An elderly female who survived more than 30 years following a diagnosis of Takayasu's arteritis, complicated by fatal intestinal amyloidosis

Compared to young patients with Takayasu's arteritis (TA), little information about elderly patients with TA has been reported. Additionally, no reports were found regarding TA cases with complications of intestinal amyloidosis. This is a case report of an elderly female, who developed intestinal amyloidosis, during late-stage TA. After years of outpatient management, she developed sudden severe dyspnea with pulmonary effusion, requiring hospitalization. After this event, betamethasone was replaced by methotrexate (MTX) for the next 34 months, but it seemed ineffective. After 1.5 years, she developed intractable diarrhea, followed by increases in BUN and serum creatinine (Cr), requiring several courses of hemodialysis. Colonoscopy revealed the presence of amyloid in her intestine, although she died of complicated sepsis caused by MRSA infection. This may be the first paper describing intestinal amyloidosis in a TA patient. Additionally, her case is rare in that she lived more than 30 years after the onset and diagnosis of TA.

Preparation and evaluation of a hyaluronate-collagen film for preventing post-surgical adhesion

Post-surgical adhesion occurs when fibrous strands of scar tissue form, leading to the abnormal joining of anatomical structures. Patients undergoing abdominal surgery are at risk of the complications associated with intraperitoneal adhesions. Hyaluronic acid (HA) is a biocompatible, biodegradable and non-toxic natural polymer, which is gaining popularity as a barrier agent for preventing post-surgical adhesions. As HA is water-soluble and rapidly degraded in vivo, chemical modification is required to produce a non-soluble sheet that might be used to prevent tissue adhesion. We developed a range of biocompatible cross-linked HA-collagen composites and then evaluated them in a rat model of post-surgical adhesion. The results showed that cross-linked HA-collagen was almost totally resistant to hyaluronidase digestion. HA-collagen membranes induced minimal tissue reactions and were bioresorbed within 14 days post-surgery. These results suggest that cross-linked HA-collagen membrane may be a valuable anti-adhesion material to prevent post-surgical intraperitoneal adhesion.

Low energy electron irradiation induced deep level defects in 6H-SiC: the implication for the microstructure of the deep levels E1/E2

N-type 6H-SiC samples irradiated with electrons having energies of E(e)=0.2, 0.3, 0.5, and 1.7 were studied by deep level transient technique. No deep level was detected at below 0.2 MeV irradiation energy while for E(e)>/=0.3 MeV, deep levels ED1, E(1)/E(2), and E(i) appeared. By considering the minimum energy required to displace the C atom or the Si atom in the SiC lattice, it is concluded that generation of the deep levels E(1)/E(2), as well as ED1 and E(i), involves the displacement of the C atom in the SiC lattice.

Observation of microwave-induced zero-conductance state in Corbino rings of a two-dimensional electron system

Using Corbino samples we have observed oscillatory dc conductance in a high-mobility two-dimensional electron system when it is subjected to crossed microwave and magnetic fields. At the strongest of the oscillation minima the conductance is found to be vanishingly small, indicating a macroscopic insulating state associated with this minimum. With increasing voltage bias, a crossover from Ohmic to electron-heating regime is observed.

Zener tunneling between landau orbits in a high-mobility two-dimensional electron gas

Magnetotransport in a laterally confined two-dimensional electron gas (2DEG) can exhibit modified scattering channels owing to a tilted Hall potential. Transitions of electrons between Landau levels with shifted guiding centers can be accomplished through a Zener tunneling mechanism, and make a significant contribution to the magnetoresistance. A remarkable oscillation effect in weak field magnetoresistance has been observed in high-mobility 2DEGs in GaAs -Al Ga 0.3As (0.7) heterostructures, and can be well explained by the Zener mechanism.

[Analysis of CD8(+) and CD8(+)CD28(-) cell subsets in patients with hepatocellular carcinoma]

OBJECTIVE

To study the expression of the costimulatory molecule CD28 on peripheral blood CD8(+)T cells from patients with hepatocellular carcinoma (HCC).

METHOD

The expression of CD28 on CD8(+), CD8(+)CD28(-)- and CD8(+)CD28(+) cell subsets in the peripheral blood obtained from 20 HCC patients and 15 healthy controls were assayed by flow cytometry.

RESULTS

The elevated percentages of CD8(+) cells, decreased percentages of CD8(+)CD28(+) cells and increased percentages of CD8(+)CD28(-)- cells were observed in the peripheral blood of HCC patients as compared with those of the control group (P<0.01). Positive correlation between the percentage of CD8(+)CD28(-)- cells and that of CD8(+) cells were found.

CONCLUSION

CD28 expression on CD8(+) T cells was aberrant in the peripheral blood of HCC patients, and the elevation of CD8(+)CD28(-)- cell number results in the increase of CD8(+) cell number.

Essential role of NHE3 in facilitating formate-dependent NaCl absorption in the proximal tubule

The absorption of NaCl in the proximal tubule is markedly stimulated by formate. This stimulation of NaCl transport is consistent with a cell model involving Cl(-)-formate exchange in parallel with pH-coupled formate recycling due to nonionic diffusion of formic acid or H(+)-formate cotransport. The formate recycling process requires H(+) secretion. Although Na(+)-H(+) exchanger isoform NHE3 accounts for the largest component of H(+) secretion in the proximal tubule, 40-50% of the rates of HCO absorption or cellular H(+) extrusion persist in NHE3 null mice. The purpose of the present investigation is to use NHE3 null mice to directly test the role of apical membrane NHE3 in mediating NaCl absorption stimulated by formate. We demonstrate that formate stimulates NaCl absorption in the mouse proximal tubule microperfused in vivo, but the component of NaCl absorption stimulated by formate is absent in NHE3 null mice. In contrast, stimulation of NaCl absorption by oxalate is preserved in NHE3 null mice, indicating that oxalate-stimulated NaCl absorption is independent of Na(+)-H(+) exchange. The virtually complete dependence of formate-induced NaCl absorption on NHE3 activity raises the possibility that NHE3 and the formate transporters are functionally coupled in the brush border membrane.

