Effect of acid and surfactant treatment on activated sludge dewatering and settling

The effect of pretreating activated sludge with sulfuric acid and surfactant on its exocellular polymer(ECP), dewaterability and settleability was investigated. It was observed that the centrifugal dewatering efficiency was increased with the decrease of sludge pH value, and which was further improved if the surfactant was simultaneously applied. However, to the filtration dewatering, the water content reached the minimum in the case of pH 2.5, and the additional use of surfactant was also favorable. The water content of sludge dewatered with filtration reached 73.99% when a pH 2.5 and a 0.1 g surfactant were employed, which was reduced by around 2% as compared with surfactant unused. Experimental results indicated that the sludge sedimentation rate was significantly accelerated under pH 2.5 condition, and which was increased once more by the utilization of surfactant. Further studies revealed that treating activated sludge with sulfuric acid at pH 2.5 or combined with surfactant was an effective method to remove the polymers from sludge surface and induced the decrease of ECP, which resulted in the improvement of dewaterability and settleability. This study suggested the potentiality of improving activated sludge mechanical dewaterability by the use of sulfuric acid to control its pH at 2.5 or together with a surfactant.

[Effect of anaerobic acidification treatment on nitrogen removal and toxicity reduction of coke plant wastewater]

Coke plant wastewater was treated by anaerobic acidification-anoxic-aerobic (A1-A2-O) biofilm process and anoxic-aerobic (A/O) biofilm process respectively. Toxicity reduction effects of the two processes were compared. The toxicity of coke plant wastewater was equal to that of mercury chloride with concentration of 0.19 mg/L. Its toxicity reduction was related to the removal of organic nitrogen. Anaerobic acidification unit acted an important role on removal of both organic nitrogen and reduction of toxicity of the wastewater. After treatment by A1-A2-O process, its toxicity can be decreased greatly. When HRT was 37.9 hours, The relative luminosity of the treated effluent to photobacterium can attain 96.8%, that is equal to the toxicity of mercury chloride with concentration of 0.023 mg/L.

One-year outcome of auditory-tactile-visual-vestibular intervention in the neonatal intensive care unit: effects of severe prematurity and central nervous system injury

Thirty-seven infants with severe central nervous system injury or extreme prematurity were randomly assigned to a multisensory (auditory-tactile-visual-vestibular) intervention or control group. Intervention began in the hospital at 33 weeks' postconceptional age and continued twice daily in the home until 2 months' corrected age. Mother-infant interactions during feedings were videotaped, and the Bayley Scales of Infant Development were administered. Control mothers stimulated their infants more during feeding, but these significant differences dissipated by 4 months. The presence of periventricular leukomalacia was associated with significantly poorer mental development, regardless of group assignment. Experimental infants tended to exhibit better motor and mental performance and had 23% fewer cerebral palsy diagnoses at 1 year, but these trends were not statistically significant. The type of brain injury was more important in determining 1-year developmental outcome than type of postnatal experience, suggesting that periventricular leukomalacia presents a major challenge for infant development.

Mechanism and kinetics of low-temperature thermochemical conversion process for sewage sludge

The low-temperature thermo-chemical conversion process for sewage sludge is a prospective technology, through which the energy in the sludge can be recovered. With the help of elementary analysis of sewage sludge and its conversion products, thermal gravimetric analysis (TGA) of the sludge and GC/MS analysis of the derived oil, a study was carried out on element transfer, characteristic conversion temperature and conversion reaction mechanism of the process. The following results are obtained: 1) the predominant conversion reactions are distillation of aliphatic compounds, splitting of protein peptide bonds and group transfer; and 2) the main components involved in the conversion are aliphatic compounds and protein, with the lower reaction temperature for the former, the higher for the latter and the highest for saccharides. Based on the mechanism analyses, the simplified reaction model of the thermo-chemical conversion process for sewage sludge consists of two serial competitive reactions (producing volatile matter and char respectively). The estimated Arrhennius kinetic parameters of the reaction model based on TGA testing resultsare A1 = 4.15 x 10(6) 1/s, n1 = 2, E1 = 98 kJ/mol; A2 = 1.42 x 10(5) 1/s, n2 = 2, E2 = 85 kJ/mol; A3 = 1.01 x 10(12) 1/s, n3 = 4, E3 = 190 kJ/mol; A4 = 1.33 x 10(9) 1/s, n4 = 4, E4 = 146 kJ/mol.

