[Polymorphism of human platelets alloantigens in Chinese patients with acute myocardial infarction and acute ischemic stroke]

OBJECTIVE

To investigate the gene frequencies of 5 major human platelets alloantigens (HPA 1 - 5) in Chinese population and to assess if polymorphism of HPA is associated with acute myocardial infarction (AMI) and acute ischemic stroke (AIS) in the Chinese.

METHODS

HPA 1 - 5 genotyping was performed with PCR using allele specific primers and restriction enzyme digestion based on PCR products in 95 AMI patients, 188 AIS patients and 270 normal controls. Gene frequency distribution was tested by Hardy-Weinberg equilibrium. Comparisons of HPA gene frequencies between the patient and control groups were made by chi(2) test.

RESULTS

The gene frequencies of HPA 1 - 5 were listed as follows: HPA1a, 91%; HPA 1b, 9%; HPA 2a, 94%; HPA 2b, 6%; HPA 3a, 83%; HPA 3b, 17%; HPA 4a, 98%; HPA 4b, 2%; HPA 5a, 97%; HPA 5b, 3%. No significant differences were found in HPA 1 - 5 gene frequencies between AMI patients and normal controls. In AIS patient group, HPA-2a allele frequency was significantly higher than that in controls, but this allele gene frequency in the two groups was very close (0.99 and 0.94, respectively) and too many subjects in the two groups were overlapped. No differences were found in the other 4 HPA systems between patients and controls.

CONCLUSION

Polymorphism of HPA is not an inherited risk factor and is not associated with Chinese arterial thrombotic diseases, such as AMI and AIS.

Prenatal X-irradiation increases GFAP- and calbindin D28k-immunoreactivity in the medial subdivision of the nucleus of solitary tract in the rat

Glial fibrillary acidic protein- (GFAP) and calbindin D28k-immunoreactivity (IR) were investigated in the medial subdivision of the nucleus of the solitary tract (mNST) of prenatally X-irradiated rats. Pregnant rats were exposed to a single whole-body X-irradiation on day 11 or 16 of gestation at a dose of 1. 3 Gy. The offspring were killed at 7-14 days of age for the immunohistochemical observations. Rat pups showed strong GFAP-IR at the level rostral to the obex when receiving X-rays on day 11 of gestation, with hypertrophy of astrocyte cell bodies and cytoplasmic processes, but weak GFAP-IR when receiving X-rays on day 16 of gestation. Calbindin D28k-IR was stronger in the animals receiving X-rays on day 11 or 16 of gestation compared to that in the control animals. In the present study, the increase of GFAP- and calbindin D28k-IR cells in the mNST might indicate that adaptative mechanisms are taking place to preserve integrated nervous system function and possibly, to provide neuroprotection.

[Role of tumor necrosis factor -alpha in the pathogenesis of pregnancy-induced hypertension]

OBJECTIVE

To investigate the role of tumor necrosis factor-alpha (TNFalpha) in the pathogenesis of pregnancy induced hypertension (PIH) by damaging endothelial cells.

METHODS

41 patients with PIH and 17 healthy pregnant women were studied. The concentration of TNFalpha in maternal plasma was measured by sensitive radioimmunoassay. The morphology of endothelial cells of placental blood vessels was observed. Endothelial cells were incubated in the presence of TNFalpha (400 U/ml) and sera (30% vol/vol) from PIH women and normal pregnant women to observe their growth and shape.

RESULTS

Maternal plasma TNFalpha level in PIH was 2.29 microgram/L +/- 0.51 microgram/L, higher than that in normal pregnancy (the latter was 1.73 microgram/L +/- 0.25 microgram/L, t = 5.60, P < 0.01). The endothelial cells of placental blood vessels in PIH revealed morphologic damages. Both sera of PIH women and TNFalpha were cytotoxic to endothelial cells in culture, including inhibition of the proliferation and morphologic changes of the cells.

CONCLUSION

Damage of the endothelial cells of placental blood vessels is associated with the abnormal increase in the maternal blood TNFalpha. Sera of PIH women can damage the endothelial cells in culture and this effect is also associated with TNFalpha.

Selective impairment of corticotropin-releasing factor1 (CRF1) receptor-mediated function using CRF coupled to saporin

CRF is the main component in the brain neuropeptide effector system responsible for the behavioral, endocrine, and physiological activation that accompanies stress activation. Reduced CRF system activation plays a role in the etiology of a variety of psychiatric and metabolic disease states. We have developed a novel protein conjugate that joins native rat/human CRF to a ribosome-inactivating protein, saporin (CRF-SAP), for the purpose of targeted inactivation of CRF receptor-expressing cells. Cytotoxicity measurements revealed that CRF-SAP (1-100 nM) produced concentration-dependent and progressive cell death over time in CRF1 receptor-transfected L cells, but at similar concentrations had no effect on CRF2alpha receptor-transfected cells. The CRF-SAP-induced toxicity in CRF1-transfected cells was prevented by coincubation with the competitive CRF1/CRF2 receptor peptide antagonist, [D-Phe12]CRF-(12-41), or the selective nonpeptide CRF1 receptor antagonist, NBI 27914. Finally, in cultured rat pituitary cells that express native CRF1 receptors, CRF-SAP suppressed CRF-induced (1 nM) ACTH release. GnRH (1-10 nM) stimulated LH release was also assessed in the same pituitary cultures. Although there was a slight decrease in LH release from these cultures, this decrease was observed with CRF-SAP or SAP alone, suggesting that the response was nonspecific. Taken together, these results suggest the utility of CRF-SAP as a specific and subtype-selective tool for long term impairment of CRF1 receptor-expressing cells.

Cardiac afferents to the nucleus of the tractus solitarius: A WGA-HRP study in the rat

Central distribution of the sensory fibers of the heart was investigated in the rat by the use of transganglionic transport of horseradish peroxidase (HRP). After the left intercostal thoracotomy was done under deep anesthesia and artificial respiration, wheat germ agglutinin-conjugated HRP (WGA-HRP) was injected into the left and right ventricular walls and the apex of the heart. HRP-labeled fibers were observed to be distributed to the dorsomedial portion of the medulla oblongata through the vagal nerve. The labeled fibers were present in various subnuclei of the nucleus of the tractus solitarius (NTS) bilaterally at the level of +0.36 to -1.74 mm to the obex. However, the most conspicuous feature in the present study was that the labeled fibers were exclusively confined to the medial, ventrolateral and commissural NTS with some distribution to the dorsolateral NTS. Although the labeling in the medial and ventrolateral NTS was observed to extend rostrocaudally, it was of interest that the labeling in the medial NTS was divided into the ventral and dorsal parts at the level around the obex. Accumulation of the labeled fibers in the commissural NTS was found at the level caudal to the obex and these fibers were traced to the caudal portion of its subnucleus with a gradual decrease in number. This pattern of distribution of cardiac afferents in the NTS was considered to be peculiar to the rat, because it was quite different from that reported previously in the cat.

