Physicochemical and functional properties of goat milk whey protein and casein obtained during different lactation stages

During lactation, goat milk contains colostrum, transitional milk, mature milk, and end milk. The protein present in goat milk during different lactation periods has different characteristics. This study aimed to characterize the protein profile of goat milk samples obtained at different lactation stages and to identify changes in the physicochemical and functional properties of whey protein and casein from goat milk collected at 1, 3, 15, 100, and 200 d after calving. The results demonstrated that the lactation period had a great influence on the physicochemical and functional properties of goat milk whey protein and casein, especially the protein properties of colostrum on the first day after delivery. The denaturation temperature, hydrophobicity, and turbidity of whey protein were significantly higher on the first day postpartum than at other lactation periods. Correspondingly, the colostrum whey protein also had better functional properties, such as emulsification, oil holding capacity, and foaming properties on the first day postpartum than at other lactation periods. For casein, the turbidity, particle size, water holding capacity, and foaming properties on the first day after delivery were significantly higher than those at other lactation periods, whereas the denaturation temperature, oil holding capacity, and emulsification followed the opposite trend. For both whey protein and casein, the 2 indicators of emulsifying properties, namely, emulsifying activity index and the emulsion stability, also followed an opposite trend relative to lactation stage, whereas the changes in foaming capacity with the lactation period were completely consistent with the change of foaming stability. These findings could provide useful information for the use of goat milk whey protein and casein obtained during different lactation stages in the dairy industry.

[Evaluation of computer-aided diagnosis system for detecting dental approximal caries lesions on periapical radiographs]

Objective: To establish and to evaluate a computer-aided system based on deep-learning for detection and diagnosis of dental approximal caries on periapical radiographs. Methods: One hundred and sixty human premolars and molars extracted for orthodontic or periodontal reasons were obtained from Department of Oral and Maxillofacial Surgery, Affiliated Stomatological Hospital, Fujian Medical University. A total of 160 periapical radiographic images were divided into a training dataset (n=80) and a test dataset (n=80). A deep-learning based computer-aided caries diagnosis system was established and trained. The performances of computer-aided diagnosis system and human observer were compared using receiver operating characteristic (ROC) curves, precision-recall (P-R) curves, the area under the curve (AUC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). The AUC values of human observers and caries diagnosis system was compared by using an online statistical tool (SPSSAU 20.0). Chi-square test was used to analyze the differences between human observers and caries diagnosis system (ɑ=0.05). Results: The AUC values of human observers and caries diagnosis system were 0.729 (95%CI: 0.650-0.808) and 0.762 (95%CI: 0.685-0.839), respectively (P>0.05). No significant differences were found for the specificity, PPV and NPV between the caries diagnosis system and human observers (P all>0.05). The caries diagnosis system was significantly more sensitive in detecting dental proximal caries than human observers (P<0.05). For the diagnosis of level-1 caries (caries limited to outer 1/2 of enamel), the sensitivity of human observers and computer-aided detection system were 27% and 77%, respectively (P<0.05). Conclusions: The computer-aided diagnosis system provided similar accuracy as human observers and significantly better sensitivity than human observers, especially for shallow caries in enamel.

Molecular characteristics of MC1R gene in tile-grey plumage of domestic chicken

1. Tile-grey plumage is a unique and rare feather type of local chicken breeds in China, but its genetic mechanism and corresponding genes remain unknown. 2. In order to identify the genetic basis and molecular characteristics of tile-grey plumage, this experiment investigated variations of melanocortin 1 receptor (MC1R) gene in Yunnan Piao chickens with typical tile-grey plumage characteristics in contrast with three Yunnan local breeds as well as two standard breeds with different plumage colour, and analysed the association between genic variation and tile-grey plumage. 3. Through sequencing and comparison of the entire coding region of the MC1R gene, a total of 10 SNP loci were detected, of which eight were non-synonymous mutations that cause amino acid changes. The gene frequency and genotype frequency of the MC1R mutation sites in different breeds and different plumage colour groups revealed that C69T, T212C and A274G were significantly associated with tile-grey plumage. Eighteen haplotypes of the MC1R gene were constructed based on 10 nucleotide variations and eight amino acid variations. Haplotype distribution and the median joining network in breeds and plumage colour groups revealed a main haplotype (hap2) for tile-grey plumage. Hap2 is unique to the tile-grey feather of Piao chicken, and the individuals carrying this haplotype account for 62.96% of the whole tile-grey chicken. 4. The results of this study are of significance for further analysis of the molecular basis of tile-grey plumage and the selective breeding of tile-grey plumage.

[Visual-spatial and temporal characteristics related to infectious Tuberculosis epidemics in Guangxi Zhuang Autonomous Region, 2012-2015]

Objective: To study the spatial and temporal mode of infectious TB transmission in Guangxi Zhuang Autonomous Region (Guangxi). Methods: Data related to infectious TB case (Include smear and/or culture positive patients) in Guangxi were collected from the National Notifiable Disease Reported System (NNDRS) from 2010 to 2015. Spatial-temporal analysis and prediction were performed by SaTScan 7.0.2, GeoDa 1.8.12, R program v 3.3.1 and SPSS 19.0 software, using the time series model, Moran's I global and local spatial autocorrelation (Empirical Bayes adjustment). Kulldorff 's space-time scan statistics displayed by R software was used to identify the temporal and spatial trend of TB. Results: The total number of infectious TB cases, collected from NNDRS was 76 151, and showing a decreasing trend on annual incidence (value of Chi-square for Linear trend=3 464.53, P-value=0.000). The forecast value of TB cases in 2016 was 7 764 (4 971-10 557), with peak in March, analyzed through the Winters'multiplicative model. The Moran's I global Statistics was greater than 0 (0.257-0.390). TB cluster seemed to have been existed for several years. The most significant hot spots seemed to be mainly located in the central and western parts of Guangxi, shown by local spatial autocorrelation statistics and the result from space-time scanning.Counties or districts that located in the east parts of Guangxi presented the low-low relation (significant cold spots). The situation of infectious TB seemed migratory. Conclusions: Our data showed an annual decreasing trend of incidence on infectious TB with temporal concentration in spring and summer. Main clusters (hot spots) were found to be located in the central and western parts of Guangxi. Hopefully, our findings can provide clues to uncover the real mode of TB transmission at the molecular-biological level.