Reclaimed municipal wastewater--a potential water resource in China

Due to water resource shortage and socio-economic development within twenty years, China faces serious problems of water supply and water pollution. Several criteria and suitable reclamation processes related to water reuse have been created in China, which are helpful to improve the situation of water scarcity. In the future, reclaimed municipal wastewater reuse will mainly be developed for urban and industrial use. Potential supply quantity of reclaimed water, quality of reclaimed water, and reclamation cost are favorable to potential reuses. Based on further public environmental education, on a relevant development of national and local standards for reclaimed water quality, and on an increase of sanitary rate, more and more planned reclaimed water reuse projects would be expected in China.

[Study of the correlation between in vitro and in vivo evaluation methods on biomaterials--DNA test and muscular implant test]

With the wide-spread use of biomaterials, the safety evaluation on biomaterials has become a very important step. This study on the correlation between DNA test and muscular implant test was done for finding out good in vitro evaluation method. The tissue toxicities of seven biomaterials were examined. Good correlation between DNA test and muscular implant test was demonstrated by Spearman sequential correlation analysis.

[Cytocompatible evaluation for skin reproducing membrane of medical fibroin]

This study was intended to evaluate the cytocompatibility of skin reproducing membrane of medical fibroin. Cell growth rate test and hemolysis test were conducted to investigate the cytotoxicity and hemolysis reaction for skin reproducing membrane. The results showed there was no obvious cytotoxicity for this kind of membrance. The hemolysis rate was 1.15%. In conclusion, skin reproducing membrane is a material of good cytocompatibility.

Evidence for an energy scale for quasiparticle dispersion in Bi2Sr2CaCu2O8

Quasiparticle dispersion in Bi2Sr2CaCu2O8 is investigated with improved angular resolution as a function of temperature and doping. Unlike the linear dispersion predicted by the band calculation, the data show a sharp break in dispersion at 50+/-15 meV binding energy where the velocity changes by a factor of 2 or more. This change provides an energy scale in the quasiparticle self-energy. This break in dispersion is evident at and away from the d-wave node line, but the magnitude of the dispersion change decreases with temperature and with increasing doping.

Hyoid position, pharyngeal airway and head posture in relation to relapse after the mandibular setback in skeletal Class III

This study evaluates the process of relapse after mandibular setback surgery by an analysis of the role of craniofacial morphology, hyoid position, pharyngeal airway and head posture. Subjects examined were 62 patients who received the sagittal split ramus osteotomies (SSRO). Changes of the craniofacial and related structures were evaluated from the serial cephalograms up to 3 years after the surgery. Results indicated that mandibular relapse represented by Pg occurred mostly within 6 months after the surgery. A net setback of the mandible was 9.1 mm and the superior move was 1.7 mm, with a reduction of 7.2 mm in mandibular length, 4.2 mm in ramus height, 3.7 mm in posterior face height, 2.6 degrees in gonial angle, an increase of 2.9 degrees in mandibular plane angle (MPA) by the last examination. Hyoid bone moved backward and downward and head posture was raised. The forward relapse of Pg was correlated with the changes of ANB, MPA, ramus height and hyoid position. Only hyoid position was predictably correlated with mandibular morphology and head posture. These findings suggest that mandibular setback alters the relationship among the hyoid position, pharyngeal airway and the head posture. It might be critical, therefore, relapse is closely monitored and controlled before the full healing of fragments and new muscular balance is established.

Hyoid position, pharyngeal airway and head posture in relation to relapse after the mandibular setback in skeletal Class III

This study evaluates the process of relapse after mandibular setback surgery by an analysis of the role of craniofacial morphology, hyoid position, pharyngeal airway and head posture. Subjects examined were 62 patients who received the sagittal split ramus osteotomies (SSRO). Changes of the craniofacial and related structures were evaluated from the serial cephalograms up to 3 years after the surgery. Results indicated that mandibular relapse represented by Pg occurred mostly within 6 months after the surgery. A net setback of the mandible was 9.1 mm and the superior move was 1.7 mm, with a reduction of 7.2 mm in mandibular length, 4.2 mm in ramus height, 3.7 mm in posterior face height, 2.6 degrees in gonial angle, an increase of 2.9 degrees in mandibular plane angle (MPA) by the last examination. Hyoid bone moved backward and downward and head posture was raised. The forward relapse of Pg was correlated with the changes of ANB, MPA, ramus height and hyoid position. Only hyoid position was predictably correlated with mandibular morphology and head posture. These findings suggest that mandibular setback alters the relationship among the hyoid position, pharyngeal airway and the head posture. It might be critical, therefore, relapse is closely monitored and controlled before the full healing of fragments and new muscular balance is established.

