Involvement of methylated HBHA expressed from Mycobacterium smegmatis in an IFN-γ release assay to aid discrimination between latent infection and active tuberculosis in BCG-vaccinated populations.

IFN-γ release assays (IGRAs) based on region of difference 1 (RD1) antigens have improved diagnosis of Mycobacterium tuberculosis (M. tb) infection. However, IGRAs with these antigens cannot discriminate between active tuberculosis (ATB) and latent tuberculosis infection (LTBI). M. tb heparin-binding-hemagglutinin (HBHA) induces relatively high IFN-γ responses in LTBI individuals and low responses in ATB patients, but purification of the native methylated HBHA from cultures of M. tb for immunological tests is complex and time-consuming. To overcome these cumbersome procedures, we constructed a recombinant Mycobacterium smegmatis strain that over-expressed HBHA under control of a strong furA promoter. The methylated activity of purified protein was verified by hybridization with anti-methylated Lys antibody, and the methylated HBHA (mHBHA) was further evaluated for antigen-specific IFN-γ responses in BCG-vaccinated Chinese population. A total of 138 individuals including 86 active TB (ATB) patients, 15 latent TB infection (LTBI) cases, and 37 healthy controls (HC) were tested by using an IFN-γ enzyme-linked immunospot (ELISPOT) assay. The results showed that T-cell responses against mHBHA were always lower in ATB patients than in LTBI individuals, regardless of the site of infection or the results of bacteriological tests. This allowed for a good discrimination between these two groups of M. tb-infected individuals, even in the BCG-vaccinated and high TB-incidence setting that is China. Additionally, combination of mHBHA and RD1 antigens in an IFN-γ release assay enhanced diagnostic efficacy for active TB cases. Taken together, inclusion of the immune response to mHBHA can discriminate healthy LTBI cases from ATB patients.

Novel coronaviruses, astroviruses, adenoviruses and circoviruses in insectivorous bats from northern China.

Bats are considered as the reservoirs of several emerging infectious disease, and novel viruses are continually found in bats all around the world. Studies conducted in southern China found that bats carried a variety of viruses. However, few studies have been conducted on bats in northern China, which harbours a diversity of endemic insectivorous bats. It is important to understand the prevalence and diversity of viruses circulating in bats in northern China. In this study, a total of 145 insectivorous bats representing six species were collected from northern China and screened with degenerate primers for viruses belonging to six families, including coronaviruses, astroviruses, hantaviruses, paramyxoviruses, adenoviruses and circoviruses. Our study found that four of the viruses screened for were positive and the overall detection rates for astroviruses, coronaviruses, adenoviruses and circoviruses in bats were 21.4%, 15.9%, 20% and 37.2%, respectively. In addition, we found that bats in northern China harboured a diversity of novel viruses. Common Serotine (Eptesicus serotinu), Fringed long-footed Myotis (Myotis fimriatus) and Peking Myotis (Myotis pequinius) were investigated in China for the first time. Our study provided new information on the ecology and phylogeny of bat-borne viruses.

Genetic epidemiology of chronic kidney disease.

PURPOSE OF REVIEW: To provide a brief review of methods used in genetic epidemiology studies, an update of recent significant findings in genome-wide studies of kidney disease, and a discussion of the clinical implications of these findings. RECENT FINDINGS: Recent developments in genetic epidemiology methodologies, specifically the use of genome-wide panels of single nucleotide polymporphisms (SNPs) for association analyses, have yielded exciting insights into the underlying pathogenesis of chronic kidney disease and its progression. The two most notable and promising genetic discoveries are those of MYH9 and UMOD, both of which have been replicated in separate populations. SUMMARY: Genomic studies have the potential to yield exciting new areas of biological research, potential targets for treatment, and ultimately markers of disease risk. This review addresses recent genetic studies and their implications in chronic kidney disease care.

Opioid-like activity in the cerebrospinal fluid of pain patients treated by electroacupuncture.

