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C Liu

Publications and source records attributed to C Liu.

At least 19 recordsLinked to original sources
PubMed2026

[Tafluprost/timolol fixed-dose combination versus tafluprost monotherapy for open-angle glaucoma and ocular hypertension: a multicenter, randomized, double-blind, parallel-group trial].

Objective: To evaluate the efficacy and safety of a preservative-free tafluprost/timolol maleate fixed-dose combination compared with preservative-free tafluprost monotherapy in Chinese patients with open-angle glaucoma (OAG) or ocular hypertension (OHT). Methods: This was a multicenter, randomized, double-blind, parallel-controlled clinical trial conducted across 25 centers, including the Eye & ENT Hospital of Fudan University, from January 2019 to November 2022. Patients diagnosed with OAG or OHT who required enhanced intraocular pressure (IOP) reduction after a 4-week washout period were enrolled. Participants were randomized 1&#x2236;1 to receive either tafluprost/timolol or tafluprost once daily for 3 months. The primary endpoint was the change from baseline in mean diurnal IOP (the average of measurements at 8:00, 10:00, and 16:00) at Month 3. Secondary endpoints included IOP changes at individual time points and the proportion of responders achieving predefined IOP reduction thresholds. Safety was assessed via the incidence of adverse events (AEs). Analysis of covariance (ANCOVA) using the Markov Chain Monte Carlo (MCMC) method was employed for the primary endpoint; superiority was established if the upper limit of the 95% confidence interval (CI) was<0 mmHg (1 mmHg=0.133 kPa). Continuous variables in secondary endpoints were compared using ANCOVA, and responder rates were analyzed using Fisher's exact test. Results: A total of 219 patients were enrolled (tafluprost/timolol group: n=110; tafluprost group: n=109). The primary efficacy analysis set included 215 patients (tafluprost/timolol: n=107; tafluprost: n=108). Baseline characteristics were well-balanced between the two groups. The majority of patients were male [127 (59.1%)] with a mean age of (44.80&#xb1;15.71) years at screening. At Month 3, the mean diurnal IOP reduction from baseline was (6.56&#xb1;3.44) mmHg in the tafluprost/timolol group and (5.36&#xb1;2.94) mmHg in the tafluprost group. After adjusting for baseline IOP, the between-group difference was -1.312 mmHg (95%CI: -2.010 to -0.696); as the upper limit was<0 mmHg, tafluprost/timolol demonstrated superior IOP-lowering efficacy to tafluprost. Responder rates for IOP reductions of&#x2265;15%,&#x2265;25%, and&#x2265;30% were significantly higher in the tafluprost/timolol group (P=0.016, 0.028, and 0.032, respectively). The incidence of ocular AEs was 20.0% (22/110) in the tafluprost/timolol group and 26.6% (29/109) in the tafluprost group. The most common AE was conjunctival hyperemia, occurring in 2.7% (3/110) and 8.3% (9/109) of the groups, respectively. Conclusion: Compared with preservative-free tafluprost monotherapy, the tafluprost/timolol combination provides significantly greater IOP reduction in patients with OAG and OHT, while maintaining a favorable safety profile.

Humans↗
PubMed1992

The role of the 2- and 3-hydroxyl groups of 1D-myo-inositol 1,4,5-trisphosphate in the mobilisation of calcium from permeabilised human 1321N1 astrocytoma cells.

The functional significance of the 2- and 3-hydroxyl groups of 1 D-myo-inositol 1,4,5-trisphosphate [Ins(1,4,5)P3] was probed by using Ins(1,4,5)P3 analogues variously modified at positions 2 and 3 or elsewhere. The intrinsic activities of these compounds were compared to that of Ins(1,4,5)P3, using the calcium-mobilising receptor of the 1321N1 human astrocytoma cell line. The ligand-binding affinities were also determined using membrane preparations from rat cerebellum and bovine adrenal cortex. The results show that HO-2 and HO-3 of Ins(1,4,5)P3 have a relatively insignificant role in receptor binding and calcium release. However, the possibility of a regulatory role for the 3-position of Ins(1,4,5)P3 in these processes is proposed.

Adrenal Cortex↗
PubMed1992

Sequence and variability of the 5.8S and 26S rRNA genes of Pneumocystis carinii.

