Hyperbaric oxygen therapy increases the risk of tuberculosis disease.

BACKGROUND: As Mycobacterium tuberculosis is an aerobic microbe, hyperbaric oxygen therapy (HBOT) could trigger progression from latent tuberculous infection (LTBI) to active tuberculosis (TB) disease. OBJECTIVE: To evaluate the effect of HBOT on TB reactivation. DESIGN: Our study sample was from the National Health Insurance Research Database containing one million beneficiaries. We identified a group of patients who underwent HBOT, and matched this group with individuals without HBOT. We compared the incidence of activation of TB between these two groups. RESULTS: A total of 2258 patients were identified, with each group comprising 1129 patients. One year after exposure to hyperbaric oxygen, the number of cases of active TB was significantly higher in the HBOT group than in the non-HBOT group (11 cases vs. 1 case, P = 0.006). Multiple regression analysis showed that HBOT was the only statistically significant contributor to TB activation. CONCLUSION: HBOT is likely to trigger the reactivation of TB. High-risk patients should undergo the tuberculin skin test or interferon-gamma release assays before HBOT to identify patients with LTBI.

Electro-acupuncture at ST37 and ST25 induce different effects on colonic motility via the enteric nervous system by affecting excitatory and inhibitory neurons.

BACKGROUND: On the basis of the importance of the enteric nervous system (ENS) in gastrointestinal motility, we hypothesized that the ENS may mediate the therapeutic efficacy of electro-acupuncture (EA) in constipation by regulating the mechanisms underlying the effects of EA on gastrointestinal function. METHODS: Model mice with constipation were generated by gastric instillation of 0-4°C normal saline. Defecation time and stool (form and wet and dry weight) were assessed. The effect of EA at ST37 or ST25 on colorectal motility and proximal colonic motility was assessed using a water-filled balloon. The expression of protein gene product 9.5 (PGP9.5), the cholinergic neuron marker acetyltransferase (ChAT) and the anticholinergic neuron marker nitric oxide synthase (nNOS) was detected by immunohistochemistry, real-time quantitative polymerase chain reaction (qPCR) and western blot analysis. KEY RESULTS: ST37 and ST25 improved colorectal pressure; however, ST37 but not ST25 improved proximal colonic pressure. In the proximal colon, the expression of PGP9.5 returned to normal after EA at ST 37, while EA at ST25 did not have this effect. In addition, qPCR and western blot analysis showed that ST37 could downregulate the expression of nNOS and upregulate the expression of ChAT to normal levels, while ST25 could only downregulate the expression of nNOS to normal levels. CONCLUSIONS AND INFERENCES: Electro-acupuncture at specific acupoints can improve intestinal motility in constipation by altering the ENS and differentially affecting excitatory and inhibitory neurons, restoring the coordination between contraction and relaxation muscles, and working in concert with the central nervous system and peripheral neural pathways.

Effect of supplementation of organic manganese on reproductive performance of female Ussuri raccoon dogs (Nyctereutes procyonoides) during the breeding season.

The study was conducted to investigate the effect of dietary manganese (Mn) on reproductive performance of female Ussuri raccoon dogs (Nyctereutes procyonoides) during the breeding season. Healthy female Ussuri raccoon dogs (n=72) were randomly divided into six groups of twelve each. The six experimental diets were formulated to contain graded amounts of Mn (0, 40, 80, 120, 200 and 400mg/kg of diet; Groups A through F, respectively). Litter size of Group D was greater than that of Groups A, B, C and E (P<0.05), with Group E having the smallest litter size. Values of number born alive were affected by different amounts of organic Mn. Number of pups born alive in Group D was greater than that of Groups B, C, E and F (P<0.05). Number of pups weaned alive for Group D was greater than that of Groups A, B, C and E (P<0.05). Mn supplementation of the control diet (containing 24.32 mg/kg from raw materials) with 120 mg/kg of Mn was adequate for female Ussuri raccoon dogs during the breeding season, based on positive effects of reproduction performance.

A 90-day subchronic toxicity study of neem oil, a Azadirachta indica oil, in mice.

