Measurement of strain in physical models of brain injury: a method based on HARP analysis of tagged magnetic resonance images (MRI)

Two-dimensional (2-D) strain fields were estimated non-invasively in two simple experimental models of closed-head brain injury. In the first experimental model, shear deformation of a gel was induced by angular acceleration of its spherical container In the second model the brain of a euthanized rat pup was deformed by indentation of its skull. Tagged magnetic resonance images (MRI) were obtained by gated image acquisition during repeated motion. Harmonic phase (HARP) images corresponding to the spectral peaks of the original tagged MRI were obtained, following procedures proposed by Osman, McVeigh and Prince. Two methods of HARP strain analysis were applied, one based on the displacement of tag line intersections, and the other based on the gradient of harmonic phase. Strain analysis procedures were also validated on simulated images of deformed grids. Results show that it is possible to visualize deformation and to quantify strain efficiently in animal models of closed head injury.

Cloning and sequence analysis of dsRNA segments 5, 6 and 7 of a novel non-group A, B, C adult rotavirus that caused an outbreak of gastroenteritis in China

A diarrhoeal outbreak among adults in China was caused by a new rotavirus, termed ADRV-N, that does not react with antisera directed against group A, B or C rotaviruses [Zhonghua Liu Xing Bing Xue Za Zhi (Chin. Epidemiol.) 19 (1998) 336]. ADRV-N can be propagated in cell cultures [Zhonghua Yi Xue Za Zhi (Natl. Med. J. China) 82 (2002) 14]. We present the complete sequences for ADRV-N genome segments 5 and 6, and a full ORF sequence of genome segment 7. The deduced amino acid sequences suggest that these segments encode NSP1, VP6 and NSP3, respectively. These three ADRV-N genome segments have a unique -ACCCC-3' terminal sequence. The 5'-GG- terminus of segments 5 and 6 is the same as that of other rotaviruses. The amino acid similarity between VP6 and NSP3 of ADRV-N and the cognate sequences of their closest counterpart, group B IDIR, was 37 and 35%, respectively. The ADRV-N NSP1 has a double-stranded RNA binding motif (DSRM) and a putative autoproteolytic cleavage motif upstream from the DSRM. The putative ADRV-N NSP3 has a truncated C-terminus compared to the cognate protein of group B rotaviruses. All the available data demonstrate that ADRV-N differs significantly from the known rotaviruses and strongly suggest that ADRV-N is the first recognized member of a new group of rotaviruses infecting humans.

Mechanisms of signal transduction mediated by oxidized lipids: the role of the electrophile-responsive proteome

Cellular redox signalling is mediated by the post-translational modification of proteins by reactive oxygen/nitrogen species or the products derived from their reactions. In the case of oxidized lipids, several receptor-dependent and -independent mechanisms are now emerging. At low concentrations, adaptation to oxidative stress in the vasculature appears to be mediated by induction of antioxidant defences, including the synthesis of the intracellular antioxidant glutathione. At high concentrations apoptosis occurs through mechanisms that have yet to be defined in detail. Recent studies have revealed a mechanism through which electrophilic lipids, formed as the reaction products of oxidation, orchestrate these adaptive responses in the vasculature. Using a proteomics approach, we have identified a subset of proteins in cells that we term the electrophile-responsive proteome. Electrophilic modification of thiol groups in these proteins can initiate cell signalling events through the transcriptional activation of genes regulated by consensus sequences for the antioxidant response element found in their promoter regions. The insights gained from our understanding of the biology of these mechanisms will be discussed in the context of cardiovascular disease.

Interference of magnetic and anisotropic tensor susceptibility reflections in resonant X-ray scattering of GdB4

Resonant x-ray scattering experiments at the Gd L3 edge show interference between magnetic and anisotropic tensor susceptibility (ATS) reflections in GdB4. Energy profiles obtained from the magnetic and ATS resonances exhibited approximately 10 eV separation between the maximum resonance energies. The findings show that the Gd 5d band experienced hybridization giving rise to a significant split into isotropic lower energy band and distorted upper band states that account for the magnetic and ATS scattering, respectively.

Selective denervation and resection of cervical muscles in the treatment of spasmodic torticollis: long-term follow-up results in 207 cases

OBJECT

To report the outcome of patients with selective denervation and resection of cervical muscles for spasmodic torticollis.

