SGN nerve filaments develop synapses with IHCs earlier than with OHCs in C57BL/6 mouse inner ear.

OBJECTIVE: To explore the connections between hair cells and spiral ganglion neurons (SGNs) during the development of the C57BL/6 mouse inner ear. MATERIALS AND METHODS: The specimens of C57BL/6 mouse inner ear, from E15 (embryo day 15) to adult mouse, were collected; immunohistochemistry was employed to explore the frozen sections of specimens. RESULTS: The development of cochlea starts sequentially from the basal turn to the apex turn. Morphological development of SGNs occurs mainly from E16 to P12 (postnatal day 12). Hair cells appear from E18 to P12, and inner hair cells (IHCs) develop earlier than outer hair cells (OHCs). The connections between hair cells and SGNs begin to develop during E18-P1, morphologically resemble mature synapses during P8-P12, and completely mature in adult mice. CONCLUSIONS: The genesis of auditory ribbon synapse occurs from E18 to P1. Synchronized with the development of SGNs and hair cells, the functional filaments remain connected to hair cells, while the spare ones get disconnected from the surface of hair cells. Connections between SGN nerve filaments and IHCs occur earlier than those between SGN nerve filaments and OHCs.

Low-level laser therapy alleviates mechanical and cold allodynia induced by oxaliplatin administration in rats.

PURPOSE: Cold and mechanical allodynia caused by oxaliplatin-induced acute peripheral neuropathy frequently occur after drug infusion. Low-level laser therapy (LLLT) has been used to improve pain symptoms associated with various conditions and may have potential as a therapy for oxaliplatin-induced allodynia. The purpose of the present study was to investigate the antiallodynic effect of LLLT in an oxaliplatin-treated animal model by assessing sensory behavioral responses, levels of nerve growth factor (NGF), and transient receptor potential M8 (TRPM8) in dorsal root ganglia (DRG) neurons, as well as substance P (SP) in the spinal dorsal horn. METHODS: Adult male Sprague-Dawley rats each received a total of four doses of oxaliplatin (4 mg/kg, i.p.), injected at 3-day intervals. Following oxaliplatin administration, LLLT (7.5 J/cm(2)) was applied for 12 consecutive days to the skin surface directly above sites where the sciatic nerve is distributed. Behavioral assessments were then performed, followed by immunoassays for NGF, TRPM8, and SP proteins. RESULTS: LLLT relieved both cold and mechanical allodynia induced by oxaliplatin in rats. Oxaliplatin-related increases in protein levels of NGF and TRPM8 in DRG and SP in the dorsal horn were also reduced after LLLT. CONCLUSION: The findings of this study support LLLT as a potential treatment for oxaliplatin-induced neuropathy. Moreover, our findings suggest that SP, TRPM8, and NGF proteins in the superficial dorsal horn and DRG may be involved in an antiallodynic effect for LLLT.

Prostaglandin-D synthetase induces transcription of the LH beta subunit in the primary culture of chicken anterior pituitary cells via the PPAR signaling pathway.