To determine the no-observed-adverse-effect level (NOAEL) of exposure and target organs of neem oil for establishing safety criteria for human exposure, the subchronic toxicity study with neem oil in mice was evaluated. The mice (10 per sex for each dose) was orally administered with neem oil with the doses of 0 (to serve as a control), 177, 533 and 1600 mg/kg/day for 90 days. After the treatment period, observation of reversibility or persistence of any toxic effects, mice were continuously fed without treatment for the following 30 days. During the two test periods, the serum biochemistry, organ weight and histopathology were examined. The results showed that the serum biochemistry and organ coefficient in experimental groups had no statistical difference compared with those of the control group. At the 90th day, the histopathological examinations showed that the 1600 mg/kg/day dose of neem oil had varying degrees of damage on each organ except heart, uterus and ovarian. After 30-day recovery, the degree of lesions to the tissues was lessened or even restored. The NOAEL of neem oil was 177 mg/kg/day for mice and the target organs of neem oil were determined to be testicle, liver and kidneys.

The pathology of selenium deficiency in Cyprinus carpio L.

Selenium is essential for the normal life processes, and all animals, including fish, need this inorganic element. In order to research the pathology of selenium deficiency in common carp, Cyprinus carpio L., 360 juvenile carp were allocated to three treatments. Each treatment containing 120 fish was randomly divided into four groups, fed with purified diets containing selenium at 0, 0.15, 0.30 and 0.45 mg kg(-1). The results indicated that the morbidity and mortality rates of the test groups were negatively correlated with the level of selenium in the diets. The morbidity and mortality rates were, respectively, 46.7%, 33.3%, 13.3%, 0 and 26.7% 16.7%, 6.7%, 0. The affected fish exhibited pathological changes, such as 'thin back disease' and lordosis. Histologically, there was no abnormality observed in muscles, liver and pancreas. Ultrastructurally, there was swelling of the mitochondria of the cardiac muscle cells, the liver cells and renal tubular epithelial cells, with disintegration and lysis of the cristae of the mitochondria which vesiculated. Serum glutamic oxaloacetic transaminase and glutamic pyruvic transaminase levels were increased and the activity of the serum glutathione peroxidase and the serum superoxide dismutase was decreased; in contrast, the serum malonaldehyde concentration was increased.

A standardized extract of Ginkgo biloba suppresses doxorubicin-induced oxidative stress and p53-mediated mitochondrial apoptosis in rat testes.

BACKGROUND AND PURPOSE: Doxorubicin evokes oxidative stress and precipitates cell apoptosis in testicular tissues. The aim of this study was to investigate whether the Ginkgo biloba extract 761 (EGb), a widely used herbal medicine with potent anti-oxidant and anti-apoptotic properties, could protect testes from such doxorubicin injury. EXPERIMENTAL APPROACH: Sprague-Dawley male rats (8 weeks old) were given vehicle, doxorubicin alone (3 mg kg(-1) every 2 days for three doses), EGb alone (5 mg kg(-1) every 2 days for three doses), or EGb followed by doxorubicin (each dose administered 1 day after EGb). At 7 days after the first drug treatment oxidative and apoptotic testicular toxicity was evaluated by biochemical, histological and flow cytometric analyses. KEY RESULTS: Compared with controls, testes from doxorubicin-treated rats displayed impaired spermatogenesis, depleted haploid germ cell subpopulations, increased lipid peroxidation products (malondialdehyde), depressed antioxidant enzyme activities (superoxide dismutase, glutathione peroxidase and glutathione), reduced antioxidant enzyme expression (superoxide dismutase) and elevated apoptotic indexes (pro-apoptotic modulation of Bcl-2 family proteins, intensification of p53 and Apaf-1, release of mitochondrial cytochrome c, activation of caspase-3 and increase of terminal deoxynucleotidyl transferase nick-end labelling/sub-haploid cells), while EGb pretreatment effectively alleviated all of these doxorubicin-induced abnormalities in testes. CONCLUSIONS AND IMPLICATIONS: These results demonstrate that EGb protected against the oxidative and apoptotic actions of doxorubicin on testes. EGb may be a promising adjuvant therapy medicine, potentially ameliorating testicular toxicity of this anti-neoplastic agent in clinical practice.

