[Study on the relationship between HIV drug resistance and CD4(+)T cell counts among antiretroviral therapy patients with low viral load].

Objective: To explore drug resistance of different viral loads, and investigate the relationship between drug resistance and CD4(+)T cell counts in patients with HIV antiretroviral therapy (ART) in China from 2003 to 2015. Methods: Data were extracted from the Chinese National HIVDR Surveillance database from 2003 to 2015. For this study, the data collected were as follows: having received ART for ≥12 months; 18 years or older; demographic characteristics, information of ART, CD4(+)T cell counts, viral load (VL) and HIV drug resistance of a total of 8 362 patients were collected. Multi-variables non-conditional logistic regression model was used to study the relationship between viral load, HIV drug resistance and CD4(+)T cell counts. Results: Participants with age of (41.8±10.5) years were enrolled in this study. Among them, 59.9% (5 009 cases) were men. The percentage of CD4(+)T cell counts <200 cells/µl in the total population was 17.9% (1 496 cases), the highest was in VL ≥1 000 copies/ml with drug resistance, which was 43.0% (397/923) , followed by VL 50-999 copies/ml with drug resistance, which was 31.1% (69/222), and the lowest was in VL 50-999 copies/ml without drug resistance 13.2% (273/2 068). Compared to VL 50-999 copies/ml without drug resistance, VL<50 copies/ml, VL 50-999 with drug resistance, VL≥1 000 copies/ml without drug resistance, and VL ≥1 000 copies/ml with drug resistance, the OR (95%CI) of CD4 <200 cells/µl were 0.9 (0.7-1.0), 3.2 (2.3-4.4), 2.6 (2.1-3.2), and 4.9 (4.0-5.9), respectively. Among 222 patients with VL 50-999 and HIVDR, the most frequent antiretroviral drugs were EFV and NVP, both of which were NNRTI, and whose percentage both were 94.1% (209 cases). The most frequent mutations were M184V/I (NNRTI), and the percentage was 26.1% (58 cases). The second one was K103N (NNRTI), and the percentage was 22.5% (50 cases). The percentage of V32L/E (PI) and V82A (PI) were lower, they were 0.9% (2 cases) and 0.5% (1 case) respectively. Conclusion: Decreased CD4(+)T cell counts were associated with HIV drug resistance at low viraemia. In the case of low viral load, the most vulnerable were the NNRTI antiviral drugs such as EFV and NVP.

Treatment of aggressive angiomyxoma with aromatase inhibitor prior to surgical resection.

Aggressive angiomyxoma (AA) is a rare, locally infiltrating soft tissue tumor typically located in the genital tract of young, reproductive age women. Surgical excision has been the mainstay of treatment. Recently, gonadotropin-releasing hormone agonist therapy has been reported to decrease the size of estrogen-receptor positive AA. We present the first case of a postmenopausal woman treated with an aromatase inhibitor to shrink the size of tumor prior to surgical resection.

B-type natriuretic peptide in the management of heart failure.

OBJECTIVE: To review the current literature on the use of B-type natriuretic peptide in the diagnosis and management of heart failure. DATA SOURCES: Literature search of PubMed was performed up to September 2007. STUDY SELECTION: Key words for the literature search were 'heart failure' and 'B-type natriuretic peptide'. DATA EXTRACTION: Original papers and review articles related to the use of B-type natriuretic peptide in the diagnosis and management of heart failure. DATA SYNTHESIS: Heart failure is common in Hong Kong, and is associated with significant morbidity and mortality. Heart failure is often misdiagnosed. B-type natriuretic peptide may be regarded as a quantitative marker of heart failure; its levels have good diagnostic accuracy and can be measured with a rapid and simple bed-side assay and are useful in the assessment of patients with acute dyspnoea. Factors, such as obesity and renal impairment, alter B-type natriuretic peptide levels. Measurement of B-type natriuretic peptide facilitates improved medical outcomes, is cost-effective, and constitutes a good prognostic indicator for death and cardiac events. CONCLUSIONS: Determination of B-type natriuretic peptide levels is useful in the assessment of patients with acute dyspnoea, to exclude or diagnose heart failure, to facilitate improved medical outcomes, and is cost-effective. In addition, it is a good long-term prognostic indicator and can be used to guide heart failure treatment.

Remifentanil on T lymphocytes, cognitive function and inflammatory cytokines of patients undergoing radical surgery for cervical cancer.