Prospective analysis of KRAS wild-type patients with metastatic colorectal cancer using cetuximab plus FOLFIRI or FOLFOX4 treatment regimens

Cetuximab, a monoclonal antibody targeting epidermal growth factor receptor, has proven to be efficient in the treatment of metastatic colorectal cancer. We made a prospective study of the efficacy and toxicities of cetuximab-combination first-line (FOLFOX4) versus second/third-line (FOLFIRI) chemotherapy in 98 KRAS wild-type patients who had metastatic colorectal cancer. Wild-type KRAS had been identified by direct sequencing. Associations between clinical response/progression-free survival/overall survival/toxicities and cetuximab-combination chemotherapy timing were evaluated. The overall response rate was significantly higher for first-line treatment than for second/third-line treatment (relative risk = 1.707, 95% confidence interval = 1.121-2.598). Both progression-free survival and overall survival indicated significantly longer survival of first-line treatment than second/third-line treatment patients. This study is a validation of a molecular analysis of KRAS wild-type status for the prediction of response to cetuximab-combination chemotherapy for metastatic colorectal cancer patients; its predictive role was less prominent in the second/third-line than in the first-line treatment patients.

Rapid diagnosis of tuberculosis directly from clinical specimens using a gene chip

The aim of this study was to explore a gene chip capable of detecting the presence of Mycobacterium tuberculosis isolates directly in clinical sputum specimens and to compare it with current molecular detection techniques. At first, we selected 13 M. tuberculosis-specific target genes to construct a gene chip for rapid diagnosis. Using the membrane array method, we diagnosed M. tuberculosis by gene chip directly from 246 sputum specimens from patients suspected of having tuberculosis. Among 80 M. tuberculosis complex (MTBC) culture-positive sputum specimens, the MTBC detection rate was 62.5% (50/80) by PCR-restriction fragment length polymorphism (RFLP), 70% (56/80) by acid-fast staining, and 85% (68/80) by the membrane array method. Furthermore, subspecies showed different gene expression patterns in the membrane array. In conclusion, MTBC could be detected directly in sputum by the membrane array method. The rapidity of detection and the capability of differentiating subspecies could make this method useful in the control and prevention of tuberculosis.

External beam radiation therapy for inoperable hepatocellular carcinoma with portal vein thrombosis

Portal vein thrombosis (PVT) in patients with hepatocellular carcinoma (HCC) has a poor impact on prognosis. Many of these tumors may cause intrahepatic and extrahepatic metastases. From January 1991 to December 1996, 41 unresectable HCC patients with PVT underwent transcatheter arterial chemoembolization (TACE) and external beam radiation therapy (EBRT) to the portion of PVT. The irradiated field, with a mean equivalent field size of 6.6 x 7.1 cm2, was localized and simulated by abdominal sonography, angiography and computed tomography. Radiation dose ranged from 36 to 66 Gy (mean dose: 51.4 Gy), in a daily fraction of 1.8 to 2 Gy. The response of EBRT was evaluated by abdominal sonography within 3 months of completion of EBRT. The response rates of the PVT after treatment were 39% for complete response (CR), 41% for partial response (PR), and 19% for no response (NR), respectively. The median overall survival time from start of radiotherapy was 10 months for all patients, 17 months for CR patients, 8 months for PR patients and 4 months for NR patients. By multivariate analysis, response of PVT resulted in a significant improvement in survival. (P = 0.001) There was no occurrence of severe complication of radiation-induced liver disease. The results obtained with combined treatment modality of EBRT and TACE in the treatment of HCC patients with PVT are encouraging.

Chromium speciation in residues after sequential extraction of a thermally treated sludge analog

XANES fitting indicates that non-Cr2O3 form of Cr(III), transformed from CrO3 by four-hour heat application at 1100 degrees C, is the key species sorbed onto or lattice-diffused into kaolin matrices that exhibits strong leaching resistance to sequential extraction using various combined solutions including HNO3, H2O2, and HF. The EXAFS spectra are all in agreement with the XANES results. It is suggested that some Cr2O3 might have reacted with kaolin to form new compounds such as Cr2O3 x Al2O3 x 2SiO2 to account for the slight dissimilarity between the EXAFS spectra of samples and that of Cr2O3.

Simultaneous detection of C282Y and H63D hemochromatosis mutations by dual-color probes

BACKGROUND

Hemochromatosis is a common genetic disease, affecting one in every 200 individuals in the United States. A PCR assay was designed using fluorescent melting curve analysis to simultaneously detect the G845-->A (C282Y) and C187-->G (H63D) mutations. The G845-->A and C187-->G loci are distinguished by color, and mutant alleles are distinguished from wild type by probe melting temperature (Tm).

METHODS AND RESULTS

The probe sets used two fluorophore pairs, fluorescein with LCRed 640 for G845-->A and fluorescein with LCRed 705 for C187-->G. The probes, complementary to the mutant allele, dissociate from the product at specific Tms. Wild-type alleles form mismatches with the probes, reducing the Tms by 6 degrees C (G845-->A) and 10 degrees C (C187-->G). One of 133 samples had a Tm shift 4 degrees C less than the wild-type Tm for the G845-->A locus. Sequencing confirmed the sample to be homozygous for G845-->A and heterozygous for a C-->A substitution at position 842 (C842-->A), substituting lysine for threonine.

CONCLUSIONS

Multiplexing by color and Tm allows for simultaneous genotyping of each mutation. A novel base-pair alteration was detected in cis with a G845-->A mutation.

Dopamine-secreting glomus vagale: a case report and histopathologic correlation

BACKGROUND

Catecholamine secretion by head and neck paragangliomas is uncommon. Dopamine secretion by these tumors has not routinely been assessed. This case report describes a dopamine-secreting glomus vagale and evaluates seven other paragangliomas immunohistochemically for their ability to synthesize dopamine.

METHODS

Light microscopic and immunohistochemical studies were performed on eight tumors, and biochemical testing for serum/urine catecholamines was performed on two patients.

RESULTS

One patient (case report) had elevated serum dopamine which corrected following surgery. Five tumors stained strongly positive for the presence of tyrosine hydroxylase, the critical enzyme in the biosynthesis of dopamine.

CONCLUSION

This case report describes the ability of a glomus vagale to secrete dopamine. Other paragangliomas express the enzymatic machinery necessary to begin catecholamine synthesis. Now that dopamine is routinely screened during catecholamine determination, other cases may be identified.

Tensile and Tear Behavior of Anisotropic Double Networks of a Black-Filled Natural Rubber Vulcanizate

Double networks of a black-filled natural rubber composition have been prepared by partially curing a sheet, stretching it, and then completing cure. Upon release, a double network retracts to a residual extension ratio, αr. Samples cut perpendicular to the stretch direction have stress—strain responses like the isotropic single network, while parallel samples have enhanced stiffness and tensile strength, and reduced extensibility. Tensile strength is rather weakly dependent on αr. Tear strengths of the double networks, determined using edge-cut strip specimens, exceed that of the single network for low αr. However, when αr is high, double networks have very low tear strengths. Consistent with previous studies, high tear strengths are associated with extensive longitudinal cracking.