The study on the expression of membrane HSP70 protein in H22 cell and its immunoprotective mechanism against carcinoma

The mRNA and protein expression of HSP70 were studied using RT-PCR and FCM techniques. It's immune protective effects in vivo and the cytotoxicity in vitro were also observed. Results showed that cell viability didn't change under 42-43 degrees C, but declined in 44-45 degrees C; the level of HSP70 mRNA decreased initially (0.5-4.0 hour) but gradually resumed and increased from 8 to 12 hours at 42 degrees C. The positive cells expressed membrane HSP70 were significantly higher in heat shocked group than in a control group (P<0.001); the highest positive rate was 96.8% at 43 degrees C. The C3H mice immunized with heat shocked H22 cells could resist a secondary subcutaneous inoculation of parental H22 cells and their tumorigenic rate was significantly lower than that in mice immunized with parental H22 cells and RPMI 1640 control mice, which were 1/9.7/8 and 8/8, respectively. Their median survival time was also longer than that of parental cell group and RPMI 1640 control group, which were >90 days, 73.5 days, and 39.5 days, respectively. Through heat-treated tumor cell and lymphocyte mixed culture (TLMC), the induced lymphocytes had higher cytotoxic activities than that of splenic cells. The cytotoxicity against H22 cells reached 65.38% (2 hrs, 42 degrees C) and 67.84% (12 hrs, 43 degrees C) and could be blocked by anti-HSP70 McAb. Phenotype analysis revealed that the rate of TCR gammadelta+ cells rose with increasing cytotoxic activity, but no similar changes could be found in the CD4+ CD8+ TCR alphabeta+ subset. These results suggest that proper heat shock conditions can improve the immunogenicity of tumor cells and CD4- CD8- TCR gammadelta+ T carried on cytotoxic function via the HSP70 molecule.

Effect of short-term ethanol exposure on the suprachiasmatic nucleus of hypothalamus: immunohystochemical study in mice

Morphological changes of the suprachiasmatic nucleus (SCN) of the hypothalamus were investigated in mice exhibiting intoxication signs of stages 2 or 3 after a short application term of 6% ethanol. Alterations in glial cells and neurons were examined using anti-glial fibrillary acidic protein (GFAP) and anti-calbindin D28k monoclonal antibody, respectively. The results revealed that short-term ethanol exposure led to strong expression of GFAP-immunoreactivity (GFAP-IR) in the dorsomedial part of the SCN. Furthermore, GFAP-IR astrocytes showed an increase in number and hypertrophy with longer processes. However, calbindin D28k-IR neurons were apparently little changed in the SCN. It is concluded that neuroadaptive response of astrocytes could occur before the neurotoxic effects emerge on neurons on the SCN.

F4/80-positive cells rapidly accumulate around tubuli recti and rete testis between 3 and 4 weeks of age in the mouse: an immunohistochemical study

PROBLEM

Previous studies demonstrated that F4/80 antigen (murine macrophage-specific antigen)-positive cells in testes of normal adult mice accumulate particularly in the interstitium adjacent to the tubuli recti and rete testis (i.e., the central region). However, it remains unknown whether this accumulation is a congenital or acquired phenomenon.

METHOD OF STUDY

The distribution of F4/80-positive cells on frozen sections of testes obtained from various aged mice was immunohistochemically examined to determine when the positive cells specifically accumulate in the central region.

RESULTS

F4/80-positive cells were homogeneously distributed throughout the testicular interstitium with no specific accumulation until 2 weeks of age. However, at 3 weeks of age, the density of positive cells in the central region became slightly, but significantly, higher than that in the interstitium between the seminiferous tubules. Between 3 and 4 weeks of age, the cell density in the central region increased rapidly, the density at 4 weeks of age reaching the level of the mature testes of 8-week-old mice.

CONCLUSION

These results demonstrate that the specific accumulation of F4/80-positive cells in the central region is an acquired phenomenon, which starts and ends before puberty.

Interleukin-4 weakens host resistance to pulmonary and disseminated cryptococcal infection caused by combined treatment with interferon-gamma-inducing cytokines

We examined the role of interleukin (IL)-4 in host resistance against infection with Cryptococcus neoformans. First, we examined the effects of a neutralizing anti-IL-4 monoclonal antibody (mAb) on survival of mice infected intratracheally with this fungal pathogen. We also compared the number of live C. neoformans in lungs and brains of treated and untreated mice. Treatment with anti-IL-4 mAb significantly prolonged survival of infected mice and reduced the lung and brain burdens of C. neoformans, which was associated with increased production of IFN-gamma in lungs. In the next experiments, infected mice were treated with two IFN-gamma-inducing cytokines, IL-12 and IL-18, known to enhance protection against infection. We then evaluated the effect of such treatment on the number of live microorganisms and concentration of IL-4 in lungs. These two parameters showed a statistically significant relationship, suggesting a negative regulation of host protection by IL-4. Finally, we examined the effects of IL-4 treatment and administration of neutralizing anti-IL-4 mAbs on host protection against C. neoformans and local production of IFN-gamma in lungs induced by treatment with IL-12/IL-18. The former treatment suppressed host protection and reduced IFN-gamma production, while the latter produced the opposite effects. Our results indicated that IL-4 suppressed the host defense mechanisms against infection with C. neoformans potentiated by IFN-gamma-inducing cytokines probably through the suppression of local production of IFN-gamma.

Major differences between the testis and epididymis in the induction of granulomas in response to extravasated germ cells. I. A light microscopical study in mice

A spermatic granuloma is a chronic inflammatory lesion which surrounds extravasated spermatozoa. Clinically, the lesion develops in the interstitial spaces of the epididymis and vas deferens, and only exceptionally in the testis itself. In the present study, murine testes and epididymides were injured using a needle and the histological appearances of these organs was then compared. Traumatic injury induced extravasation of germ cells in both testes and epididymides. A few days later, spermatic granulomas consistently formed in the epididymides, however, such lesions were not induced in the testes. To examine the possibility that epididymal spermatozoa have inherently greater ability to form spermatic granulomas than do testicular germ cells, isolated epididymal spermatozoa or testicular germ cells were locally injected into the testes and epididymides of recipient mice. Spermatic granulomas readily formed in the epididymides after local injection of either epididymal spermatozoa or testicular germ cells. In contrast, such lesions did not form in the testes even when epididymal spermatozoa were injected. Therefore, this study suggests that the microenvironment of the testicular interstitium, rather than the extravasated components from the ruptured seminiferous tubules, is the main factor determining the limited formation of spermatic granulomas in the testis.

Chemokine responses and accumulation of inflammatory cells in the lungs of mice infected with highly virulent Cryptococcus neoformans: effects of interleukin-12

We examined the mechanisms involved in the development of lung lesions after infection with Cryptococcus neoformans by comparing the histopathological findings and chemokine responses in the lungs of mice infected with C. neoformans and assessed the effect of interleukin (IL) 12 which protects mice from lethal infection. In mice infected intratracheally with a highly virulent strain of C. neoformans, the yeast cells multiplied quickly in the alveolar spaces but only a poor cellular inflammatory response was observed throughout the course of infection. Very little or no production of chemokines, including MCP-1, RANTES, MIP-1alpha, MIP-1beta and IP-10, was detected at the mRNA level using RT-PCR as well as at a protein level in MCP-1, RANTES and MIP-1alpha. In contrast, intraperitoneal administration of IL-12 induced the synthesis of these chemokines and a marked cellular inflammatory response involving histiocytes and lymphocytes in infected mice. Our findings were confirmed by flow cytometry of intraparenchymal leukocytes obtained from lung homogenates which showed IL-12-induced accumulation of inflammatory cells consisting mostly of macrophages and CD4+ alphabeta T cells. On the other hand, C-X-C chemokines including MIP-2 and KC, which attract neutrophils, were produced in infected and PBS-treated mice but treatment with IL-12 showed a marginal effect on their level, and neutrophil accumulation was similar in PBS- and IL-12-treated mice infected with C. neoforman. Our results demonstrate a close correlation between chemokine levels and development of lung lesions, and suggest that the induction of chemokine synthesis may be one of the mechanisms of IL-12-induced protection against cryptococcal infection.