Identification of a chloride-formate exchanger expressed on the brush border membrane of renal proximal tubule cells

A key function of the proximal tubule is retrieval of most of the vast quantities of NaCl and water filtered by the kidney. Physiological studies using brush border vesicles and perfused tubules have indicated that a major fraction of Cl(-) reabsorption across the apical membrane of proximal tubule cells occurs via Cl(-)-formate exchange. The molecular identity of the transporter responsible for renal brush border Cl(-)-formate exchange has yet to be elucidated. As a strategy to identify one or more anion exchangers responsible for mediating Cl(-) reabsorption in the proximal tubule, we screened the expressed sequence tag database for homologs of pendrin, a transporter previously shown to mediate Cl(-)-formate exchange. We now report the cDNA cloning of CFEX, a mouse pendrin homolog with expression in the kidney by Northern analysis. Sequence analysis indicated that CFEX very likely represents the mouse ortholog of human SLC26A6. Immunolocalization studies detected expression of CFEX, but not pendrin, on the brush border membrane of proximal tubule cells. Functional expression studies in Xenopus oocytes demonstrated that CFEX mediates Cl(-)-formate exchange. Taken together, these observations identify CFEX as a prime candidate to mediate Cl(-)-formate exchange in the proximal tubule and thereby to contribute importantly to renal NaCl reabsorption. Given its wide tissue distribution, CFEX also may contribute to transcellular Cl(-) transport in additional epithelia such as the pancreas and contribute to transmembrane Cl(-) transport in nonepithelial tissues such as the heart.

[Alien chromosomal identification in VE161 wheat]

VE161 wheat which has the function of promotting homoeologous pairing is a male sterile substitution line or a fertile addition line with one pair of alien chromosomes from Agropyron elongatum. The alien chromosome in VE161 wheat was detected by means of techniques of total genomic DNA in situ hybridization, RFLP and double-ditelo chromosomal analysis. The results from in situ hybridization confirmed that the alien chromosome was derived from Agropyron elongatum. The RFLP analysis showed that it belongs to fourth homoeologous group, and the results from double-ditelo chromosomal analysis gave evidence that 4B chromosome was replaced in the substitution line, so it can be concluded that, in VE161 wheat, the alien chromosome would be 4E and the replaced wheat chromosome would be 4B in the substitution line. The reason for the replaced chromosome identified as 7B in a earlier study might be due to the rearrangement occurred in the genome of wheat.

Role of sodium/hydrogen exchanger isoform NHE3 in fluid secretion and absorption in mouse and rat cholangiocytes

Na+/H+ exchanger (NHE) isoforms play important roles in intracellular pH regulation and in fluid absorption. The isoform NHE3 has been localized to apical surfaces of epithelia and in some tissues may facilitate the absorption of NaCl. To determine whether the apical isoform NHE3 is present in cholangiocytes and to examine whether it has a functional role in cholangiocyte fluid secretion and absorption, immunocytochemical studies were performed in rat liver with NHE3 antibodies and functional studies were obtained in isolated bile duct units from wild-type and NHE3-/- mice after stimulation with forskolin, using videomicroscopic techniques. Our results indicate that NHE3 protein is present on the apical membranes of rat cholangiocytes and on the canalicular membrane of hepatocytes. Western blots also detect NHE3 protein in rat cholangiocytes and isolated canalicular membranes. After stimulation with forskolin, duct units from NHE3-/- mice fail to absorb the secreted fluid from the cholangiocyte lumen compared with control animals. Similar findings were observed in isolated bile duct units from wild-type mice and rats in the presence of the Na+/H+ exchanger inhibitor 5-(N-ethyl-N-isopropyl)-amiloride. In contrast, we could not demonstrate absorption of fluid from the canalicular lumen of mouse or rat hepatocyte couplets after stimulation of secretion with forskolin. These findings indicate that NHE3 is located on the apical membrane of rat cholangiocytes and that this NHE isoform can function to absorb fluid from the lumens of isolated rat and mouse cholangiocyte preparations.

[Indicators of quality of care in nursing homes from the perspective of elderly residents]

The purpose of this study was to explore the indicators of quality of care in nursing homes from the perspective of residents. A qualitative research method with in-depth interviews and participant observation was used to collect the data. Sample consisted of 10 residents from three accredited nursing homes in Keelung, Chia-I, and Kaohsiung. The study found 7 groups of indicators of quality of care for nursing homes including indicators of environment, nursing professional competence, quality assurance, basic human rights, direct care attitude, social interaction, and needs satisfaction. Findings of this study may sensitize long-term care professionals to the needs of nursing home residents. These findings can also provide a basis for setting indicators for nursing home quality evaluation and for further improvement of the life quality of nursing home residents.

The processing of coreference for reduced expressions in discourse integration

Three reading-time experiments in Chinese are reported that test contrasting views of how pronominal coreference is achieved. On the one hand, studies of reading time and eye tracking suggest that reduced expressions, such as the pronoun he, serve as critical links to integrate separate utterances into a coherent model of discourse. On the other hand, probe-word recognition studies indicate that full anaphoric expressions, such as a repeated name, are more readily interpreted than reduced expressions due to their rich lexical information, which provides effective cues to match the representation of the appropriate referent in memory. The results indicate that the ease of integrating the critical referent into a model of discourse is a function of the congruence of lexical, semantic, and discourse features conveyed by a syntactically prominent reduced expression within linguistic input. This pattern supports the view that a reduced expression is interpreted on-line and indeed plays a critical role in promoting discourse coherence by facilitating the semantic integration of separate utterances.

Oxidation of nitric oxide in a two-stage chemical scrubber using dc corona discharge

The dc corona was studied as an alternative for NO oxidation in a two-stage chemical scrubber. The dc corona plasma reactor completely oxidized 150ppm of NO to NO2 in an air stream. The NO2 was further oxidized at a higher voltage. For some cases, the NO2 in the effluents of the plasma reactor was absorbed quantitatively by a caustic sodium sulfite aqueous solution in a 2l bubble column gas absorber. The outlet concentrations of both NO and NO2 from the plasma-scrubber combination system (corona-induced chemical scrubber) were below the detection limit of the chemiluminescent NOx analyzer.