Simultaneous multiple viral infections in childhood acute lower respiratory tract infections in southern Taiwan

Thirty paediatric patients with acute lower respiratory tract infections (ALRI) caused by simultaneous multiple viral infections (SMV) in a 3-year interval were reviewed. Twenty patients were infected with two viruses simultaneously; nine patients with three viruses; and one patient with four viruses. The frequency of individual viruses were: adenovirus, 18 (60 per cent); respiratory syncytial virus, 7 (23 per cent); influenza virus type A, 6 (20 per cent); influenza virus type B, 15 (50 per cent); parainfluenza virus type 1, 11 (37 per cent); parainfluenza virus type 3, 13 (43 per cent). There was no difference between the clinical presentations of ALRI with SMV and those of ALRI with a single virus. In conclusion, SMV was not uncommon in children with ALRI; the clinical presentations of multiple viral infection were similar to those of single viral infection.

Pharmacokinetics and electrocardiographic effect of ebastine in young versus elderly healthy subjects

The objective of this study was to compare the single- and multiple-dose pharmacokinetics and electrocardiographic effect of a 10-mg oral dose of ebastine in elderly (ages, 65-85 years) and young (ages, 18-35 years) healthy volunteers. Thirty-seven subjects completed this randomized, double-blind, multiple-dose, placebo-controlled, parallel group study. The elderly group consisted of 18 subjects, with 13 subjects receiving 10 mg ebastine and 5 receiving matching placebo. The young group consisted of 19 subjects, with 13 subjects receiving 10 mg ebastine and 6 receiving matching placebo. On study days 1 and 3 through 10, each subject received a single 10-mg dose of ebastine or matching placebo in the morning with a standard breakfast. No drug was administered on study day 2 because of pharmacokinetic sampling. Blood samples were collected at selected times postdose on study days 1, 2, and 10. Plasma samples were analyzed for ebastine and its active metabolite, carebastine, using a validated high-performance liquid chromatography method. No plasma ebastine concentrations were detected, suggesting essentially complete metabolic conversion of ebastine to its metabolites. Analysis of variance showed no statistically significant differences between young and elderly single- and multiple-dose carebastine pharmacokinetics with respect to area under the plasma concentration-time curve, maximum concentration (Cmax ), terminal elimination rate constant, apparent oral clearance, or apparent volume of distribution. The mean time of maximum concentration value for young subjects was 1 hour longer than that for elderly subjects after single-dose administration but was comparable after multiple-dose administration. Within-group comparisons of both the young and elderly showed that pharmacokinetics between single dose and steady state were not statistically different. However, the mean steady-state carebastine Cmax values were approximately twofold greater than the mean Cmax values obtained after single-dose administration. A twofold increase in Cmax values between single-dose and steady-state administration is predicted for drugs such as carebastine, because its input interval is approximately equal to its elimination half-life. Twelve-lead electrocardiography was performed before dosing on day 1 and repeated 4 hours postdose on days 1, 5, and 10. Twenty-four hour Holter monitoring was also performed before and at the end of the study. No clinically relevant findings were found by electrocardiography or Holter monitoring between ebastine and placebo in the elderly and young subjects.

The alternative H-ras protein p19 displays properties of a negative regulator of p21Ras

In previous work, we demonstrated that expression of mammalian H-ras genes is controlled by alternative splicing. Mutational analyses indicated that most H-ras premessenger RNA (pre-mRNA) is not processed into mRNA for the usual p21Ras protein, but is recognized instead for processing through an alternative pathway that would produce mRNA for a hypothetical p19Ras protein, which would be a truncated form of p21 with a different carboxyl-terminus. We have raised the possibility that p19 could be a negative regulator of p21, but only small amounts of mature p19 mRNA could be detected and we had no evidence that the protein could be made. We now show by transient and stable transfection experiments that p19 can be produced from complementary DNA (cDNA) expression vectors in human 293 cells, which express early adenoviral genes. However, p19 cDNA inhibited the formation of drug-selected colonies of Rat-1 cells and surviving colonies produced little p19. Colony formation and p19 expression were increased when the cDNA had mutations in the putative effector domain of p19 or when oncogenes believed to act downstream of p21Ras, such as adenoviral E1A, were included in the transfections. These results indicate that p19 can act as an inhibitor of p21. We also show that authentic p19 can be abundantly expressed in 293 cells from H-ras gene constructs with mutations favoring the alternative splicing pathway, which suggests that regulated splicing could support overproduction of p19 under natural conditions. Our work indicates that mutations abolishing alternative H-ras splicing may not only contribute to oncogenesis by increasing the production of p21, but also by interfering with the production of an antiproliferative H-ras activity.

A new anthracycline antibiotic, IT-62-B, converts the morphology of ras-transformed cells back to normal: taxonomy, fermentation, isolation, structure elucidation and biological characterization

A new antibiotic, IT-62-B was isolated from the culture broth of Streptomyces sp. IT-62 by extraction with acetone and then with ethyl acetate, followed by conventional column chromatography using silica gel, Sephadex LH-20 and silica ODS. Its structure (C39H47NO15, MW 769) was determined by 1H, 13C NMR, MS, IR and UV spectrometric techniques to be a new member of the baumycin-group anthracyclines. It showed moderate activity against Gram-positive bacteria and had antitumor activity against various tumor cell lines. Further, antibiotic IT-62-B converted the morphology of ras-transformed NIH3T3 cells and T-cells back to normal at concentrations inhibiting cell growth by 30% or more.

Molecular cloning and functional expression of cDNAs encoding a human Na+-nucleoside cotransporter (hCNT1)

We report identification of a new human nucleoside transporter protein by molecular cloning and functional expression of its cDNA. Previously, we used expression selection in Xenopus oocytes to isolate a cDNA from rat jejunal epithelium encoding the pyrimidine-selective Na+-dependent nucleoside transporter rCNT1 (Q.-Q. Huang, S. Y. M. Yao, M. W. L. Ritzel, A. R. P. Paterson, C. E. Cass, and J. D. Young. J. Biol. Chem. 269: 17757-17760, 1994). cDNAs for a human homologue of rCNT1, designated hCNT1, have been isolated from human kidney by hybridization cloning and reverse transcriptase polymerase chain reaction amplification strategies. hCNT1 was 83% identical to rCNT1 in amino acid sequence and exhibited the transport characteristics of an Na+-dependent nucleoside transporter with selectivity for pyrimidine nucleosides and adenosine when expressed in Xenopus oocytes. Deoxyadenosine, which undergoes net renal secretion, and guanosine were poor permeants. hCNT1 did, however, transport 3'-azido-3'-deoxythymidine. This is the first demonstration that members of the CNT family exist in human cells and provides evidence of their involvement in the renal transport of physiological nucleosides and nucleoside drugs. The hCNT1 gene was mapped to chromosome 15q25-26.