The cloning of plant E2F, a retinoblastoma-binding protein, reveals unique and conserved features with animal G(1)/S regulators

Association of the retinoblastoma (Rb) protein with E2F transcription factors is central to cell cycle-specific gene expression and growth in animal cells. Whether Rb-E2F complexes are also involved in plant cell growth and differentiation is still unknown since E2F proteins have not yet been identified in plants. Here we report the isolation and characterisation of a wheat E2F (TmE2F) cDNA clone. Interestingly, the overall domain organisation of plant E2F is related to the human E2F-1/2/3 subset but its primary sequence is slightly more related to the E2F-4/5 subset. TmE2F-Rb binding depends on residues, located at the C-terminus, which are different from those of animal E2Fs. However, the acidic or hydrophobic nature of certain residues is maintained, strongly suggesting that they may have a crucial role in E2F activities. Plant E2F is expressed in proliferating cultured cells and in differentiated tissues and is up-regulated early in S phase. Our studies reinforce the idea that G(1)/S regulators in plants are unrelated to those of yeast cells but similar to those of animal cells and provide new tools to analyse the links between cell cycle regulators, plant growth and developmental signals.

Surgical treatment of patent ductus arteriosus (PDA) through mini subaxillary extrapleural approach

In this study, a new surgical technique for the surgical treatment of patent ductus arteriosus (PDA) is evaluated. The subaxillary extrapleural approach was performed on 836 patients with patent ductus arteriosus. And 20 of these patients were evaluated for postoperative outcomes compared with the routine technique. The results indicated that the new method is safe, less traumatic and has better cosmetic effects. It is concluded in this article that the subaxillary extrapleural approach for PDA is a good modification to the routine surgical technique, that is surgery through the posterolateral approach.

Association of edentulousness with systemic factors in elderly people living at home

OBJECTIVE

To examine the association of edentulousness with systemic factors: age, gender, tobacco-smoking, alcohol intake, body mass index, functioning in daily living, cortical thickness at the mandibular angle, and systemic diseases: bone-fracture (an indicator for osteoporosis), diabetes, thyroid disease, hyperparathyroidism, asthma, heart failure, hypertension.

METHODS

The study population comprised 293 elderly subjects, 124 (42%) edentulous and 169 (58%) dentate. The data from clinical and radiographic examinations and structured interviews were analyzed by multiple logistic regression.

RESULTS

When edentulousness in both the mandible and the maxilla was considered, history of bone fracture and tobacco-smoking were significantly related to complete edentulousness with odds ratios (OR) of 2.51 (95% CI: 1.47-4.28) and 2.42 (95% CI: 1.32-4.43) respectively, associations independent of age and gender. A similar association was found for the edentulous mandible. In the elderly subjects with an edentulous maxilla, besides the significant factors of history of bone fracture and tobacco-smoking, asthma was also associated with edentulousness at an odds ratio of 10.81 (95% CI: 1.38-84.66), oldest subjects most often being edentulous (OR: 2.23, 95% CI: 1.13-4.39). Diabetes was not related to edentulousness either in the mandible or in the maxilla.

CONCLUSIONS

The finding of associations of history of bone fracture, tobacco-smoking, and asthma with edentulousness emphasizes the association of systemic conditions with edentulousness. Advanced age was related to an edentulous maxilla. The relationship between asthma and total tooth loss in the maxilla might suggest a local oral effect of medications used by asthmatic patients.

A monoclonal antibody to ICP4 of MDV recognizing ICP4 of serotype 1 and 3 MDV strains

Monoclonal antibodies (MAbs) were prepared against ICP4 of Marek's disease virus (MDV). Mice were inoculated with ICP4 obtained from High-Five insect cells infected with a recombinant baculovirus expressing ICP4. MAbs were selected by enzyme-linked immunosorbent assay (ELISA) using MDV-infected and control chick kidney cells as antigens. One of the MAbs, 5H8, recognized an epitope toward the carboxyl terminus of ICP4 based on staining of reticuloendotheliosis virus-transformed cells transfected with full-length and truncated ICP4 constructs. This MAb recognized ICP4 in chicken embryo fibroblasts (CEFs) infected with MDV strains JM16 and HVT but not with SB-1 strain. Using Western blot analysis a protein of 155 kDa was detected in CEFs infected with JM16 and HVT strains.

[Gene frequency of HPA among Hunan population of Han nationality]

We used allele specific primer PCR (ASP-PCR) method to detect the genotype of five major HPA systems among Hunan population of Han nationality. The results showed: The gene frequency of PLA1 was 81.00% and 85.87% for Kob, 71.00% for Baka, 91.00% for Pena, 90.67% for Brb which provided the basis for further clinical application of HPA.

The structural and functional analysis of the hemoglobin D component from chicken

Oxygen binding by chicken blood shows enhanced cooperativity at high levels of oxygen saturation. This implies that deoxy hemoglobin tetramers self-associate. The crystal structure of an R-state form of chicken hemoglobin D has been solved to 2.3-A resolution using molecular replacement phases derived from human oxyhemoglobin. The model consists of an alpha2 beta2 tetramer in the asymmetric unit and has been refined to a R-factor of 0.222 (R-free = 0.257) for 29,702 reflections between 10.0- and 2.3-A resolution. Chicken Hb D differs most from human oxyhemoglobin in the AB and GH corners of the alpha subunits and the EF corner of the beta subunits. Reanalysis of published oxygen binding data for chicken Hbs shows that both chicken Hb A and Hb D possess enhanced cooperativity in vitro when inositol hexaphosphate is present. The electrostatic surface potential for a calculated model of chicken deoxy-Hb D tetramers shows a pronounced hydrophobic patch that involves parts of the D and E helices of the beta subunits. This hydrophobic patch is a promising candidate for a tetramer-tetramer interface that could regulate oxygen binding via the distal histidine.

GRAB proteins, novel members of the NAC domain family, isolated by their interaction with a geminivirus protein

Geminiviruses encode a few proteins and depend on cellular factors to complete their replicative cycle. As a way to understand geminivirus-host interactions, we have searched for cellular proteins which interact with viral proteins. By using the yeast two-hybrid technology and the wheat dwarf geminivirus (WDV) RepA protein as a bait, we have isolated a family of proteins which we termed GRAB (for Geminivirus Rep A-binding). We report here the molecular characterization of two members, GRAB1 and GRAB2. We have found that the 37 C-terminal amino acids of RepA are required for interaction with GRAB proteins. This region contains residues conserved in an equivalent region of the RepA proteins encoded by other viruses of the WDV subgroup. The N-terminal domain of GRAB proteins is necessary and sufficient to interact with WDV RepA. GRAB proteins contain an unique acidic C-terminal domain while their N-terminal domain, of ca. 170 amino acids, are highly conserved in all of them. Interestingly, this conserved N-terminal domain of GRAB proteins exhibits a significant amino acid homology to the NAC domain present in proteins involved in plant development and senescence. GRAB1 and GRAB2 mRNAs are present in cultured cells and roots but are barely detectable in leaves. GRAB expression inhibits WDV DNA replication in cultured wheat cells. Our studies highlight the importance that the pathway(s) mediated by GRAB proteins, as well as by other NAC domain-containing proteins, might have on geminivirus DNA replication in connection to plant growth, development and senescence pathways.