The use of schematic knowledge about sources in source monitoring

Source monitoring refers to mental processes leading to attributions regarding the origin of information. We tested Johnson, Hashtroudi, and Lindsay's (1993) assumption that prior source-relevant knowledge is used in some source-monitoring tasks. In two experiments using different domains of schematic knowledge, two sources presented information that was expected for one source and somewhat unexpected for the other. In a later source-monitoring test, participants decided whether items had been presented by Source A, by Source B, or were new. The results of both experiments show that source identification is better for expected items than for somewhat unexpected items. Multinomial modeling analyses revealed that when participants do not remember the source of information, they guess that it was presented by the expected source. These results provide evidence for the claim that source monitoring can be based on prior knowledge and support a guessing hypothesis.

Removal of chromium from abrasive blast media by leaching and electrochemical precipitation

Water is effective in leaching out Cr6+ from a mixture of paint powders and abrasive blast media. However, acids such as HNO3, HCl, and H2SO4 significantly enhance the leaching procedure. Cr ions in the leaching solutions are successfully removed by electrochemical precipitation. The consumable Fe electrodes generate ferrous ions to cause the reduction of Cr6+ to Cr3+. Cr3+ ions along with Fe2+ and Fe3+ are then removed mainly by precipitation as Cr(OH)3, Fe(OH)2, and Fe(OH)3 near the cathode where OH- ions are generated by water electrolysis. The electrochemical process is capable of discharging low levels of Cr6+, less than 1 mg/L, without pH adjustment.

Induction of integrin-associated protein (IAP) mRNA expression during memory consolidation in rat hippocampus

We have previously demonstrated that hippocampal integrin-associated protein (IAP) gene expression is associated with memory formation in a one-way inhibitory avoidance learning in rats. In the present study, we further investigated the role and mechanism of IAP involved in memory consolidation in rats. Because of the minute amount of IAP present in the brain, we have adopted the quantitative reverse transcription-polymerase chain reaction (RT-PCR) method. Our results revealed that hippocampal IAP mRNA expression is approximately fourfold higher in rats showing good memory retention (GM, retention score of 600 s) at 3 h, but not at other time points, after training when compared with the poor memory rats (retention score < 80 s). On the other hand, integrin alphav mRNA level was markedly increased ( approximately twofold), while integrin beta3 mRNA level was decreased ( approximately 50%) at 1 h post-training. Further, separate sets of RT-PCR analysis revealed that IAP5 and IAP6 mRNA expressions, but not that of IAP7, were markedly increased in GM rats 3 h post-training. Moreover, regional distribution studies revealed that different isoforms of the IAP gene are similarly distributed in different brain areas, while IAP7 has been the predominant form present in astrocyte cells. These results together suggest that IAP mRNA expression is indeed induced upon training, rather than that the GM rats have constitutively higher levels of IAP. The unparallel change of IAP and integrin mRNA expressions as far as time-course is concerned suggests that they are possibly involved in different forms and stages of memory processing. Further, IAP5 and IAP6 are more closely associated with memory consolidation, while IAP7 may constitute the major isotype for signal transduction in astrocyte cells.

A survey of home nursing services in Taiwan

This study investigated the current situation of home nursing services in Taiwan. A total of 93 home nursing agencies (response rate of 75%) responded to a mail survey. The majority of the agencies (63%) had been established within the last 3 years before the survey, were hospital-based (90%), and had less than 60 (89.3%) average total number of visits per month per nurse. Most of the home care nurses had taken home care nursing training courses and had at least 2 years of clinical experience. Half of the agencies provided care for patients on a respirator, and 28% provided in-home hospice care. Almost a third of the agencies performed poorly in the areas of supply management, supervision of home visits, and quality monitoring and improvement mechanisms. Several suggestions for the development of home nursing services in Taiwan are made.

Mechanism of proximal tubule bicarbonate absorption in NHE3 null mice

NHE3 is the predominant isoform responsible for apical membrane Na(+)/H(+) exchange in the proximal tubule. Deletion of NHE3 by gene targeting results in an NHE3(-/-) mouse with greatly reduced proximal tubule HCO(-)(3) absorption compared with NHE3(+/+) animals (P. J. Schultheis, L. L. Clarke, P. Meneton, M. L. Miller, M. Soleimani, L. R. Gawenis, T. M. Riddle, J. J. Duffy, T. Doetschman, T. Wang, G. Giebisch, P. S. Aronson, J. N. Lorenz, and G. E. Shull. Nature Genet. 19: 282-285, 1998). The purpose of the present study was to evaluate the role of other acidification mechanisms in mediating the remaining component of proximal tubule HCO(-)(3) reabsorption in NHE3(-/-) mice. Proximal tubule transport was studied by in situ microperfusion. Net rates of HCO(-)(3) (J(HCO3)) and fluid absorption (J(v)) were reduced by 54 and 63%, respectively, in NHE3 null mice compared with controls. Addition of 100 microM ethylisopropylamiloride (EIPA) to the luminal perfusate caused significant inhibition of J(HCO3) and J(v) in NHE3(+/+) mice but failed to inhibit J(HCO3) or J(v) in NHE3(-/-) mice, indicating lack of activity of NHE2 or other EIPA-sensitive NHE isoforms in the null mice. Addition of 1 microM bafilomycin caused a similar absolute decrement in J(HCO3) in wild-type and NHE3 null mice, indicating equivalent rates of HCO(-)(3) absorption mediated by H(+)-ATPase. Addition of 10 microM Sch-28080 did not reduce J(HCO3) in either wild-type or NHE3 null mice, indicating lack of detectable H(+)-K(+)-ATPase activity in the proximal tubule. We conclude that, in the absence of NHE3, neither NHE2 nor any other EIPA-sensitive NHE isoform contributes to mediating HCO(-)(3) reabsorption in the proximal tubule. A significant component of HCO(-)(3) reabsorption in the proximal tubule is mediated by bafilomycin-sensitive H(+)-ATPase, but its activity is not significantly upregulated in NHE3 null mice.