Downstream effects of prostaglandin-D synthetase (PGDS) in a primary culture of chicken (Gallus gallus) anterior pituitary cells were investigated to study how PGDS regulated laying in hens. Either PGDS downstream metabolite, PGD(2) or PGJ(2), elevated LHB mRNA and LHB protein levels in dose- and time-dependent manners, and treatment with arachidonic acid (1 microM) alone upregulated 15-deoxy-Delta(12,14)-PGJ(2) (15-d-PGJ(2); derived from PGJ(2))/PGJ(2), LHB mRNA, and LHB protein levels (P<0.05) in the primary culture of chicken pituitary anterior cells. Transfection of the plasmid Enhanced Green Fluorescent Protein-PGDS plasmid into these cells in medium containing 1 microM arachidonic acid additionally increased 15-d-PGJ(2)/PGJ(2), LHB mRNA, and LHB protein levels (P<0.05). In the hypothalamus/pituitary gland of laying hens, there was a high correlation (r=0.64; P<0.05) between PGDS and the peroxisome proliferator-activated receptor A (PPARA) mRNA level in a high egg production strain, the L2 Taiwan country chickens. In commercial Single-Comb White Leghorn layers, there were high correlation coefficients between PGDS and PPARA (r=0.65; P<0.05) and between PGDS and PPARG (r=0.67; P<0.01) mRNA levels. A broad-range PPARs agonist, GW9578 (5 to 500 nM), enhanced LHB mRNA and LHB protein levels (P<0.05). The PPARA-specific (GW6471) and PPARG-specific (T0070907) antagonists suppressed endogenous LHB mRNA and LHB protein levels (P<0.05); in addition, both antagonists attenuated arachidonic acid-induced LHB mRNA levels (P<0.05) and PGDS-induced (in the presence of 1 microM arachidonic acid) LHB mRNA and LHB protein (P<0.05) levels in the primary culture of chicken anterior pituitary cells. Higher LHB mRNA/LHB protein ratios in PGD(2)-, PGJ(2)-, arachidonic acid-, PGDS-, and GW9578-induced as well as GW6471- and T0070907-suppressed anterior pituitary cells suggested that LHB transcription occurred before translation. In conclusion, PGDS induced LHB transcription and subsequent translation via the PPAR signaling pathway.

Long-term results of Taiwan Pediatric Oncology Group studies 1997 and 2002 for childhood acute lymphoblastic leukemia.

The long-term outcome of 1390 children with acute lymphoblastic leukemia (ALL), treated in two successive clinical trials (Taiwan Pediatric Oncology Group (TPOG)-ALL-97 and TPOG-ALL-2002) between 1997 and 2007, is reported. The event-free survival improved significantly (P=0.0004) over this period, 69.3+/-1.9% in 1997-2001 to 77.4+/-1.7% in 2002-2007. A randomized trial in TPOG-97 testing L-asparaginase versus epidoxorubicin in combination with vincristine and prednisolone for remission induction in standard-risk (SR; low-risk) patients yielded similar outcomes. Another randomized trial, in TPOG-2002, showed that for SR patients, two reinduction courses did not improve long-term outcome over one course. Decreasing use of prophylactic cranial irradiation in the period 1997-2008 was not associated with increased rates of CNS relapse, prompting complete omission of prophylactic cranial irradiation from TPOG protocols, beginning in 2009. Decreased use of etoposide and cranial irradiation likely contributed to the low incidence of second cancers. High-risk B-lineage ALL, T-cell, CD10 negativity, t(9;22), infant, and higher leukocyte count were consistently adverse factors, whereas hyperdiploidy >50 was a consistently favorable factor. Higher leukocyte count and t(9;22) retained prognostic significance in both TPOG-97 and TPOG-2002 by multivariate analysis. Although long-term outcome in TPOG clinical trials is comparable with results being reported worldwide, the persistent strength of certain prognostic variables and the lower frequencies of favorable outcome predictors, such as ETV6-RUNX1 and hyperdiploidy >50, in Taiwanese children warrant renewed effort to cure a higher proportion of patients while preserving their quality of life.

Influences of surgical decompression on the dorsal horn after chronic constriction injury: changes in peptidergic and delta-opioid receptor (+) nerve terminals.