[Optimum choice for the cultivation of CFU-GM in media buffered with HEPES]

The effects of media buffered with HEPES of different concentrations and different incubation periods on the proliferation and differentiation of CFU-GM were studied under the standard condition for culture. The results exhibited that when the incubation period prolonged, the pH values of culture system raised and the colony formation of CFU-GM decreased; the culture system added with proper HEPES buffer solution could maintain and increase the colony formation of CFU-GM, especially the culture system in which the pH value was not adjusted before the experiment. We also found that media buffered with HEPES could change the ratio of different colony types. This showed that media buffered with HEPES could not only stimulate the proliferation of CFU-GM, but also affect its differentiation. The results suggest that media buffered with HEPES are better than those without HEPES for the culture of hematopoietic progenitor cells, and the optimum concentration is 10-20 mmol.L-1.

Evaluation of pulmonary afferent fibers in the nucleus tractus solitarius: a horseradish peroxidase and c-fos like immunohistochemical study in the rat

Wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) was injected into the rat lung parenchyma, just beneath the lateral surface of the left upper lobe, in order to demonstrate the pulmonary afferents. This injection resulted in heavy accumulation of labeled fibers in the medial nucleus tractus solitarius (NTS). The labeling in the medial NTS was divided into the ventral and dorsal parts at the level around the obex. Some labeling was found in the commissural and ventrolateral NTS. Further confirmation of the central distribution of these pulmonary afferent fibers was made by the expression of fos-like immunoreactivity (FOS-LI) induced by injection of formalin into the lung. It is concluded that afferents of lung parenchyma terminating predominantly in the medial NTS might come from alveoli and terminal bronchioles, because WGA-HRP and formalin injected into the lung are considered to be confined to the terminal areas of the respiratory tract.

Synthesis and immunosuppressant activity of pyrazole carboxamides

A series of novel pyrazole carboxamides is disclosed that demonstrate strong immunosuppressant activity in rodent and human mixed leukocyte response (MLR) assays (IC50 < 1 microM). The synthesis, biological activity, mode of action, and pharmacokinetic properties of this new lead series are discussed.

Discovery of ascomycin analogs with potent topical but weak systemic activity for treatment of inflammatory skin diseases

Drug therapy for the major inflammatory skin diseases, which include atopic dermatitis, psoriasis and allergic contact dermatitis, is often inadequate due to poor efficacy, toxicity, or both. Much research has focused on the macrolactam T cell inhibitors as a promising new class of agents for immunotherapy, and medicinal chemistry efforts to design novel ascomycin analogs have produced clinically promising agents. A synthetic program to modify the ascomycin nucleus to alter its physicochemical properties and promote systemic clearance is described. A biologic screening strategy to identify analogs with reduced systemic activity and rapid pharmacokinetic elimination led to identification of the clinical candidate, ABT-281. A swine contact hypersensitivity model was used as a stringent indicator of skin penetration as human doses of topical corticosteroids produced inhibition only in the 50% range and ED50 values were 100-fold less potent than in rat. Also, cyclosporine was confirmed to be topically inactive in swine, as seen in human. ABT-281 had topical potency equal to tacrolimus (FK506) despite a severalfold lower potency for inhibiting swine T cells in vitro, consistent with superior skin penetration. ABT-281 was found to have a shorter duration of action after i.v. dosing in monkeys using an ex vivo whole blood IL-2 production assay. Systemic potency was reduced by 30-fold or more in rat popliteal lymph node hyperplasia and contact hypersensitivity assays. Following i.v. or i.p. administration in the swine contact hypersensitivity model, ABT-281 was 19- and 61-fold less potent, respectively, than FK506. Pharmacokinetic studies showed that ABT-281 had a shorter half life and higher rate of clearance than FK506 in all three species. The potent topical activity and reduced systemic exposure of ABT-281 may thus provide both efficacy and a greater margin of safety for topical therapy of skin diseases.

Occlusion of the femoral artery induced fos-like immunoreactive neurons in the lateral habenular nucleus projecting to the midbrain periaqueductal gray in the rat

Wheat germ agglutinin conjugated horseradish peroxidase (WGA-HRP) injection into the midbrain periaqueductal gray (PAG) resulted in heavy accumulation of retrogradely labeled neurons in the lateral habenular nucleus (LHb) bilaterally. When the left femoral artery was persistently ligated for 2 h, the expression of Fos-like immunoreactivity (FOS-LI) was also found bilaterally in the LHb. In the present study, by combining the retrograde labeling method of injecting WGA-HRP into the PAG and the immunohistochemical staining of the FOS-LI neurons in the LHb induced by occlusion of the femoral artery, it was demonstrated that there are neurons containing both HRP labeling and FOS-LI. These neurons appeared to be located mainly in the medial part and posterior half of the LHb, and constitute about 24% of the total number of all labeled cells.

Distribution of F4/80-positive cells in developing ovaries in the mouse

The mature ovary contains a large number of macrophages. In the present study, the distribution of macrophages in murine ovaries at various developmental stages was immunohistochemically studied using a monoclonal antibody against F4/80, a highly specific antigen of murine macrophages. The results showed that definite F4/80-positive stains were hardly detectable in ovaries on day 0 after birth. On day 7, a few F4/ 80-positive cells could be identified between the developing follicles. The positive stains were irregular in shape and showed little physical contact with the primordial or primary follicles. By days 14 and 21, when the theca cell layers of growing follicles were developing, the positive cells had extended or elongated to surround the cell layer. On day 28, besides the presence of elongating positive cells surrounding the growing follicles, irregularly shaped F4/80-positive cells became apparent in the interstitium between the growing follicles and also in the capsular tissues. Thereafter, positive cells with stellate appearance were detected in the corpora lutea, which first developed around 6 weeks of age. Although the positive cells were homogenously distributed in the corpora lutea in virgin adults, only a few sporadic positive cells were found there in pregnant mice. However, the positive cells infiltrated into the corpora lutea again in the postpartum period. These results show that ovarian macrophages exhibit dramatical changes in their distribution from neonatal to postpartum periods.

Brainstem projections of sensory fibers of the lung: a horseradish peroxidase and c-fos-like immunohistochemical study in the rat

The brainstem projections of sensory fibers of the lung were determined in the rat by using the horseradish peroxidase (HRP) and c-fos immunohistochemical methods. Wheat germ agglutinin conjugated HRP (WGA-HRP) was injected into the parenchyma of the upper lobe of the left lung. This injection resulted in anterograde labeling in the nucleus of the tractus solitarius (NTS), area postrema (AP) and external cuneate nucleus (ECu) with slightly ipsilateral predominance. It was of interest that these labeled sensory fibers are heavily accumulated in the medial subnucleus at the rostral pole of the NTS and in the commissural subnucleus at the caudal pole. In particular, labeled fibers in the medial subnucleus were characterized by division into the ventral and dorsal portions. After formalin was injected into the parenchyma of the upper lobe of the left lung, the expression of c-fos-like immunoreactivity (FOS-LI) was observed in three nuclei of the brainstem mentioned above. In addition, this experiment resulted in the expression in the ventrolateral medulla, nucleus raphe pallidus and dorsal motor nucleus of vagus nerve bilaterally. With respect to the number of the immunoreactive cells, we could draw the conclusion that the most optimum time to induce the expression of FOS-LI is between 1.5 h and 2.0 h after noxious stimuli.

