Is there a reduced risk of breast cancer among women with hip fractures?

To test the hypothesis that osteoporosis, which results partly from long-term estrogen deficiency, is associated with a lowered risk of breast cancer, a population-based cohort study was performed in Amiens. To ascertain the incidence of breast cancer, 1300 women were followed through after a first hip fracture. Overall, 18 cases of cancer were observed cf. 21.8 expected (standardized incidence ratio (SIR): 0.82; 95% confidence interval (CI): 0.5-1.3). The results are consistent with previous studies which concluded that long-term estrogen deficiency is associated with a reduced risk of developing breast cancer.

Extragenic suppressors of the Arabidopsis gai mutation alter the dose-response relationship of diverse gibberellin responses

Active gibberellins (GAs) are endogenous factors that regulate plant growth and development in a dose-dependent fashion. Mutant plants that are GA deficient, or exhibit reduced GA responses, display a characteristic dwarf phenotype. Extragenic suppressor analysis has resulted in the isolation of Arabidopsis mutations, which partially suppress the dwarf phenotype conferred by GA deficiency and reduced GA-response mutations. Here we describe detailed studies of the effects of two of these suppressors, spy-7 and gar2-1, on several different GA-responsive growth processes (seed germination, vegetative growth, stem elongation, chlorophyll accumulation, and flowering) and on the in planta amounts of active and inactive GA species. The results of these experiments show that spy-7 and gar2-1 affect the GA dose-response relationship for a wide range of GA responses and suggest that all GA-regulated processes are controlled through a negatively acting GA-signaling pathway.

[GC-MS analysis and inhibitory activity of the essential oil extracted from the leaves of Lindera communis]

The essential oil isolated from the dried leaves of Lindera communis was analyzed by means of gas chromatography-mass(GC-MS) technique, the structures of 23 chemical components were identified from it in total, among these, (-)-spathulenol(relative content 22.50%), endo-1,3,3-trimethyl-2-norbornanol, acetate (10.06%), caryophyllene oxide (6.74%) and germacrene B(6.71%) were the main constituents. And also the oil in vitro exhibited manifest antifungal and antibacterial activities against 4 fungi pathogen species and 4 bacterial species with MIC between 0.08-0.8 ml/l.

Interactions between Tat and TAR and human immunodeficiency virus replication are facilitated by human cyclin T1 but not cyclins T2a or T2b

The transcriptional transactivator (Tat) from the human immunodeficiency virus (HIV) does not function efficiently in Chinese hamster ovary (CHO) cells. Only somatic cell hybrids between CHO and human cells and CHO cells containing human chromosome 12 (CHO12) support high levels of Tat transactivation. This restriction was mapped to interactions between Tat and TAR. Recently, human cyclin T1 was found to increase the binding of Tat to TAR and levels of Tat transactivation in rodent cells. By combining individually with CDK9, cyclin T1 or related cyclins T2a and T2b form distinct positive transcription elongation factor b (P-TEFb) complexes. In this report, we found that of these three cyclins, only cyclin T1 is encoded on human chromosome 12 and is responsible for its effects in CHO cells. Moreover, only human cyclin T1, not mouse cyclin T1 or human cyclins T2a or T2b, supported interactions between Tat and TAR in vitro. Finally, after introducing appropriate receptors and human cyclin T1 into CHO cells, they became permissive for infection by and replication of HIV.

[Use of diagnostic ultrasound of sinus in the paranasal sinus disease]

OBJECTIVE

To utilize the diagnostic A ultrasound of sinuses in the diagnosis of paranasal sinus disease.

METHOD

Through history enquirement, careful clinical otorhinolaryngological examination, X-ray examination of paranasal sinus, CT, maxillary sinus puncture and examination of the diagnostic ultrasound of sinus, we observed 115 patients with paranasal sinus disease and compared them with 22 normal people who were in control group.

RESULTS

In normal people, the according rate between ultrasound examination and clinicaly diagnostic methods, include history enquirement, otorhinolaryngological examination, X-ray examination, CT and maxillary puncture, is 100%. And in the group of patients with paranasal disease, the according rate is 62.5%-92%.