The sequence of the coding region of the rRNA operon of rat-derived Pneumocystis carinii has been completed, including the genes for 5.8S and 26S rRNA. These genes show homology to the rRNA genes of yeast, and an apparent group I self-splicing intron is present in the 26S rRNA gene. Like a similar intron in the 16S rRNA gene, this intron is in a phylogenetically conserved region. Variation in the 26S rRNA sequence was noted between P. carinii organisms isolated from two different sources.

Base Sequence↗
PubMed1992

3-position modification of myo-inositol 1,4,5-trisphosphate: consequences for intracellular Ca2+ mobilisation and enzyme recognition.

The ability of the novel D-myo-inositol 1,4,5-trisphosphate (Ins(1,4,5)P3) analogues, L-chiro-inositol 2,3,5-trisphosphate (L-ch-Ins(2,3,5)P3) and D-3-deoxy-3-fluoro-myo-inositol 1,4,5-trisphosphate (3F-Ins(1,4,5)P3), to bind to the Ins(1,4,5)P3 receptor, mobilise intracellular Ca2+ stores and interact with metabolic enzymes has been investigated. L-ch-Ins(2,3,5)P3 and 3F-Ins(1,4,5)P3 were bound by the Ins(1,4,5)P3 receptor from bovine adrenal cortex with relatively high affinity (Ki values 60.4 and 8.0 nM respectively) but with lower affinity than Ins(1,4,5)P3 (KD = 5.9 nM). Both analogues were apparent full agonists at the Ca2+ mobilising receptor in SH-SY5Y cells, but were less potent than Ins(1,4,5)P3 (EC50 L-ch-Ins(2,3,5)P3 = 1.4 microM, 3F-Ins(1,4,5)P3 = 0.37 microM and Ins(1,4,5)P3 = 0.12 microM). L-ch-Ins(2,3,5)P3 and 3F-Ins(1,4,5)P3 were resistant to Ins(1,4,5)P3 3-kinase, and were potent inhibitors of the enzyme (Ki values 7.1 and 8.6 microM respectively). 3F-Ins(1,4,5)P3 was hydrolysed by Ins(1,4,5)P3 5-phosphatase at a similar rate to Ins(1,4,5)P3, but inhibited dephosphorylation of [3H]Ins(1,4,5)P3 with high potency (apparent Ki = 3.9 microM) L-ch-Ins(2,3,5)P3 was also recognised by the enzyme with high affinity (Ki = 7.7 microM) but was resistant to hydrolysis. These results suggest that the environment around C-3 is of major importance for recognition not only by Ins(1,4,5)P3 3-kinase but also by Ins(1,4,5)P3 5-phosphatase.

Adrenal Glands↗
PubMed1992

Kinetic differentiation between enzyme inactivation involving complex-formation with the inactivator and that involving a conformation-change step.

It has been suggested that the complexing type of inactivation in which the inactivator binds reversibly with the enzyme before inactivation cannot be differentiated kinetically from that a slow enzyme conformation change is involved as a first step [Rakitzis (1986) J. Theor. Biol. 122, 247-249]. The kinetics of the substrate reaction during modification of enzyme activity previously described [Tsou (1988) Adv. Enzymol. Relat. Areas Mol. Biol. 61, 381-436] have now been applied to this problem and equations derived to show that the slow-conformational-change type can be differentiated from the complexing type by plotting the final concentration of product formed, [P]infinity, against the reciprocal of inactivator concentration. The reaction of hexokinase with 2-chloromercuri-4-nitrophenol has been shown to involve a conformational change of the enzyme before inactivation.

Chloromercurinitrophenols↗
PubMed1992

Intracerebral chemotherapy in the 9L rat brain tumor model.