METHODS

We reviewed 362 cases of surgically treated spasmodic torticollis. 207 patients were followed from 2 years to 29 years.

RESULTS

Total or marked relief of symptoms with preservation of normal of nearly normal movements has been obtained in 87.9%.

CONCLUSION

This procedure may be recommended if one to two years of conservative therapy does not offer satisfactory relief of symptoms.

[Administration of leukemic granulocyte colony-stimulating factor to donors: the changes in donor bone marrow cell composition and the transplantation outcome]

OBJECTIVE

To investigate the change of bone marrow cell composition the effect of graft on hemopoietic reconstitution and the incidence of acute graft-versus-host disease (aGVHD) with granulocyte colony-stimulating factor G-CSF administration to donors before marrow harvesting.

METHODS

Twenty-four patients with myeloid leukemia underwent allogeneic bone marrow transplantation. The donors of twelve patients (study group) were given G-CSF 250 microg/d for seven days prior to harvesting. The marrow cell composition, the outcome of subsequent engraftment and the occurrence of aGVHD were compared with those in twelve patients without G-CSF (control group).

RESULTS

The bone marrow stimulated by G-CSF yielded higher number of nucleated cells, CD34+ cells, CFU-GM and CFU-MK (P < 0.01). The number of T lymphocyte subsets in the graft stimulated with G-CSF was different from that in the control group. The number of CD4+ cells was decreased and that of CD8+ increased. The CD4+/CD8+ ratio was reduced markedly (P < 0.01). The change of CD34+, CD4+, CD8+ percentage and CFU-GM, CFU-MK proliferation in donor bone marrow with and without G-CSF was compared. The same characteristic change as above graft was observed. Hemopoietic reconstitution in the study group after allo-BMT was accelerated. In the study group the days of granulocyte count exceeding 0.5 x 10(9)/L and platelet count exceeding 20 x 10(9)/L were 16 days (range 11 - 23 days) and 17 days (range 14 - 25 days) (in the control group 20.5 day, range 14 - 29 days and 23 days, range 17 - 32 days P < 0.05). Grade II - IV aGVHD did not occur in patients of the study group but in 3 patients of the control group.

CONCLUSION

The bone marrow harvested from donor with G-CSF stimulation can accelerate hemopoietic recovery and decrease the incidence of severe aGVHD. The accelerated hematopoietic recovery is associated with increased number of CD34+, CFU-GM and CFU-MK in the graft.

[A clinical study of haploidentical transplantation using granulocyte colony-stimulating factor stimulating donor bone marrow]

OBJECTIVE

To explore the effects of reducing the incidence of severe acute graft-versus-host disease (GVHD) and improving the disease free survival(DFS) in haploidentical donor transplantation by granlocyte colony-stimulating factor (G-CSF) administration to donor before harvesting and a number of immunosuppresants added to host.

METHODS

Thirteen patients with leukemia received allo-bone marrow transplantation (BMT) from two or three HLA loci mismatched related donor (haploidentical group). The clinical outcomes of the bone marrow transplantion were compared with thase of 13 consecutive HLA identical sibling transplantion (identical group). In haploidentical donor BMT, the donors of patients were given G-CSF (Lenograstim Chugai) 250 micrograms/day for seven doses prior to marrow harvest. CSA, MTX, ATG and mycophenolate mofetil (MMF) were combined for GVHD prophylaxis. ATG 5 mg/kg/day was infused for 4 days before transplantation and MMF was adminisered from 7th day after.

RESULTS

All the patients were engrafted. The median number of CD34+ cells in graft was 6.1 x 10(6)/kg in haploidentical group and 2.5 x 10(6)/kg in identical group (P < 0.01). The median number of CD3+ cells was 50.5 x 10(6)/kg and 47.0 x 10(6)/kg respectively (P > 0.05). All patients had 100% donors hematopoietic cells after transplantation by cytogenetic evidence analysis. Five of the thirteen patients (38.5%) in haploidentical group and three of the thirteen patients(23.1%) in identical group experienced II-IV acute GVHD (P > 0.05). The probability of chronic GVHD was 87.5% in haploidentical group and 67.5% in identical group (P > 0.05), However none in both groups developed extensive cGVHD. The median follow-up duration was 453 days (range 180-690 days) for haploidentical group and 510 days (range 220-810 days) for identical group. In haploidentical group, five patients died from transplant related mortality (3 GVHD, 2 infection), none relapsed and eight patients(61.5%) survive in disease free situation. In identical group, two patients died from transplant related mortality (1 GVHD, 1 infection), two patients died from relapse and nine patients (69.2%) survive in disease free situation. DFS in haploidentical group and in identical group was similar(P > 0.05).