CONCLUSION

The diagnostic A ultrasound of sinus has high accuracy, the control is easy, the cost is relatively lower, it can be used repeatedly and do no harm to the patient's health. It is a good method and assistant technigue in the diagnosis of frontal and maxillary sinus disease.

A baculovirus enhancin alters the permeability of a mucosal midgut peritrophic matrix from lepidopteran larvae

The peritrophic matrix (PM) in lepidopterous larvae may function as a defensive barrier against ingested viral pathogens. PMs isolated from Trichoplusia ni and Pseudaletia unipuncta larvae, were treated with a baculovirus-encoded metalloprotease (enhancin) from Trichoplusia ni granulosis virus (TnGV) and their in vitro permeability to blue dextran and fluorescent-labelled Autographa californica nuclear polyhedrosis virus (AcMNPV) was determined using a dual chamber permeability apparatus. Incubation of T. ni PMs with 0.0, 0.5, 1.0, and 2.0mg/ml enhancin resulted in a blue dextran 2000 flux of 4.4, 6.3, 9.9, and 15.6&mgr;g/mm(2)/h, respectively. In addition, T. ni PMs treated with enhancin were found to be significantly more permeable to fluorescent-labelled AcMNPV than non-treated control PMs. The permeability of T. ni PMs treated with 3.0mg/ml enhancin was 0.017 cumulative percent crossing/mm(2)/h, whereas the permeability of the control PM was below the detectable limit. Similarly, enhancin treatment greatly increased the permeability of P. unipuncta PMs to AcMNPV. These results provide evidence that the PM from two lepidopteran species can block the passage of baculovirions across this matrix thus reducing the probability of larval infection. Furthermore, these results support the hypothesis that enhancin facilitates NPV infection of larvae by altering the permeability of the PM.

Varicella-zoster virus Fc receptor component gI is phosphorylated on its endodomain by a cyclin-dependent kinase

Varicella-zoster virus (VZV) glycoprotein gI is a type 1 transmembrane glycoprotein which is one component of the heterodimeric gE:gI Fc receptor complex. Like VZV gE, VZV gI was phosphorylated in both VZV-infected cells and gI-transfected cells. Preliminary studies demonstrated that a serine 343-proline 344 sequence located within the gI cytoplasmic tail was the most likely phosphorylation site. To determine which protein kinase catalyzed the gI phosphorylation event, we constructed a fusion protein, consisting of glutathione-S-transferase (GST) and the gI cytoplasmic tail, called GST-gI-wt. When this fusion protein was used as a substrate for gI phosphorylation in vitro, the results demonstrated that GST-gI-wt fusion protein was phosphorylated by a representative cyclin-dependent kinase (CDK) called P-TEFb, a homologue of CDK1 (cdc2). When serine 343 within the serine-proline phosphorylation site was replaced with an alanine residue, the level of phosphorylation of the gI fusion protein was greatly reduced. Subsequent experiments with individually immunoprecipitated mammalian CDKs revealed that the VZV gI fusion protein was phosphorylated best by CDK1, to a lesser degree by CDK2, and not at all by CDK6. Transient-transfection assays carried out in the presence of the specific CDK inhibitor roscovitine strongly supported the prior results by demonstrating a marked decrease in gI phosphorylation while gI protein expression was unaffected. Finally, the possibility that VZV gI contained a CDK phosphorylation site in its endodomain was of further interest because its partner, gE, contains a casein kinase II phosphorylation site in its endodomain; prior studies have established that CDK1 can phosphorylate casein kinase II.