A fast, sensitive and specific method for rice dwarf virus detection by northern blot hybridization

Based on stability of double-stranded (ds) RNA, a new, fast, sensitive, and specific method for detection of genomic rice dwarf virus (RDV) dsRNA by molecular hybridization was developed. In contrary to the commonly used, standard Northern blot analysis, dsRNA is denatured in the immobilized state on the blot. Therefore, risk of degradation of single-stranded (ss) RNA by ribonuclease (RNase) during sample preparation, electrophoresis and blotting is eliminated. This method overcomes disadvantage of incomplete denaturation of dsRNA in Northern blot analysis. In conclusion, the newly developed method is reliable, sensitive, very specific, and gives a low background. The entire procedure is also less time consuming; it can be completed within 2-3 days. The new method may be regarded as a modification of the standard Northern blot analysis.

[EB virus infection and expression of P53 and P16 in non-Hodgkin's lymphoma]

OBJECTIVE

To observe the presence of Epstin-Barr virus (EBV) and expression of P53 and P16 in the non-Hodgkin's lymphoma (NHL) occurring in the nasal cavity and pharyngeal Waldeyer's ring.

METHODS

In situ hybridization was used to detect EBV-DNA and P16-mRNA and immunohistochemical staining was used to examine the expression of LMP1, P53 and P16 in the 36 cases. Five cases whose EBV-DNA were negative at first assay by hybridization was re-detected for EBV-DNA by PCR.

RESULTS

Positive expression rates of EBV-DNA, LMP1, P16 mRNA, P53 and P16 were 63.9%, 27.8%, 30.6%, 19.4% and 22.2%. P53 and P16 expressions were not significantly different between T cell NHL and B cell NHL, nor were them significantly different between EBV positive and negative cases.

CONCLUSION

A higher percentage of EBV infection was detected in the nasal cavity and pharyngeal Waldeyer's ring in NHL. EBV infection was not significantly associated with P53 and P16 expresions in NHL.

Effect of appliance reactivation after decay of initial activation on osteoclasts, tooth movement, and root resorption

Clinical orthodontists frequently reactivate appliances following decay. Studies of tooth movement and tissue responses following reactivations indicate that linear tooth movement and rapid recruitment of osteoclasts can be achieved if reactivation is timed to coincide with the latter part of the bone remodeling cycle initiated by the first activation. Both can be delayed if reactivations are timed for the early part of the previous cycle. The objective of this study was to examine tooth movement, root resorption, and osteoclast recruitment following appliance reactivation after the first activation had decayed. Bilateral orthodontic appliances were activated with 40 cN in 144 rats to mesially tip the maxillary molars. After 16 days, rats were randomized into two groups of 72. In group 1, appliances were reactivated in precisely the same manner as the first activation. In group 2, appliances were sham-reactivated. Rats were sacrificed at 1, 3, 5, 7, 10, and 14 days. Orthodontic movement was measured cephalometrically; changes in osteoclasts and root resorption were assessed at both compression and tension sites histomorphometrically; tartrate-resistant acid phosphatase (TRAP) was measured in alveolar bone and serum biochemically. Orthodontic tooth movement was linear in group 1, but osteoclasts required 3 to 5 days to appear. There were no group- or time-related differences in root resorption. Bone TRAP levels were elevated in both groups but dropped significantly (p<0.01) in group 2 at day 7. Appliance reactivations that followed decay of the first activation produced efficient tooth movement without increased risk of root resorption, but these changes were not accompanied by rapid osteoclast recruitment at compression sites. Timing appliance reactivations for the latter portion of the previous bone remodeling cycle could have significant clinical advantages because the delay period seen in tooth movement following a single activation or short-term reactivation can be avoided.

[Study on correlation between in vivo and in vitro tests of biomaterials--correlation between leukocyte chemotaxis test and muscular implant test in rabbits]

The purpose of this study was to investigate the correlation between the results of in vivo and in vitro tests of biomaterials. With muscular implant test and leukocyte chemotaxis test, the levels of tissue toxicity of seven biomaterials were evaluated. The samples with high-level toxicity showed weak leukocyte chemotaxis, which would influence the anti-inflammatory reaction to foreign bodies. By the method of Spearman rank correlation, the coefficient was between 0.89286-0.98198 indicating that the correlation of the two tests is excellent.

Molecular cloning and characterization of two putative G protein-coupled receptors which are highly expressed in the central nervous system

We have cloned from a rat hypothalamic cDNA library two closely related G protein-coupled receptors (GPCRs) which we have designated GPCR/CNS1 and GPCR/CNS2. The peptide sequences of these two G protein-coupled receptors shared 42% identity with each other and were next most closely related to the endothelin receptors and the bombesin-like peptide receptors (approximately 25% identity). Northern blot analysis showed that both GPCR/CNS1 and GPCR/CNS2 were very highly expressed in rat brain. In situ hybridization of rat brain demonstrated broad distribution of both receptors throughout the central nervous system. GPCR/CNS1 appeared to be expressed primarily in glial cells of the fiber tracts, while GPCR/CNS2 was expressed primarily in cells of the gray matter. The different distribution patterns of these two receptors in rat brain suggests distinct functional roles for each receptor in the central nervous system. Expression of these two receptors in Xenopus oocytes showed no response to any known endothelin and bombesin-like peptides. Therefore, the endogenous ligands and physiological significance of GPCR/CNS1 and GPCR/CNS2 remain to be elucidated, but may be related to the endothelins or bombesins. The very abundant expression in brain by these two receptors, however, suggests that they play important roles in the central nervous system.

