even within lineages, of chromosomal sex determination suggests that sex chromosomes have evolved independently several times during animal radiation, but firm evidence for this is lacking. The most favored model for this process is gradual differentiation of ancestral pairs of autosomes. As known for mammals, sex chromosomes may have a very ancient origin, and it has even been speculated that the sex chromosomes of mammals and birds would share a common chromosomal ancestry. In this study we showed that the two genes, ATP5A1 and CHD1, so far assigned to the female-specific W chromosome of birds both exist in a very closely related copy on the Z chromosome but are not pseudoautosomal. This indicates a common ancestry of the two sex chromosomes, consistent with the evolution from a pair of autosomes. Comparative mapping demonstrates, however, that ATP5A1 and CHD1 are not sex-linked among eutherian mammals; this is also not the case for the majority of other genes so far assigned to the avian Z chromosome. Our results suggest that the evolution of sex chromosomes has occurred independently in mammals and birds.

Effects of thrombopoietin on megakaryocyte colony formation from leukemic cells at diagnosis and from marrow cells after induction chemotherapy for acute leukemias

We have studied the effects of recombinant human thrombopoietin (TPO, mpl ligand) on the megakaryocyte colony formation from control human bone marrow cells, human leukemia cells at diagnosis, and human bone marrow cells after induction chemotherapy for acute leukemias. In the control human bone marrow cells from four adults and nine children who had localized malignancy and histologically normal-looking marrow. TPO alone effectively stimulated megakaryocyte colony formation, and interleukin-3 (IL-3) synergized this. In 17 patients (13 adults and four children) with acute myeloid leukemia (AML) at diagnosis, TPO stimulated leukemic colony formation in only one patient with FAB M7 subtype. In 11 children with acute lymphoblastic leukemia (ALL) at diagnosis, TPO did not enhance leukemic colony formation. After 17 courses of induction chemotherapy, nine for AML and eight for ALL, TPO stimulated megakaryocyte colony formation to a level of 51%, of that in the control human bone marrow cells. This may suggest that the administration of TPO to patients with M7 subtype warrants caution, whereas it is probably safe to give TPO at any time to patients with ALL. The administration of TPO to patients with acute leukemias after induction chemotherapy could stimulate megakaryocytopoiesis.

Assessment of protein conformation in human benign and malignant astrocytomas by reflectance Fourier transform infrared microspectroscopy

The secondary structure and composition of protein in the tissues of benign and malignant astrocytomas were determined by reflectance Fourier-transform infrared (FT-IR) microspectroscopy. The peak maximum of IR spectra of the tissues from recurrent malignant astrocytoma markedly appeared at higher frequency (1655 or 1663 cm(-1)), which was significantly different from that of the tissues from benign astrocytoma at 1651 cm(-1) and tissues from malignant astrocytoma at 1652 cm(-1). Malignant astrocytoma indicated slightly different compositions in the protein secondary structure from benign astrocytoma. However, a significant increase in beta-turn structure but a marked decrease in beta-sheet and random coil structures were observed in the protein secondary structure of the recurrent malignant astrocytoma. The phenomenon was more pronounced in recurrent malignant astrocytoma pretreated with radiation and chemotherapy. The rapid cell proliferation and cell differentiation of malignant astrocytoma with or without recurrence might be the possible explanations for the different compositions of protein conformational structures.

Association of apolipoprotein E genotype and intronic polymorphism of the presenilin-1 gene with Alzheimer's disease in elderly Taiwan Chinese

We studied the apoliprotein E (apo-E) allele frequencies and intronic polymorphism of the presenilin-1 (PS-1) gene in 55 patients with late-onset Alzheimer's disease (AD) and 93 age- and sex-matched controls. The apoE epsilon4 allele frequency was significantly higher in the AD group than in the control group (0.255 versus 0.070, P<0.0001). The odds ratio for AD in individuals with either one or two epsilon4 alleles was 5.22 (95% confidence interval: 2.32-11.70). The polymorphism within the region composing intron 3' to exon 8 of the PS-1 gene showed a similar distribution between AD patients and controls. This is the first study on the intronic polymorphism of the PS-1 gene in Chinese. Our results support an association between apoE epislon4 and AD in Chinese, but not between the intronic polymorphism of the PS-1 gene and AD. However, the allele frequency of apo-E epsilon4 among Chinese is lower than that among Caucasians. The interaction between apo-E and PS-1 genotypes is still unclear.

mu-Opioid receptor-knockout mice: the role of mu-opioid receptor in gastrointestinal transit

The role of mu-opioid receptor in gastrointestinal transit was investigated using mu-opioid receptor knockout mice (MOR-KO). Our result establishes unequivocally that inhibition of GI transit by morphine is a mu-opioid receptor mediated function. In addition, we show that neither delta nor kappa receptor agonist given supraspinally or peripherally are able to inhibit GI transit in MOR-KO animals. It was interesting to observe that basal GI motility was lower in MOR-KO (-/-) compared to heterozygous (+/-) and wild type (+/+) animals.