[Relationship between the familial nonrandom chromosome loss (NCL) and leukomogenesis]

By using R-banding karyotypic analysis technique, the bone marrow (BM) cells were performed in 223 hematopoietic malignacies and 105 diopathic throbocytopenic purpura (ITP), which served as control. The following results were obtained: (1) Nonrandom chromosome loss (NCL), such as, -11, -14, -21, etc, which were found in the affected members of leukemia families, were found in about 30% sporadic ANLL, MDS and about 50% ALL, espedislly in 100% (5/5) CLL, but not found in ITP (P < 0.001). These results indicated that the familial nonrandom chromosome loss were associated with leukomogenesis. (2) Because most of BM cells are hypodiploed and have the same kinds of NCL in each cases of CLL, which can develop into ALL, ANLL and also cancers, ALL BM hypo- and hyper-diploid and/or polyploid cells might be origin of hypodiploid cells. (3) 28% (6/21) of pediatric patients with AL, MDS, or FA (Fanconi Anemia) have one parent, who have up to 30% BM hypodiploid cells and similar kinds of NCL and also have the rearrangement of C-erbB and abnormal proliferation of BM. The NCL were found in the three consecutive generations of a family with 5 ALL among 10 members of third generation. It indicated that the familial NCL might be inherited and be coded by a unknown gene alteration, which might be related to leukomo and carcinogenesis, because there are genes or their candidates for leukemia in the chromosomes 11, 14 and 21. (4) Based on the works of my colleages and I, the model of leukomo and carcinogenesis was proposed and the relationship between chromosome monosomy, deletion, translocations and leukomogenesis were showed elswhere. The significance of monosomy 11, 14 and 21 etc. were discussed briefly.

Corrected relationship between %dd(10)x and stopping-power ratios

Kosunen and Rogers [Med. Phys. 20, 1181-1188 (1993)] presented a linear equation relating the Spencer-Attix water/air stopping power ratio to %dd(10)x, the photon component of the percentage depth-dose at 10 cm depth for a 10x10 cm2 field on the surface of a phantom at SSD=100 cm. This relationship has been used to calculate extensive tables of kQ factors for use with dosimetry protocols based on absorbed-dose calibration factors. Unfortunately, the original paper contained an error which has recently been assessed (Yang et al.). The present paper presents a corrected form of this relationship, viz.: (L/p)water(air)=1.275-0.00231[%dd(10)x] which is based on corrected values of %dd(10)x. It is shown that despite changes of up to 2% in calculated values of %dd(10)x, the net effect on calculated values of kQ is less than 0.2%.

Characterization of recombinant type II collagen: arthritogenicity and tolerogenicity in DBA/1 mice

Recombinant human type II collagen (rhCII) was produced using both the HT1080 mammalian cell expression system (rhCIIht) and a baculovirus expression system (rhCIIbac). The biosynthesis of CII requires extensive post-translational modifications, such as the hydroxylation of prolyl and lysyl residues and glycosylation of hydroxylysyl residues. Amino acid analyses indicated that the rhCIIbac was adequately hydroxylated at prolyl residues but underhydroxylated at lysyl residues and underglycosylated compared with tissue-derived hCII, while rhCIIht was hyperhydroxylated and hyperglycosylated at lysyl residues. When the murine collagen-induced arthritis (CIA) model was used to investigate the immunological properties of the two forms of recombinant CII, each induced a high incidence of arthritis following immunization of susceptible mice when emulsified with complete Freund's adjuvant (CFA). However, the severity of the arthritis, as assessed by the number of affected limbs, was significantly higher in mice immunized with rhCIIht than in mice immunized with rhCIIbac. These data indicate that the degree of hydroxylysine glycosylation may play a role in the induction of the arthritogenic response to CII. Each of the recombinant collagens was comparable to tissue-derived hCII in their ability to induce tolerance and suppress arthritis when given as intravenous or oral tolerogens. Taken together, our data suggest that recombinant CII can be prepared in adequate amounts for therapeutic uses and that the material is immunologically comparable to tissue-derived hCII when used to induce tolerance.

Rosai-Dorfman disease with primary cutaneous manifestations--a case report

Rosai-Dorfman disease (sinus histiocytosis with massive lymphadenopathy) is a benign systemic proliferative disorder of histiocytes resembling the sinus histiocytes of lymph nodes. The typical clinical features of this disease include bilateral painless lymphadenopathy, fever, and polyclonal hyperglobulinaemia. The condition may present with extranodal involvement in 43% of cases, and cutaneous lesions are the most common form of extranodal diseases. However, purely cutaneous Rosai-Dorfman diseases occur rarely, particularly among Orientals. We describe a 48-year-old female presenting with an erythematous dermal nodule on the abdomen. Complete physical examinations and laboratory tests demonstrated that the lesion was only limited to the skin. Histologically, the lesion consisted of proliferative large histiocytes frequently exhibiting emperipolesis. Immunohistochemical and ultrastructural studies were also performed. The former showed characteristic cytoplasmic staining of histiocytes against S-100 protein. Because cutaneous Rosai-Dorfman disease may be unfamiliar to most pathologists, cases limited to the skin are probably underestimated.

Direct evidence for the role of neuropeptide Y in sympathetic nerve stimulation-induced vasoconstriction

Neuropeptide Y (NPY) is a vasoconstrictor peptide and a cotransmitter with norepinephrine (NE) in sympathetic nerve terminals and is thought to be involved in sympathetic nerve stimulation (SNS)-induced vasoconstriction. Using BIBP-3226, a Y1 receptor selective antagonist, we examined this hypothesis in the isolated and perfused mesenteric vascular bed. SNS produced a frequency-dependent increase in perfusion pressure and concomitant overflow of NPY immunoreactivity in the perfusate. [Leu31,Pro34]NPY potentiated NE-induced and ATP-induced vasoconstriction, indicating the presence and biological action of Y1 receptors in this vascular bed. The potentiation effect of [Leu31,Pro34]NPY of the increase in perfusion pressure by NE, ATP, or SNS was prevented by BIBP-3226. In addition, SNS-induced vasoconstriction at both high and low frequencies was significantly attenuated by BIBP-3226 at a concentration that completely blocked the [Leu31,Pro34]NPY-induced potentiation of the NE- or ATP-induced vasoconstrictor effect. These results suggest that approximately 30% of vasoconstriction produced by SNS depends on NPY in the mesenteric vascular bed.

Role of neuropeptide Y in cold stress-induced hypertension

Chronic cold stress (4 degrees C) produced a sustained increase in mean arterial pressure in both normotensive and borderline hypertensive rats (BHR). The high blood pressure in BHRs was significantly reversed by a neuropeptide Y (NPY) Y1 receptor antagonist suggesting that NPY is involved in mediating stress-induced hypertension. Corresponding increases in adrenal NPY messenger RNA and NPY immunoreactivity were found during the stress; furthermore, chronic cold stress also potentiated the pressor response of rats to a subsequent acute stress test in which NPY has been shown to play a role. These results suggest that chronic cold stress-induced hypertension is mediated by elevated NPY release and vascular tone as a result of increased NPY gene expression and storage.