The effect of food on the bioavailability of ebastine

Two studies were performed to characterize the influence of food on the bioavailability of the current formulation of ebastine tablets. Study 1 was an open label, randomized, three-period, crossover food effect study where 18 healthy male volunteers received 10 mg ebastine after an overnight fast, a low-fat breakfast, and a high-fat breakfast. Study 2 was an open label, randomized, two period crossover food effect study where 12 healthy male volunteers received 20 mg ebastine after both an overnight fast and a high-fat breakfast. Plasma samples were obtained at selected times and analyzed for ebastine and carebastine, the active metabolite of ebastine, using a validated high-performance liquid chromatography assay. Biopharmaceutic parameters for carebastine, area under the plasma concentration-time curves (AUC (0-infinity)), and maximum plasma concentrations (C ( max ) ), were estimated using noncompartmental techniques and analyzed for statistical differences. AUC (0-infinity) and C(max estimates were 40%-50% and 30%-40% higher under fed conditions as compared with fasting conditions. The time to reach maximum concentrations (T(max)), the terminal elimination rate (K(e) ), and the half-life (t(1/2) ) were not significantly altered by the ingestion of a low-fat or high-fat meal. Statistical analyses of the natural logarithmic transformed data for AUC ((0-infinity) and C(max) also demonstrated significant differences between fasted and fed (low-fat and high-fat) conditions. This indicates that food had a statistically significant effect on the rate and extent of carebastine formation. Therefore, it may be concluded that administration with food maximizes the bioavailability of carebastine.

[The effects of gastrin-releasing peptide (GRP) and vasoactive intestinal polypeptide (VIP) on the prolactin (PRL) gene transcription of pitutitary PRL releasing tumor of rat]

The effects of gastrin-releasing peptide (GRP) and vasoactive intestinal polypeptide (VIP) on the prolactin gene transcription of cultured pituitary of male Sprague-Dawley (SD) rats PRL releasing tumor (PPRT) (induced by estradiol) cells were studied. The PRL mRNA levels were determined by in situ hybridization of cytoplasmic RNA with a DIG-labeled PRL cDNA probe. PRL mRNA levels didn't change when the PPRT cells were incubated with 10(-8) mol/L or 10(-7) mol/L GRP for 24 h, but decreased by 20% when GRP was increased to 10(-6) mol/L (P < 0.05). The PRL mRNA level increased to 1.60, 2.10, 2.21 times of the control group when the PPRT cells were respectively incubated with 10(-8), 10(-7), 10(-6) mol/L VIP for 24 h (P < 0.05). The PRL mRNA level didn't change when the PPRT tumor cells were incubated with 10(-8) mol/L E2 for 48 h, but did increase to 2.80 and 2.92 times of the control group respectively when 10(-7) mol/L and 10(-6) mol/L E2 were used. The results above indicated that GRP and VIP exert an inhibitory and a stimulatory effect on RPL gene transcription respectively, while the stimulatory action of E2 on PRL secretion is a direct one.

Mitochondrial NADH-coenzyme Q reductase deficiency in Leigh's disease

A 4 1/2-month-old girl suffered from psychomotor retardation, generalized hypotonia, poor feeding, hyperreflexia, nystagmus, optical atrophy and choreoathetosis from the age of 3 months. Her blood lactate level was elevated to 40 mg/dL. Magnetic resonance imaging of her brain showed low T1 and high T2 signal intensities in the bilateral putamen, thalamus, red nuclei, substantia nigra, superior and inferior colliculi, cerebral peduncles and periaqueductal lesions. Muscle histochemistry and electron microscopic examinations were all normal except for variation in fiber size showing a myopathic change. An assay of muscle mitochondrial respiratory enzyme activities revealed a deficiency of NADH-coenzyme Q reductase. Molecular analysis did not reveal the putative T to G transversion at the nucleotide 8,993 of mitochondrial DNA in muscle biopsies. Leigh's disease was indicated by the clinical and radiologic manifestations. The patient died at 10 months of age from pneumonia and respiratory failure. There have been only sporadic reports of patients with Leigh's disease in Taiwan, and, to our knowledge, this is the first documented case of a Taiwanese patient with mitochondrial NADH-coenzyme Q reductase deficiency.

Electrocardiographic findings in children with spinal muscular atrophy

Most of the patients in this study with spinal muscular atrophy were found to have tremors of the isoelectric line in the electrocardiogram (ECG) tracings. There were a total of 47 cases of SMA (mean age 40.8 months). All three types of SMA had a similar incidence (about 80%) of tremors in the tracings (p = 0.885). In 7 cases the ECG tremors had an intermittent pattern. ECG tremors were commonly found in the majority of SMA patients and this finding, though non-specific, may suggest a possible SMA diagnosis.

Interleukin-1 alpha stimulates osteoclast formation from peripheral blood monocytes and increases osteoclastic activity

BACKGROUND

Interleukin-1 (IL-1) is produced by monocytes and marrow stromal cells and can stimulate bone resorption in tissue culture. In addition, IL-1 can induce osteoclast-like cell formation in long-term bone marrow culture. However, whether IL-1 can increase osteoclast formation by stimulating fusion of peripheral blood monocytes is not clear. In addition, the precise effect of IL-1 on osteoclastic activity is still not well known.

METHODS

Using the bioassay of osteoclast formation, osteoclast-free fetal calvariae were harvested from 14-day timed-pregnant Sprague-Dawley rats and cultured in BGJb medium for 10 days. On the 10th day, mononuclear cells were obtained from peripheral blood of 8-week-old female Sprague-Dawley rats through cardiac puncture and Ficoll-Paque density gradient separation method and co-cultured with osteoclast-free developing bone explant. On the same day, various concentrations of IL-1 alpha (1,10 or 100 U/ml) were added daily in the experimental dishes while only BGJb medium was added in the controls. In addition, 45Ca release assay and quantitation of nuclei per osteoclast were performed to evaluate the effect of IL-1 alpha on osteoclastic activity.

RESULTS

Ten days after adding monocytes, there were 14.25 osteoclasts in the control, without IL-1 alpha; with 1 U of IL-1 alpha, there were 14.75 osteoclasts; with 10 U of IL-1 alpha, there were 18.00 osteoclasts; with 100 U of IL-1 alpha, there were 20.75 osteoclasts. In addition, IL-1 alpha stimulated the release of 45Ca and increased the number of average nuclei per osteoclast dose-dependently, indicating a significant increase in bone resorption.

CONCLUSIONS

IL-1 alpha could increase osteoclast formation by stimulating the fusion of peripheral blood monocytes. In addition, IL-1 alpha is a potent stimulator of osteoclastic activity.