CONCLUSION

The transplants from haploidentical donor used in this study is 3 effective and feasible in preventing acute severe GVHD and improving DFS.

[Preliminary study of HLA haplotype matched and T-cell undepleted allogeneic bone marrow transplantation for treatment of leukemia]

OBJECTIVE

To explore the feasibility of allogeneic bone marrow transplantation (Allo-BMT) with graft from HLA haplotype matched related donor without T-cell depleted for the treatment of leukemia.

METHODS

Fifteen patients with leukemia received allo-BMT with grafts from HLA 2 or 3 antigen mismatched related donors. All patients were treated with standardized conditioning regimen consisting of high dose Ara-C, cyclophosphamide (CY) and total body irradiation (TBI). Donors were given G-CSF at 3 to 4 micrograms.kg-1.d-1 for seven days prior to marrow harvest. GVHD prophylaxis programme consisted of CsA, MTX, ATG and mycophenolate mofetial.

RESULTS

All patients established successful engraftment. The median days of granulocyte > 0.5 x 10(9)/L and platelet > 20 x 10(9)/L were 19(range 13-23) and 21 (range 16-32) days, respectively. Acute grade II-IV GVHD occurred in 5 of 15 patients (33.3%). Two of them were grade II gut aGVHD, 2 grade III gut aGVHD, and 1 grade IV gut and liver aGVHD. Chronic GVHDs were seen in 8 of 9 evaluable patients (88.9%) and none developed extensive cGVHD. The median follow-up duration was 395 (110-690) days. Six of fifteen patients died. Five of them died from transplantation related mortality and 1 from relapse. Nine patients were alive in a disease-free situation. Six of them survived more than one year.

CONCLUSION

The major histoincompatibility barriers in the haplotype matched related donor/recipient allo-BMT might be crossed by donor stimulated with G-CSF and combined GVHD prophylaxis program.

The regulatory effect of ERK1/2 signal pathway on production of TNFalpha induced by LPS in mice Kupffer cells

OBJECTIVE

To study the rule of ERK1/2 activity and regulative effect of ERK1/2 pathway on the production of pro-inflammatory cytokine TNFalpha in mice Kupffer cells (mKC) induced by LPS, and to exploring novel methods to prevent and treat clinical patients of endotoxemia.

METHODS

Immunoprecipitate kinase assay and Western blotting analysis were used to detect the phosphorylated ERK1/2 kinase activity in mKC stimulated by LPS, and ELISA was used to study the effect of ERK1/2 signaling cascade on LPS-induced TNFalpha production in mKC.

RESULTS

In mKC, LPS treatment resulted in transient and rapid increase of kinase activity of ERK1/2 that phosphorylated their specific substrate ELK-1, with maximal value at 30 minutes and a return near to baseline within 2 hours, and LPS-induced ERK1/2 activity from LPS concentration of 10 pg/ml to the top activity at 100 ng/ml. No activity was observed in unstimulated mKC. Inhibition of the ERK1/2 pathway using the specific ERK1/2 signal pathway inhibitor PD98059 caused a marked and concentration-dependent reduction of TNFalpha production.

CONCLUSIONS

The results show that LPS can markedly activate ERK1/2 pathway in mKC. PD98059 causes a significant and concentration-dependent reduction of TNFalpha production. ERK1/2 may be a novel target to treat clinical patient of endotoxemia.

[Influence of chemotherapy on hematopoietic microenvironment and effect of autologous bone marrow stromal cell infusion on the recovery of hematopoiesis after chemotherapy]

OBJECTIVE

To observe the influence of chemotherapy on hematopoietic progenitor cells (HPC) and hematopoietic microenvironment (HME). To observe whether intravenous infusion of autologous bone marrow stromal cells (ABMSC) expanded in vitro can improve the hematopoietic function.

METHODS

Cultures of CFU-GM, BFU-E, CFU-E and stromal progenitor cells (CFU-F) from normal control and chemotherapeutic patients were performed. The stromal function was analyzed by the assessment of the area of flask surface covered by stromal cells (ASSC) and the time when stromal cells reach confluence (TC). The recovery of hematopoietic function in short term chemotherapy group and long term chemotherapy, with or without ABMSC infusion (1.1 - 8.7) x 10(8) post chemotherapy groups was observed.