OBJECTIVE: To explore the effects of remifentanil on cognitive function, T lymphocyte subsets and inflammatory cytokines of patients undergoing radical surgery for cervical cancer. PATIENTS AND METHODS: A total of 70 patients undergoing radical surgery for cervical cancer in our hospital from August 2014 to January 2017 were selected. They were divided into control group (n=35) and experimental group (n=35). The patients in the control group received intravenous drip of fentanyl, while those in the experimental group received intravenous drip of remifentanil in the surgery. All the patients returned to the wards after surgery. The eye-opening time, extubation time and awaking time of the patients were collected and recorded by specialized surgical nurses. Moreover, the cognitive function of the patients was assessed at the beginning of the surgery and 3 h, 6 h, 12 h, and 24 h after surgery. Blood was drawn at 24 h after surgery, and quantitative analysis of T lymphocyte subsets and inflammatory cytokines of the patients was conducted. RESULTS: The eye-opening time, extubation time, and awaking time in the remifentanil group were significantly earlier than those in the fentanyl group after surgery (p<0.05). At the same time after surgery, the score of mini-mental state examination (MMSE) in the remifentanil group was higher than that in the fentanyl group. The difference was statistically significant (p<0.05). The patients in the experimental group had a relatively low occurrence of cognitive disorder after surgery (p<0.05). The impacts of remifentanil on each type of T lymphocytes and inflammatory cytokines of the patients after surgery were smaller than those of fentanyl. The differences were statistically significant (p<0.05). CONCLUSIONS: Remifentanil can wake patients up early after surgery. Meanwhile, it results in small inflammatory response and stress response, and low occurrence of postoperative cognitive dysfunction in patients. Therefore, it is worthy of being vigorously promoted for clinical application.

Nonvolatile memory devices with NiSi2/CoSi2 nanocrystals.

Metal-oxide-semiconductor structures with NiSi2 and CoSi2 nanocrystals embedded in the SiO2 layer have been fabricated. A pronounced capacitance-voltage hysteresis was observed with a memory window about 1 V under low programming voltage. The retention characteristic can be improved by using HfO2 layer as control oxide. The processing of the structure is compatible with the current manufacturing technology of semiconductor industry.

Industrial wideband noise reduction for hearing aids using a headset with adaptive-feedback active noise cancellation.

High-intensity noises are a health hazard for industrial workers, and hearing protection is necessary to prevent hearing loss. Passive methods, such as ear muffs, are ineffective against low-frequency noise. Moreover, many hearing-impaired workers must wear hearing aids to enable communication at their workplace, and such aids can amplify ambient noise. To overcome this problem, the present study developed a headset equipped with a digital signal processing system to implement adaptive-feedback active noise cancellation (AFANC) to reduce low-frequency noise. The proposed AFANC headset was effective against wideband industrial noise, with a maximum noise spectrum power reduction of 30 dB. Furthermore, when used with a hearing aid, it improved the speech signal-to-noise ratio by up to 14 dB. These results suggest that a headset with AFANC would be useful for hearing protection in workplaces with high levels of low-frequency industrial noise, especially for hearing-impaired workers.

Effects of ether anaesthesia and fasting on various cytochromes P450 of rat liver and kidney.

Fed and fasted, male, Wistar albino rats exposed to light ether anaesthesia and killed immediately or after 30 or 120 min recovery were compared with non-anaesthetized rats for changes in liver and kidney cytochrome P450 (CYP) activities. In fed rats, liver total CYP (nmol/mg protein) decreased by 30% immediately after ether, but was restored to normal levels after 30 min recovery; in fasted rats, liver total CYP increased by 20% by fasting alone, then decreased by 65% immediately after ether, and recovered to only 70% of control at 2 hr after ether. Rat liver cytochrome P4501A (CYP1A; 7-ethoxyresorufin O-deethylase or EROD activity) and cytochrome P4502B (CYP2B; 7-pentoxyresorufin O-dealkylase or PROD activity) were decreased after ether anaesthesia, similar to those for total CYP. In contrast, rat liver cytochrome P4502E1 (CYP2E1), determined by p-nitrophenol hydroxylation, increased by 40% by ether anaesthesia alone, 70% by fasting alone and 140% by ether plus fasting; these increases were confirmed by the CYP2E1-mediated activation of nitrosopyrrolidine and by immunoblot analysis using antibody to CYP2E1. In rat kidney, losses of total CYP, CYP1A and CYP2B, and increases of CYP2E1, induced by ether anaesthesia, were much more marked in fasted (90% loss in total CYP, 30% increase in CYP2E1) than in fed rats (slight loss in total cytochrome P450, 30% increase in CYP2E1). As maximum losses of total CYP in liver of fasted rats exposed to ether occurred at the time of maximum increase of CYP2E1 and maximum rate of generation of reactive oxygen species (ROS), it is suggested that the increase of CYP2E1, resulting from its stabilization by fasting and ether, leads to generation of ROS, increase in lipid peroxidation and consequent loss of total CYP, associated with the hepatic and renal necrosis seen in ether intoxication and surgical trauma.

The effects of ether anaesthesia on oxidative stress in rats--dose response.