Patterns of efferent lymphatics of the mouse testis

Previous studies in the rat demonstrated that lymph vessels arise from various sites in the testis and then anastomose to form the main lymph trunk toward the testicular artery. Although mice are as commonly used in the laboratory as the rat, precise knowledge concerning their testicular lymphatics has not been established. In the present study, the patterns of testicular lymphatic drainage in the mouse were examined using local injection of India ink into the testicular parenchyma. The results demonstrated that, besides the lymph trunk surrounding the testicular artery, a lymphatic drainage route running along the ductus deferens is also present.

Effects of age on the posttranscriptional regulation of CCAAT/enhancer binding protein alpha and CCAAT/enhancer binding protein beta isoform synthesis in control and LPS-treated livers

The CCAAT/enhancer binding protein alpha (C/EBPalpha) and CCAAT/enhancer binding protein beta (C/EBPbeta) mRNAs are templates for the differential translation of several isoforms. Immunoblotting detects C/EBPalphas with molecular masses of 42, 38, 30, and 20 kDa and C/EBPbetas of 35, 20, and approximately 8.5 kDa. The DNA-binding activities and pool levels of p42(C/EBPalpha) and p30(C/EBPalpha) in control nuclear extracts decrease significantly whereas the binding activity and protein levels of the 20-kDa isoforms increase dramatically with LPS treatment. Our studies suggest that the LPS response involves alternative translational initiation at specific in-frame AUGs, producing specific C/EBPalpha and C/EBPbeta isoform patterns. We propose that alternative translational initiation occurs by a leaky ribosomal scanning mechanism. We find that nuclear extracts from normal aged mouse livers have decreased p42(C/EBPalpha) levels and binding activity, whereas those of p20(C/EBPalpha) and p20(C/EBPbeta) are increased. However, translation of 42-kDa C/EBPalpha is not down-regulated on polysomes, suggesting that aging may affect its nuclear translocation. Furthermore, recovery of the C/EBPalpha- and C/EBPbeta-binding activities and pool levels from an LPS challenge is delayed significantly in aged mouse livers. Thus, aged livers have altered steady-state levels of C/EBPalpha and C/EBPbeta isoforms. This result suggests that normal aging liver exhibits characteristics of chronic stress and a severe inability to recover from an inflammatory challenge.

[Preliminary experiment on selection of oral hygienic cleanser]

The effectiveness of three commercial chewing gums ("Hua Aikang","Cao Shanhu" and "Poli") and brushing with toothpaste on the elimination of dental plaque was observed in 31 healthy males (aged 19-25 years). Before and after chewing or brushing, evaluation of oral taste and examination of plaque were performed. The result showed that the oral taste after chewing, "hua aikang" was the best, then "po li" and "cao shanhu"; plaque indexes were substantially reduced by all four kinds of treatment (P < 0.001) as compared with the pretest values, however "hua aikang" demonstrated a better effectiveness (P < 0.001). It also indicates that plaque index is an important index revealing the hygiene status.

The maize retinoblastoma protein homologue ZmRb-1 is regulated during leaf development and displays conserved interactions with G1/S regulators and plant cyclin D (CycD) proteins

Recent discoveries of plant retinoblastoma (Rb) protein homologues and D-type cyclins suggest that control of the onset of cell division in plants may have stronger parallels with mammalian G1/S controls than with yeasts. In mammals, the Rb protein interacts specifically with D-type cyclins and regulates cell proliferation by binding and inhibiting E2F transcription factors. However, the developmental role of Rb in plants and its potential interaction with cell cycle regulators is unknown. We show that the maize Rb homologue ZmRb-1 is temporally and spatially regulated during maize leaf development. ZmRb-1 is highly expressed in differentiating cells, but almost undetectable in proliferating cells. In vitro, both ZmRb-1 and human Rb bind all classes of plant D-type cyclins with the involvement of a conserved N-terminal Leu-x-Cys-x-Glu (LxCxE) Rb-interaction motif. This binding is strongly reduced by mutation of the conserved Cys-470 of ZmRb-1. ZmRb-1 binds human and Drosophila E2F, and inhibits transcriptional activation of human E2F. We also show that ZmRb-1 is a good in vitro substrate for all human G1/S protein kinases. The functional conservation of proteins that control the G1/S transition in mammals and plants points to the existence of plant E2F homologues. We conclude that evolution of Rb and cyclin D proteins occurred after separation of the fungi from the higher eukaryotic lineage, but preceded the divergence of plant and animal kingdoms.

Postnatal development of Leydig cells in the opossum (Monodelphis domestica): an immunocytochemical and endocrinological study

This study involved characterization of Leydig cells of the opossum Monodelphis domestica, functionally by immunocytochemical identification of the enzyme 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) and by measurement of testosterone levels using RIA. Immunostaining for 3 beta-HSD was first detected in a few Leydig cells on Day 16, was increased by Day 24, reached a peak at 4 mo, and was present even in senescent (3 yr) animals. Plasma testosterone was first measurable (0.35 nM) at prepuberty (3.5 mo). Prior to that, plasma testosterone concentrations were uniformly below the level of detection (< 0.3 nM) in both sexes from Day 5 to 2.5 mo. By 4 mo (puberty), plasma testosterone levels in males had risen significantly to 1.53 +/- 0.35 nM, continuing to increase to 1.79 +/- 0.4 nM at 6 mo and peaking at 2.71 +/- 0.29 nM in the adult (1-2 yr). Ovarian testosterone concentrations were consistently lower than those in the testis, as were those of adrenals of both sexes. Thus the testis would appear to be the major source of androgen production throughout life in this species. Our immunocytochemical study suggests that in Monodelphis, puberty is reached at 4 mo, and this was further supported by a rise in circulating testosterone levels at this time.

Essential pathogenic role for endogenous interferon-gamma (IFN-gamma) during disease onset phase of murine experimental autoimmune orchitis. I. In vivo studies

We previously found that immunization of CH3/He male mice with syngeneic testicular germ cells (TGC) without the aid of any adjuvants was sufficient to induce DTH to TGC and experimental autoimmune orchitis (EAO). To evaluate the role of endogenous IFN-gamma in this model, C3H/He mice immunized subcutaneously with TGC on days 0 and 14 received a single injection of anti-murine IFN-gamma MoAb on day 15, 20 or 25. On day 45, DTH to TGC was tested, testis specimens were collected for histological examination, and blood samples collected for IFN-gamma measurement. The results showed that whilst MoAb treatment on day 15 or 25 did not influence DTH responses, EAO development, and appearance of IFN-gamma in the circulation, treatment on day 20 significantly suppressed all of them. Thus, a single injection with anti-IFN-gamma MoAb may successfully down-regulate testicular autoimmunity, provided that the treatment is given at an optimal time point during disease development.