RESULTS

The yields of CFU-GM, BFU-E, CFU-E and CFU-F in long term chemotherapy group were significantly lower than that in normal group or in short term chemotherapy group. There was no significant difference among three groups in the ASSC and TC. In long term chemotherapy group, the yields of CFU-GM, CFU-E, BFU-E and CFU-F after chemotherapy with BMSC infusion were significantly higher than that without BMSC infusion. In long term chemotherapy group, the lowest value of white blood cell (WBC) and platelet after chemotherapy with BMSC infusion was significantly higher than that without BMSC infusion. The times for WBC and platelets recovered to normal were significantly shorter in BMSC group than in without BMSC. No adverse reaction was observed with ABMSC infusion.

CONCLUSION

Long term chemotherapy results in severe impairment in HPC and mesenchymal progenitor cell (MPC), but has no obvious influence on the in vitro BMSC confluent layer formation. Intravenous infusion of expanded ABMSC can accelerate the recovery of hematopoiesis after chemotherapy.

Apoptosis of renal tubular cells in congenital hydronephrosis

OBJECTIVE

To assess apoptosis in congenital hydronephrosis and discuss its clinical significance.

METHODS

Apoptosis was detected in 15 kidneys from children with congenital hydronephrosis (5 mild hydronephrosis, 5 moderate hydronephrosis and 5 severe hydronephrosis) using the electronmicroscope, in situ gap labeling of fragmented nuclear DNA and DNA fragmentation analysis.

RESULTS

Apoptosis was seen in kidneys from children with congenital hydronephrosis. Margination of nuclear chromatin was identified and rounded apoptotic bodies were seen. The mean apoptotic index was 0.0941 +/- 0.017 in severe hydronephrosis, 0.0325 +/- 0.0169 in moderate hydronephrosis, and 0.0021 +/- 0.0031 in mild hydronephrosis. There was a significant difference between severe and moderate hydronephrosis (P = 0.0005), as well as between moderate and mild hydronephrosis (P = 0.0154). Moreover, with an increasing degree of hydronephrosis, the number of apoptotic cells also increased. Five kidneys with severe hydronephrosis and one kidney with moderate hydronephrosis showed typical apoptotic bands.

CONCLUSION

Apoptosis might participate in damaging kidneys in children with congenital hydronephrosis.

Australian Lasioglossum + Homalictus form a monophyletic group: resolving the "Australian enigma"

The bee genus Lasioglossum includes > 1,000 species of bees distributed on all continents except Antarctica. Lasioglossum is a major component of the bee fauna in the Holarctic, Ethiopian, and Asian regions and is an important group for investigating the evolution of social behavior in bees. Given its cosmopolitan distribution, the historical biogeography of the genus is of considerable interest. We reconstructed phylogenetic relationships among the subgenera and species within Lasioglossum s.s., using DNA sequence data from a slowly evolving nuclear gene, elongation factor-1 alpha. The entire data set includes > 1,604 aligned nucleotide sites (including three exons plus two introns) for 89 species (17 outgroups plus 72 ingroups). Parsimony and maximum likelihood analyses provide strong evidence that the primarily Indoaustralian subgenera (Homalictus, Chilalictus, Parasphecodes) form a monophyletic group. Bootstrap support for the Australian clade ranged from 73% to 77%, depending on the method of analysis. Monophyly of the Australian Lasioglossum suggests that a single colonization event (by way of Southeast Asia and New Guinea) gave rise to a lineage of > 350 native Indoaustralian bees. We discuss the implications of Australian monophyly for resolving the "Australian enigma"--the similarity in social behavior among the Australian halictine bees relative to that of Holarctic groups.