Development and in vitro-in vivo evaluation of a multiparticulate sustained release formulation of diltiazem

PURPOSE

To develop and evaluate the in vitro/in vivo performance of diltiazem sustained release pellets that were prepared by the Wurster column process.

METHODS

Pellets containing diltiazem were prepared by spraying a slurry of micronized diltiazem hydrochloride, pharmaceutical glaze and alcohol onto an appropriate mesh fraction of nonpareil seeds using the Wurster column. A two-step drug layering process was used to increase drug loading from 60% to 75%. The oven-dried diltiazem basic pellets were coated with ethylcellulose/dibutyl sebacate coating solution to yield diltiazem sustained release pellets. An open, randomized Latin square, three-way crossover clinical study was used to evaluate the in vivo performance of the coated product.

RESULTS

Altering the mesh fraction of the starting nonpareil seeds for this layering process was found to affect the release characteristics of drug from the pellets. An oven-drying step was required to stabilize the diltiazem basic pellets. The thicker the drug loading layer the longer the oven drying is needed to stabilize the pellets. The diltiazem sustained release pellets produced by these methods displayed sustained release dissolution profiles both in vitro and in vivo. Diltiazem basic pellets coated with a 0.6% ethylcellulose/dibutyl sebacate coating showed a different rate of absorption (lower Cmax and higher Tmax) and the same extent of absorption as compared to Cardizem tablets.

CONCLUSIONS

Clinical data confirmed that this formulation approach is an effective means to produce a diltiazem sustained release product.

Relationship between left atrial pressure and atrial natriuretic peptide in children with cardiac disease

To evaluate the relationship between atrial pressure and the concentrations of atrial natriuretic peptide (ANP) in plasma of children with cardiac disease combined with increased left atrial loading. We extracted plasma ANP through a Sep-Pak C18 cartridge and proceeded to radioimmunoassay. Of the nine children, aged from 20 days to 10 years, cardiac diseases included transposition of the great arteries (four cases), ventricular septal defect (three cases), patent ductus arteriosus (one case) and mitral regurgitation (one case). The concentrations of ANP in plasma in the left atrium were greater than in the inferior vena cava, and the concentrations of ANP in plasma in the inferior vena cava correlated significantly with the mean left atrial pressure (r = 0.89, p < 0.01), and the concentrations of ANP in plasma in the left atrium correlated significantly with the mean left atrial pressure (r = 0.85, p < 0.01). This study indicated that left atrial pressure may have an important influence on secretion of ANP in various cardiac conditions.

Relationship between hemodynamics and plasma atrial natriuretic peptide in children with ventricular septal defect or patent ductus arteriosus

To evaluate the relationship between concentrations of ANP in plasma of the right-sided central circulation and hemodynamic parameters in congenital heart disease with left-to-right shunt. We enrolled 20 children aged from 1 month to 4.8 years with ventricular septal defect (VSD) or patent ductus arteriosus (PDA). The concentrations of ANP in plasma were extracted through a cartridge (Sep-Pak C18) before being measured by radioimmunoassay. Significant increased concentrations of ANP in plasma from inferior vena cava (117.6 +/- 18.1 pg/mL), right atrium (160.6 +/- 21.6 pg/mL) to pulmonary artery (PA) (253.4 +/- 38.8 pg/mL) were recognized. In VSD (n = 10) and PDA (n = 10), the concentrations of ANP in plasma from the inferior vena cava correlated significantly with the ratio of pulmonary to systemic blood flow (Qp/Qs) (r = 0.69, p < 0.05; r = 0.94, p < 0.01 respectively), the systolic pulmonary artery pressure (r = 0.90, p < 0.01; r = 0.93, p < 0.01 respectively), the diastolic pulmonary artery pressure (r = 0.76, p < 0.02; r = 0.68, p < 0.05 respectively), and the mean pulmonary artery pressure (r = 0.88, p < 0.01; r = 0.87, p < 0.01 respectively). The concentrations of ANP in plasma from the pulmonary artery also correlated significantly with the Qp/Qs (r = 0.81, p < 0.01; r = 0.87, p < 0.01 respectively). The results indicated that left atrial volume loading may have an important influence on secretion of ANP in some congenital heart disease with left to right shunt.

[Regulatory role of galanin on prolactin and beta-endorphin release from anterior pituitary lobe of rat]

The role of brain-gut peptide galanin in the regulation of prolactin (PRL) and beta-endorphin (beta-EP) release from anterior pituitary lobe was studied in vivo in conscious male rats and in vitro with cultured anterior pituitary cells of the rat. Galanin (1 microgram or 3 micrograms/rat) injected into the third cerebral ventricle of rats produced highly significant, dose-related increases of PRL resting secretion, but did not alter resting secretion of beta-EP and restraint stress-induced release of PRL and beta-EP. However, galanin (0.05, 0.5 and 1.0 micrograms/5 x 10(5) cells.ml-1) induced highly significant, dose-related increase of beta-EP secretion from dispersed anterior pituitary cells, but failed to alter significantly PRL secretion from the cultured cells. These results indicate that central galanin has a stimulatory role in pituitary PRL resting secretion via the hypothalamus, whereas peripheral galanin stimulates beta-EP secretion only via direct action of this peptide in anterior pituitary cells.

[Somatomedin-C in infantile nutritional assessment with comparison with prealbumin, insulin and growth hormone]

Somatomedin-C (Sm-C) is also called insulin like growth factor I (IGF-I). It has insulin-like biological effects and serves as an anabolism-related mediator of growth hormone. Most Sm-C is synthesized in liver cells. There are decreased blood levels of Sm-C, prealbumin and insulin, but increased blood levels of growth hormone in the adult with malnutrition. We simultaneously measured the blood levels of the above four peptides in infants aged one month to one year. They were divided into four groups: normal, first class malnutrition, second class malnutrition and third class malnutrition. They were classified according to the Value of Nutrition Index. The utility of Sm-C measurement was compared to that of the measurements of prealbumin, insulin and growth hormone in the nutritional assessment. The results revealed that the blood level of Sm-C decreased more in the cases of severe malnutrition (Normal group: male 361.2 +/- 158.9 mU/ml (n = 18), female 499.3 +/- 227.8 mU/ml; (n = 19); First class malnutrition group: 256.9 +/- 81.1 mUU/ml (n = 17); Second class malnutrition group: 169.5 +/- 43.5 mU/ml (n = 15); And third class malnutrition group: 76.2 +/- 26.5 mU/ml (n = 18)). The blood level of prealbumin decreased more in the cases of severe malnutrition (Normal group: 17.8 +/- 2.1 mg/dl (n = 37); First class malnutrition: 11.8 +/- 3.5 mg/dl (n = 17); Second class malnutrition: 11.8 +/- 3.5 mg/dl (n = 15); And third class malnutrition: 9.7 +/- 2.4 mg/dl (n = 18)).(ABSTRACT TRUNCATED AT 250 WORDS)

Modified filter synthetic discriminant functions for improved optical correlator performance

By the filter modulation operator N, the modified filter synthetic discriminant function permits advantageous preprocessing of individual training-set images that are used in a linear combination to construct the filter synthetic discriminant function, which applies a modulation operator M to the synthetic discriminant function. A relaxation algorithm is used to satisfy the equal correlation peaks rule in the correlator output plane. As the filter modulation operators M and N can be given any functional form, the modified filter synthetic discriminant function design proposed is sufficiently general to be described as a unified filter modulation synthetic discriminant function design.