Sodium/hydrogen exchanger gene defect in slow-wave epilepsy mutant mice

The "housekeeping" sodium/hydrogen exchanger, NHE1, mediates the electroneutral 1:1 exchange of Na+ and H+ across the plasma membrane. NHE1 is ubiquitous and is studied extensively for regulation of pHi, cell volume, and response to growth factors. We describe a spontaneous mouse mutant, slow-wave epilepsy, (swe), with a neurological syndrome including ataxia and a unique epilepsy phenotype consisting of 3/sec absence and tonic-clonic seizures. swe was fine-mapped on Chromosome 4 and identified as a null allele of Nhe1. Mutants show selective neuronal death in the cerebellum and brainstem but otherwise are healthy. This first example of a disease-causing mutation in an Nhe gene provides a new tool for studying the delicate balance of neuroexcitability and cell survival within the CNS.

Neuropeptide Y-ATP interactions and release at the vascular neuroeffector junction

1. The ability of neuropeptide Y (NPY) to potentiate the contractile effect of ATP was examined using the perfused mesenteric arterial bed as a model of the vascular neuroeffector junction. 2. NPY (10(-9)-10(-7) M) and the NPY-Y1 selective agonist, Leu31Pro34 NPY (10(-9)-10(-7) M) both produced a concentration dependent potentiation of the ATP (1 and 3 mM) induced increase in perfusion pressure while the NPY-Y2 selective agonist, NPY 14-36 did not. 3. The NPY-Y1 selective antagonist BIBP 3226 (10-100 nM) produced a significant concentration dependent blockade of the Leu31Pro34 NPY (30 nM) induced potentiation of the ATP (3 mM) induced increase in perfusion pressure. These results are consistent with the NPY-induced potentiation of ATP effect being due to activation of the NPY-Y1 receptor subtype. 4. Periarterial nerve stimulation (supramaximal voltage, 8 and 16 Hz, 30s caused a release of ATP, as well as metabolites, from the perfused mesenteric arterial bed. KCl evoked (50 mM, 5 min) release of ATP from nerve growth factor (NGF) differentiated PC12 cells. 5. Endothelin-1 (ET-1) produced a concentration dependent (10(-15)-10(-8) M) inhibition of the K-1-evoked release of ATP from NGF-differentiated PC12 cells. This effect was mimicked by the selective ETB agonists, BQ 3020, STX-6C and IRL 1620. The ETA/ETB antagonist PD142893 blocked the inhibitory effect of ET-1. These results are consistent with the ET-1 induced inhibition of the evoked release of ATP being due to activation of ETB receptors.

Overexpression of the natural recO sequence and its effects on DNA repair of Escherichia coli

The recO gene is required for the RecF pathway of recombination and the repair of DNA daughter-strand gaps in Escherichia coli. In this work, the structural portion of recO was synthesized by the polymerase chain reaction (PCR) and cloned onto expression vectors at their Nco1 fusion cloning site, to eliminate the presence of mRNA leader sequence. While the plasmid carrying a Ptac promoter failed to overproduce RecO, the plasmid carrying a T7O10 promoter overproduced RecO in large quantity, indicating that the natural recO may be overexpressed. An increase of intracellular RecO, which may be due to the increased recO gene copies or to the induction of RecO synthesis, increased the UV resistance of recA, recF, and ssb cells, but did not increase the UV resistance of uvrB, uvrB recF, uvrB recA and uvrB ssb cells. We suggest that an increase of intracellular RecO may allow some recombination-deficient cells to perform more excision repair, thus increasing the survival. The possible causes for RecO overproduction on excision repair, and for the differential expression of recO by the Ptac and T7 promoter plasmids are discussed.

Neuropeptide-Y-ATP interactions at the vascular sympathetic neuroeffector junction

Neuropeptide Y (NPY) and ATP are considered cotransmitters with norepinephrine (NE) in sympathetic neurons innervating some blood vessels, including those of the mesentery. A prominent action of NPY is to potentiate the postjunctional contractile effect of NE as well as that of other vasoactive agents. We wished to investigate whether NPY also potentiates the contractile effect of ATP and, if so, to determine which receptor subtype mediates such an effect. The effect of NPY, the NPY-Y1-selective agent Leu31Pro34 NPY, and the NPY-Y2-selective fragment NPY 14-36 on the increase in perfusion pressure produced by ATP was examined in rat perfused mesenteric arterial bed. Results demonstrated that both NPY and Leu31Pro34 NPY but not NPY 14-36 potentiated the increase in perfusion pressure produced by ATP. These results suggest that NPY acts on Y1 receptors to enhance the postjunctional response of ATP. The putative NPY antagonist PYX2, but not the putative antagonists benextramine or PYX1, attenuated the effect of NPY, indicating that PYX2 acts as an NPY antagonist in this system. A major action of NPY is to enhance the postjunctional response of both cotransmitters, ATP and NE at the vascular sympathetic neuroeffector junction in the mesenteric arterial bed, and this may be mediated by NPY-Y1 receptors.

Synergy between signal transduction pathways is obligatory for expression of c-fos in B and T cell lines: implication for c-fos control via surface immunoglobulin and T cell antigen receptors