We have used the 9L rat brain tumor model to search for effective chemotherapeutic approaches to the management of brain tumors. Several antineoplastic agents which have been proposed or are currently being used for human brain tumors, including 1,3-bis (2-chloroethyl)-1-nitrosourea (BCNU), bleomycin, aziridinylbenzoquinone (AZQ), cis-Platinum, and acivicin, were administered intravenously (iv), intraperitoneally (ip), or intracerebrally (ic) to rats burdened with the intracranial 9L gliosarcoma. The results confirm that BCNU is the most effective systemic agent among the chemotherapeutic agents tested as indicated by its ability to significantly increase the median survival time (MST) and life span of the tumor-burdened animals. Bleomycin is an effective agent against the intracranial 9L tumor when administered ic. While neither systemic single iv dose AZQ (0.5-2.5 mg/kg) nor multiple ip treatments (0.5-1.0 mg/kg x 5, q 6 h) were effective in prolonging the survival, single ic dose AZQ (5-50 micrograms/rat) treatment significantly increased the MST of the treated animals (P < 0.05). Systemic AZQ treatments using higher doses produced a hematological toxicity, resulting in a decrease in MST of the treated animals. Cis-Platinum, either administered ip or ic, produced only a marginal effect on survival, although acute neurologic toxicity limited the dose of cis-Platinum that could be administered ic. Acivicin, either administered ip or ic, produced no effect on the survival of treated animals. Our results suggest that local treatment with certain antineoplastic agents may be an efficient therapy in the management of brain tumors.

Animals↗
PubMed1992

Cochlear microphonics and recruitment.

In this study, bilateral cochlear microphonics (CM) were evoked by tone burst simultaneously. A speaker was put in head-food axis 2 m from the mid-point of a given line connecting the bilateral external meatus. Five normal persons and 68 cases (34 cases of Meniere's disease, 27 cases of sudden hearing loss, and 7 cases of low-tone sensory hearing loss without vertigo) with unilateral sensory hearing loss and recruitment, in addition to 2 cases of bilateral Meniere's disease with recruitment were examined. CM shifted in normal and hearing loss ears and was absent in profound and totally deaf ears. When recruitment was present, CM at corresponding frequencies were enlarged and prolongated in 60 cases. Some of the enlarged and prolongated CM decayed slowly, others quickly. Meanwhile the CM of the opposite normal ear decreased obviously. The presence of enlarged and prolongated CM may indicate an increase of abnormal excitability of the hair cells caused by some pathological stimulations. This would cause excitability of the hair cells in the opposite cochlea to be inhibited by the effect of the efferent system. In such a condition, the patients complained that the stimulating sound was heard louder in the disordered ear than that in the opposite normal ear. CM was slightly enlarged during sleep.

Adult↗
PubMed1992

Neurology of latent nystagmus.

We report eye movement findings in 30 patients with latent nystagmus and who were found to have a variety of associated oculomotor disorders. Latent nystagmus is defined clinically as nystagmus which appears on covering one eye and beats towards the uncovered eye. Recordings showed that the latent nystagmus in 28 patients had slow phases with linear or exponentially decreasing velocity. This nystagmus is termed 'LN'. In 13 of these patients certain manoeuvres (e.g. pursuit) provoked nystagmus with exponentially increasing slow phase velocities characteristic of the congenital form of nystagmus termed 'CN' and we propose that this is a forme fruste of CN. In two patients the nystagmus provoked by cover was latent CN. Twenty-nine patients had a history of strabismus and one had a marked phoria. Some patients had amblyopia whilst others had normal vision in each eye. Although binocular vision was usually absent, six patients had varying degrees of stereopsis. A temporonasal predominance of monocularly elicited optokinetic response previously associated with LN, was present only in a minority of patients. Some responses were bidirectionally absent or of low velocity, possibly the result of a cortical impairment of visual motion detection. The most deranged responses had slow phases which were in the opposite direction to the stimulus as described in CN. The presence of 'forme fruste' CN in many of these patients suggests that some of the derangements of optokinetic responses are due to CN. The findings indicate a greater overlap between the incidences of LN and CN than previously estimated. Thirty percent of patients had large saccadic 'square wave' intrusions. These were not present when there was marked amblyopia. They are attributed to a competitive incongruence of visual fields and eye positions. Dissociations found between the presence and severity of strabismus, stereopsis, amblyopia and optokinetic abnormalities point to these features being relatively independent although associated in typical clusterings. This is evidence against the theory that strabismus and LN are directly caused by nasotemporal optokinetic imbalance which persists because of failure to develop binocular vision. The variability of findings favours the view that LN and CN arise from a genetic or acquired embryological disorder with various degrees and directions of expression.

Adolescent↗
PubMed1992

Disseminated herpes zoster in the immunocompromised host: a comparative trial of acyclovir and vidarabine. The NIAID Collaborative Antiviral Study Group.