Estimation of the numerical densities of neurons and synapses in cerebral cortex

In this paper we discuss a stereological technique, 'the unfolding method', for a quantitative study of the nervous system [1,31]. Stereology implies a geometric analysis of structures and textures, and is a method to derive directly metric properties of structures from two-dimensional sections on the basis of geometrico-statistical reasoning [36,37]. Recent advances in the stereological method allow quantitative analysis [8,19,27,32]. Images on sections provide only two-dimensional information, but the stereological method can offer three-dimensional and quantitative information [19]. The need for quantitative analysis is more important and useful in the central nervous system (CNS) than in other organs. Two functional units, neurons and synapses, are of particular interest in evaluating CNS function. Numerical densities of neurons and synapses in rat visual cortex were estimated using the unfolding method at light and electron microscopic levels, respectively. Once the numerical densities of neurons and synapses were obtained, synapse-to-neuron ratios could be calculated. The ratios are interpreted as a means to obtain an index of interneuronal connectivity [9]. The unfolding method may become a powerful strategy in neuroscience research when numerical estimates are performed in restricted areas such as cortical layers II-IV, because this method is less time-consuming than other stereological methods [6,21,22].

A novel antioxidant gene from Mycobacterium tuberculosis

Among the major antimicrobial products of macrophages are reactive intermediates of the oxidation of nitrogen (RNI) and the reduction of oxygen (ROI). Selection of recombinants in acidified nitrite led to the cloning of a novel gene, noxR1, from a pathogenic clinical isolate of Mycobacterium tuberculosis. Expression of noxR1 conferred upon Escherichia coli and Mycobacterium smegmatis enhanced ability to resist RNI and ROI, whether the bacteria were exposed to exogenous compounds in medium or to endogenous products in macrophages. These studies provide the first identification of an RNI resistance mechanism in mycobacteria, point to a new mechanism for resistance to ROI, and raise the possibility that inhibition of the noxR1 pathway might enhance the ability of macrophages to control tuberculosis.

Different susceptibility of three clinically isolated strains of Cryptococcus neoformans to the fungicidal effects of reactive nitrogen and oxygen intermediates: possible relationships with virulence

We investigated the susceptibility of three clinically isolated strains of Cryptococcus neoformans with different virulences to reactive nitrogen and oxygen intermediates (RNI and ROI, respectively), representing two important mediators of macrophage microbicidal activity. All mice infected with the highly virulent strain of C. neoformans, YC-11, died within 3 to 6 weeks because of rapid multiplication of the organism in the lungs and dissemination to the brain. In contrast, a weakly virulent strain, YC-13, was almost completely eradicated from the lungs and did not disseminate to the brain, leading to survival of all infected animals during the period of observation (15 weeks). The virulence of the third strain, YC-5, was intermediate between the other two strains. To examine the susceptibility of C. neoformans to the fungicidal effect of nitric oxide (NO) and superoxide anions (O2-), the organisms were exposed to these oxidants, which were chemically generated in a cell-free system. Interestingly, the number of live YC-13 yeast cells was markedly reduced after exposure to NO and O2-. In contrast, YC-11 was almost completely resistant to the killing effect of these oxidants. YC-5 showed an intermediate susceptibility. Our results demonstrate that the resistance of C. neoformans to the fungicidal effects of RNI and ROI is related to virulence, and suggest that the resistance to nitrogen- and oxygen-derived oxidants may be one of the factors to determine the outcome of infection with C. neoformans.

Association of residual ridge resorption with systemic factors in home-living elderly subjects

Residual ridge resorption after loss of teeth is a multifactorial oral problem. To examine the association of residual ridge resorption with systemic factors, a cross-sectional study was made of 177 edentulous subjects (43 men and 134 women) aged 76, 81, and 86 years. Resorption in the mandibular and maxillary residual ridges was assessed from panoramic radiographs. The effects on residual ridge resorption of the age, gender, smoking, alcohol intake, body mass index, functioning in daily living, and certain systemic diseases of the subjects were investigated. After adjustment for age and duration of edentulousness, the elderly women had a greater amount of reduction in the mandibular residual ridge than the men (P < 0.001). When the resorption was classified into slight or moderate and severe resorptions, the elderly with asthma were at high risk of severe reduction in the edentulous mandible (odds ratio, 6.0; 95% confidence interval (CI), 1.3-28.2); the elderly women were at high risk of severe resorption in the edentulous mandible, with an odds ratio of 4.5 (95% CI, 1.2-17.1); an inverse association was found between alcohol intake and severe resorption in the edentulous maxilla (odds ratio, 0.4; 95% CI, 0.2-0.9). This study suggests that asthma due to corticosteroid treatment is to be considered a risk indicator for severe resorption of the edentulous mandible, alcohol intake in the elderly may be related to a lesser degree of resorption of the edentulous maxilla. Female gender is confirmed as a major factor resulting in mandibular atrophy.

Oral status and prosthetic factors related to residual ridge resorption in elderly subjects

Our earlier studies on edentulous elderly subjects have shown associations of severe resorption in the mandibular residual ridge with female gender and systemic diseases. The aim of this study was to examine whether other factors also were related to residual ridge resorption (RRR). Among 177 edentulous elderly subjects effects on RRR were investigated with regard to history of edentulousness and denture-wearing, the condition of the dentures and soft tissues, dental status of the opposing jaw, and oral hygiene habits. No significant association was found between degree of resorption and duration of edentulousness in either the mandible or the maxilla. RRR was related to denture quality (P < 0.05); however, severe resorption was not. In the maxilla previous use of removable partial dentures was a factor contributing to the resorption (odds ratio (OR), 2.4); flabby ridge was related to the severity of the resorption (OR, 2.4). This study showed local factors related to RRR more often in the maxilla than in the mandible, thus suggesting that severe resorption in the mandible is influenced more by systemic factors than by those investigated in this study.

A novel lipopolysaccharide-response element contributes to induction of nitric oxide synthase

The gene encoding the high output isoform of nitric oxide synthase represents a large class of alarm and defense genes transcriptionally induced in response to bacterial lipopolysaccharide (LPS). The promoters of most of these genes contain at least two LPS-response elements, one of which commonly binds transcription factors of the NF-kappaB/Rel family. Here a novel LPS-response element is identified in the inducible nitric oxide synthase promoter, termed LREAA, which contains critical adenosine residues lying 19-20 base pairs downstream of the proximal NF-kappaB binding element (NFkappaBd). Both NFkappaBd and LREAA are required for LPS-induced promoter activity. A protein partially recognized by antibody against transcription factor Oct-1 binds to the LREAA element constitutively in untreated macrophages while contributing to a DNA-protein complex that includes NF-kappaB p50 in macrophages treated with LPS. NF-kappaB p50 and the LREAA-binding proteins may together recruit an LPS-triggered transactivator of transcription.

Resorption of mandibular canal wall in the edentulous aged population

STATEMENT OF PROBLEM

The mandibular canal wall may be affected by the progress of residual ridge resorption after tooth extraction. Little knowledge is available regarding the relationship of specific systemic factors and the resorption of the mandibular canal wall.