To understand plastic changes in the dorsal horn related to neuropathic pain, we developed a model of decompression in rats with chronic constriction injury (CCI) and investigated corresponding changes in the dorsal horn. At postoperative week 4 (POW 4) of CCI, rats were divided into a decompression group, in which ligatures were removed, and a CCI group, in which ligatures remained. Spinal cords were immunostained for substance P (SP), the delta-opioid receptor (DOR), and calcitonin gene-related peptide (CGRP). Areas of immunoreactive nerve terminals in the dorsal horn were quantified and expressed as the dorsal horn index (immunoreactive areas of the operated side compared with those of the contralateral side). At POW 4, dorsal horn indexes of all of these molecules were significantly reduced in both groups to similar degrees (0.36-0.43). At POW 8, neuropathic pain behaviors had completely disappeared in the decompression group with significant reversal of the dorsal horn indexes compared with the CCI group (0.81+/-0.02 vs. 0.58+/-0.09, P < 0.001 for SP and 0.75+/-0.04 vs. 0.55+/-0.03, P < 0.001 for DOR). In the CCI group, neuropathic pain behaviors became normalized at POW 12 with corresponding changes in dorsal horn indexes for both SP and DOR similar to those of the decompression group. In contrast, changes in the dorsal horn indexes of CGRP were similar in both the CCI and decompression groups throughout the experimental period. These findings suggest that CCI and decompression cause different patterns in peptidergic and DOR (+) nerve terminals in the dorsal horn.

Improved treatment results for childhood acute myeloid leukemia in Taiwan.

To improve treatment results for children with de novo acute myeloid leukemia (AML), we introduced a novel protocol, Taiwan Pediatric Oncology Group-AML-97A, for AML other than acute promyelocytic leukemia (APL), for which modified conventional protocols were used. From January 1, 1997, to December 31, 2002, 141 children younger than 17 years old with de novo AML were enrolled. In total, 117 patients with non-APL AML were treated with induction therapy of idarubicin and cytarabine (Ara-C), postremission therapy with high-dose Ara-C - containing regimens for four monthly courses, and moderate-dose therapy with idarubicin and Ara-C for four monthly courses. The first 19 patients with APL were treated with all-trans retinoic acid, idarubicin and Ara-C, with the remaining five patients receiving all-trans retinoic acid and idarubicin, followed by maintenance therapy for 2 years. Stem cell transplantation was performed in 29 patients in first remission with a similar outcome as chemotherapy alone. The remission rate in the AML-97A study was 90%, the 5-year survival 51 +/- 5.3% (s.e.) and the 5-year event-free survival 50 +/- 4.8%; for APL, these were 100%, 86 +/- 7.0, and 75 +/- 9.8%. For the whole group, the 5-year survival was 57 +/- 4.7% and the 5-year event-free survival 54 +/- 4.4%. The AML-97A regimen was well tolerated.

Pleural effusion and serum soluble fas-ligand levels are elevated in different clinical conditions.

Fas ligand (FasL) plays an important role in the regulation of apoptosis. Soluble FasL (sFasL) is produced by a cleavage of FasL from the cell surface by metalloproteinase. Whether or not sFasL exists or is elevated in the pleural effusion of different etiologies is unknown. The present study is designed to determine pleural effusion and serum sFasL levels under different clinical conditions, and ascertain if there exists a significant difference in the levels found in different clinical conditions, and whether this difference can be used as a tool for differential diagnosis. Soluble FasL levels in the pleural effusion and serum of 103 patients, including 37 with malignant pleural effusion, 24 with uncomplicated parapneumonic effusion, 8 with bacterial empyema, 16 with tuberculous pleurisy, and 18 with transudate effusion (8 with congestive heart failure and 10 with viral liver cirrhosis), were analyzed with ELISA assays. Pleural effusion from patients with bacterial empyema (median 79.4 pg/ml) and TB pleurisy (median 31.9 pg/ml) contained significantly higher amounts of sFasL than the pleural effusion from all other conditions studied (p <0.001). Viral liver cirrhosis had a significantly higher serum sFasL level (median 53.6 pg/ml, p = 0.025, when compared with other patients). Patients with congestive heart failure had the lowest serum sFasL levels when compared with other patients (p = 0.014). There was no significant correlation between pleural effusion sFasL levels and other parameters, such as effusion LDH, cell count, neutrophil, and lymphocyte percentage. In conclusion, soluble FasL is a useful marker for the differentiation of bacterial empyema and TB pleurisy from other disease entities. In addition, the elevation of serum sFasL levels in viral liver cirrhosis can also be used to differentiate cirrhosis from congestive heart failure, in which both effusions are transudate.