Study on the children of Kaohsiung with acute viral infection of lower respiratory tract by direct immunofluorescence assay

This study retrospectively reviewed those pediatric patients of acute lower respiratory tract infection with positive virus identification by direct immunofluorescence assay (Direct IF) from Jan, 1992 to Dec, 1993. One hundred and eighteen patients with 133 positive Direct IF results (107 cases with single virus identified, and 11 cases with more than one) were included. The sex ratio was 1.6:1 with males predominant; age, 22.1 (1 approximately 154.8) (months); duration of admission, 5.7 (1 approximately 69) (days); peripheral white blood cell count, 10,600 +/- 3,800/mm3; C-reactive protein, 17.0 (0 approximately 163.3) mu/ml; body temperature, 37.1 +/- 1.1 degrees C in those cases with single virus. The symptoms were cough 105 cases (98.1%), rhinorrhea 46 cases (43.0%), dyspnea and/or tachypnea 43 cases (40.2%) and diarrhea 15 cases (14.0%). The viruses identified were: Adenovirus (52 cases, 39.1%). Influenza B (45 cases, 33.8%), Parainfluenza 1 (28 cases, 20.1%), Parainfluenza 3 (19 cases 14.3%), Respiratory Syncytial virus (17 cases, 12.8%), and Influenza A (9 cases, 6.8%). The seasonal incidence rates were spring (49 cases, 36.8%), summer (46 cases, 34.6%), autumn (23 cases, 17.3%), and winter (15 cases, 11.3%). The results showed much similarity with others, except the commonest viral type (Adenovirus in this study; Respiratory Syncytial virus in others) and the seasonal incidence rate (higher in spring and summer in this study but not in others). In conclusion, most children with acute viral lower respiratory tract infection had an uneventful course and Direct IF is a reliable method for viral detection in that disease.

Effects of smoking and drinking habits on urinary o-cresol excretion after occupational exposure to toluene vapor among Chinese workers

The relationship between the time-weighted average intensity of exposure to toluene and o-cresol concentration in shift-end urine was investigated in nearly 500 factory workers of both sexes in China, together with a similar number of nonexposed control subjects. Toluene concentration (25 ppm as geometric mean and 550 ppm as the maximum) was monitored by diffusive sampling using carbon cloth as adsorbent followed by gas chromatographic (GC) analysis. o-Cresol (up to 7 mg/l) was measured by GC after acid hydrolysis of samples. Urinary o-cresol levels correlated significantly (r = 0.69-0.77; p < 0.01) with toluene exposure in men, women and the two sexes in combination, regardless of correction for urine density. When compared with hippuric acid, however, o-cresol was less sensitive as an indicator of exposure to toluene and is not a suitable biological marker for detecting low level toluene exposure. Since urinary o-cresol level was significantly reduced by smoking, drinking, and the two habits combined, it cannot be considered reliable as an indicator of exposure to toluene.

Q-switched ruby laser treatment of benign pigmented lesions in Chinese skin

The Q-switched ruby laser has been demonstrated as an effective choice of treatment for a range of benign pigmented lesions. Its wavelength of 694 nm enables deep penetration of the skin allowing the treatment of both epidermal and dermal lesions. However, this wavelength is selectively absorbed by melanin thereby enabling efficient targeting of the lesion's melanocytes. By utilising a Q-switched pulsewidth of 25 nanoseconds, thermal conduction into surrounding tissues is minimised. Lesions such as nevus of Ota, chloasma, lentigines and cafe au lait have been successfully treated with energy densities ranging from 6 to 12 J/cm2. Four case histories are described in this report. The clinical evidence indicates that pigmented lesions in Chinese skin must be treated with energy densities higher than those used in Caucasian skin to minimise the incidence of hyper-pigmentation. Typically, lesions require a small number of treatments, usually within the range one to six, to effect complete removal. The technique is easy to apply, with no need for anaesthesia, in many cases.

Exposure of workers to a mixture of toluene and xylenes. I. Metabolism

The urinary excretion of hippuric acid and methylhippuric acid was studied in workers (233 subjects; 122 men and 111 women) exposed to toluene and xylenes in combination and in non-exposed controls (281 subjects; 141 men and 140 women) recruited from the same factories or factories of the same regions. Smoking and drinking habits of the subjects were obtained by medical interviews. From each worker, one urine sample was collected at the end of a shift and analysed for hippuric and methylhippuric acids by high performance liquid chromatography. Air samples for the estimation of toluene and xylenes were collected with diffusive personal samplers. There was a linear correlation between the time weighted average exposure either to toluene or xylene isomers and the concentrations of hippuric acid or methylhippuric acid isomers in urine. Essentially no difference was found in the correlation between quantitative exposure and excretion in the three xylene isomers. Comparison of the slopes of regression lines indicated the absence of metabolic interaction between toluene and xylenes at the measured concentrations. The metabolism of toluene and xylenes was significantly reduced among smokers or drinkers compared with non-smokers and non-drinkers.

The uses and limitations of DNA flow cytometry in stage IB or II cervical carcinoma

BACKGROUND

The role of flow cytometry in predicting prognosis for cervical carcinoma remains unclear.

METHODS

Flow cytometric analysis was performed on tissues, fixed in formaldehyde solution and embedded in paraffin, from 411 patients with Stage IB or II cervical carcinoma who had been treated with radical abdominal hysterectomy and bilateral pelvic lymphadenectomy.