Thirteen patients with pain from various causes were treated by electroacupuncture for 30 min. Cerebrospinal fluid (CSF) was obtained before and after treatment. Opioid-like substances in the CSF were fractionated by high pressure liquid chromatography and assayed by competitive receptor binding using a mu-specific radioligand, [D-ala2, MePhe4, gly-ol5]-enkephalin (DAGO). Opioid activity, associated with a fraction, eluted at 18-20% acetonitrile, consistently showed an increase in level after acupuncture. Two other fractions eluted at larger concentrations of acetonitrile also increased significantly after acupuncture; however the increase was not consistently observed in every patient. Measurements of beta-endorphin and dynorphin by radioimmunoassay indicated that 80 and 60% of the patients, respectively, had a higher level of these peptides after acupuncture. The nature of the opioid activity, eluted at 18-20% acetonitrile is unknown; however a small amount of it could be found in various parts of the brain of rat.

Tetramethylpyrazine for treatment of experimentally induced stroke in Mongolian gerbils.

Tetramethylpyrazine, a drug originally isolated from the rhizome of Ligusticum walliichi, has been used routinely in China for the treatment of stroke and angina pectoris. We evaluated this drug by testing its effectiveness in increasing the survival rate in a stroke model using Mongolian gerbils. Our results indicate that tetramethylpyrazine can increase survival rate only if it is administered before the induction of cerebral ischemia. Since we administered the drug intraperitoneally, it is possible that pretreatment was necessary to increase its effective concentration in the blood. Receptor binding studies indicated that tetramethylpyrazine was inactive against a variety of pharmacologically active receptors.

Effect of hyperthermia on growth of Ehrlich ascites tumor cells.

Hyperthermic treatment at 43 degrees C suppressed the growth of Ehrlich ascites tumor (EAT) cells in vitro. Incubation of EAT cells at 43 degrees C for as little as 1.5 h totally abolished the transplantability of the tumor. At the same time, the rate of cellular glucose uptake, the density of glucose transporter on the cells as well as the extent of thymidine, uridine and leucine incorporation were significantly reduced.

Application of invasive microwave hyperthermia for the treatment of gliomas.

Twenty five cases of gliomas of the brain were operated upon by debulking the tumour masses. Following this, microwave hyperthermia was given by heating a measured volume of Ringer's solution instilled into the tumour cavity. This was followed by a 'dry treatment' without Ringer's solution. The follow up of these cases revealed that 11 cases have died and 14 cases are alive post-operatively. For those that are alive, the follow up period ranges from 21 to 41 months with the mean survival period of 31.1 months; in this group, 12 cases have a Kanofsky scale of 80-100, i.e. they are fully independent. The other two cases have a score of 50 or under and they need institutional care. In this study, we believe that the first order effect of microwave hyperthermia is predominantly thermal and in the published literature, and in this investigation, there is no clear evidence that microwave radiation produces any other beneficial and quantifiable effect on the tissue.

Treatment of pain in cancer patients by intrathecal administration of dynorphin.

Dynorphin-(1-13) and -(1-10) were administered by intrathecal injection into six terminal cancer patients at doses of 7.5, 15, 30 and 60 micrograms. Compared with saline, both analogues of dynorphin were effective in suppressing pain. The duration of relief at doses of 15 micrograms and above was more than 4 hours on the average for both peptides. However, no proportional increase in response was observed when the dose applied was doubled. This lack of response might have been due to the development of tolerance.

Effect of maternal methadone administration on the development of multiple forms of monoamine oxidase in rat brain and liver.

The development of total monoamine oxidase (MAO) and MAO-A and MAO-B in the forebrain, brainstem, cerebellum and liver of methadone-treated and normal rats were monitored with tryptamine, serotonin and benzylamine, respectively. Daily administration of methadone (10 mg/kg, s.c.) to pregnant and nursing rats substantially retarded the development of total and the A-form of MAO in the brain regions of pups but had no effect on that of MAO-B. The effect of methadone on the development of total MAO and MAO-A in the liver was only transient and less significant. This finding indicates that the perinatal opiate syndrome associated with maternal exposure to methadone is caused by the inhibition in MAO-A development in monoaminergic neurons in the brain.