Nonmyeloablative allogeneic bone marrow transplantation for orbital granulocytic sarcoma associated with t(8;21)(q22;q22) in acute myeloid leukemia.

We report a nonmyeloablative allogeneic bone marrow transplant (allo-BMT) from an HLA-matched unrelated donor in a case of acute myeloid leukemia (AML), M2 with t(8;21)(q22;q22) and the presence of orbital granulocytic sarcoma (GS), who had residual tumor after conventional chemotherapy. The course of BMT was well tolerated, with no major procedure-related toxicity. The residual orbital GS regressed completely 4 months after BMT. She is currently 19 months post BMT, disease-free. To our knowledge, this is the first reported pediatric patient with AML, GS and t(8;21)(q22;q22) who received a nonmyeloablative allo-BMT.

Prenatal exposure of testosterone prevents SDN-POA neurons of postnatal male rats from apoptosis through NMDA receptor.

The role of N-methyl-D-aspartate (NMDA) receptor in mediating the effect of testosterone exposure prenatally on neuronal apoptosis in the sexual dimorphic nucleus of the preoptic area (SDN-POA) of rats was studied. The endogenous testosterone was diminished by prenatal stress (PNS) or simulated by testosterone exposure (TE) to understand the effect of testosterone on NR(1) (a functional subunit protein of NMDA receptor) expression and neuronal apoptosis. To further study whether the testosterone, after being converted into estradiol, modulates NR(1) expression, 4-androstein-4-ol-3,17-dione (ATD; an aromatase inhibitor) was used to block the conversion of estradiol from testosterone. The expressions of the NR(1) mRNA and NR(1) subunit protein were quantified by RT-PCR and western blotting analysis, respectively. In addition, a noncompetitive antagonist of NMDA receptor, MK-801, was used to find out whether blockage of NMDA receptor affects the naturally occurring apoptosis in SDN-POA. The results showed the following. 1) Expression of perinatal NR(1) subunit protein in the central part of the medial preoptic area of male rats was significantly higher than that of females, especially on postnatal days 1 and 3. 2) The testosterone level of male fetuses on embryonic day 18 was significantly higher than that of females, while the testosterone level of TE females or PNS males was similar to that of intact males or intact females, respectively. 3) The apoptotic incidence of intact male rats was significantly less than that of females, and the apoptosis was stimulated by PNS in male or inhibited by TE in female. 4) The expression of NR(1) subunit protein could be inhibited by PNS or ATD-treatment in male, while stimulated by TE in female. 5) NR(1) mRNA showed no significant difference among intact male, PNS male, ATD-treated male, TE female and intact female rats. 6) The low apoptotic incidence of male rats was significantly increased when NMDA receptor was blocked by MK-801. These results suggest that testosterone, after being converted to estradiol, may prevent the SDN-POA neurons of male rats from apoptosis through enhancing the expression of NR(1) at the posttranscriptional level.

Molecular cloning of the cDNAs for pituitary glycoprotein hormone alpha subunits of two species of duck and their gene regulation.