RESULTS

DNA aneuploid-multiploid tumors were found in 37.5%, tetraploid in 4.6%, and diploid-peridiploid in 57.9%. Five-year recurrence-free survival rates of the three groups were 74.3%, 77.8%, and 76.4%, respectively (P > 0.05). DNA aneuploidy and DNA index (DI) of greater than 1.3 were highly correlated to parametria extension. In univariate analysis, pelvic lymph node metastases, stage, parametrial extension, depth of cervical stromal invasion, tumor size, and DI (1.3, 1.4, 1.5 as breakpoint) were significant prognostic factors. DNA ploidy, S-phase fraction, and S-G2M fraction were not significant. In multivariate analysis, DI of greater than 1.3, pelvic node metastases, clinical Stage II, and depth of stromal invasion greater than two-thirds of full cervical thickness were independent and significant variables. The prognostic index (PI), defined by the model, was able to categorize the patients into three distinct risk groups. The 5-year recurrence free survival rates of the low-, intermediate-, and high-risk groups were 89.5%, 73.0%, and 58.9%, respectively (P < 0.0001).

CONCLUSIONS

The prognostic value of the DI as a single variable is promising and warrants additional investigation to establish its appropriate use.

[Pancreatic polypeptide in the control of beta-endorphin and prolactin release from rat anterior pituitary in vivo and in vitro]

This study was designed to examine the possible effects of pancreatic polypeptide (PP) on beta-endorphin (beta-EP) and prolactin (PRL) release from rat anterior pituitary in vivo and in vitro. Injection of 0.5 microgram or 2.0 micrograms PP into the third ventricle of the brain (3rd v.i.) produced a significant decrease of the beta-EP and PRL resting secretion. 0.5 microgram PP (3rd v.i.) did not affect restraint stress-induced release of beta-EP, but partially lowered stress induced release of PRL. 2.0 micrograms PP (3rd v.i.) partially reduced restraint stress-induced release of beta-EP and completely suppressed stress-induced release of PRL. In order to investigate a possible direct action of PP on beta-EP and PRL secretion from the anterior pituitary gland, we incubated dispersed anterior pituitary cells with synthetic PP (0.05, 0.625 and 1.00 micrograms) for 1 n, the secretion of beta-EP was not affected at any dosage tested, but 0.625 and 1.00 micrograms PP significantly decreased the PRL secretion. These data indicate that PP may have an inhibitory role in the control of beta-EP secretion at the level of the hypothalamus, and an inhibitory role in the control of PRL secretion at the level of either hypothalamus or anterior pituitary.

Symptoms and signs in workers exposed predominantly to xylenes

Surveys were conducted in factories in China where workers were engaged in the production of rubber boots or plastic-coated wire or in printing work, and were exposed to xylene vapors. Based on the data on exposure as monitored by personal diffusive sampling, 175 xylene-exposed workers (107 men and 68 women) were selected as those (1) who underwent all examinations and (2) for whom the sum of the three xylene isomers accounted for 70% or more of the total exposure (on a ppm basis). The intensity of exposure was such that the sum of the three isomer concentrations was 14 ppm as a geometric mean and 21 ppm as an arithmetic mean. As controls, 241 nonexposed workers (116 men and 125 women) were recruited either from the same factories or from factories in the same regions. There was an increased prevalence of subjective symptoms in the exposed workers which were apparently related to the effects on the central nervous system and to the local effects on the eyes, the nose, and the throat, although dose-dependency of the symptoms was evident in only a limited number of cases, possibly because the intensity of exposure was rather low. It was further observed that the findings of hematology and serum biochemistry in respect of liver and kidney functions were generally negative, showing that xylenes are not toxic to the hematopoietic organs, the liver, or the kidney.

Effect of hamster liver passage on the isoenzyme patterns of Entamoeba histolytica

The effect of hamster liver passage on the isoenzyme patterns of isolates of Entamoeba histolytica was investigated. Three isolates, F, G and T were originally obtained from patients with acute amebic dysentery and another strain, C, was obtained from an asymptomatic carrier. All these strains were maintained for over two years in axenic culture. The isoenzyme pattern (zymodeme) of hexokinase (HK), phosphoglucomutase (PGM) and glucose phosphoisomerase (GPI) of these strains was found to belong to non-pathogenic group X, but the isoenzyme pattern of GPI resembled less pathogenic zymodeme XX and might be an intermediate type. Following inoculation of trophozoites into hamster livers and recovery after abscess formation, their isoenzyme pattern changed and revealed that they belonged to pathogenic type XIV. Liver passage caused an enhancement in amebic virulence as evidenced by their increased ability to destroy leukocytes. The results indicate that isoenzyme pattern is not a stable property of E. histolytica.

Absence of blue-yellow color vision loss among workers exposed to toluene or tetrachloroethylene, mostly at levels below occupational exposure limits

Possible color vision loss was examined with Lanthony's new color test and Ishihara's color vision test in 261 solvent workers and 120 controls (48 men and 72 women). The solvent workers were exposed to either predominantly toluene [46 ppm as geometric mean (GM); 63 men and 111 women], tetrachloroethylene alone (13 ppm; 30 men and 34 women), or a mixture (14 men and 9 women) of tetrachloroethylene (12 ppm) and trichloroethylene (7 ppm). The only instances of color vision loss that were detected in either the exposed workers or the controls were six cases of red-green loss (all in men). These six cases of red-green loss showed an unbiased distribution between the exposed workers and the nonexposed controls.

Human papillomavirus in benign and malignant ovarian and endometrial tissues

Ovarian and endometrial cancer tissues were examined for the presence of human papillomavirus (HPV) and the results were compared with the findings in normal tissues by polymerase chain reaction. Putative DNA of HPV types 16 and 18 that target DNA sequences from paraffin-embedded tissues were amplified with paired oligonucleotide primers that encode the E6 gene of HPV. The amplified DNA sequences were then detected with Southern blot hybridization analysis. The HPV DNA sequences were detected in both benign (50% ovarian, 70% endometrial) and malignant ovarian (27.2%) and endometrial (37.5%) tissue samples. Interestingly, eight hepatoma samples were also analyzed as tissue controls. The results were negative in seven, but positive in one with repeated tests. The results suggest that the spread of HPV in the upper genital tract may not be uncommon. The explanation of a positive liver tissue study result will have to await further study.

Formation of a toxic metabolite from gentamicin by a hepatic cytosolic fraction

We have demonstrated recently that incubation of the aminoglycoside gentamicin with an hepatic post-mitochondrial fraction produces a compound toxic to sensory cells from the inner ear in short-term culture; in contrast, the parent aminoglycoside was non-toxic in vitro (Huang MY and Schacht J, Biochem Pharmacol 40: R11-R14, 1990). In the present study, we investigated the subcellular distribution of the enzymatic activity and the nature of the metabolite. Isolated outer hair cells from the guinea pig cochlea were used to assay for cytotoxicity. The enzyme(s) responsible for this novel reaction of aminoglycosides was exclusively localized to the cytosolic fraction of guinea pig liver. No activity was detected in nuclear, lysosomal/mitochondrial or microsomal preparations. Furthermore, the toxin-forming enzymatic activity was associated with the high molecular weight fraction of the cytosol and did not require low molecular weight components. Filtration of the toxin through molecular weight cut-off membranes showed a molecular size of approximately 500. This evidence is consistent with the toxin being a gentamicin derivative.

