PubMed Health⌕ Search

Biomedical subjects

L F Luo

Publications and source records attributed to L F Luo.

11 recordsLinked to original sources

Macronodular multi-organs tuberculoma: CT and MR appearances.

The case of a 21-year-old woman presenting with macronodular multi-organs tuberculoma is reported. She was examined for pulmonary tuberculosis on a chest X-ray film in January, 1995, and admitted with a cough, anorexia, and abdominal pain in July, 1996. Computed tomography revealed multiple calcified nodules with peripheral hypodense areas in the brain, and calcified hypodense masses in the liver and spleen. Magnetic resonance (MR) imaging showed hypointense masses in the liver and spleen on T1-weighted spin echo images and a hypointense mass with a hyperintense area on T2-weighted spin echo images. On contrast-enhanced dynamic MR images, the liver and spleen masses were unenhanced and hypointense with slight rim enhancement. T2-weighted spin echo images showed a round hypointense nodule in the right kidney and hydronephrosis and enlargement in the left kidney. Antituberculous treatment was started with a gradual improvement in her signs and symptoms. Her temperature became normal. However, she was systemically treated with antituberculous chemotherapy 10 months later, her condition worsened again. She died from increased intracranial pressure in August, 1997.

Adult↗

[Efficacy of ivermectin for control of microfilaremia recurring after treatment with diethylcarbamazine: immunological observation].

We compared the effect of a single dose of ivermectin (100 micrograms/kg) with that of a standard course of diethylcarbamazine (DEC) (6 mg/kg) on several parameters of the host's antifilarial immune response in 60 patients with bancroftian filariasis enrolled in a double-blind drug trial. All participants had measurable serum levels of antifilarial antibodies and parasite antigens. Drug-induced clearance of microfilaremia was associated with a temporary increase in HC11 antigenemia and a decrease in serum levels of antibodies to soluble filarial antigens. Antigenemia progressively declined in patients who remained a microfilaremic after treatment, but declined and then rose in persons with recurrent microfilaremia. Treatment triggered a sustained increase in serum levels of IL-1, IL-6, TNF alpha and IFN gamma in all patients. Although Ivermectin and DEC are believed to exert their antiparasite activity via different mechanisms, the same pattern of serological changes was observed in patients treated with either drug.

Animals↗

[Efficacy of ivermectin for control of microfilaremia recurring after treatment with diethylcarbamazine. I. Clinical and parasitological observations].

We compared the efficacy of a single dose of ivermectin with that of a standard course of deithylcarbamazine (DEC) for the control of microfilaremia in 60 patients with banrroftian filariasis who had developed recurrent microfilaremia after each of three or more prior treatments with DEC. The study was done as a randomized, double-blind trial. Complete, but transient clearance of microfilaremia was observed in both treatment groups. One year later, recurrent microfilaremia was present in 7 patients treated with ivermectin and in 5 treated with DEC. Pretreatment levels of microfilaremia were significantly higher in patients who relapsed within one year after treatment than in those who remained amicrofilaremia. Side effects of either treatment were common but mild. Febrile reactions were more frequent in the ivermectin group: while localized reactions consistent with a flare up of acute filarial disease occurred mostly in the DEC group. We conclude that ivermectin is an effective and practical alternative to DEC for treatment of recurrent microfilaremia due to bancroftian filariasis.

Adolescent↗

The statistical correlation of nucleotides in protein-coding DNA sequences.

The statistical correlation of nucleotides in a DNA sequence is described by a set of redundancies D1, D2, D3, . . . . By calculation of [Dn] of 2341 coding regions of nucleic acid sequences it is demonstrated that about 2/3 of sequences has correlation length less than or equal to 2, 10% of sequences--correlation with 3-periodicity and others--long range aperiodic correlations. The implications of the results from the interactions of random mutation and natural selection are discussed briefly.