The cDNAs encoding pituitary glycoprotein hormone alpha subunits (PGHalphas) of two species of duck (Muscovy duck, Cairina moschata and Pekin duck, Anas platyrhynchos domesticus) were cloned and sequenced to better understand the phylogenic diversity and evolution of PGHalpha molecules in vertebrates. Oligonucleotide primers were designed and used for reverse transcription PCR (RT-PCR) amplification of PGHalpha cDNA fragments from total cellular RNA of pituitary glands. The remaining sequences were completed by rapid amplification of the cDNA ends. The nucleotide sequence of isolated PGHalpha cDNA of both ducks are identical, including 81 bp of 5' untranslated region (UTR), 360 bp of coding region, and 272 bp of 3'-UTR followed by a 13 bp poly(A)(+) tract. The total number of amino acids deduced from the cDNA of the duck PGHalpha is 120 with a signal peptide of 24 amino acids and a mature protein of 96 amino acids. PGHalphas of the ducks (order Anseriformes) share 96% homology of amino acid sequence in signal peptide, and 100% homology in mature proteins with chicken, quail and turkey (order Galliformes). Our data thus demonstrate identical inter-order homology of PGHalpha mature protein in birds. Ten cysteine residues, presumably forming five disulfide bonds within the alpha subunit, and four proline residues, presumably responsible for folding of the molecule, are conserved in the alpha subunit of ducks. Northern blot analysis revealed that PGHalpha mRNA is expressed only in the pituitary. In order to study factors regulating the gene expression of PGHalpha mRNA, duck pituitary fragments were incubated with GnRH, TRH, testosterone, or triiodothyronine (T(3)). GnRH and TRH increased, while testosterone and T(3) decreased, PGHalpha mRNA levels. This is the first report in birds of TRH up-regulation and down-regulation by testosterone and T(3) under in vitro conditions. The present study demonstrates both ducks have the same cDNA nucleotide and deduced amino acid sequences in the PGHalpha subunit, exhibiting identical inter-genus homology within the family of Anatidae. The findings from mRNA expression work suggest that hypothalamic GnRH and TRH up-regulate, while testosterone and T(3) down-regulate, PGHalpha gene expression in ducks.

Presence of Epstein-Barr virus latent membrane protein 1 gene in the nasopharyngeal swabs from patients with nasopharyngeal carcinoma.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is the most common head and neck malignancy in southeastern China and Taiwan. Early detection of the local disease followed immediately by proper treatment is essential to increase the cure and survival rates. Because every NPC tumor cell carries Epstein-Barr Virus (EBV) genomes, detection of EBV genomic DNA such as latent membrane protein 1 gene (LMP1) might indicate the presence of NPC. We developed a simple and noninvasive technique of nasopharyngeal swabbing to acquire nasopharyngeal cells for detecting the presence of EBV genome. The aim of this study was to investigate the feasibility and reliability of this technique. METHODS: We collected nasopharyngeal cells by means of a nasopharyngeal swabbing technique and detected the presence of EBV LMP1 with polymerase chain reaction (PCR). Thirty-eight swab specimens were obtained from patients with NPC who were newly diagnosed or were just beginning radiotherapy. Two groups of control subjects were recruited, including 20 patients with other head and neck cancers and eight family members of the NPC patients. An additional group of 65 NPC patients were enrolled in the course of regular follow-up after definitive radiotherapy. RESULTS: All of the samples yielded sufficient DNA for PCR amplification. Thirty-six of 38 NPC swab samples were positive for EBV LMP1, and all the control subjects had swab sample results negative for EBV. All five patients with suspected local recurrence exhibited positive EBV test results. CONCLUSIONS: Demonstration of EBV LMP1 in the nasopharyngeal swab specimens detected NPC with a sensitivity of 94.7% and specificity of 100%. This study confirms the reliability and feasibility of nasopharyngeal swab in the predicting and screening of NPC.

Intestinal metastasis causing intussusception in a patient treated for osteosarcoma with history of multiple metastases: a case report.

Intestinal intussusception caused by metastatic tumors is a very rare condition. Preoperative diagnosis is not easy because of the condition's rarity and because of mild abdominal physical presentation. We report on a patient with osteosarcoma who suffered from abdominal pain and emesis during the period of autologous peripheral blood stem cell transplantation. He had undergone tumor excision and radiotherapy several times prior to autologous peripheral blood stem cell transplantation because of multiple metastases. Intestinal metastasis was suspected initially by computed tomographic scan and sonogram and was proved by surgical resection and pathological findings. Clinicians caring for pediatric patients with osteosarcoma with a history of multiple metastases should consider the possibility of intestinal metastases when equivocal abdominal symptoms develop after intensive chemotherapy.