Seventy-three immunocompromised patients with disseminated herpes zoster were evaluated in a double-blind controlled trial of acyclovir (n = 37) versus vidarabine (n = 36) therapy. Acyclovir was administered at 30 mg/kg/day at 8-h intervals and vidarabine was given as a continuous 12-h infusion at 10 mg/kg/day for 7 days (longer if resolution of cutaneous or visceral disease was incomplete). No demographic differences existed between treatment groups. No deaths attributable to varicella-zoster virus infection occurred within 1 month of treatment. Neither rates of cutaneous healing, resolution of acute neuritis, and frequency of postherpetic neuralgia nor adverse clinical and laboratory events differed between treatment groups. Acyclovir recipients were discharged from the hospital more promptly than vidarabine recipients (P = .04, log rank test). These data indicate that disseminated herpes zoster is amenable to therapy with either acyclovir or vidarabine; resultant mortality is low.

Acyclovir↗
PubMed1992

Multiple isolates and characteristics of human T-cell leukemia virus type II.

Human T-cell leukemia (or lymphotropic) virus type II (HTLV-II) was isolated from eight HTLV-seropositive patients, six of whom were also infected with human immunodeficiency virus, by cocultivation of peripheral blood mononuclear cells (PBMCs) with BJAB, a continuous B-cell line. Restriction endonuclease mapping of the proviruses demonstrated consistent differences among isolates, and two distinct physical map patterns were observed. The results suggest the existence of two closely related molecular subtypes of HTLV-II, which are tentatively designated HTLV-IIa and HTLV-IIb. This finding was supported by preliminary nucleotide sequence analysis of the env gene region encoding the transmembrane glycoprotein gp21, which showed consistent differences between the two proposed virus subtypes. Exploitation of differences in restriction endonuclease sites allowed polymerase chain reaction amplification to detect and differentiate the two subtypes in fresh PBMCs of HTLV-seropositive intravenous drug abusers (IVDAs). The results of these studies confirm that HTLV-II infection is the prominent HTLV infection in seropositive IVDAs and also show that infection with both subtypes occurs. The finding of genetic heterogeneity in the HTLV-II group of viruses may have important implications for studies on its role in human disease and will be useful in characterizing the viruses present in newly discovered endemic foci in New World indigenous populations.

Adult↗
PubMed1992

Hypertension without peripheral insulin resistance in spontaneously hypertensive rats.

We performed euglycemic clamp studies with labeled glucose to measure insulin's effect on hepatic glucose output (HGO) and peripheral glucose clearance in eight conscious mobile spontaneously hypertensive rats (SHR) and eleven normotensive Wistar-Kyoto (WKY) rats age 9-10 wk. Systolic blood pressure was elevated in the SHR (P less than 0.001), whereas means of 12-h-fasted plasma insulin (P greater than 0.4), glucose (P greater than 0.07), HGO (P greater than 0.25), and glucose clearance (P greater than 0.2) did not differ significantly between groups. Infusions of human insulin into SHR and WKY rats (1 and 1.5 mU.min-1.kg-1, respectively) during concomitant somatostatin administration reestablished basal insulinemia in both groups. Neither HGO (P greater than 0.15) nor glucose clearance (P greater than 0.3) differed significantly between SHR and WKY rats under those conditions. Somatostatin plus higher-dose insulin infusions (4 mU.min-1.kg-1 in SHR and 3 or 6 mU.min-1.kg-1 in WKY rats) resulted in physiological hyperinsulinemia in all rats. Insulin sensitivity, calculated as the increase in glucose clearance effected by an increase in circulating insulin during higher-dose insulin infusions, did not differ significantly between SHR and WKY groups (P greater than 0.3). HGO was completely suppressed in SHR and WKY rats during the higher-dose insulin infusions. Our data indicate that hypertension is present in SHR at an age when insulin-mediated glucose disposal is not different from age-matched WKY rats. These findings do not support a role for peripheral insulin resistance in the genesis of hypertension in SHR.

Animals↗
PubMed1992

Electronystagmographic features in some peripheral and central vestibular disorders: application of multiple discriminant analysis of electronystagmographic parameters.

In routine clinical electronystagmographic (ENG) tests (postrotatory, optokinetic, caloric and tracking tests), eye movement signals were analyzed and a multiple discriminant analysis was carried out with the aid of a microcomputer. Six parameters were selected and, based on these, two functions for discriminating between peripheral and central disorders were established. Discrimination between 35 patients with peripheral lesions and 15 patients with central lesions was made with a correct classification rate of 97.1 and 86.7%, respectively. These rates are significantly higher than that of any single ENG test analysis. Our results indicate that the clinical application of ENG can be improved by searching for more sensitive ENG parameters and adopting the comprehensive analysis approach.