PURPOSE

The purpose of this study was to assess the status of the mandibular canal in the edentulous mandible and to determine whether there is any relationship between the resorption of the mandibular canal wall and selected health indices in the elderly.

MATERIAL AND METHODS

The status of the mandibular canal was assessed from panoramic radiographs of 128 edentulous elderly subjects (32 men and 96 women).

RESULTS

The superior border of the mandibular canal was more frequently resorbed in women (32.6%) than in men (9.8%). Resorption in the mandibular canal wall was significantly more prevalent in subjects with asthma (odds ratio: 6.0), with thyroid disease (odds ratio: 3.04), and with a cortical thickness at the mandibular angle less than 1 mm thick (odds ratio 2.74).

CONCLUSION

The findings suggest that gender, asthma, and thyroid disease play important roles in resorption of the mandibular canal wall.

[Antiallergic effects of tranilast in rats and guinea pigs]

Tranilast is an anti-allergic drug. In this study, we made a comparision between the Tranilast synthized by School of Pharmacy WCUMS using new technical and the Tranilast produced by Kissei pharmaceutical Co. LTD, Japan on their antiallergic effects. We found that the two tranilasts had the same antiallergic effects: (1) they inhibit the passive cutaneous anaphylaxis in sensitized rats with the dose of 100, 200 mg/kg(P < 0.01); (2) they inhibit degranulation of mast cells in sensitized rats (10(-5) and 10(-4) mol/L) (P < 0.05); (3) they inhibit schultz-Dale response in sensitized guinea pigs (10(-3) and 10(-4) (mol/L); (4) the inhibit SRS-A release from the lung of sensitized guinea pigs(10(-3), 10(-4) and 10(-5) mol/L) (P < 0.05); and (5) they inhibit the contraction of ileum of normal guinea pigs induced by SRS-A(10(-4) and 10(-3) mol/L).

Quantitative assessment of vertical heights of maxillary and mandibular bones in panoramic radiographs of elderly dentate and edentulous subjects

The clinical applicability of vertical measurements of the mandible and maxilla in panoramic radiographs was studied by assessing the variety of vertical heights among 91 elderly dentate subjects. Measurements in each jaw and calculations of a maxillary ratio were made at five sites. Variations in measurements of the dentate subjects were small: 9-11% for vertical measurements in the mandible, 6-11% for vertical measurements in the maxilla, and 8-10% for the maxillary ratios. These findings suggest that it is possible quantitatively to assess heights of the mandibular and maxillary bones in panoramic radiographs. Reductions in the edentulous jaws were assessed by comparing the heights of jaws of elderly dentate subjects with those measured in 177 elderly edentulous subjects. Significant differences in heights of the mandibular body and maxilla were found between the dentate and the edentulous (P < 0.001). Edentulous women had greater values for percentage reduction in the mandibles than did the men (P < 0.01; P < 0.001 in various locations).

Central distribution of sensory fibers in the facial nerve: an anatomical and immunohistochemical study

Wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) injection into the facial nerve of the cat resulted in retrograde labeling in the geniculate and jugular ganglia ipsilaterally. Labeled fibers were found to enter into the brain stem through the intermediate and vagal nerves. These fibers ascended or descended into the dorsal portion of the spinal trigeminal tract and were distributed to the principal sensory nucleus of the trigeminal nerve, marginal layer of the interpolar part of the spinal trigeminal nucleus, nucleus of the solitary tract and ventrolateral portion of the cuneate nucleus. It was of particular interest in the present study that the intensive labeling was present in the medial portion of laminae I-IV of the upper cervical spinal cord. The immunohistochemical study revealed a lot of substance P-immunoreactive neurons in the geniculate and jugular ganglia, and heavy accumulation of immunoreactive fibers in laminae I-II of the upper cervical spinal cord.

Expression and phosphorylation of a MARCKS-like protein in gastric chief cells: further evidence for modulation of pepsinogen secretion by interaction of Ca2+/calmodulin with protein kinase C

In gastric chief cells, agents that activate protein kinase C (PKC) stimulate pepsinogen secretion and phosphorylation of an acidic 72-kDa protein. The isoelectric point and molecular mass of this protein are similar to those for a common PKC substrate; the MARCKS (for Myristoylated Alanine-Rich C Kinase Substrate) protein. We examined expression and phosphorylation of the MARCKS-like protein in a nearly homogeneous suspension of chief cells from guinea pig stomach. Western blotting of fractions from chief cell lysates with a specific MARCKS antibody resulted in staining of a myristoylated 72-kDA protein (pp72), associated predominantly with the membrane fraction. Using permeabilized chief cells, we examined the effect of PKC activation (with the phorbol ester PMA), in the presence of basal (100 nM) or elevated cellular calcium (1 microM), on pepsinogen secretion and phosphorylation of the 72-KDa MARCKS-like protein. Secretion was increased 2.3-, 2.6-, and 4.5-fold by incubation with 100 nM PMA, 1 microM calcium, and PMA plus calcium, respectively. A PKC inhibitor (1 microM CGP 41 251) abolished PMA-induced secretion, but did not alter calcium-induced secretion. This indicates that calcium-induced secretion is independent of PKC activation. Chief cell proteins were labeled with 32P-orthophosphate and phosphorylation of pp72 was detected by autoradiography of 2-dimensional polyacrylamide gels. In the presence of basal calcium, PMA (100 nM) caused a > two-fold increase in phosphorylation of pp72. Without PMA, calcium did not alter phosphorylation of pp72. However, 1 microM calcium caused an approx. 50% attenuation of PMA-induced phosphorylation of pp72. Experiments with a MARCKS "phosphorylation/calmodulin binding domain peptide" indicated that calcium/calmodulin inhibits phosphorylation of pp72 by binding to the phosphorylation/calmodulin binding domain and not by inhibiting PKC activity. These observations support the hypothesis that, in gastric chief cells, interplay between calcium/calmodulin binding and phosphorylation of a common domain on the 72-kDa MARCKS-like protein plays a role in modulating pepsinogen secretion.

Structure of chain d of the gigantic hemoglobin of the earthworm

The extracellular hemoglobin of the earthworm has four major O2-binding chains, a, b, c and d, together with additional non-heme structural chains that are required for assembly. Although the abc trimer self-associates extensively at least to (abc)10, addition of chain d results in the formation of a discrete 280 kDa complex corresponding to (abcd)4. Thus a primary function of chain d is to cap the abc association and convert an abc trimer that binds O2 with weak cooperativity to a highly cooperative (abcd)4 complex. Amino-acid sequences of the major globin chains a, b, c have been determined previously by peptide and cDNA analysis. However, the peptide sequence reported for the major chain d (Shishikura, F., Snow, J.W., Gotoh, T., Vinogradov, S.N. and Walz, D.A. (1987) J. Biol. Chem., 262. 3123-3131), has a calculated molecular mass 134-167 Da higher than masses for components of chain d determined by mass spectrometry (Owrby, D.W., Zhu, H., Schneider, K., Beavis, R.C., Chait, B.T. and Riggs, A.F. (1993) J. Biol. Chem. 268, 13539-13547). Reverse-phase HPLC confirms the presence of two distinct polypeptides, d1 and d2, together with d'1, a variant of d1, cDNA derived amino acid sequences have been determined for chains d'1 and d2 by application of the polymerase chain reaction with primers based on the NH2-terminal sequences and oligo-dT. Each of the two cDNA-derived sequences has 140 residues and they differ by 28 substitutions. The data show that the sequence originally reported had been derived from peptides generated from both polypeptides.