Molecular cloning of cDNA encoding thyroid stimulating hormone beta subunit of bighead carp Aristichthys nobilis and regulation of its gene expression.

The complementary DNA (cDNA) encoding pituitary thyroid stimulating hormone beta subunit (TSH-beta) of bighead carp was cloned and regulation of its gene expression was investigated for understanding phylogenetic divergence and evolution of TSH molecule. The cDNA was obtained from bighead carp pituitary total RNA by reverse transcription and polymerase chain reaction. Oligonucleotide primers were designed from the sequence of common carp. The full length sequence was then obtained by 3' and 5' rapid amplification of cDNA ends (RACE). The full-length sequence consisting of 3' and 5' untranslated regions was 585 bp long. The predicted amino acid sequence consisted of a signal peptide of 19 amino acid residues and a mature TSH beta subunit protein of 131 residues. The coding sequences of the cDNAs showed variable percentage homologies with those of other teleosts and vertebrate species. The predicted amino acid sequence shared 71% identity with rainbow trout and salmon, 90% with goldfish, 50% with eel and 94% with common carp in the mature protein region. The percentages of identity in the same region in comparison with bovine, porcine, rat, mouse, human and chicken were only 39, 42, 41, 40, 45 and 46%, respectively. TSH beta mRNA expression was found only in the pituitary tissue out of other tissues tested as testis, muscle, brain and heart. For the first time, thyrotropin releasing hormone (TRH) and thyroxine (T4) effects on pituitary TSH mRNA expression were tested in teleosts under in vitro conditions. TRH treatment on pituitary cells increased TSH beta mRNA level, while T4 treatment decreased TSH beta mRNA level. The present study provides a direct evidence, for the first time that TRH directly upregulates TSH beta gene expression in teleosts.

Sexually dimorphic effect of glutamate treatment on cell cycle arrestment of astrocytes from the preoptic area of neonatal rats.

Neurotoxicological studies have indicated that L-glutamate exhibits more pronounced effects on the preoptic area (POA) neurons of male rats than on those of females in the neonatal period. However, no information has previously been available as to whether or not such sexual dimorphism also exists for the effects of glutamate on astrocytes from POA. The present paper reports the differential effects of L-glutamate on astrocytes isolated from POA of neonatal male and female rats. The proliferation of astrocytes was measured by methods of cell count and cell cycle analysis. In addition, the activity of Ca(2+)/calmodulin-dependent protein kinase II (CaM kinase II) was assayed to understand its role in the glutamate-induced disturbance of the cell cycle progression of astrocytes. The results revealed that L-glutamate, at doses of 0.5 and 1.0 mM, inhibited the proliferation of astrocytes derived from male rats more severely than those derived from females. The L-glutamate treatment blocked the cell cycle progression and caused an accumulation of cells in the S phase. The activity of CaM kinase II declined more markedly in astrocytes derived from male rats than in those from females after glutamate treatment. These findings suggest that the proliferation of astrocytes derived from POA of neonatal rats can be inhibited in a sexually dimorphic manner by L-glutamate, possibly through blocking the cell cycle progression and partially related to the inactivation of the CaM kinase II.

Molecular cloning and sequence analysis of the cDNA for thyroid-stimulating hormone beta subunit of Muscovy duck.