[Determination of glycyrrhizic acid in glycyrrhiza preparations with capillary electrophoresis and high performance liquid chromatography]

High performance liquid chromatography (HPLC), capillary zone electrophoresis (CZE) and micellar electrokinetic capillary chromatography(MECC) have been used to determine glycyrrhizic acid in glycyrrhiza preparations. By HPLC, mobile phase was V(methanol):V(water):V(acetic acid) = 75:23.5:1.5. By CZE, experiment was performed with 15 kV power, 0.075 mm i.d. x 800 mm fused-silica capillary column and UV detector. Samples were injected into the capillary by electromigration injection for 20 s. Absorbance detection was at 254 nm. The running buffer was made up of 0.02 mol/L dipotassium hydrogenphosphate and borax (pH 9.0). By MECC, the running buffer was made up of 0.025 mol/L sodium dodecyl sulfate (SDS), 0.02 mol/L dipotassium hydrogenphosphate and borax (pH 9.0). Each new capillary was washed with 0.1 mol/L NaOH, deionized water and buffer, each for 3 min, before use. Comparison of the results of analysis with HPLC, CZE and MECC has been made. It was found that result of MECC was very close to that of HPLC. MECC has been satisfactorily applied to plant drug analysis.

Synergistic effects of mycophenolate mofetil and sirolimus in prevention of acute heart, pancreas, and kidney allograft rejection and in reversal of ongoing heart allograft rejection in the rat

BACKGROUND

The effect of mycophenolate mofetil (MMF) and sirolimus (rapamycin, RAPA) mono- and combination-therapy was examined in prevention of acute heart, pancreas, and kidney allograft rejection and in reversal of ongoing heart allograft rejection in the rat.

METHODS

Both drugs were administered orally for up to 30 days. Eleven groups (n=6) were involved in the first part of the heart allografting model. Brown Norway (RT1n) to Lewis (RT1(1)) combination was used in the heart and pancreas transplantation models, whereas Buffalo (RT1b) to Wistar Furth (RT1u) was used in the kidney transplantation model.

RESULTS

The naive control group showed a mean survival time of 6.5+/-0.6 days. There were graded dose-responses to monotherapy of MMF 10 and 20 mg(kg/ day (12.5+/-2.6 days; 19.3+/-9.0 days) and RAPA 0.2, 0.4, 0.8, and 1.8 mg/kg/day (19.2+/-2.0 days; 30.0+/-7.3 days; 50.8+/-12.5 days; 51.2+/-2.6 days), respectively (P=0.001). Results with the combined use of drugs indicate that a synergistic or very strong synergistic interaction was produced when compared with monotherapy of MMF or RAPA: MMF 10 mg(kg/day+RAPA 0.2 mg/kg(day (52.7+/-5.7 days, combination index [CI] =0.189), MMF 20 mg(kg/day+RAPA 0.2 mg/kg/day (57.7+/-5.7 days, CI=0.084), MMF 10 mg/kg/day+RAPA 0.4 mg(kg/day (50.2+/-13.5 days, CI=0.453), and MMF 20 mg/kg(day+ RAPA 0.4 mg/kg(day (51.5+/-6.8 days, CI=0.439), respectively. These results were repeatable in the prevention of acute pancreas and kidney allograft rejection in the rat. In the second part of the study of reversal of ongoing acute heart allograft rejection model, the combined treatment of MMF 10 mg/kg(day+RAPA 0.2 mg/ kg(day (35.5+/-16.0 days, CI=0.794) and MMF 20 mg/kg day+RAPA 0.2 mg(kg/day (57.2+/-4.7 days, CI=0.310) represented synergistic interaction compared with monotherapy of MMF or RAPA.

CONCLUSIONS

Concomitant therapy of MMF and RAPA produces a synergistic effect in prevention of heart, pancreas, and kidney allograft rejection and in reversal of ongoing heart allograft rejection in the rat.