[Expression level of MDR1, and MRP in patients with malignant blood disease and its clinical significance]

RT-PCR method was used to detect the expression level of multi-drug resistance gene (MDR1) and multi-drug resistance associated protein (MRP) in patients with malignant blood disease, including 19 cases of acute leukemia and 6 cases of multiple myeloma. The results showed: expression level of MDR1 in patients with known clinical drug resistance elevated obviously and was significantly associated with clinical drug resistance (r = 0.612, P < 0.01), which indicated that expression of MDR1 was the main mechanism of clinical drug resistance. There is no obvious relationship between expression level of MDR1 and MRP (r = 0.035, P > 0.05).

Assessment of the effect of an oscillating/rotating electric toothbrush on oral health. A 12-month longitudinal study

The aim of this 12-month parallel design controlled clinical trial was to assess the effect of the Braun Oral-B Plak Control electric toothbrush on supragingival plaque and gingival health, and to compare it with a conventional soft manual toothbrush (Jordan). A total of 111 patients aged between 20 and 63 years, from a general population, with bleeding on probing at 30% or more of all sites examined were entered into the study. At baseline, immediately after periodontal examination, all volunteers received a thorough scaling of their teeth. Volunteers in both groups were told to brush their teeth for 2 min 2 x a day. Oral hygiene instruction was given at the start of the study and was not repeated. At 3, 6 and 12 months, assessments were carried out by a single clinician who was not aware which group the volunteers belonged to. Analysis of results demonstrated that over the 12 months of the study, the Braun Oral-B Plak Control was significantly more effective in improving gingival health than the manual toothbrush. There was, however, no difference between the 2 groups in terms of plaque removal, with the number of sites with visible plaque decreasing by a similar amount in both groups. In conclusion, results indicate that the Braun Oral-B Plak Control toothbrush is safe and more effective than a manual toothbrush in improving gingival health.

Canine parvovirus capsid structure, analyzed at 2.9 A resolution

The DNA-containing capsid of canine parvovirus (CPV) is analyzed following atomic refinement at 2.9 A resolution. The capsid contains 60 copies of the capsid protein related by icosahedral symmetry. The atomic model has been extended from the first residue (Gly37) of the unrefined 3.25 A structure towards the N terminus. The electron density shows that approximately 87% of the capsid proteins have N termini on the inside of the capsid, but for approximately 13%, the polypeptide starts on the outside and runs through one of the pores surrounding each 5-fold axis, explaining apparently conflicting antigenic data. Analysis of potential hydrogen bonds reveals approximately 50% more secondary structure than previously apparent. Most of the additional secondary structure are in the 71 and 221 residue-long loop insertions between beta-strands E and F and G and H, forming subunit-bridging sheets that likely add specificity to assembly interactions. Structural analysis of the extensive subunit interactions around the 3-fold axes shows that assembly is a multistep process with loops intertwining following initial contact. Estimated free energies of association suggest that the formation of 3 and 5-fold contacts likely takes precedence over 2-fold interactions. Energies for initial association into trimers or pentamers would be similar, but the intertwining of loops about the 3-fold axis adds an additional large activation barrier to dissociation. Analysis of the surfaces of the assembled capsid shows a surprising lack of basic amino acids that might have been expected to interact with the negatively charged phosphoribose backbone of the DNA. Instead, uncharged polar and van der Waal's interactions predominate in the packaging of single-stranded DNA into the capsid.

Height of mandibular basal bone in dentate and edentulous subjects

Age-related differences in the height of the mandibular basal bone were compared between young and old dentate subjects and between dentate and old edentulous subjects by means of panoramic radiographs. The distances of the mental foramen and mandibular canal from the lower border of the mandible, when measured, showed the mandibular basal bones in old dentate and in old edentulous men to be higher than those of young dentate men in the molar region (P < 0.05). The height of the basal bone below the mental foramen was smaller in old edentulous women than in young and old dentate women (P < 0.05). A slight bone deposition along the lower border of the mandible in the molar region seems to take place with increasing age. The mental foramina of edentulous women move toward the lower border of the mandible as a result of alveolar bone resorption.

Stoichiometry of subunits and heme content of hemoglobin from the earthworm Lumbricus terrestris

The extracellular hemoglobin (Hb) of the earthworm, Lumbricus terrestris, has four major O2-binding chains, a, b, c (forming a disulfide-linked trimer), and d ("monomer"). Additional structural chains, "linkers," are required for the assembly of the approximately 200-polypeptide molecule. The proportion of linker chains had been reported to be one-third of the total mass on the basis of densitometry of Coomassie Blue-stained SDS-gels. Reverse-phase high performance liquid chromatography (HPLC), however, gave 16.3% linkers on the basis of both 220-nm absorbance and amino acid analysis (Ownby, D. W., Zhu, H., Schneider, K., Beavis, R. C., Chait, B. C., and Riggs, A. F. (1993) J. Biol. Chem. 268, 13539-13547). The subunit proportions have now been redetermined by SDS capillary electrophoresis as a test of the HPLC results. The electrophoresis, monitored at 214 nm, avoided the use of Coomassie Blue and provided results identical with those obtained by HPLC. Capillary electrophoresis monitored at both 214 and 415 nm was used to show that linker chains do not bind heme. Heme content has been found to be 2.9% by determination of hemin, amino acid analysis and dry weight. Measurement of the rate of hemin loss from oxidized L. terrestris Hb shows that high rates of loss can account for values of heme content significantly below 2.9% (or 0.26% iron).

Testis development in the opossum Monodelphis domestica

Testis development in the grey short-tailed opossum, Monodelphis domestica, was investigated by light and electron microscopy in 180 animals. On the day of birth, half the karyotyped males were found to have histologically differentiated testes. By day (d) 1 testicular cords were clearly distinguished in all XY gonads and the tunica albuginea was fully developed. At this stage the large and pale primordial germ cells could be differentiated from dark pre-Sertoli cells. From d 3 the testis became progressively rounded and testicular cords were surrounded by peritubular cells. Leydig cells were then distinguishable by the expected ultrastructural features of steroidogenically active cells, showing abundant vesicles of SER, extensive mitochondria with tubular cristae and numerous lipid inclusions. Subsequently these cells formed clusters and were surrounded by envelope cells until wk 12. Testes were located in the abdomen, attached to the large mesonephroi, until d 24 after birth when they began their descent to the scrotal sac. From 7 wk the interstitial tissue became less cellular. At the prepubertal stage (12 wk), the seminiferous tubules lacked lumina. Leydig cell cytoplasm was electron-dense with increased amounts of SER forming parallel profiles. By 4 mo (pubertal stage), seminiferous tubules were patent and various spermatogenic stages, including spermatozoa, were seen for the first time. Leydig cells then greatly outnumbered other interstitial tissue cells and were closely-packed around blood vessels but no longer clustered by envelope cells; their SER was very highly organised into masses of parallel arrays and lipid inclusions were reduced. In the adult (1 y) Leydig cells reached their greatest size; their morphological features resembled those seen at 4 mo except that lipid inclusions were sparse. In ageing Leydig cells (2-3 y), large amounts of SER were present but disorganised.