Hormonal regulation of glutamate receptor gene expression in the anteroventral periventricular nucleus of the hypothalamus

Glutamate plays an important role in mediating the positive feedback effects of ovarian steroids on gonadotropin secretion, and the preoptic region of the hypothalamus is a likely site of action of glutamate. The anteroventral periventricular nucleus (AVPV) of the preoptic region is an essential part of neural pathways mediating hormonal feedback on gonadotropin secretion, and it appears to provide direct inputs to gonadotropin releasing hormone (GnRH)-containing neurons. Immunohistochemistry and in situ hybridization were used in this study to define the distribution and hormonal regulation of glutamate receptor subtypes in the AVPV of juvenile female rats. Neurons that express the NMDAR1 receptor subtype are abundant in the AVPV, as are cells that express AMPA receptor subtypes (GluR1, GluR2, and GluR3 but not GluR4), and the AVPV appears to contain a dense plexus of NMDAR1-immunoreactive presynaptic terminals. However, AVPV neurons do not seem to express detectable levels of kainate receptor (GluR5, GluR6, and GluR7) or metabotropic receptor (mGluR1-6) subtypes. Treatment of ovariectomized juvenile rats with estradiol induced expression of GluR1 mRNA but did not alter levels of GluR2 or GluR3 mRNA. Treatment of estrogen-primed ovariectomized juvenile rats with progesterone caused an initial increase in GluR1 mRNA expression, followed by a small decrease 24 hr after treatment. In contrast, estrogen appears to suppress levels of NMDAR1 mRNA in the AVPV, which remained unchanged after progesterone treatment. Thus, one mechanism whereby ovarian steroids may provide positive feedback to GnRH neurons is by altering the sensitivity of AVPV neurons to glutamatergic activation.

[A clinical study of bacterial infection in patients with chronic obstructive pulmonary disease]

OBJECTIVE

To investigate the association of bacteriologic characteristics and bacterial infection in small airway disease.

METHODS

Fiberoptic bronchoscopy and ultrathin fiberoptic bronchoscopy were performed on outpatients with COPD and chronic bronchitis both during stable stage and acute exacerbation. Samples were obtained from both large and small airways by protective specimen brush, and bacteria were cultured quantitatively.

RESULTS

The positive rates for pathogens in patients with COPD and chronic bronchitis during acute exacerbation were 26.6% (8/30) and 23.5% (5/17) respectively. Major pathogens in acute COPD include Staphylococcus aureus, Streptococcus pneumoniae, Hemophilus influenzae, Moraxella catarrhalis, and Pseudomonas aeruginosa. All of the pathogens were present in large airways, with 2 strains present in small airways concurrently. The positive rates for pathogens in stable COPD and chronic bronchitis were 24.0% (6/24) and 11.7% (2/17) respectively. Major pathogens found in stable COPD include Staphylococcus epidermis, Micrococcus and Streptococcus pneumoniae. The bacteria were less than 10 x 10(3) cfu/ml, present mainly in large airways. There was no significant difference in the extent of small airway diseases between COPD with bacterial infection and that without bacterial infection (P > 0.05).

CONCLUSIONS

Bacterial infection is not a major pathogenic factor in stable COPD. There is no direct cause-and-effect relationship between bacterial infection and the extent of small airway diseases in patients with COPD.

[Functional improvement of remnant stomach after proximal subtotal gastrectomy for cardiac cancer]

OBJECTIVE

To evaluate the function of the remnant stomach after proximal subtotal gastrectomy for cardiac cancer and to improve the life quality of post-surgical patients.

METHODS

17 patients with cardiac cancer underwent proximal subtotal gastrectomy combined with disconnection of pyloric sphincter (PSG + DPS) by finger pressing. Intraoperative pyloric manometric studies were performed in the 17 patients before and after DPS. Five subjects who underwent laparotomy for non-esophagogastric reasons was taken as controls. Total bile acids (TBA) in gastric juice was tested in the 17 patients at 5th postoperative day, and radionuclide gastric emptying was also studied from the 18th to 20st postoperative day.