Expression of the protooncogene c-fos is controlled by three main regulatory pathways involving kinase C, cAMP, and calcium. Kinase C mediates its effects via phosphorylation of serum response factor (SRF) which interacts with the serum response element (SRE); cAMP and calcium mediate their effects via phosphorylation of CREB (cAMP regulatory element binding protein) presumably by activation of a protein kinase A or calmodulin-regulated kinase. We have examined the function of these elements in Burkitt's lymphoma cells (Ramos and Daudi) as well as a T lymphocytic cell line (Jurkat). We have found that stimulation of any one of these pathways alone has little or no effect on c-fos induction. However, kinase C activation (PMA stimulation) combined with either cAMP (forskolin plus MIX) or calcium stimulation (ionophore) leads to greatly enhanced c-fos induction. By contrast, cAMP in the presence of calcium shows no synergy in c-fos induction. Okadaic acid augments PMA- as well as calcium-mediated activation of c-fos, and has little or no effect when combined with cAMP. The main difference between Ramos (B cells) and Jurkat (T cells) in the regulation of c-fos is that cAMP plus calcium is strongly synergistic in Jurkat and is without effect in Ramos. Analysis of AP-1 activity using gel mobility shift assays confirms that the requirements for synergy in c-fos mRNA induction are paralleled by requirements for synergy in induction of AP-1 activity. Signaling in B cells due to anti-Ig stimulation involves both kinase C activation and release of intracellular calcium, and results in c-fos mRNA induction. Our results indicate that synergy between the kinase C activation and calcium is needed for efficient c-fos induction since neither of these two alone induces c-fos well. That synergy of signaling pathways is relevant for the anti-Ig induction of c-fos is supported by the fact that cAMP-inducing agents and okadaic acid further enhance anti-Ig induction of c-fos. These results suggest that cell-specific patterns of synergy are an essential feature for c-fos induction and may be relevant for c-fos control through B and T cell antigen receptors.

[Preliminary observation on the destructive effect of chemical disinfectants in serum markers of hepatitis B and C]

Chloroform, 40% formaldehyde, 3% hydrogen peroxide solution and 75% alcohol were used to act on hepatitis B surface antigen (HBeAg), hepatitis B e antigen (HBaAg) and anti-hepatitis C virus antibody (Anti-HCV) positive serum for 5, 15, 30 and over 60 minutes. They were examined by enzyme-linked immunosorbent assay and observed for the effect. The destructive effect of chloroform on HBsAg and anti-HCV positive derum was marked. It was discovered that 40% formaldehyde solution destroyed HBsAg, HBeAg, and anti-HCV positive serm, while 75% alcohol also showed destructive effect on HBsAg, HBeAg and anti-HCV positive serum.

Effects of lipids on intestinal adaptation following 60% resection in rats

The effects of long-chain triglycerides (LCT) and of medium-chain triglycerides (MCT) on intestinal adaptation in rats were compared following a 60% resection of intestine. Sixty Long-Evans rats were divided into four groups: control (sham-operated) rats fed an MCT-enriched diet, control rats fed an LCT-enriched diet, experimental rats fed an MCT-enriched diet, and experimental rats fed an LCT-enriched diet. In the MCT-enriched diet, 90% of the fat was MCT; in the LCT diet, 90% was LCT. In each diet, 31-32% of daily caloric intake came from fat. All diets were isocaloric and isonitrogenous. Following the 60% intestinal resection from the mid-portion of the small intestine, there were significant increases in mucosal height, villous height, villous width, and crypt depth (P < 0.05). Gut weight, mucosal weight, protein and DNA content, and DNA synthetic rate also increased. In the ileum, rats receiving the LCT diet showed greater increases in gut weight, mucosal weight, crypt depth, protein and DNA content, and DNA synthetic rate than the MCT rats did (P < 0.05). In the jejunum, however, the differences were not statistically significant. In both the jejunum and the ileum, the response of the intestine was greater closer to the anastomotic site (P < 0.05). Results of these studies demonstrated that LCT had a better effect than MCT on intestinal response both structurally and functionally.

Renal cortical mitochondria are the source of oxygen free radicals enhanced by gentamicin

Rat renal cortical mitochondria were isolated from Wistar male rats weighing 80 to 120 g to investigate whether the source of oxygen free radicals was renal cortical mitochondria enhanced by gentamicin. In renal cortical mitochondria with or without the addition of gentamicin, DMSO, DFO, CAT, SOD, and MT1 were added separately, then incubated at 37 degrees C for 90 min. Superoxide anions and hydroxyl radicals were then determined. The results showed that superoxide anions and hydroxyl radicals generated in mitochondria were enhanced by the addition of in vitro gentamicin (12.4 mg/mL) when compared to those without the addition of gentamicin. Dimethylsulfoxide (DMSO), catalase (CAT), and deferoxamine (DFO) significantly inhibited hydroxyl radicals enhanced by gentamicin, but superoxide dismutase (SOD) and metallothionein-1 (MT1) did not. SOD significantly inhibited the production of superoxide anions. Our data indicated that renal cortical mitochondria are the source of oxygen free radicals and that production is enhanced by gentamicin. This provides more insight on the pathogenetic role of hydroxyl radicals and superoxide anions in gentamicin-induced nephrotoxicity in vitro.

Inhibitory effects of high molecular weight substances from CAPD dialysate on mouse bone marrow progenitor cells and lymphocyte transformation

The isolation and purification of F A1 (MW 23-64 KD), F B1 (MW 24-54 KD), F A2 and F B2 (both MW 67 KD) of high molecular weight substances (HMS) from continuous ambulatory peritoneal dialysis (CAPD) dialysate of 2 end staged renal disease (ESRD) patients (A and B) were carried out by precipitation, desalting, gradient elution, chromatography and concentration. 0.1ml of tris-buffer, 0.2ml of uremic serum. 0.1ml of F A1, F B1, 0.2ml of F A2 were separately added to mouse bone marrow culture medium and lymphocyte culture medium, then colony-forming unit of erythroid (CFU-E), burst-forming unit of erythroid (BFU-E), colony-forming unit of granulocyte-macrophage (CFU-GM) and lymphocyte transformation (LT) were measured. We found that the uremic serum and F A1, F B1 could inhibit CFU-E, BFU-E very significantly (P < 0.001) compared to the tris-buffer control, but could not inhibit CFU-GM. The uremic serum and F A1 could inhibit LT significantly (P < 0.01) compared to the tris-buffer control, while F A2 could inhibit neither CFU-E nor BFU-E. If the dosage of erythropoietin (EPO) added to mouse bone marrow progenitor cell culture medium increased 3-6 times. F A1 could not express its inhibitory effect on CFU-E or BFU-E.(ABSTRACT TRUNCATED AT 250 WORDS)

Orally administered glycolipid derivative LIGA20 reduces infarct volume and behavioral impairment after focal cerebral ischemia

The efficacy of p.o. semisynthetic glycolipid LIGA20 (II3Neu5-AcGgOse4-2-d-erythro-1,3-dihydroxy-2-dichloro-aceta mide-4-trans- octadecene) treatment in stroke was studied in a permanent left middle cerebral artery occlusion model in the rat. A dose-dependent increase of plasma LIGA20 and its presence in the brain were documented after p.o. drug application. Oral administration of 50 to 200 mg/kg of LIGA20, initiated 24 hr before middle cerebral artery occlusion and continued for 7 days, reduced the motor and cognitive impairment after the stroke, measured by the rotarod and the passive avoidance test, respectively. The 10-mg/kg dose was effective when given i.v. but not p.o. Oral treatment with 100 mg/kg of LIGA20 reduced the infarct size in the cortex but not in the ischemic core (the striatum). No biochemical or behavioral adverse effects of LIGA20 treatment were observed. Further studies are needed to evaluate the full therapeutic potential of this compound.