Upregulation of cyclin T1/CDK9 complexes during T cell activation

Cyclin T1 has been identified recently as a regulatory subunit of CDK9 and as a component of the transcription elongation factor P-TEFb. Cyclin T1/CDK9 complexes phosphorylate the carboxy terminal domain (CTD) of RNA polymerase II (RNAP II) in vitro. Here we report that the levels of cyclin T1 are dramatically upregulated by two independent signaling pathways triggered respectively by PMA and PHA in primary human peripheral blood lymphocytes (PBLs). Activation of these two pathways in tandem is sufficient for PBLs to enter and progress through the cell cycle. However, the expression of cyclin T1 is not growth and/or cell cycle regulated in other cell types, indicating that regulation of cyclin T1 expression is dependent on tissue-specific signaling pathways. Upregulation of cyclin T1 in stimulated PBLs results in induction of the CTD kinase activity of the cyclin T1/CDK9 complex, which in turn correlates directly with phosphorylation of RNAP II in vivo, linking for the first time activation of the cyclin T1/ CDK9 pair with phosphorylation of RNAP II in vivo. In addition, we report here that endogenous CDK9 and cyclin T1 complexes associate with HIV-1 generated Tat in relevant cells and under physiological conditions (HIV-1 infected T cells). This, together with our results showing that HIV-1 replication in stimulated PBLs correlates with the levels of cyclin T1 protein and associated CTD kinase activity, suggests that the cyclin T1/CDK9 pair is one of the HIV-1 required host cellular cofactors generated during T cell activation.

A clinical investigation on massage for prevention and treatment of recurrent respiratory tract infection in children

The TCM therapeutic principle of "eliminating the pathogenic factors by supporting the healthy energy" was adopted in massage to treat and prevent recurrent respiratory tract infection of children. Susceptible and healthy children of the same age were used as controls. As a result, the therapeutic effect of the treatment group is significantly better than that of the controls, with all of the immunologic indexes being approximately normal when the patients were reexamined 3 and 6 months after the massage. Statistically, the difference was significant (P < 0.01). Massage has been proved very helpful in improving the general constitution, enhancing the immune functions, preventing and treating the condition, and in health care as well.

Gibberellin: inhibitor of an inhibitor of...?

Gibberellin is an endogenous plant growth regulator. Here, we describe our present understanding of how gibberellin regulates plant growth, using recent results gained from studies of gibberellin-signalling mutants of Arabidopsis. These results show that a signalling pathway represses plant growth and that gibberellin releases this repression. In consequence, the well-known growth-promoting properties of gibberellin are due to its activity as an "inhibitor of an inhibitor" [Brian Pw. Sym Soc. Exp Bio 1957; 11:166-182 (Ref. 1)] of plant growth.

Gibberellin: inhibitor of an inhibitor of...?

Gibberellin is an endogenous plant growth regulator. Here, we describe our present understanding of how gibberellin regulates plant growth, using recent results gained from studies of gibberellin-signalling mutants of Arabidopsis. These results show that a signalling pathway represses plant growth and that gibberellin releases this repression. In consequence, the well-known growth-promoting properties of gibberellin are due to its activity as an "inhibitor of an inhibitor" [Brian Pw. Sym Soc. Exp Bio 1957; 11:166-182 (Ref. 1)] of plant growth.

Molecular cloning and characterization of a cDNA encoding canine type VII collagen non-collagenous (NC1) domain, the target antigen of autoimmune disease epidermolysis bullosa acquisita (EBA)

Type VII collagen, the major component of anchoring fibrils, serves as tight adhesion of skin basement membrane zone (BMZ) through its amino-terminal non-collagenous (NC1) domain. The NC1 domain is targeted by autoantibodies of an acquired blistering skin disease termed epidermolysis bullosa acquisita (EBA) naturally occurring in humans and dogs. We cloned the full-length canine type VII collagen NC1 domain cDNA and delineated its molecular and immunological characteristics. The canine NC1 domain cDNA consists of 3759 nucleotides encoding for 1253 amino acids, with a molecular mass of approx. 134 kDa and a 17 amino acid signal peptide. The expression of canine type VII collagen was confirmed by Northern blot analysis and by a rabbit antibody raised against a 17 amino acid peptide deduced from canine NC1 sequence. Comparison of canine NC1 with the corresponding human sequence indicated 86.7% and 87.6% identity at the nucleotide and deduced amino acid levels respectively. The protein homology reached greater than 95% within two immunodominant epitope areas. Furthermore, human EBA autoantibodies and a rabbit anti-human NC1 cross-reacted with canine skin BMZ and the newly synthesized canine type VII collagen. The molecular and immunological identities between human and canine NC1 domains suggest that NC1 may be critical for the EBA development.