The cDNA-encoding thyroid-stimulating hormone beta subunit (TSHbeta) of the Muscovy duck (Cairina moschata) was cloned and sequenced to investigate the phylogenic diversity and evolution of TSH molecules. Oligonucleotide primers were designed and used for reverse transcription and polymerase chain reaction amplification of a TSHbeta cDNA fragment from the total cellular RNA of pituitary glands. The remaining sequence was completed by rapid amplification of cDNA ends. The nucleotide sequence of Muscovy duck TSHbeta cDNA includes 66 bp of 5'-untranslated region (UTR), 402 bp of coding region, and 82 bp of 3'-UTR, followed by an 18-bp poly(A)(+) tract. The total number of amino acids deduced from the cDNA of duck TSHbeta is 134, with a signal peptide of 19 amino acids and a mature protein of 115 amino acids. The homologies of the amino acid sequence of Muscovy duck TSHbeta compared with those of chicken, quail, mammals, amphibian (frog), and teleosts are 97, 98, 68-69, 56, and 42-47%, respectively. To test for tissue specificity of the duck TSHbeta cDNA, total cellular RNA samples from brain, liver, pituitary gland, testis, and thyroid gland were analyzed by Northern blotting. A band, approximately 700 bases, was found in the pituitary gland alone. The pituitary tissue fragments were treated for 24 h in serum-free medium containing thyrotropin-releasing hormone (TRH), triiodothyronine (T(3)), or thyroxine (T(4)). TRH increased and T(3) and T(4) decreased TSHbeta mRNA levels. This study demonstrated that the amino acid sequence of TSHbeta subunits is highly conserved among birds, exhibiting a high degree of inter-order homology, and that hypothalamic TRH upregulates the TSHbeta mRNA expression in duck.

Effects of indoor environmental factors on risk for atopic eczema in a subtropical area.

The objective of this study was to examine the relationship between indoor environmental factors and atopic eczema in a subtropical area. A case-control study was performed using participants from a survey that included 144 school children with atopic eczema and 144 age- and gender-matched controls. The study was confined to 4,164 primary school children aged 6-12 yr attending 8 primary schools in Kaohsiung rural municipalities who participated in the study. Cases of atopic eczema were ascertained by asking whether a physician had ever diagnosed this condition in the child. Information regarding the home environment was obtained using a structured written questionnaire, completed by the parents of the children. Of the many indoor environmental factors included in this study, such as dampness and smoking, none was found to be associated with atopic eczema.

Lactitol-based poly(ether polyol) hydrogels for controlled release chemical and drug delivery systems.

The hydroxyl groups of lactitol were propoxylated to produce poly(ether polyol) (LPEP). The average pK(a) value of hydroxyl groups of the polyol was 1.63. Cross-linked hydrogels were synthesized by esterification with chlorinated poly(ethylene glycol) bis(carboxymethyl) ether (PEGBCOCl). The swelling ratio decreased with increasing cross-linking ratio (PEGBCOCl:LPEP) from 2:1 to 4:1 in the hydrogels and was sensitive to temperature change between 25 and 55 degrees C and concentrations of salt and glucose. The swelling ratio did not change significantly with pH in the range of 4-9. The release profiles of a model active agent, acetylsalicylic acid, from the hydrogels showed that the diffusional release rate had a half-order dependence on time, and the diffusivity decreased with increasing cross-linking ratio. This work demonstrated that LPEP-based hydrogels can be used for controlled delivery of drugs and agrochemicals and the release rates can be controlled with the cross-linking ratio of the hydrogel.

Mechanism and characteristics of protein release from lactitol-based cross-linked hydrogel.

Lactitol-based cross-linked hydrogel was synthesized, and model proteins (alpha-chymotrypsin, beta-lactoglobulin, bovine serum albumin (BSA), and gamma-globulin) were incorporated into the cross-linked hydrogel. The larger-molecular-weight proteins have lower diffusivity (D(e)) in the hydrogel. Increasing temperature accelerated the diffusion rate of proteins; however, the diffusion did not follow the Arrhenius equation at temperatures above 37 degrees C. The swelling ratio of the hydrogel was slightly decreased after heating for 2 h at 37 and 45 degrees C, and significantly reduced after 1 h at 60 degrees C. Therefore, diffusion of beta-lactoglobulin and BSA may be decreased by hydrogel shrinking at temperature over 37 degrees C. The model proteins have high affinities to buffer solution compared to the hydrogel network structure, resulting in high partition coefficients (K > 1) which do not affect the calculation of D(e) values. Incorporated protein release follows the theory of hindered diffusion.