RESULTS

Both pyloric resting pressure and pyloric contracting pressure were significantly decreased after DPS (P > 0.01). In comparison with normal subjects, PCP was increased before DPS (P > 0.01) and decreased after the procedure (P < 0.05). However, PRP did not show significant differences before (P > 0.05) and after (P > 0.05) DPS. There were no significant differences regarding TBA content in gastric juice in PSG + DPS group, PSG group, and normal subjects (P > 0.05). The time required for the stomach to empty half of its radioactive contents (T1/2) was longer in the patients having PSG only than those undergoing PSG + DPS (P < 0.01) and normal controls (P < 0.05). However, there were no significant differences regarding T1/2 between the patients with PSG + DPS and normal controls (P > 0.05).

CONCLUSIONS

The emptying of remnant stomach after subtotal gastrectomy for cardiac cancer is delayed because of the increase of emptying-resistance and decrease of peristalsis. PSG combined with DPS not only improves gastric emptying, but also prevents duodenogastric reflux. Consequently, postoperative life quality of the patients with cardiac cancer can be effectively improved.

[ICAM-1 and HLA-DR expression in bronchial epithelial cells from patients with chronic obstructive pulmonary disease]

OBJECTIVE

To study the expression of adhesion molecules in epithelial cells from patients with COPD.

METHOD

The expression of ICAM-1 and HLA-DR in airway epithelial cells from 10 COPD patients, 7 asthmatic patients, 9 chronic bronchitis patients, and 10 healthy volunteers was evaluated using immunohistochemistry techniques. The cells were stained and analysed microscopically.

RESULT

The percentage of neutrophils in brushing cells from COPD(0.04) were significantly higher than those from asthma(0.01) and normal subjects (0.01). More goblet cells were found in COPD (mean 0.13) and chronic bronchitis (mean 0.11) as compared with asthma (0.03) and healthy volunteers. As to the expression of ICAM-1 in COPD, the percentage of cells expressing ICAM-1(15%) significantly increased in comparison with chronic bronchitis (6.28% P < 0.05), healthy volunteer(1.8%, P < 0.05), and asthma (8.8%, P > 0.05). The score of expression of ICAM-1 in COPD was significantly higher than those in asthma (P < 0.05), chronic bronchitis (P < 0.05) and normal subjects (P < 0.001). As to the expression of HLA-DR in COPD, the percentage of cells expressing HLA-DR(5.9%) significantly increased in comparison with normal subjects (0.6% P < 0.05), but there was no significant difference among COPD, asthma and chronic bronchitis. The score of expression of HLA-DR in COPD was significantly higher than those in healthy volunteers (P < 0.001), chronic bronchitis (P < 0.001) and asthma (P < 0.05). In addition, the percentage of neutrophils in brushing cells from COPD significantly correlated with the expression of ICAM-1 (r = 0.81, P < 0.01).

CONCLUSION

Upregulation of ICAM-1 in epithelial cell from COPD correlates with the neutrophil infiltration in COPD. Lymphocytes are in an active state in COPD and the use of brush biopsies of the bronchial epithelium may serve as a diagnostic tool for differentiation among COPD, chronic bronchitis and asthma.

Development of a sexually dimorphic projection from the bed nuclei of the stria terminalis to the anteroventral periventricular nucleus in the rat

The principal nucleus of the bed nuclei of the stria terminalis (BSTp) is larger in male rats and conveys olfactory information relevant for reproduction to the hypothalamus. In males, the BSTp provides a massive projection to the anteroventral periventricular nucleus of the preoptic region (AVPV), which in contrast to most sexually dimorphic nuclei contains more neurons in female rats. Injections of the anterograde tracer Phaseolus vulgaris leucoagglutinin into the BSTp of adult female rats failed to demonstrate the strong projection to the AVPV observed previously in males. The ontogeny of this robust sex difference was examined by using the axonal marker DiI. The projection from the BSTp to the AVPV is established between postnatal day 9 (P9) and P10 in male rats and seems to be maintained during the juvenile period. Although labeled fibers extended from the BSTp toward the preoptic region in both male and female neonates, a similar connection with the AVPV was not apparent in female rats at any of the ages studied, and the density of labeled axons in the AVPV of P10 males was 20-fold greater than that of P10 females. A projection from the BSTp to the medial preoptic nucleus was also weaker in females but was much more substantial than that to the AVPV. These findings suggest that a sex- and region-specific activity influences the development of the projection from the BSTp to the AVPV, producing a sexually dimorphic architecture in pathways that convey olfactory information to the hypothalamus.