Quantitative characterization of the binding of histamine by heparin

Tissue histamine is stored in mast cell granules, presumably as a histamine-heparin complex. Heparin is a polyelectrolyte, with a fraction of its anionic charge neutralized by condensed counterions. The interaction of heparin with histamine in aqueous solution was quantitatively characterized by 1H nuclear magnetic resonance (NMR) spectroscopy. Binding constants were determined from chemical shift-pH titration data for the C2H proton of the imidazolium ring for a wide range of histamine, heparin, and Na+ concentrations. The results indicate a binding stoichiometry of 1 histamine per heparin disaccharide repeat unit. The binding is electrostatic, as indicated by the strong dependence of the binding constant on Na+ concentration. From an analysis of the binding constants using the counterion condensation theory of polyelectrolytes, it was determined that the binding of H2A2+ results in displacement of 1.72 Na+ ions from the counterion condensation volume of heparin and that H2A2+ makes 2 ionic interactions with heparin. The displacement of Na+ from the counterion condensation volume of heparin by H2A2+ was also studied by 23Na NMR. From 23Na spin-lattice relaxation time data, it was determined directly that 1.78 Na+ ions are displaced per H2A2+ bound by heparin. The results are discussed in terms of the ion exchange process which takes place when histamine is released by mast cells.

The ability of positive transcription elongation factor B to transactivate human immunodeficiency virus transcription depends on a functional kinase domain, cyclin T1, and Tat

By binding to the transactivation response element (TAR) RNA, the transcriptional transactivator (Tat) from the human immunodeficiency virus increases rates of elongation rather than initiation of viral transcription. Two cyclin-dependent serine/threonine kinases, CDK7 and CDK9, which phosphorylate the C-terminal domain of RNA polymerase II, have been implicated in Tat transactivation in vivo and in vitro. In this report, we demonstrate that CDK9, which is the kinase component of the positive transcription elongation factor b (P-TEFb) complex, can activate viral transcription when tethered to the heterologous Rev response element RNA via the regulator of expression of virion proteins (Rev). The kinase activity of CDK9 and cyclin T1 is essential for these effects. Moreover, P-TEFb binds to TAR only in the presence of Tat. We conclude that Tat-P-TEFb complexes bind to TAR, where CDK9 modifies RNA polymerase II for the efficient copying of the viral genome.

[Nasopharyngeal carcinoma and dermatomyositis (analysis of 12 cases)]

The onset relationship between dermatomyositis (DM) and malignant tumor, especially nasopharyngeal carcinoma (NPC), was approached. Approximately 90 cases of DM were admitted in the hospital. Among them 15 cases were complicated with malignant tumor of which 12 cases were complicated with NPC (account for 80% of DM with complicated carcinoma). In addition to treat these patients with prednisone and antibiotics, radiation therapy has been applied for NPC and metastasis in the neck. During the hospitalizations, one patient died, eleven patients' NPC was controlled, and the DM was completely resolved or improved. There is an obvious relationship between DM and carcinoma. DM may improve or even subside with good short term prognosis, as long as the carcinoma is controlled successfully.

Newly developed initial-flow cell filtrometer and the comparison with viscometry and ektacytometry on erythrocyte deformability

According to Hanss's initial-flow rate method, F. Liao designed a new cell filtrometer in the early 1990s. The parameters, cell initial transit time (Tc) and membrane clogging rate (CR), can be determined by a single measurement with timing accuracy of 1 ms. The new cell filtrometer has two valuable features: a button-pushing operation to control electromagnetic valves; and an autocirculation of fluid in the cell filtrometer resulting in the same volume of leading fluid. A series of comparisons of the new filtrometry with viscometry or ektacytometry shows that the instrument seems to be more sensitive in detecting subpopulations of glutaraldehyde-hardened cells and the shift of deformability for all the cells. The reproducibility of the filtrometer for different membranes made in China and the USA is reasonable (CV < 5% for Tc). Preliminary application of the filtrometer indicates that it might be useful for trial study and routine clinical application.