Occupational dimethylformamide exposure. 2. Monomethylformamide excretion in urine after occupational dimethylformamide exposure

The relationship between the 8-h time-weighted average (TWA) intensity of exposure to N,N-dimethylformamide (DMF) vapor (with little possibility of skin contact with liquid DMF) and the subsequent excretion of N-monomethylformamide (MMF) precursor in shift-end urine samples was examined in 116 workers exposed to DMF and 92 workers exposed to DMF in combination with toluene. Urinary MMF level was examined also in 42 non-exposed subjects. The TWA vapor concentration in breathing zone air of each worker was successfully measured by means of a recently developed diffusive sampler in which water was used as an absorbent. The examination of gas chromatographic (GC) conditions for MMF determination showed that the formation of MMF was not saturated when the injection port temperature was set at 200 degrees C, reached a plateau at 250 degrees C, and showed no additional increase at 300 degrees C. There was a linear relationship between DMF in air and MMF in urine with a regression equation of y = 1.65 x + 1.69 (r = 0.723, P less than 0.01), where y is MMF (unit; mg/l, uncorrected for urine density) in urine and x is DMF (ppm) in air, when only those exposed to DMF were selected, and the injection port temperature was set at 250 degrees C. From this equation, it was possible to estimate that about 10% of the DMF absorbed will be excreted into urine as the MMF precursor. The slope of the regression line was significantly smaller among those exposed to DMF and toluene in combination as compared with those with DMF exposure only.

Occupational dimethylformamide exposure. 3. Health effects of dimethylformamide after occupational exposure at low concentrations

A factory survey was conducted in a plant where N,N-dimethylformamide (DMF) was in use during the production of polyurethane plastics and related materials. In all, 318 DMF-exposed workers (195 men and 123 women) and 143 non-exposed controls (67 men and 76 women) were examined for time-weighted average exposure (to DMF and other solvents by diffusive sampling), hematology, serum biochemistry, subjective symptoms, and clinical signs. Most of the exposed workers were exposed only to DMF, whereas others were exposed to a combination of DMF and toluene. DMF exposure in the former group was up to 7.0 ppm (geometric mean on a workshop basis), whereas it was up to 2.1 ppm in combination with 4.2 ppm toluene. Both hematology and serum biochemistry, results (including aspartate and alanine aminotransferases, gamma-glutamyl transpeptidase and amylase) were essentially comparable among the 3 groups. There was, however, a dose-dependent increase in subjective symptoms, especially during work, and in digestive system-related symptoms such as nausea and abdominal pain in the past 3-month period. The prevalence rate of alcohol intolerance complaints among male (assumedly) social drinkers was also elevated in relation to DMF dose.

Hepatitis B virus prevalence in industrialized cities in China

The prevalence of HBV infection was investigated by radioimmunoassay for HBsAg, anti-HBs and anti-HBc in over 1000 workers in large scale factories located in four industrial cities (Jinxi, Shanghai, Wuxi and Xian) in 1987 to 1990. The age dependency of the prevalence was not evident. The overall prevalence rate of those positive for any of the three markers was 62.6%. The rate was significantly (p < 0.01) higher than the rates found in Beijing in a previous study but lower than the values observed in earlier studies.

Drug-induced ototoxicity. Pathogenesis and prevention

Ototoxicity is a disabling adverse effect of several widely used classes of drugs, such as diuretics, anti-inflammatory agents, antineoplastic agents and aminoglycoside antibiotics. High-dose therapy with either diuretics or anti-inflammatory agents is primarily associated with acute and transient impairment of hearing or tinnitus. In contrast, long term treatment with antineoplastic agents or aminoglycoside antibiotics is typically associated with delayed and irreversible loss of hearing; lesion in the organ of Corti include the destruction of auditory sensory cells. Vestibular function can also be compromised by ototoxic drugs. Occasional cases of ototoxicity have been reported for a variety of other therapeutic compounds and environmental toxins. In addition, the simultaneous administration of multiple agents which are potentially ototoxic can lead to synergistic loss of hearing. Exposure to loud noise may also potentiate the hearing loss due to cochleotoxic drugs. Ototoxic agents can impair the sensory processing of sound at many cellular or subcellular sites. However, the molecular mechanisms of ototoxicity have not been established for most of these drugs, and structure-toxicity relationships have not been determined. It has therefore been difficult to predict the ototoxic potential of new drugs, and rational approaches to the prevention of ototoxicity are still lacking. The clinical and experimental features of ototoxicity are reviewed for several classes of drugs, with an emphasis on current knowledge of the mechanism and the possibilities for the prevention of ototoxicity for each.

Insulin suppresses hepatitis B surface antigen expression in human hepatoma cells

The human hepatoma Hep3B cells contain integrated hepatitis B viral genome and continually secret hepatitis B surface antigen (HBsAg). The production of HBsAg (but not alpha-fetoprotein) was suppressed by addition of low concentrations (0.1-1 nM) of insulin into serum-free medium. In addition, the suppression of HBsAg production by insulin was paralleled with the decrease in HBsAg mRNA abundance. Insulin also cause a rapid rate of disappearance of HBsAg mRNA (t 1/2, 2 h) in Hep3B cells. The Hep3B cells carry specific receptor with high affinity for insulin (Kd = 1.8 nM). The receptor showed an insulin-dependent protein tyrosine kinase activity. The half-maximal insulin concentration for the activation of the receptor kinase was about 5 nM. Only very high concentrations of insulin-like growth factor I and human proinsulin can compete for the insulin receptor binding and suppress HBsAg production, this suggests that insulin may act through its receptor binding to suppress HBsAg expression in human hepatoma Hep3B cells.

[Rectal examination for extent of perirectal infiltration in rectal carcinoma]

From 1983 to 1985, 214 patients with rectal carcinoma were assessed for the conformation rate of the rectal examination to the gross findings of the extent of perirectal infiltration in the resected specimens. It was found that the conventional classification of the extent of rectal infiltration by rectal examination, 1/4, 1/3, 2/4, 3/4 and 4/4 of the circumference, had only a conformation rate of 32.7% to the gross findings. According to the classification of 1/4 or less and more, the conformation rate could reach 93%. It was also found that the extent of perirectal infiltration, being closely related to the regional lymph node metastasis and the depth of invasion, was only demonstrated by this latter classification, which was not shown in the conventional classification. Hence, it is suggested that the rectal examination implying the extent of perirectal infiltration by simply classified into two groups: equal to or less than 1/4 and more than 1/4 of the circumference of the rectal wall.