High-external-quantum-efficiency organic light-emitting devices

We study the internal and external quantum efficiencies of vacuum-deposited organic light-emitting devices (OLED's). The internal quantum efficiency of OLED's based on tris-(8-hydroxyquinoline) aluminum is calculated to be 5.7 times the observed external quantum efficiency ?(e), consistent with measurements. We demonstrate a shaped substrate that increases ?(e) by a factor of 1.9+/-0.2 over similar OLED's fabricated upon flat glass substrates and leads to a 100%-emissive aperture, i.e., the emitting area completely occupies the display area even in the presence of metal interconnects. We also discuss a substrate structure that increases ?(e) by an additional factor of 2. The high device efficiencies are promising for developing OLED-based displays with extremely low power consumption and increased operational lifetime.

Vacuum-deposited, nonpolymeric flexible organic light-emitting devices

We demonstrate mechanically flexible, organic light-emitting devices (OLED's) based on the nonpolymetric thin-film materials tris-(8-hydroxyquinoline) aluminum (Alq(3)) and N, N(?) -diphenyl- N, N(?) -bis(3-methylphenyl)1- 1(?) biphenyl-4, 4(?) diamine (TPD). The single heterostructure is vacuum deposited upon a transparent, lightweight, thin plastic substrate precoated with a transparent, conducting indium tin oxide thin film. The flexible OLED performance is comparable with that of conventional OLED's deposited upon glass substrates and does not deteriorate after repeated bending. The large-area (~1 - cm>(2)) devices can be bent without failure even after a permanent fold occurs if they are on the convex substrate surface or over a bend radius of ~0.5>cm if they are on the concave surface. Such devices are useful for ultralightweight, flexible, and comfortable full-color flat panel displays.

Neuropathology of degenerative cell death in Caenorhabditis elegans

In Caenorhabditis elegans necrosis-like neuronal death is induced by gain-of-function (gf) mutations in two genes, mec-4 and deg-1, that encode proteins similar to subunits of the vertebrate amiloride-sensitive epithelial Na+ channel. We have determined the progress of cellular pathology in dying neurons via light and electron microscopy. The first detectable abnormality is an infolding of the plasma membrane and the production of small electron-dense whorls. Later, cytoplasmic vacuoles and larger membranous whorls form, and the cell swells. More slowly, chromatin aggregates and the nucleus invaginates. Mitochondria and Golgi are not dramatically affected until the final stages of cell death when organelles, and sometimes the cells themselves, lyse. Certain cells, including some muscle cells in deg-1 animals, express the abnormal gene products and display a few membrane abnormalities but do not die. These cells either express the mutant genes at lower levels, lack other proteins needed to form inappropriately functioning channels, or are better able to compensate for the toxic effects of the channels. Overall, the ultrastructural changes in these deaths suggest that enhanced membrane cycling precedes vacuolation and cell swelling. The pathology of mec-4(gf) and deg-1(gf) cells shares features with that of genetic disorders with alterations in channel subunits, such as hypokalemic periodic paralysis in humans and the weaver mouse, and with degenerative conditions, e.g., acute excitotoxic death. The initial pathology in all of these conditions may reflect attempts by affected cells to compensate for abnormal membrane proteins or functions.

Genetic interactions affecting touch sensitivity in Caenorhabditis elegans

At least 13 genes (mec-1, mec-2, mec-4-10, mec-12, mec-14, mec-15, and mec-18) are needed for the response to gentle touch by 6 touch receptor neurons in the nematode Caenorhabditis elegans. Several, otherwise recessive alleles of some of these genes act as dominant enhancer mutations of temperature-sensitive alleles of mec-4, mec-5, mec-6, mec-12, and mec-15. Screens for additional dominant enhancers of mec-4 and mec-5 yielded mutations in previously known genes. In addition, some mec-7 alleles showed allele-specific, dominant suppression of the mec-15 touch-insensitive (Mec) phenotype. The dominant enhancement and suppression exhibited by these mutations suggest that the products of several touch genes interact. These results are consistent with a model, supported by the known sequences of these genes, that almost all of the touch function genes contribute to the mechanosensory apparatus.