[Intrahepatic portal vein compliance in cirrhosis]

OBJECTIVE

To elaborate the effects of increase in portal flow on intrahepatic vein compliance with isolated perfused cirrhotic model (IPCM).

METHOD

Cirrhosis was induced by CCl(4) in 80 Wistar rats, which were divided into two groups A and B, by portal with/without hepato-artery. Portal flow was increased and hemodynamic parameters were recorded and analysed.

RESULT

In group A, compared with 1.65 +/- 0.28 kPa at basal control, portal pressure was elevated from 2.55 +/- 0.40 kPa to 3.96 +/- 0.67 kPa. Q(35)-Q(55) flow rates were raised from 35 to 55 ml/min, respectively. A correlation existed between portal flows and pressures (r = 0.985, P < 0.01). The low flow rate of 15 ml/min at Q(15) caused a irreversible model injury. A largest flow rate in IPCM was, less than in IPRL. In group B, no low flow-injury was found.

CONCLUSION

Portal vein compliance of liver is decreased markedly in cirrhotic portal hypertension, but hepatic flow is increased. There are likely some compensative relations between portal and hepato-arterial system.

Alpha-1 adrenergic receptors in liver plasma membranes of cirrhotic patients with portal hypertension: a quantitative study

OBJECTIVE

To investigate the changes of alpha-1 adrenergic receptors in cirrhotic liver and the relationship between the changes and the pathogenesis of portal hypertension.

METHODS

The concentration and affinity of alpha-1 adrenergic receptors in the liver plasma membranes of posthepatitic cirrhotic patients with portal hypertension were quantitatively measured using radioligand binding analysis.

RESULTS

Compared with 8 controls without hepatic pathological changes, the maximal binding capacity (Bmax) of 9 posthepatitic cirrhotic patients decreased (129.1 +/- 12.0 vs 142.1 +/- 14.1 fmol/mg protein, P > 0.05), dissociation constant (Kd) values increased (0.3945 +/- 0.0974 vs 0.2382 +/- 0.0548 nmol/L, P < 0.01), and the receptor maximal content (RMC) decreased (417.4 +/- 76.8 vs 739.9 +/- 167.6 fmol/g liver, P < 0.01).

CONCLUSIONS

The decreased concentration and affinity of alpha-1 adrenergic receptors may play an important role in the metabolic disturbances of catecholamines often seen in some cirrhotic patients, and have implications in the pathogenesis of portal hypertension.

Identification of a cyclin subunit required for the function of Drosophila P-TEFb

P-TEFb is required for the transition from abortive elongation into productive elongation and is capable of phosphorylating the carboxyl-terminal domain (CTD) of the largest subunit of RNA polymerase II. We cloned a cDNA encoding the large subunit of Drosophila P-TEFb and found the predicted protein contained a cyclin motif. We now name the large subunit cyclin T and the previously cloned small subunit (Zhu, Y. R., Peery, T., Peng, J. M., Ramanathan, Y., Marshall, N., Marshall, T., Amendt, B., Mathews, M. B., and Price, D. H. (1997) Genes Dev. 11, 2622-2632) cyclin-dependent kinase 9 (CDK9). Recombinant P-TEFb produced in baculovirus-transfected Sf9 cells exhibited 5, 6-dichloro-1-beta-D-ribofuranosylbenzimidazole-sensitive kinase activity similar to native P-TEFb. Kc cell nuclear extract depleted of P-TEFb failed to generate long DRB-sensitive transcripts, but this activity was restored upon addition of either native or recombinant P-TEFb. Like other CDKs, CDK9 is essentially inactive in the absence of its cyclin partner. P-TEFb containing a CDK9 mutation that knocked out the kinase activity did not function in transcription. Deletion of the carboxyl-terminal domain of cyclin T in P-TEFb reduced both the kinase and transcription activity to about 10%. The CDK-activating kinase in TFIIH was unable to activate the CTD kinase activity of P-TEFb.