Adult↗
PubMed1992

17 beta-estradiol prevents osteopenia in the oophorectomized rat treated with cyclosporin-A.

Cyclosporin-A (CsA) administered to the oophorectomized rat exaggerates the high turnover osteopenia associated with oophorectomy alone. This study investigated whether 17 beta-estradiol replacement could influence the development of osteopenia in the oophorectomized rat treated with CsA. Ninety female Sprague-Dawley rats, approximately 300 g in weight, were divided into 6 groups of 15 each and treated according to the following protocol: group A were sham operated (control), group B underwent oophorectomy (Ox), group C underwent Ox and received CsA (15 mg/kg, by daily gavage) for 28 days (Ox and CsA), group D underwent Ox and received CsA and a 0.1 mg 17 beta-estradiol pellet (EP) implanted sc (Ox, CsA, and EP), group E underwent Ox and received EP (Ox and EP), and group F, which was intact and nonoperated, received CsA (CsA). Rats were weighed and bled on days -7, 0, 7, 14, 21, and 28 for measurement of blood ionized calcium, bone Gla protein (BGP), 17 beta-estradiol, and PTH. Bone histomorphometry was determined after double tetracycline labeling. On day 28, serum 17 beta-estradiol was undetectable in groups B (Ox) and C (Ox and CsA), and similar to group A (control) in groups D (Ox, CsA, and EP), E (Ox and EP), and F (CsA). Oophorectomy resulted in a significant gain in weight in groups B (Ox) and C (Ox and CsA), which was prevented by 17 beta-estradiol in groups D (Ox, CsA, and EP) and E (Ox and EP). On day 28, serum BGP levels were higher in groups B (Ox; 73.58 +/- 3.63 ng/ml), C (Ox and CsA; 85.05 +/- 9.88), and F (CsA; 81.35 +/- 3.4) compared to group A (control; 46.07 +/- 5.52; P less than 0.05), while 17 beta-estradiol in groups D (Ox, CsA, and EP; 38.65 +/- 2.85) and E (Ox and EP; 41.89 +/- 1.89) prevented this rise (P = 0.01). BGP levels in group C (Ox and CsA) were higher on days 14 and 21 compared to group B (Ox). Groups D (Ox, CsA, and EP) and E (Ox and EP) had elevated blood ionized calcium levels from day 7 onward. Serum PTH levels were unchanged. Histomorphometric analyses of tibial metaphyses revealed increased parameters of bone formation and resorption, with significant loss of bone volume, in groups B (Ox; 12.03 +/- 1.40%) and C (Ox and CsA; 11.43 +/- 2.20) vs. group A (control; 24.36 +/- 2.37; P less than 0.05).(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1992

Neuroarthropathy. Clinico-radiologic analysis of 115 cases.

115 patients (163 joints) with neuroarthropathy (Charcot joint) were observed clinically and radiologically. In Charcot joint of the shoulder, the entire scapula was disintegrated. After debridement and arthrodesis, fragmentation of bone reappeared at both ends of the affected long bone and even on the lateral surface of diaphysis. Fragmentation of the articular surface and the subchondral bone was seen in the non-weight-bearing surface. 32 patients in this series sustained spontaneous fractures without a history of trauma or undue strain. Follow-up for short periods (2 to 6 weeks) showed rapid progressive destruction. These results indicated that neurotrophic theory seems to furnish an explanation for the pathogenesis of the Charcot joint, and that bone resorption should be the primary change while bone hypertrophy and proliferation, the secondary.

Adolescent↗
PubMed1992

[Effect of the root of Polygonum multiflorum Thunb. and its processed products on fat accumulation in the liver of mice].

Experiments have shown that the root of Polygonum multiflorum exhibits inhibitory effect on triglyceride (TG) accumulation in the liver of mice induced by CCl4, cortisone acetate and thioacetamide (TAA). Its processed products (I, II) were found to be effective in lowering the accumulated TG induced by cortisone acetate. The root of Polygonum multiflorum and its processed products also reduced the enlargement of liver by CCl4.

Animals↗