High-dose cytarabine-containing chemotherapy with or without granulocyte colony-stimulating factor for children with acute leukemia

We sought to determine the role of granulocyte colony-stimulating factor (G-CSF) as an adjunct therapy in high-dose cytarabine-containing chemotherapy (HD C/T) for children with acute leukemia. Seventeen patients, aged 9 months to 18 years old, 8 ALL and 9 AML, were treated with cytarabine (Ara-C) 1 g/m2 q12h for 8 doses with mitoxantrone, idarubicin, VP-16, or asparaginase. A total of 71 courses of HD C/T was given. G-CSF was not used in 14 courses (Group A). Prophylactic G-CSF was given in 57 courses (Group B) as 200 microg/m2/d SC started one day after the completion of HD C/T and continued until the neutrophil recovery was maintained. The incidences of sepsis per course in Group A and Group B were 35.7% (5/14) and 40.4% (23/57), respectively. While 2 patients in Group A died of sepsis or pneumonia, none in Group B died. The mortality and delay in chemotherapy were fewer in Group B (P = 0.037 and 0.0006, respectively, Fisher exact test). There was a shorter average number of days of neutrophil <500/cumm, antibiotic usage, fever, and hospital stay in Group B (11, 8, 5, 17 days in Group B vs. 21, 17, 10, 37 days in Group A; P = 0.0001, log-rank test; 0.0006, 0.0023, 0.0001, Wilcoxon rank sum test, respectively). The incidence of neutropenic fever was lower in Group B, but the difference did not reach statistical significance (P = 0.06, Fisher exact test). We conclude that G-CSF as an adjunct therapy in HD C/T is effective in reducing mortality, days of neutropenia, antibiotic usage, fever, hospital stay, and frequency of delay in chemotherapy. The efficacy of this treatment approach requires further testing in a randomized, controlled trial.

Biological effects and cytotoxicity of the composite composed by tricalcium phosphate and glutaraldehyde cross-linked gelatin

The purpose of this study was to prepare and evaluate the feasibility and cytocompatibility of a composite (GTG) as a large defect bone substitute. The composite is combined with tricalcium phosphate ceramic particles and glutaraldehyde cross-linked gelatin. Gelatin had been reported as an adhesive and biocompatible binder that could accelerate the recovery of damaged soft tissue, but the effects of gelatin when acting on the bone tissue is not clear. Thus, it is necessary to determine if the substances released from the GTG composite can facilitate the growth of bone cells. The substances released from the GTG composites after being soaked in deionized distilled water were analyzed by gas chromatography (GC), ultraviolet and visible absorption spectroscopy (UV-VIS), and inductive-coupled plasma-atomic emission spectrometry (ICP-AES). The cytotoxicity of the GTG composites was assessed by coculture of rat osteoblasts in vitro. Extracts were obtained by soaking the GTG composites in deionized distilled water for 1, 2, 4, 7, 14, 28 and 42 d. The extract mixed with complete medium in a ratio of 1:1 was added into the cell culture wells containing 1 x 10(4) cells ml(-1) osteoblasts. After culturing for 2 days, the cells attached to the surface of wells were trypsinized and the number calculated by the Neubauer counting-chamber under the optical microscope. Finally, three samples in each GTG group were examined by scanning electron microscopy (SEM) to observe the morphology of the osteoblasts attached to the surfaces of GTG composites. The examinations of osteoblasts cocultured with the developed GTG composites were used to decide the ideal concentration of glutaraldehyde as a cross-linking agent. The results of extracts cocultured with osteoblasts showed that the extracts obtained from the 2, 4 and 8% glutaraldehyde cross-linked GTG composites would inhibit the growth of osteoblasts in the first 4 soaking days. During the 4-7 days soaking, the cell numbers quickly increased with the soaking time, thereafter, the cell numbers almost reached a constant value. In the analyses of substances released from the GTG composites, it was found that the gelatin and calcium were gradually released from the GTG composites, which were supposed to be nutritious for the growth of the osteoblast. The results of osteoblasts cocultured with the GTG composites showed that the concentration of glutaraldehyde used as a cross-linking agent should be lower than 8%. Compared to the GTF (composite combined with tricalcium phosphate ceramic particles and formaldehyde cross-linked gelatin), GTG composites were much suitable for a large defect bone substitute in the near future.