Phylogenetic utility of the major opsin in bees (Hymenoptera: Apoidea): a reassessment

Major opsin (LW Rh) DNA sequence has been reported to provide useful data for resolving phylogenetic relationships among tribes of corbiculate bees based on analyses of 502 bp of coding sequence. However, the corbiculate tribes are believed to be of Cretaceous age, and strong support for insect clades of this age from small data sets of nucleotide sequence data has rarely been demonstrated. To more critically assess opsin's phylogenetic utility we generated an expanded LW Rh data set by sequencing the same gene fragment from 52 additional bee species from 24 tribes and all six extant bee families. Analyses of this data set failed to provide substantial support for monophyly of corbiculate bees, for relationships among corbiculate tribes, or for most other well-established higher-level relationships among long-tongued bees. However, monophyly of nearly all genera and tribes is strongly supported, indicating that LW Rh provides useful phylogenetic signal at lower taxonomic levels. When our expanded LW Rh data set is combined with a morphological and behavioral data set for corbiculate bees, the results unambiguously support the traditional phylogeny of the corbiculate bee tribes: (Euglossini + (Bombini + (Meliponini + Apini))). This implies a single origin of advanced eusocial behavior among bees rather than dual origins, as proposed by several recent studies.

Low incidence of severe aGVHD and accelerating hemopoietic reconstitution in allo-BMT using lenograstim stimulated BM cells

OBJECTIVES

To investigate the efficacy of accelerating hemopoietic reconstraction and reducing a graft versus host disease (GVHD) in Allo-BMT receiving lenograstim stimulated donor marrow and to assess the preliminary biological mechanism.

METHODS

The donors for thirty patients (study group) with leukemia were given lenograstim 3-4 micrograms.kg-1.d-1 for seven days prior to marrow harvest. The results of subsequent engraftment in the recipients was compared with fifteen donors without G-CSF (control group). Five donors themselves were studied to assess the effects of lenograstion on hematopoietic progenitor cells and lymphocyte subsets in BM.

RESULTS

The stimulated bone marrow contained a higher number of nucleated cells, CFU-GM and CD34+ cells (P < 0.01). The hematopoetic reconstitution was accelerated. Until granulocyte counts exceeded 0.5 x 10(9)/L and plalete counts exceeded 20 x 10(9)/L, the days were 16.7 +/- 3.2 and 18.4 +/- 3.0 days as compared with those of the control group (22.5 +/- 5.1 and 26.3 +/- 5.9 days respectively, P < 0.01). The incidence of grade II-IV aGVHD was very low, only one case with grade II aGVHD on the skin in the study group. Four out of fifteen patients (26.7%) in the control group had grade II-IV aGVHD (P < 0.05). The number of T lymphocyte subsets in the harvested BM stimulated by G-CSF changed. In comparison with the control group, CD4+ decreased and CD8+ increased significantly (P < 0.01). The changes of progenitor cells and T lymphocyte subsets in BM from pre- to post-G-CSF stimulation indicated that the percentage of CD4+ cells reduced (P < 0.05), that of CD8+ cells, and that of CD34+ increased (P < 0.01). The incidence of chronic GVHD and relapse of leukemia were not different significantly between both groups.

CONCLUSIONS

Allogenic bone marrow transplant (Allo-BMT) donors given G-CSF can accelerate engraftment and minimize the incidence of severe aGVHD. There is a trend in favour of improved transplant-related complications.

Separation and determination of strychnine and brucine in Strychnos nux-vomica L. and its preparation by capillary zone electrophoresis

A capillary zone electrophoresis method was developed for the separation and determination of strychnine and brucine in Strychnos nux-vomica L. and its preparation. The factors that could affect the separation were studied, such as the types and concentrations of electrolytes, pH, ionic strength and organic modifier. The optimum running buffer was 20 mmol/L of ammonium acetate containing 0.2 mol/L of glacial acetic acid (pH 3.64). The applied voltage was 25 kV and the wavelength of the UV detector was set at 214 nm. The established method with dopamine hydrochloride as internal standard was linear in the range of 5-100 microg/mL for both strychnine and brucine. The recovery was 102.96% for strychnine and 98.56% for brucine. The extracts of Strychnos nux-vomica and its preparation could be directly injected for analysis.

[Graf's ultrasound examination method in assessment of dysplasia and congenital dislocation of infant hip]

OBJECTIVE

To discuss the application of Graf's sonographic method in assessment of developmental dysplasia and dislocation of infant hip.

METHODS

2258 infants (4516 hips) were examined and evaluated by Graf's method.

RESULTS

The analysis of data showed that type I hip accounted too 78.99%, type II 20.56%, and type III and type IV 0.45%.

CONCLUSION

Graf's method can provide qualitative and quantitative evaluation for hips of infants in 3 months after birth. It is an effective in developmental dysplasia of the hip (DDH) and is also useful for early treatment and follow-up of DDH.