Clock and ATF4 transcription system regulates drug resistance in human cancer cell lines.

The mechanisms underlying cellular drug resistance have been extensively studied, but little is known about its regulation. We have previously reported that activating transcription factor 4 (ATF4) is upregulated in cisplatin-resistant cells and plays a role in cisplatin resistance. Here, we find out a novel relationship between the circadian transcription factor Clock and drug resistance. Clock drives the periodical expression of many genes that regulate hormone release, cell division, sleep-awake cycle and tumor growth. We demonstrate that ATF4 is a direct target of Clock, and that Clock is overexpressed in cisplatin-resistant cells. Furthermore, Clock expression significantly correlates with cisplatin sensitivity, and that the downregulation of either Clock or ATF4 confers sensitivity of A549 cells to cisplatin and etoposide. Notably, ATF4-overexpressing cells show multidrug resistance and marked elevation of intracellular glutathione. The microarray study reveals that genes for glutathione metabolism are generally downregulated by the knockdown of ATF4 expression. These results suggest that the Clock and ATF4 transcription system might play an important role in multidrug resistance through glutathione-dependent redox system, and also indicate that physiological potentials of Clock-controlled redox system might be important to better understand the oxidative stress-associated disorders including cancer and systemic chronotherapy.

Molecular-replacement studies of Trichosanthes kirilowii lectin 1: a structure belonging to the family of type 2 ribosome-inactivating proteins.

Trichosanthes kirilowii lectin 1 (TKL-1) isolated from the tuber of T. kirilowii consists of two chains, each with a molecular weight of about 30 kDa. It has immunological properties which are similar to some ribosome-inactivating proteins (RIPs). TKL-1 was crystallized in space group P2(1)2(1)2(1) and diffraction data were collected to 2.7 A resolution. The molecular-replacement method was applied to solve the structure, using different chains of ricin, abrin-a and trichosanthin as search models. A set of consistent solutions was further verified by R(omit) profile analysis. In addition, the spatial arrangement of the two chains of TKL-1 is identical to that of type 2 RIPs.

Protein crystal growth in microgravity using a liquid/liquid diffusion method.

Crystallization of proteins by liquid liquid diffusion method was performed in microgravity using the MDA Minilab aboard the US Space Shuttle. Three proteins, namely lysozyme, trichosanthin, and a new lechin, were crystallized in the space experiment. In contrast to the results of space experiments with a tube-like vapor diffusion method, the crystallization conditions for growing better crystals in space are remarkably different from the conditions optimized on earth. This may be due to difficulties in ground optimization, which are caused by gravity-dependent phenomena, in particular the specific convective flow occurring with liquid liquid diffusion.

[Cation channels formed in lipid bilayer by Pinellia ternata lectin].

Pinellia ternata lectin (PTL), a protein exhibiting hemagglutination activity and carbohydrate binding specificity to mannan was purified from rhizome of Pinellia ternata. In this work the actions of PTL on artificial lipid bilayer were investigated by means of the two-compartment system of Mueller and Rudin. The lipid bilayer with resistance more than 10G omega was formed by a solution of lecithin and cholesterol (20 mg/ml and 5 mg/ml respectively) in N-decane. The electrical properties of the lipid bilayer were investigated in voltage clamp mode. Several minutes after the addition of PTL (2 micrograms/ml) in one compartment the channel-like noise as well as a decrease of the resistance of the bilayer were observed. These actions were inhibited by mannan significantly. The resistance increase of the bilayer with PTL-channels could be observed from 2G omega to control level (greater than or equal to 10 G omega) immediately after addition of 40 micrograms/ml mannan. The discrete conduction steps were recorded at low concentration of PTL and at low holding potential. The predominant unit conductance was 35pS in symmetric KCl solution of 100 mmol/L. The selectivity of PTL-channel was estimated from Goldman-Hodgkin-Katz equation by measurement of the reversal potential in an asymmetrical salt solution. The results showed that PTL-channels were cation selective.