The stage I yolk sac tumor of testis in children younger than 2 years, chemotherapy or not?

Yolk sac tumor is the most frequent germ cell tumor of testis in children. For stage I yolk sac tumor of testis in children younger than 2 years, high inguinal orchiectomy alone has been the standard treatment, with a cure rate of at least 75%. Here, we compare the treatment results of receiving chemotherapy or no chemotherapy after orchiectomy, to analyze the role of chemotherapy. From February 1987 to January 1997, 22 children younger than 2 years, with stage I yolk sac tumor of testis, were included in the study. All patients had high inguinal orchiectomy without retroperitoneal lymphadenectomy. Initial diagnostic imaging studies included computed tomographic scan of abdomen, chest radiography, and long bone survey. Clinical stage I was defined as a tumor completely resected with no evidence of local regional lymph node involvement or distant metastases. Serum alpha-fetoprotein (AFP) was assessed at diagnosis. After orchiectomy, diagnosis, and staging, patients were stratified into two treatment groups, with or without chemotherapy, according to the decision of the parents. Ten children received chemotherapy consisting of cisplatin, vinblastine, and bleomycin (PVB, modified "Einhorn regimen") for 12 weeks. The remaining 12 patients were followed up according to a "wait and see" policy. Determination of AFP was performed monthly during the first postoperative year, every other month during the second year, every 3 months during the third year, every 6 months during the fourth year, and yearly until the fifth postoperative year at least. The duration of follow-up ranged from 3 months to 119 months (median, 53 months). The Kaplan-Meier plot estimated an overall survival rate of 91.6% at 7 years after diagnosis. Among the 12 patients without chemotherapy, 2 children had relapses at 4 and 6 months after diagnosis, respectively. One was cured with PVB chemotherapy. The other patient died with refractory lung metastasis, in spite of intensive multimodality salvage therapy. The Kaplan-Meier plot showed a survival rate of 80% at 7 years and a relapse-free survival rate of 81.8% at 5 years after diagnosis. All children receiving chemotherapy were alive and free from relapse. There was no significant treatment-related toxicity. Our results may suggest that PVB chemotherapy after orchiectomy is an affective and safe regimen for stage I yolk sac tumor of testis in children younger than 2 years. Instead of four courses of PVB as used here, two or three courses could be enough. To elucidate the necessity for chemotherapy and to determine the number of courses of PVB needed (if chemotherapy is given), a randomized study of more cases is warranted.

Ovarian estradiol production in vivo. Inhibitory effect of leuprolide acetate

OBJECTIVE

To determine the impact of reducing the dose of gonadotropin-releasing hormone agonist (GnRH-a) for controlled ovarian stimulation in in vitro fertilization (IVF) on subsequent response to stimulation and cycle outcome.

STUDY DESIGN

An IVF database was searched to identify patients who underwent at least two cycles of ovarian stimulation at a university-based medical center, and a retrospective chart review was performed. Fifty-one patients whose IVF stimulation protocols during the two cycles were identical except for the leuprolide dosage utilized for luteal pituitary suppression were included in the study. Two leuprolide dosages were utilized for suppression: a low dose, 0.5 mg daily, and a high dose, 1 mg daily. The leuprolide dose was uniformly halved upon initiation of gonadotropin stimulation; the gonadotropin dose and preparation were identical in the two protocols. Day 3 follicle-stimulating hormone levels, duration of stimulation, amount of gonadotropins required, midcycle and peak estradiol levels, oocyte yield and implantation rates were compared.

RESULTS

Lowering the dose of GnRH-a while maintaining the same stimulation protocol resulted in a faster estradiol rise and higher mean peak estradiol level. The higher estradiol levels were obtained with a lower total gonadotropin dose. The oocyte yield was not affected by the stimulation protocol utilized.

CONCLUSION

Lowering the dosage of leuprolide allows higher estradiol levels in those patients. This suggests an inhibitory in vivo effect of leuprolide acetate on ovarian steroidogenesis.

Characteristics of consecutive in vitro fertilization cycles among patients treated with follicle-stimulating hormone (FSH) and human menopausal gonadotropin versus FSH alone

OBJECTIVE

To compare the endocrine responses of patients who first received hMG plus FSH, then were treated in a subsequent cycle with FSH alone.

DESIGN

Retrospective study.

SETTING

An academic research environment.

PATIENT(S)

Ninety-six women with pituitary down-regulation who underwent two sequential IVF treatments, the first with combined hMG and FSH and the second with FSH alone.