Human glioma cell BT325 expresses a proteinase that converts human plasminogen to kringle 1-5-containing fragments

Angiostatin, a specific angiogenesis inhibitor, is an internal fragment of plasminogen, and can be generated in many systems mediated by different enzymes in vitro. The mechanism of angiostatin generation in vivo has not been well defined. Here we demonstrated that human glioma cell line BT325 can express an enzyme that can convert purified plasminogen to angiostatin-like fragments with molecular masses of 65, 60, and 58 kDa, respectively. These fragments have an identical N-terminal as KVYLS, which starts from Lys(98) of the plasminogen precusor. According to their molecular mass, the three fragments should comprise kringle domain 1 to kringle domain 5 (kringle 1-5). The proteolytic fragments obtained as above can inhibit the growth of bovine aortic endothelial (BAE) cells specifically. The proteolysis process can be completely inhibited by serine proteinase inhibitors, and partially inhibited by EDTA. The molecular weight of the peptide, which contains an enzymatic activity responsible for the proteolysis, was 13 kD determined by gel filtration and SDS-PAGE. The present data suggest that glioma cell BT325 can produce a novel proteinase to generate kringle 1-5 of plasminogen as an angiogenesis inhibitor.

Electronic and vibrational spectra of a series of substituted carbazole derivatives

The FTIR and FTR spectra of halogen (Cl, Br, I) substituted carbazole and their N-acetic and propionic acids have been recorded. A number of lines have been assigned on the basis of previous studies on the parent compound and by comparisons with the characteristic vibrations of their constituent structural units as well as comparing the spectra from FTIR and FTR. Some substituent-sensitive bands and characteristic bands were found. The electronic absorption spectra of these compounds in acetonitrile were also measured and are briefly discussed.

Neural electrophysiological studies on the external anal sphincter in children with anorectal malformation

BACKGROUND/PURPOSE

Abnormality of innervation of external anal sphincter is one of the most important factors affecting postoperative anorectal function. The abnormalities of lumbosacral nerves have been reported in many radiological and histopathologic studies. There are few reports on the neurophysiological changes in children with anoractal malformation. The aim of this study was to examine the functional changes of nerves to the external anal sphincter in anorectal malformation.

METHODS

Forty-five patients with anorectal malformation underwent studies of latencies of pudendo-anal reflex, spinoanal response, and evoked potential of cauda equine simultaneously. The conduction time of afferent nerve, efferent nerve, and sacral spinal center of pudendo-anal reflex arc were analyzed quantitatively.

RESULTS

The latencies of pudendo-anal reflex, spino-anal response, and conduction time of sacral spinal center significantly are prolonged in patients with anorectal malformation (P< .05). There was significant difference between rectourethral fistula group and vestibular fistula group as well as low-type deformity group. The patients with lumbosacral anomalies such as lumbosacral spinal bifida or absence of S4 or S5 had prolonged latencies, especially the pudendo-anal reflex latency. There was significant negative correlation between the latencies and clinical scores. Although pudendoanal reflex latency was longer in patients who had posterior sagittal anorectoplasty than those who had abdominoperineal pull-through procedure, the difference was not significant.

CONCLUSIONS

The abnormality of nerves to external anal sphincters is one of the important causes for clinical outcome. The neural lesions vary in each type of anal and lumbosacral deformity.