Treatment results of the TPOG-NHL92 protocols for childhood non-Hodgkin's lymphomas in Taiwan: a report from the Taiwan Pediatric Oncology Group (TPOG)

A nation-wide chemotherapeutic trial for childhood non-Hodgkin's lymphoma (NHL) was conducted by the Taiwan Pediatric Oncology Group (TPOG). Four TPOG-NHL92 protocols based on stage and histology were activated in 1992: TPOG-92LD (treatment duration: 8 months) was used for localized (stages I/II) NHL with any histology, 92LB (2 years), 92SNC (5 months), and 92LC (1 year) for advanced (stages III/IV) lymphoblastic (LB), small non-cleaved cell (SNC), and large cell (LC) lymphoma, respectively. From January 1992 through June 1998, 200 children with newly diagnosed NHL from 13 member hospitals of TPOG were enrolled. There were 140 boys and 60 girls. Their ages at diagnosis ranged from 2.4 months to 18.3 years with a median of 8.2 years. There were 54 (27.3%) patients with LB, 94 (47.5%) with SNC including B-cell acute lymphoblastic leukemia (B-ALL), and 50 (25.2%) with LC. Stages I, II, III, and IV (including B-ALL) of the disease comprised 5%, 10%, 43%, and 42% of cases, respectively. There were 176 patients eligible for evaluation of treatment results. The remission rate of induction was 82.4%, induction failed in 22 (12.5%) patients, and nine patients died during induction. As of August 31, 1999, 26 patients relapsed, six died during remission, one patient developed secondary acute myelomonocytic leukemia, and 105 patients remained in continuous remission with a median remission duration of 49 months. The event-free survival (EFS) at 7 years was 63.5%, 61.5% and 65% for LB, SNC, and LC groups (P = 0.8298). The 7-year EFS for stages I/II, III, and IV of the disease was 73%, 68.9%, and 50.3% (P = 0.0212), respectively. We concluded that following the strategy of stratification of therapy, only disease stages had prognostic significance in this study. More efforts are needed to improve our treatment results.

Evaluating the protective role of the olivocochlear bundle against acoustic overexposure in rats by using Fos immunohistochemistry.

Efferent inhibition on the cochlea is suggested as a possible function of the olivocochlear bundle (OCB). Substantial evidence supports the finding that the OCB may protect the inner ear from noise-induced damage. However, there is relatively less known about the effects of noise on the central auditory transmission compared to the effects on the periphery. In the present animal study, two experimental paradigms were designed to analyze the influence of OCB lesion on the central auditory transmission following acoustic overexposure. In order to evaluate the animal's auditory function, its hearing threshold and the tone-evoked Fos expression shown in auditory nuclei were examined. Fos is a protein product of proto-oncogene c-fos. Via appropriate acoustic stimulation, Fos expression reveals the activated neuronal elements along the ascending auditory pathway. Thus, in experiment 1, no exposure sound was introduced and therefore no significant differences were shown in hearing thresholds and Fos expression among all rats, regardless of the status of their OCB. This result indicates that, without acoustic overexposure, OCB lesion caused no significant effect on brainstem auditory transmission. In contrast, in experiment 2, rats were exposed to continuous 8 kHz tones at 85 dB sound pressure level (SPL). A significantly increasing threshold was observed in rats with OCB lesion following an exposure period of 5 or 10 days. In addition, Fos expression was invisible first in rats with OCB lesion following 5-day exposure and almost no Fos expression could be examined in all rats after 10-day exposure. Taken together, the present data demonstrate that damaging the OCB renders an animal more easily vulnerable to acoustic damage than that of rat with intact OCB, and then reduces its cochlear activities, which eventually leads to increasing difficulty to induce tone-evoked Fos expression along the ascending auditory pathway.