MAIN OUTCOME MEASURE(S)

Duration of stimulation, serum estradiol level on the day of hCG administration, amount of gonadotropin used, number of oocytes retrieved, number of oocytes fertilized, and selected preembryo morphologic features.

RESULT(S)

No difference in the mean duration of stimulation was observed between the treatment cycles among patients who received hMG and FSH (11.9 days) followed by FSH alone (11.7 days). The mean number of oocytes retrieved, the mean number of oocytes fertilized, the percentage of preembryo fragmentation, and the preembryo cell number at transfer did not differ significantly between the stimulation protocols. The cumulative amount of gonadotropin used during stimulation was slightly greater in the cycles stimulated with FSH alone, but this difference was not significant (29.4 ampules of hMG plus FSH versus 31.8 ampules of FSH alone). Serum estradiol levels measured on the day of hCG administration during stimulation with hMG and FSH (1,382 pg/mL) were higher than those measured during stimulation with FSH alone (1,149 pg/mL).

CONCLUSION(S)

Follicular response and preembryo quality were not significantly different when patients were treated first with hMG and FSH and then with FSH alone in a subsequent cycle. Similarities in ovarian response and preembryo characteristics, as well as differences in estradiol patterns seen in each stimulation setting, should be anticipated when patients receive these protocols.

Monoclonal antibodies to mammalian heat shock proteins impair mouse embryo development in vitro

Two-cell mouse embryos (B6D2F1) were cultured in the presence or absence of 100 microg/ml monoclonal antibodies specific for the mammalian 60 kDa (HSP60), 70 kDa (HSP70) and 90 kDa (HSP90) heat shock proteins. Embryo development was evaluated after 3, 5 and 7 days in culture by determining the number of blastocysts, hatched blastocysts and outgrown trophoblasts at the successive time points. At day 3, only 29% (22/75) of the embryos cultured with anti-HSP60 antibody developed to the blastocyst stage (P < 0.0001) as compared to 67% (31/46) of the embryos cultured with anti-HSP70, 72% (43/60) cultured with anti-HSP90, and 79% (49/62) in medium plus mouse IgG1. By day 5, hatched embryos were present in 28% (13/ 46) of the cultures containing anti-HSP70 (P < 0.0001), as opposed to 57% (34/60) containing anti-HSP90 and 73% (45/62) containing IgG1. At day 7, outgrown trophoblasts were observed in 9% (4/46) of cultures containing anti-HSP70 (P < 0.0001), 45% (27/60) containing anti-HSP90 (P < 0.01) and 66% (41/62) cultured in medium plus IgG1. Antibodies to different heat shock proteins exerted a detrimental effect on mouse embryo development at unique development stages. Immune sensitization to heat shock proteins may be a cause of reproductive failure.

Influence of hydroxyapatite particle size on bone cell activities: an in vitro study

Over the past decade, a large number of biomaterials have been proposed as artificial bone fillers for repairing bone defects. The material most widely used in clinical medicine is hydroxyapatite. The aim of our investigation was to study the effect of hydroxyapatite size mechanism on osteoblasts. The osteoblasts were cultured in vitro with 0.1% (1 mg/mL) of various sized hydroxyapatite particles (0.5-3.0, 37-63, 177-250, and 420-841 microm) for 1 h, 3 h, 1 day, 3 days, and 7 days. The results showed that adding hydroxyapatite particles to osteoblast cultures can significantly affect osteoblast cell count. Osteoblast populations decreased significantly. Osteoblast mean surface areas also changed significantly. Transforming growth factor-beta1 (TGF-beta1) concentrations in culture medium decreased significantly with the addition of hydroxyapatite particles. Prostaglandin E2 (PGE2) concentrations in medium increased significantly. The changes in TGF-beta1 and PGE2 concentration were more significant and persisted longer in smaller-particle groups. The inhibitory effects of hydroxyapatite particles on osteoblast cell cultures were mediated by the increased synthesis of PGE2. Caution should be exercised before using a hydroxyapatite product which could easily break down into fine particles.

Proton magnetic resonance spectroscopy in deep cerebral venous thrombosis

A 63-year-old man developed a severe left frontal headache followed by an acute change of mentality 6 days later. Magnetic resonance imaging revealed bilateral thalamic ischemia. Angiography confirmed the occlusion of deep cerebral veins. Proton magnetic resonance spectroscopy (1H-MRS) of the thalami showed normal N-acetylaspartate (NAA) peak and the presence of lactate peak, indicating a relatively preserved neuronal viability. The patient improved during the follow-up period, and returned to work 45 days after the onset of the disease. With 1H-MRS, prognosis following venous infarctions may be feasible.