Hormonal regulation of CREB phosphorylation in the anteroventral periventricular nucleus

The anteroventral periventricular nucleus (AVPV) is a nodal point in neural circuits regulating secretion of gonadotropin and contains sexually dimorphic populations of hormonally regulated dopamine-, dynorphin-, and enkephalin-containing neurons. Because the tyrosine hydroxylase (TH), prodynorphin (PDYN), and proenkephalin (PENK) genes contain cAMP response elements that control their expression in their promoters, we used histochemical methods to determine whether ovarian steroids alter expression of the cAMP response element-binding protein (CREB) in the AVPV. Because the ability of CREB to activate transcription depends on phosphorylation at Ser133, we also evaluated the effects of acute steroid treatment on levels of phosphorylated CREB (pCREB) in AVPV neurons by using an antibody that differentiates between CREB and pCREB. Treatment of ovariectomized rats with estradiol treatments caused a significant induction in the number of pCREB-immunoreactive nuclei within 30 min that was maintained for at least 4 hr, but did not alter CREB immunostaining in the AVPV. Pretreatment with the estrogen antagonist Nafoxidine blocked this induction. In contrast, acute administration of progesterone to estrogen-primed animals suppressed and then increased pCREB staining in the ASVPV at 30 and 60 min, respectively; no significant differences between experimental and control animals were apparent by 2 hr after progesterone treatment. Double-labeling experiments showed that pCREB was colocalized with PDYN, PENK, or TH mRNA in the AVPV, suggesting that pCREB may mediate the effect of steroid hormones on gene expression in these neurons.

[Heel pain and calcaneal spurs]

The authors of this paper have reviewed 137 X-ray films of the involved feet and followed up 30 patients all of them suffering from heel pain treated in the authors' hospital during 1980-1985, in order to find out the relationship between the length, shape and the direction of the spurs with the heel pain. We have found: (1) There are no clear relationship between heel pain and the length, shape and the direction of the calcaneal spur. (2) The plantar soft tissue of the painful foot was thickened, indicating the heel pain was due to inflammation in the plantar soft tissue. (3) Heel pain is related to the patient's age and sex. (4) The spurs still exist and grow even bigger after the syndrome disappears.

[Expression and significance of hepatitis B virus genes in human primary intrahepatic cholangiocarcinoma and its surrounding tissue]

In order to explore the significance of HBV in the pathogenesis of cholangiocarcinoma at molecular level, HBV DNA, X gene, pre-S gene, S gene and C gene in 40 cases of primary intrahepatic cholangiocarcinoma and its surrounding tissue were detected by in situ hybridization technique. The results showed that 33 cases (82.5%) were positive for HBV DNA, while 31 (77.5%), 26 (65.0%), 24 (60.0%) and 27 (67.5%) cases were positive for X gene, pre-S gene, S gene and C gene, respectively. The results of this study suggest that there exists a close relationship between human primary intrahepatic cholangiocarcinoma and HBV chronic persistent infection. The expression of X gene might play an important role in the pathogenesis of the primary intrahepatic cholangiocarcinoma.

Preparation and separation of hydroxy derivatives of uroporphyrinogen I by high-performance liquid chromatography with electrochemical detection

The preparation and high-performance liquid chromatography (HPLC) separation of meso-hydroxyuroporphyrinogen I, hydroxyacetic acid uroporphyrinogen I and beta-hydroxypropionic acid uroporphyrinogen I is described. meso-Hydroxyuroporphyrin I, hydroxyacetic acid uroporphyrin I and beta-hydroxypropionic acid uroporphyrin I were isolated from the urine of a patient with congenital erythropoietic porphyria. The porphyrins were reduced to the corresponding porphyrinogens with 3% (w/w) Na/Hg amalgam. The hydroxy porphyrinogens were separated on a Hypersil ODS column with 4% (v/v) acetonitrile in 1 M ammonium acetate buffer, pH 5.16, containing EDTA (0.27 mM) as the mobile phase, and detected electrochemically. Reduction of meso-hydroxyuroporphyrin I and hydroxyacetic acid uroporphyrin I, followed by HPLC analysis, showed that, in addition to the expected formation of meso-hydroxyuroporphyrinogen I and hydroxyacetic uroporphyrinogen I, respectively, uroporphyrinogen I was also produced. Reduction of beta-hydroxypropionic acid uroporphyrin I, however, gave beta-hydroxypropionic acid uroporphyrinogen I, acrylic acid uroporphyrinogen I and uroporphyrinogen I as the products. The peaks were identified by conversion into the porphyrin methyl esters and analysed by liquid secondary-ion mass spectrometry.

Extracellular proteins needed for C. elegans mechanosensation

The mec-5 and mec-9 genes encode putative extracellular proteins that allow a set of six touch receptor neurons in C. elegans to respond to gentle touch. MEC-5 is a collagen made by the epidermal cells that surround the touch cells. Mutations causing touch insensitivity affect the Gly-X-Y repeats of this collagen. mec-9 produces two transcripts, the larger of which is expressed in the touch cells and two PVD neurons. This transcript encodes a protein with 5 Kunitz-type protease inhibitor domains, 6 EGF-like repeats (2 of the Ca(2+)-binding type), and a glutamic acid-rich region. Missense mutations causing touch insensitivity affect both the EGF-like and Kunitz domains. Since mec-9 loss of function mutations dominantly enhance the touch insensitive phenotype of several mec-5 mutations, MEC-5 and MEC-9 may interact. We propose that these proteins provide an extracellular attachment point for the mechanosensory channels of the touch cells.