[Magnetic resonance imaging of hypopharyngeal and cervical esophageal cancer]

Imaging by MR (MRI) and esophageal barium meal of 17 cases of hypopharyngeal and cervical esophageal cancer were analyzed. The results indicate that esophageal barium meal can not demonstrate the invading of neoplasms to the adjacent structure. Therefore, it is difficult to use the only data of esophageal barium meal for TNM staging. The results also indicate that MRI is more useful and reliable in assessing the three dimensional structure and the neoplasms invading to the adjacent structure. This results suggest that MRI is that useful in determining the diagnosis, TNM staging and the determining the appropriate operative therapy for hypopharyngeal and cervical esophageal cancer.

[Simultaneous determination of creatinine, pseudouridine and uric acid in serum and urine by high performance liquid chromatography]

In this paper a sensitive, rapid and simple HPLC method for the simultaneous determination of creatinine (Cr), pseudouridine (Pu) and uric acid(UA) has been established. We have evaluated clinical value of the method in the early diagnosis of diabetic nephropathy (DN). Separation was obtained using Shim-pack CLC-ODS 15 x 0.6 cm column and mobile phase of buffer solution of phosphate (pH 3.0, 0.02 mol/L) with flow rate of 1 mL/min. Detection was performed with UV detector at an automatic adjustment of wavelength. The recoveries of Cr, Pu and UA were 101.4%, 104.9% and 105.0% respectively. The calibration curves were linear within the concentration range of 8.6-274.6 mumol/L for Cr, 0.72-22.93 mumol/L for Pu and 19.1-612.7 mumol/L for UA (n = 6, r > 0.999, p < 0.01). The CV for within day and between day measurements were < 2.5% and < 5.0% respectively. In addition, Pu, Cr and UA were simultaneously determined in serum and urine of 39 patients with diabetic mellitus (DM). 15 patients with nephrotic syndrome (NS) and 53 normal subjects by the method. Results include: 1. the levels of serum Pu in all DM patients (100%) with microalbuminuria (MiAU) and macroalbuminuria (MaAU) were greater than maximum of normal subjects (X + 2S). In addition, in 9 DM patients (41%) with normal albuminuria (NAU) the levels were also greater than the maximum. 2. In patients with DM, there was no correlation between the serum Pu and the urinary albumin excretion (UAE), whereas the serum Pu correlated closely with the serum Cr. However, the incidence for serum Pu increase was significantly greater in patients. 3. The levels of serum Pu in patients with NS were greater than those in control subjects and patients with DM. Conclusion is that the determination of serum Pu could be used as sensitivity index for the early diagnosis of DN.

Identification of multiple cyclin subunits of human P-TEFb

The transition from abortive into productive elongation is proposed to be controlled by a positive transcription elongation factor b (P-TEFb) through phosphorylation of the carboxy-terminal domain (CTD) of the largest subunit of RNA polymerase II. Drosophila P-TEFb was identified recently as a cyclin-dependent kinase (CDK9) paired with a cyclin subunit (cyclin T). We demonstrate here the cloning of multiple cyclin subunits of human P-TEFb (T1 and T2). Cyclin T2 has two forms (T2a and T2b) because of alternative splicing. Both cyclin T1 and T2 are ubiquitously expressed. Immunoprecipitation and immunodepletion experiments carried out on HeLa nuclear extract (HNE) indicated that cyclin T1 and T2 were associated with CDK9 in a mutually exclusive manner and that almost all CDK9 was associated with either cyclin T1 or T2. Recombinant CDK9/cyclin T1, CDK9/cyclin T2a, and CDK9/cyclin T2b produced in Sf9 cells possessed DRB-sensitive kinase activity and functioned in transcription elongation in vitro. Either cyclin T1 or T2 was required to activate CDK9, and the truncation of the carboxyl terminus of the cyclin reduced, but did not eliminate, P-TEFb activity. Cotransfection experiments indicated that all three CDK9/cyclin combinations dramatically activated the CMV promoter.