Rats, with and without overnight fasting, were anaesthetised for 5, 15 and 30 min with diethyl ether, killed immediately and total glutathione (total GS), thiobarbituric acid-reacting substances (TBAR), radical-trapping activity (RTA), total cytochrome P450 (CYP), and 7-ethoxyresorufin O-deethylase (CYP1), 7-pentoxyresorufin O-dealkylase (CYP2B) and 4-nitrophenol hydroxylase (CYP2E1) activities of liver and kidney determined. Liver, after ether anaesthesia, but no fasting, showed 30-60% losses of total GS, RTA, and total CYP, after 5, 15 and 30 min of anaesthesia, while TBAR increased 10-, 20- and 35-fold for the same periods. Liver after ether anaesthesia and overnight fasting showed 50-85% losses of total GS, RTA and total CYP, for 0, 5, 15 and 30 min of anaesthesia, while TBAR increased 4-, 30-, 40- and 60-fold for the same periods of anaesthesia. Kidney changes were similar to those in liver. Liver CYP1 and CYP2B were decreased by 45% and 35%, respectively for 30 min of anaesthesia in fed rats, and by 80% and 30% respectively for 30 min of anaesthesia in fasted rats; in contrast, liver CYP2E1 was increased 30% by fasting alone and 70% by fasting plus 5 min of ether anaesthesia. Kidney CYP1 and CYP2B were similarly decreased by ether anaesthesia (70% and 50% respectively) in both fed and fasted rats, and CYP2E1 was similarly increased (by 40-90% in fed and 30-110% in fasted rats). The decrease in tissue total GS, RTA, total CYP, CYP1 and CYP2B, and the increase in lipid peroxidation products (TBAR), are all considered to be due to generation of reactive oxygen species and oxidative stress, associated with the increase in CYP2E1 activity that results from both fasting and exposure to diethyl ether.

Comparative toxicity and biotransformation of lindane in C57BL/6 and DBA/2 mice.

DBA/2 mice, previously identified as "unresponsive" to aromatic hydrocarbons which induce microsomal enzymes in C57BL/6 mice, are more vulnerable to the convulsant effect of repeated doses of lindane than similarly treated C57BL/6 mice. Death in convulsions and higher blood and brain lindane concentrations indicate that less efficient disposition of lindane itself accounts for the greater vulnerability of the DBA/2 mice. The same two principal chlorophenolic metabolites of lindane were identified in the blood and tissues of both strains, but the time-courses of blood concentrations in response to repeated lindane dosing were different.

Postpartum cell-mediated immunity induced in the rat following perinatal exposure to iodine-131.

Studies were undertaken with the intent to establish the degree of risk experienced by a mother and her immediate offspring in developing gastrointestinal cancer following exposure to iodine-131 during pregnancy. An indirect approach in the identification of tumor induction for risk determination was utilized in this study which relied upon the measurement of antitumor cell-mediated immunity (CMI) occurring in the host following exposure to the radionuclide. Fischer F344 inbred pregnant rats were selected as the animal model, and the radionuclide exposure was accomplished by a single intraperitoneal administration of iodine-131 [Na131] at the stage of 16-18 days of pregnancy; then at two months postpartum, the dams and pups were evaluated for the capacity of their peripheral blood lymphoid cells to express specific cytotoxic responses towards target cells consisting of cultured X-ray induced rat small bowel adenocarcinoma cells. The results indicate that an antitumor immunity was induced in the pups upon such a prenatal exposure, while none could be detected existing in their mothers. In addition, there appeared to be a possible sex or hormonal component as a preliminary consideration of the data suggested the male offspring were approximately 1.7 times more immunoresponsive to the perinatal insult. Threshold detection level for detecting such responses to the iodine-131 was found to be in the range of a 9.25 kBq (250 nCi) quantity of exposure. The implication of these preliminary findings based upon such indirect measurements is that the first generation may be at an increased risk to gastrointestinal cancer following peritanal exposure to iodine-131 in the later stage of pregnancy.

Number of animals for sequential testing.

US regulatory agencies have used six animals in eye irritation tests. Analyses of eye irritation tests on pesticides (n = 48), consumer products and cosmetics (n = 53), Marzulli and Ruggles database (n = 139), and cleaning products and ingredients (n = 30) have greatly extended previous investigations of the merit of reducing animal sample size in the eye test. Given the existing scoring system for positive animal responses (corneal opacity > or = 1, iritis > or = 1, conjunctival redness > or = 2 and conjunctival chemosis > or = 2), the accuracy of the classification systems currently used by these agencies was determined. The US Consumer Product Safety Commission, US Food and Drug Administration, and US Occupational Safety and Health Administration use a classification system by which a substance is designated as an irritant when at least four of six animals give a positive response. This decision rule leads to a very high accuracy of at least 99% with essentially no false positive and false negative judgments. In contrast, the system used by the US Environmental Protection Agency pesticide program, in which only one or more of six treated animals result in an irritant decision, has an accuracy of only 50-80% with very high false positive rates. Analyses indicated that test sample size could be reduced to three and still preserve very good accuracy, whereas two-animal and one-animal tests did not give satisfactory responses. A two-stage test, in which two animals are tested and evaluated in the first stage before the need for testing one more animal in the second stage is determined, also demonstrated good operating characteristics. Both the one-stage/three-animal test and the two-stage test deserve consideration.