A stomatin-like protein necessary for mechanosensation in C. elegans

The mec-2 gene is required for the function of a set of six touch receptor neurons in the nematode Caenorhabditis elegans; mec-2 mutants, which are touch-insensitive, have touch cells that appear morphologically normal. Gene interaction studies suggest that mec-2 positively regulates the activity of the putative mechanosensory transduction channel (and the present paper), comprised in part of proteins encoded by the two degenerin genes mec-4 and mec-10 The central region of the mec-2 protein (MEC-2) is very similar to stomatin, an integral membrane protein (band 7.2b) in human red blood cells that is thought to regulate cation conductance. MEC-2-LacZ fusions are distributed along the touch receptor axons. This axonal distribution, which is mediated by the mec-2-specific amino terminus, is disrupted by mutations in mec-12, an alpha-tubulin gene needed for touch cell function. Our results indicate that MEC-2 links the mechanosensory channel and the microtubule cytoskeleton of the touch receptor neurons. Such linkage provides the basis for a mechanism of mechanosensation whereby microtubule displacement leads to channel opening.

[The use of the Ho: YAG laser in arthroscopic surgery]

From May 1993 to April 1994 we had performed 72 cases (total 84 joints) of arthroscopic operations with holmium laser. It included 12 bilateral knees, and single joints in the shoulder, elbow, wrist and ankle. We performed partial menisectomy, chondroplasy, partial synovectomy and lateral retinacular release. The energy used was from 1 to 12kJ depending the complexity of the operations. All these cases had been followed up 6 to 16 months. The function of the joints was good, only two cases had joint effusion. The rate of good and excellent results was 97%.

Hormonal regulation of opioid peptide neurons in the anteroventral periventricular nucleus

Steroid hormones provide a means of coordinating the activity of widespread neural systems that mediate endocrine, autonomic, and somatomotor aspects of reproductive processes that are essential for the propagation of mammalian species. Because these processes are quite different in each sex, the neural pathways that control them are also sexually differentiated. The anteroventral periventricular nucleus (AVPV) of the preoptic region occupies a nodal point in sexually dimorphic forebrain circuits and appears to play a critical role in regulating gonadotropin secretion. The AVPV contains sexually dimorphic populations of opioid peptide containing neurons that display different patterns of development and are differentially regulated in adult animals by gonadal steroids. Moreover, estrogen (ER) and progesterone (PR) receptors are expressed in AVPV neurons in a transmitter-specific way, and the expression of these nuclear transacting factors is differentially regulated by sex steroids. Thus, neurons in the AVPV show distinct patterns of hormonal regulation of gene expression, and distinct hormone receptor profiles.

Idiopathic CD4+ T-lymphocytopenia--immunodeficiency without evidence of HIV infection

BACKGROUND

The human immunodeficiency virus (HIV), the etiologic agent of the acquired immunodeficiency syndrome (AIDS), infects and depletes CD4+ T lymphocytes. Recently, patients have been described with profound CD4+ T-lymphocytopenia but without evident HIV infection, a condition now termed idiopathic CD4+ T-lymphocytopenia, and a national surveillance network has been set up to investigate such cases.

METHODS

We studied 12 patients with CD4+ T-lymphocytopenia who were referred to us from three U.S. cities. Blood samples were tested for HIV with specific antibody assays, viral cultures, and polymerase-chain-reaction (PCR) techniques.

RESULTS

The patients (10 men and 2 women) ranged in age from 30 to 69 years. Eight had risk factors for HIV infection. The clinical manifestations were heterogeneous: five patients had opportunistic infections, five had syndromes of unknown cause, and two had no symptoms. Two patients died from acute complications of their immunodeficiency. The patients' lowest CD4+ lymphocyte counts ranged from 3 to 308 per cubic millimeter (mean, 149). Three patients had complete or partial spontaneous reversal of the CD4+ T-lymphocytopenia. Concomitant CD8+ T-lymphocytopenia was noted in three patients, and abnormal immunoglobulin levels were found in five. Multiple virologic studies by serologic testing, culture, and PCR were completely negative for HIV in all patients.

CONCLUSIONS

Our 12 patients with idiopathic CD4+ T-lymphocytopenia appear to be epidemiologically, clinically, and immunologically heterogeneous. It is unclear whether this syndrome is new, transmissible, or acquired. Many of the clinical and immunologic features are distinct from those found in AIDS, and our extensive virologic studies found no evidence of HIV infection. The cause of this condition remains unknown.