Zinc-induced metallothionein synthesis could protect from gentamicin nephrotoxicity in suspended proximal tubules of rats

We have reported that preinjection of zinc could ameliorate gentamicin-induced nephrotoxicity in vivo via the induction of metallothionein. The present project was designed to study whether preinjection of zinc could protect from the harmful effects of gentamicin on DNA synthesis, Na(+)-K(+)-ATPase activity, and free radical production in rat renal proximal tubules (PT) in vitro. PT were prepared and cultured from normal, saline-preinjected, and Zn-preinjected (Zn 10 mg/k/day s.c. 5 days) Wistar male rats weighing 80-120 g. The results showed that DNA synthesis and Na(+)-K(+)-ATPase activity were significantly suppressed in the normal and saline-preinjected rats' PT by addition of gentamicin to the media in the concentration of 12.4 mg/mL; however, these reactions were not suppressed by gentamicin in Zn-preinjected rats' PT, and malondialdehyde and hydroxyl radical production in Zn-preinjected rats' PT were significantly lower than those in the normal and saline-preinjected rats' PT (p < .01). On the other hand, the metallothionein in Zn-preinjected rats' PT was very significantly higher than that in the normal and saline-preinjected rats' PT (p < .001). Our data indicate that gentamicin-induced suppression of DNA synthesis and Na(+)-K(+)-ATPase activity in rat PT, which lead to renal injury, may be relevant to free radicals generated by gentamicin; and that preinjection of zinc could ameliorate gentamicin-induced nephrotoxicity via the induction of the metallothionein synthesis in rat PT to scavenge free radicals generated by gentamicin.

DNA sequence polymorphism of the Chlamydia trachomatis omp1 gene

The Chlamydia trachomatis major outer membrane protein gene (omp1) was amplified by polymerase chain reaction (PCR) from 89 clinical specimens, and restriction fragment length polymorphism (RFLP) patterns were analyzed after AluI or AluI and MspI digestion. Ten distinct RFLP omp1 genotypes were observed, although 4 types accounted for 70% of the isolates. The DNA sequence of variable domains (VDs) 1, 2, and 4 were determined for 49 samples. Thirty samples (61%) had prototype VD sequences, 15 (31%) had sequences that varied from prototype sequences, and 4 (8%) contained sequences from > 1 chlamydial isolates. Eleven of the 15 DNA sequence variations were one- or two-site nucleotide substitutions, 10 of which resulted in an amino acid change. Four DNA sequence variations were more extensive, with multiple nucleotide substitutions, insertions, or deletions. The data demonstrate that C. trachomatis isolates circulating in a relatively circumscribed geographic community exhibit remarkable omp1 DNA sequence polymorphism.

Autoantibodies to cartilage collagens in relapsing polychondritis

Relapsing polychondritis is a systemic disease associated with a destruction of cartilage in various parts of the body. Sera from six patients with relapsing polychondritis and one patient with microscopic polyarteritis nodosa as well as from six controls were analyzed by immunoblotting and ELISA. All patients had autoantibodies against native collagens II and IX. The serum from one patient showed a strong reaction with all three collagen chains of the high molecular weight fraction of collagen IX after denaturation; sera from four patients showed autoantibodies against alpha 2 (XI) and sera from three patients showed autoantibodies against the covalently cross-linked gamma component of collagen XI. The presence of autoantibodies against collagens II, IX, and XI, which form the major fibrillar scaffold in cartilage and mediate the interaction of collagen fibrils and proteoglycan, suggests that autoantibodies against cartilaginous collagen may play a crucial role in the pathogenesis of relapsing polychondritis and microscopic polyarteritis nodosa.

Collagen II from articular cartilage and annulus fibrosus. Structural and functional implication of tissue specific posttranslational modifications of collagen molecules

Collagen II was isolated and characterized from hyaline cartilage (articular cartilage) and fibro-cartilage (annulus fibrosus). Collagen II from the latter tissue has a substantially higher degree of hydroxylation and glycosylation than that isolated from articular cartilage. The higher degree of posttranslational modification was associated with a slower electrophoretic mobility, a greater resistance to mammalian collagenase digestion and a higher thermal stability. An increase of glycosylation accelerates the initial steps in fibril formation of collagen molecules but slows down the following lateral growth. The newly formed aggregates of collagen II from annulus fibrosus consisted of fibrils with a smaller diameter.

Submicrostructure and typing of female genital condylomata

Thirty biopsies from female genital condylomata were examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to study structural characteristics and typing of condylomata. It was found that cytoplasmic clearing was marked in acuminate condylomata, diffuse interstitial and epithelial proliferation in nodular condylomata (flat condylomata), and invagination of the lesions into the interstitial tissue or glandular ducts in endophytic condylomata. In nodular condylomata, SEM also showed some structural features similar to those of intra-epithelial neoplasia. Microridges on the surface of squamous cells had villiform of granular changes. On the surface of a percentage of squamous or columnar cells, there were holes with a diameter of about 3 to 5 microns. A number of giant cells were seen among other cells. The cervical squamatization zone contained groups of special cells covered with dense microvilli. TEM of nodular condylomata revealed some pictures resembling active proliferation of tumor cells, such as enlarged or irregular nuclei (large N/C ratio), evaginated or invaginated nuclear membranes, condensed chromatin attached to the inner part of the nuclear membrane, transparent nucleoplasm, and frequent nucleosomes and karyokinesis. Virus particles with the morphological characteristics of HPV (naked hexagon-like particles with an average diameter of 45-50 nm) were seen in some nuclei with markedly condensed chromatin. It is suggested that HPV-induced genital condylomata, especially nodular one (flat condylomata), entail a potential progression to malignancy.