Suppression of immunological functions in morphine addicted mice.

Lymphocytes isolated from morphine addicted mice show a number of impaired immunological functions. They include Con A stimulated mitogenesis, NK cell activity, plaque forming cell activity and delayed-type of hypersensitivity. In addition, the met-enkephalin and beta-endorphin level in the lymph nodes of addicted mice were also depressed.

Ontogenesis of multiple forms of monoamine oxidase in rat brain regions and liver.

The postnatal development of total, type-A and type-B monoamine oxidase (MAO) in the brain stem, forebrain and cerebellum, determined with preferred substrates or selective inhibitors, were found to follow different patterns. In the brain regions, MAO-A activity reached adult levels in the brain stem first, followed by the forebrain and cerebellum, while MAO-B reached adult levels in these regions at about the same time and later in postnatal life. On the other hand, both MAO-A and B activities were almost fully developed in the newborn liver. Moreover, total and type-A, but not type-B, showed a caudal-to-rostral sequence of biochemical maturation in the brain. The spatiotemporal pattern of differentiation of type-A and type-B activities in the brain tends to support the classification of brain MAO into two distinct isoenzymic forms.

Spontaneous spinal epidural haematoma.

Two Chinese patients with spontaneous spinal epidural haematoma are presented. The clinical picture and the possible site of bleeding are discussed.

Intrathecal administration of beta-endorphin and dynorphin-(1-13) for the treatment of intractable pain.

Seven cases of chronic pain were treated by intrathecal administration of 30 micrograms of beta-endorphin and dynorphin-(1-13). Compared with saline, both peptides were able to suppress pain for periods up to 4.5 and 7 hours on the average, respectively. No significant side reactions were noticed during the entire investigation.

Comparison of the effectiveness of different opioid peptides in suppressing heroin withdrawal.

The effectiveness of beta-endorphin, dynorphin-(1-13), dynorphin-(1-10) amide, alpha-neoendorphin and [D-Ala2,D-Leu5]enkephalin in suppressing withdrawal in heroin addicts was compared in this study. Groups of six patients were stabilized overnight in the hospital and were treated with either saline or peptide when withdrawal symptoms began to appear the following morning. Withdrawal was scored before and after treatment by the patient himself and an independent observer. Peptides were administered in a bolus dose of 60 micrograms/kg body weight. The patient, the observer and the physician who administered the injection were all blind to the nature of the compound given. All treatments, including those with saline, produced an overall reduction of withdrawal score. However, by statistical analysis, only treatments with beta-endorphin, [D-Ala2,D-Leu5]enkephalin and dynorphin-(1-13) were effective in producing a significant decrease of withdrawal symptoms. The length of relief brought about by the different peptides varied from less than an hour to a maximum of 5 h in one case. The average period of relief brought about by beta-endorphin, dynorphin-(1-13) and [D-Ala2,D-Leu5]enkephalin was 44, 46 and 60 min, respectively. Of the five peptides administered [D-Ala2,D-Leu5]enkephalin produced the largest number of side-effects.

Cerebrospinal fluid [Met5]enkephalin level in schizophrenics during treatment with naloxone.

The effect of naloxone on CSF [Met5]enkephalin level and on the suppression of psychotic symptoms associated with schizophrenia was studied. Seven patients were treated with naloxone at a dose of 0.4 mg/day for seven days and six were treated with saline for the same period. Of the seven patients receiving naloxone, three showed signs of improvement. In the saline group, only one case of obvious improvement was observed. The mean CSF [Met5]enkephalin level before and after treatment in both the naloxone and saline group did not change significantly. However, there was a highly significant correlation (r = -0.73, P less than 0.01) between the increase of [Met5]enkephalin level and the decrease in psychotic symptoms.