Free energy and information contents of conformons in proteins and DNA

Sequence-specific conformational strains (SSCS) of biopolymers that carry free energy and genetic information have been called conformons, a term coined independently by two groups over two and a half decades ago [Green, D.E., Ji, S., 1972. The electromechanochemical model of mitochondrial structure and function. In: Schultz, J., Cameron, B.F. (Eds.), Molecular Basis of Electron Transport. Academic Press, New York, pp. 1-44; Volkenstein, M.V., 1972. The Conformon. J. Theor. Biol. 34, 193-195]. Conformons provide the molecular mechanisms necessary and sufficient to account for all biological processes in the living cell on the molecular level in principle--including the origin of life, enzymic catalysis, control of gene expression, oxidative phosphorylation, active transport, and muscle contraction. A clear example of SSCS is provided by SIDD (strain-induced duplex destabilization) in DNA recently reported by Benham [Benham, C.J., 1996a. Duplex destabilization in superhelical DNA is predicted to occur at specific transcriptional regulatory regions. J. Mol. Biol. 255, 425-434; Benham, C.J., 1996b. Computation of DNA structural variability--a new predictor of DNA regulatory regions. CABIOS 12(5), 375-381]. Experimental as well as theoretical evidence indicates that conformons in proteins carry 8-16 kcal/mol of free energy and 40-200 bits of information, while those in DNA contain 500-2500 kcal/mol of free energy and 200-600 bits of information. The similarities and differences between conformons and solitons have been analyzed on the basis of the generalized Franck-Condon principle [Ji, S., 1974a. A general theory of ATP synthesis and utilization. Ann. N.Y. Acad. Sci. 227, 211-226; Ji, S., 1974b. Energy and negentropy in enzymic catalysis. Ann. N.Y. Acad. Sci. 227, 419-437]. To illustrate a practical application, the conformon theory was applied to the molecular-clamp model of DNA gyrase proposed by Berger and Wang [Berger, J.M., Wang, J.C., 1996. Recent developments in DNA topoisomerases II structure and mechanism. Curr. Opin. Struct. Biol. 6(1), 84-90], leading to the proposal of an eight-step molecular mechanism for the action of the enzyme. Finally, a set of experimentally testable predictions has been formulated on the basis of the conformon theory.

Growth hormone regulates leptin gene expression in bovine adipose tissue: correlation with adipose IGF-1 expression

Leptin, the product of the ob gene, is secreted from white adipocytes and regulates food intake and whole-body energy metabolism. In rodents and humans, leptin gene expression is under complex endocrine and metabolic control, and is strongly influenced by energy balance. Growth hormone (GH) has myriad effects on adipose tissue metabolism. The primary aim of this study was to determine the ability of GH to regulate leptin mRNA expression in bovine adipose tissue in vitro and in vivo. Incubation of subcutaneous adipose tissue explants for 24 h with GH alone had no effect on bovine leptin gene expression, whereas high concentrations of insulin or dexamethasone (DEX) potently stimulated bovine leptin mRNA abundance. GH, in combination with high concentrations of insulin, DEX, or both, attenuated the ability of insulin or DEX to stimulate leptin expression in vitro. These data indicate that GH can indirectly regulate leptin expression in vitro by altering the adipose tissue response to insulin or DEX. We extended these studies to examine the ability of GH to regulate leptin expression in vivo, using young castrate male cattle treated with no hormone (control) or GH (200 micrograms/kg body weight per day) for 3 days. GH increased plasma GH and insulin concentrations, but not those of cortisol or non-esterified fatty acid (NEFA) concentrations. GH treatment increased adipose tissue leptin and IGF-1 mRNA concentrations (n=9, P>0.001). In addition, leptin abundance was highly correlated with adipose tissue IGF-1 mRNA in GH-treated animals (P>0.001). The timing of GH-induced changes in leptin gene expression preceded measurable GH effects on adiposity.

[Neural electrophysiological observations on the external anal sphincter in patients with anorectal malformation]

OBJECTIVE

To explore the functional damage of the nerves controlling external anal sphincter in patients with congenital anorectal malformation and to design a new method for measuring the conductive time of sacral spinal center in the pudendo-anal reflex arc.

METHODS

45 patients with anorectal malformation and 20 normal subjects were subjected to detect the latency for pudendo-anal reflex, spinal-anal response and evoked potential of caude equine simultaneously. The conduction time of afferent motor nerve, efferent sense nerve and sacral spinal center in the pudendo-anal reflex arc were quantitatively analyzed.

RESULTS

The normal latency for pudendo-anal reflex was 23.3 +/- 6.9 ms, for spinal-anal response was 4.6 +/- 1.9 ms, and for evoked potential of caude equine was 3.8 +/- 0.9 ms. The conduction time of sacral spinal center was 14.8 +/- 6.6 ms. In patients with anorectal malformation, the latencies were prolonged obviously, especially the conduction time of sacral spinal center. There was a significant negative correlation between the latency and clinical scores. The correlation coefficient for pudendo-anal reflex was -0.68, for spinal-anal response was -0.64, and for conduction time of sacral spinal center was -0.60.

CONCLUSIONS

The abnormality of nerves serving anal sphincters was one of the important causes for postoperative fecal incontinence. The neural lesions are specially serious in the sacral spinal center.