Identification of highly conserved and species-specific polypeptides of Haemophilus ducreyi

Chancroid is a sexually transmitted diseased caused by Haemophilus ducreyi. The pathological manifestations of chancroid are unique among Haemophilus species and the virulence factors of H. ducreyi that account for these features have not been identified. Some of these virulence factors may be unique components of H. ducreyi, but attempts to identify H. ducreyi-specific components have been unsuccessful. Four polypeptides--A, B, C and D of 83, 77, 56 and 28 kDa, respectively--were identified with a panel of nine H. ducreyi-specific monoclonal antibodies (MAbs). Polypeptide C was one of the five major proteins in H. ducreyi and demonstrated micro-heterogeneity in SDS-PAGE. Polypeptides A, B and D were present in only small amounts in whole-cell lysates of H. ducreyi. The relative amounts of A and B varied, suggesting that they may be precursor molecules. The unique polypeptides C and D were not exposed on the surface. Polypeptide C was highly soluble and did not appear to be membrane-bound, whereas polypeptide D appeared to partition with the cytoplasmic membrane and was soluble in Sarkosyl. All four polypeptides appeared to be unique to H. ducreyi since MAbs directed against them did not cross-react with H. influenzae, H. parainfluenzae or Neisseria gonorrhoeae. The mol. wts of all of these polypeptides were conserved throughout 35 clinical isolates collected from 15 cities in eight countries and one reference strain of H. ducreyi that were tested.(ABSTRACT TRUNCATED AT 250 WORDS)

Topical application of local anesthetics for postoperative analgesia in children undergoing circumcision

Circumcision often followed by severe pain during the postoperative period. Forty boys, ASA class I, presenting for day case circumcision were allocated randomly to receive either 4% prilocaine hydrochloride spray or 1.1% dipucaine ointment at the end of the operation. Analgesia was assessed by a single observer utilizing a three-point scale in recovery room. The parents were asked to complete the questionnaire 8h following operation and on the morning of the first postoperative day. At approximately 24h following operation an assessment of the child's activity level was made by the parents. The frequency of taking the oral analgesia was also recorded. Both topical analgesics provided satisfied analgesia during the postoperative period and no complication was noted. Only one patient in dipucaine group vomited in the recovery room. We conclude that topical use of prilocaine hydrochloride and dipucaine can provide a simple, safe and adequate analgesia for post-circumcision pain relief.

High-level expression of the rat whey acidic protein gene is mediated by elements in the promoter and 3' untranslated region

The high-level expression of the rat whey acidic protein (WAP) gene in transgenic mice depends on the interaction of 5'-flanking promoter sequences and intragenic sequences. Constructs containing 949 bp of promoter sequences and only 70 bp of 3'-flanking DNA were expressed at uniformly high levels, comparable to or higher than that of the endogenous gene. Although this WAP transgene was developmentally regulated, it was expressed earlier during pregnancy than was the endogenous WAP gene. Replacement of 3' sequences, including the WAP poly(A) addition site, with simian virus 40 late poly(A) sequences resulted in an approximately 20-fold reduction in the expression of WAP mRNA in the mammary gland during lactation. Nevertheless, position-independent expression of the transgene was still observed. Further deletion of 91 bp of conserved WAP 3' untranslated region (UTR) led to integration site-dependent expression. Position independence was restored following reinsertion of the WAP 3' UTR into the deleted construct at the same location, but only when the insertion was in the sense orientation. The marked differences observed between the expression levels of the 3'-end deletion constructs in transgenic mice were not seen in transfected CID 9 mammary epithelial cells. In these cells, expression of the endogenous WAP gene was dependent on the interaction of these cells with a complex extracellular matrix. In contrast, the transfected WAP constructs were not dependent on extracellular matrix for expression. Thus, both the abnormal expression of WAP in cells cultured on plastic and the precocious developmental expression of WAP in transgenic mice may reflect the absence of a negative control element(s) within these recombinant constructs.

Molecular cloning of the cDNA for the catalytic subunit of human DNA polymerase delta

The cDNA of human DNA polymerase delta was cloned. The cDNA had a length of 3.5 kb and encoded a protein of 1107 amino acid residues with a calculated molecular mass of 124 kDa. Northern blot analysis showed that the cDNA hybridized to a mRNA of 3.4 kb. Monoclonal and polyclonal antibodies to the C-terminal 20 residues specifically immunoblotted the human pol delta catalytic polypeptide. A multiple sequence alignment was constructed. This showed that human pol delta is closely related to yeast pol delta and the herpes virus DNA polymerases. The levels of pol delta message were found to be induced concomitantly with DNA pol delta activity and DNA synthesis in serum restimulated proliferating IMR90 cultured cells. The human pol delta gene was localized to chromosome 19 by Southern blotting of EcoRI digested DNA from a panel of rodent/human cell hybrids.

Fulvic acid disturbs processing of procollagen II in articular cartilage of embryonic chicken and may also cause Kashin-Beck disease

Kashin-Beck disease is an endemic osteoarthropathy in China which may lead to skeletal deformation and dwarfism. We have analysed articular cartilage from two patients and found an accumulation of the precursor molecule, pro-pN-collagen II (pN, peptide attached at the amino-terminus) which was not present in extracts of control fetal cartilage. In addition, collagen II isolated from the same tissue by limited pepsin digestion had a decreased electrophoretic mobility, increased proline hydroxylation and decreased thermal stability. Previously, a genetic defect in pro-pN-collagen-I processing has been described in calf and sheep (dermatosparaxis) and man (Ehlers-Danlos, type VII) which caused an extreme fragility of the skin [Lenaers, A., Ansay, M., Nusgens, B.V. & Lapière, C.M. (1971) Eur. J. Biochem. 23, 533-541; Helle, O. & Nes, N.J. (1972) Acta Vet. Scand. 13, 443-445; Lichtenstein, J.R., Martin, G.R., Kohn, L.D., Byers, P.H. & McKusick, V.A. (1973) Science 182, 298-300]. Accordingly, one may assume that the impaired conversion of pro-pN-collagen II to collagen II and the structural alteration of collagen II, presumably caused by fulvic acid and other environmental factors, play an important role in the pathogenesis of Kashin-Beck disease.