Base Sequence↗

Efficacy of ivermectin for control of microfilaremia recurring after treatment with diethylcarbamazine. I. Clinical and parasitologic observations.

We compared the efficacy of a single dose of ivermectin with that of a standard course of diethylcarbamazine (DEC) for the control of microfilaremia in 60 patients with bancroftian filariasis who had developed recurrent microfilaremia after each of three or more prior treatments with DEC. The study was done as a randomized, double-blind trial. Complete, but in some cases, transient clearance of microfilaremia was observed in both treatment groups. At one year, recurrent microfilaremia was present in seven patients treated with ivermectin and in five treated with DEC. Pretreatment levels of microfilaremia were significantly higher in patients who relapsed within one year after treatment than in those who remained amicrofilaremic. Side effects with both treatments were common, but mild. Febrile reactions were more frequent in the ivermectin group; localized reactions consistent with a flare-up of acute filarial disease occurred mostly in the DEC group. We conclude that ivermectin is an effective and practical alternative to DEC for treatment of recurrent microfilaremia due to bancroftian filariasis.

Adolescent↗

Efficacy of ivermectin for control of microfilaremia recurring after treatment with diethylcarbamazine. II. Immunologic changes following treatment.

We compared the effect of a single dose of ivermectin with that of a standard course of diethylcarbamazine (DEC) on several parameters of the host's antifilarial immune response in 60 patients with bancroftian filariasis enrolled in a double-blind drug trial. All participants had measurable serum levels of antifilarial antibodies and parasite antigens at the onset of the study. Drug-induced clearance of microfilaremia was associated with a temporary increase in HC 11 antigenemia and a decrease in serum levels of antibodies to soluble filarial antigens. Antigenemia progressively declined in patients who remained amicrofilaremic after treatment, but declined and then increased in persons with recurrent microfilaremia. Treatment triggered a sustained increase in serum levels of interleukin-1, tumor necrosis factor, and interleukin-6 in all patients studied. Although ivermectin and DEC are believed to exert their antiparasite activity via different mechanisms, the same pattern of serologic changes was observed in patients treated with either drug.

Adolescent↗

A statistical theory of amino acid mutation.

Assuming that the observed mutation frequency of an amino acid depends on two factors. The first is mutation coefficient which describes the rate of the nucleotide substitution stochastically and the second is the similarity of amino acids which represents the fitness of a mutant under the selective pressure. A statistical theory is proposed and 380 mutation frequencies are calculated, only 10 of which disagree obviously with the observed data.

Amino Acids↗

The distribution of amino acids in the genetic code.

By introducing a mutational deterioration function MD and a principle of approximate minimum of the function, we have deduced the distribution of amino acids in genetic code, which includes the degeneracy rule of codons, the global extreme of genetic code from codon interactions and the hydrophobicity domain of the prevalent (standard) code.

Amino Acids↗

Informational parameters of nucleic acid and molecular evolution.

From the point of view of information theory, a statistical analysis of 2000 nucleic acid sequences (732 coding regions and 1177 non-coding regions) is given. The sequences are grouped into 20 categories. The probability-order-difference (POD) matrix is defined which is used to analyse the evolutionary distance of any two categories of sequences. The informational parameters D1, D2 and X = (1 + D1/D2)-1 and F are calculated for each sequence and averaged in each category. The statistical dependence of these parameters on molecular evolution is discussed. It is found that [X] is a good statistical quantity which describes the vocabulary compositions as well as the grammatical constructions of the genetic language. From the statistical analysis it is shown that [X] may play an important role in investigating the evolutionary level of nucleic acid molecules.

Base Sequence↗

The degeneracy rule of genetic code.

The degeneracy rules of genetic code including the distribution of terminators have been deduced through the minimization of mutational deterioration (MD). The MD of a given group of codons is divided into three parts: transitional, transversional and wobble's. The averaged mutational deteriorations (AMD) of various amino acids have been proved in order of their degrees of irreplaceability.

Amino Acids↗