Scoring for eye irritation tests.

Scoring of the rabbit eye test and the resulting evaluation and classification should provide useful information about the likelihood that a test material may cause injury on contact with the human eye. When an animal test is necessary, a rabbit eye test based on the following characteristics is proposed for deriving the maximum information from the fewest animals. The ocular effects of interest should include corneal opacity, iritis and conjunctival redness. Animals should be scored for each ocular effect at 24, 48 and 72 hr after the test substance is administered. If an animal is negative at all three scoring times, it can be removed from the test at 72 hr. If it shows a positive effect at a scoring time but the lesion clears at 72 hr, it can be removed at 72 hr. If it shows a positive effect that does not clear at 72 hr, it should be scored again on day 7 when the test ends. However, if an animal shows severe effects at one or more scoring times, it can be removed from the test at 72 hr. An animal is positive if any one of the following criteria is observed at 24, 48 or 72 hr: corneal opacity of 1 or above, iritis of 1 or above, or conjunctival redness of 2 or above. Severe ocular effects (noted at 24, 48 or 72 hr) that may endanger sight deserve special recognition for the classification of chemicals and include corneal opacity of 3 or above, or iritis of 2. This proposal is consistent with the opinions of the majority of respondents who attended the Workshop on Updating Eye Irritation Test Methods, Proposals for Regulatory Consensus. The most notable exception was the suggestion by respondents to add conjunctival chemosis as one of the scoring parameters.

An eye irritation test protocol and an evaluation and classification system.

An in vivo test protocol and an evaluation and classification system for the determination of eye irritation potential of chemicals and mixtures (substances) is proposed. The protocol uses two or three rabbits and reduces distress in test animals. The test substances are classified as non-irritant, irritant or severe irritant to meet regulatory needs. They may be classified on the basis of past experience with similar compounds or mixtures. Screens such as structure-activity relationships, pH extremes, validated and accepted in vitro tests, severe dermal irritation (primary dermal irritation index > or = 5) or severe dermal toxicity (lethality at < 200 mg/kg body weight) should be used to classify irritant or severe irritant materials when one or more of the screens can provide convincing evidence. For suspected severe irritant materials, the proposed in vivo test permits the use of one rabbit and instillation of 0.01 ml (0.01 g) of the test material into the cornea. Materials that are not classified irritant or severe irritant by screens or severe irritant by one rabbit test are tested in two or three rabbits; 0.1 ml (0.1 g) is instilled into the conjunctival sac. The responses (corneal opacity, iritis and conjunctival redness) are scored according to the modified Draize scoring system at 24, 48 and 72 hr and 7 days post-instillation. A rabbit is considered positive when corneal opacity of 1 or above, iritis of 1 or above or conjunctival redness of 2 or above is present at 24, 48 or 72 hr post-instillation. The material is classified as a severe irritant when the rabbit in the one-animal test or two or more rabbits in the standard test have responses of corneal opacity of 3 or above and iritis of 2 at 24, 48 or 72 hr, or positive responses on day 7 after instillation. The material is classified as an eye irritant when two or more rabbits are positive but the responses are not severe and they clear 7 days after instillation. The material is classified as a non-irritant when no more than one rabbit is positive. The opinions expressed in this article are those of the authors and do not necessarily reflect the views of US Federal agencies.

Criteria for in vitro alternatives for the eye irritation test.

A proposal encompassing considerations and criteria for the development of in vitro alternatives to the eye irritation test has been developed and is presented here. Two factors need to be considered initially in developing an alternative test. The first is to determine whether the alternative assay is to be used as a screen or as a replacement for the eye irritation test. Less stringent acceptance criteria are required for an assay used as a screen than for that used as a replacement test. A screen is a preliminary test for the assessment of eye irritation. It is used for making preliminary decisions or establishing the direction for further testing. Screens answer fewer and less complex questions than a replacement test would, since the results from screens are usually confirmed by more definitive testing. A replacement test, however, must provide the same answers as in vivo methods for the assessment of eye irritation and must provide data for making a definitive toxicological assessment of eye irritation. The second factor to be considered is knowledge of the in vivo assay intended to be replaced. This knowledge should include the procedural aspects of the test and the regulatory information it provides. The following may be considered as criteria for in vitro tests used as screens or as replacements for the eye irritation test in rabbits: rationale (there should be a clear statement regarding the rationale for the use of a particular test in relation to the availability of other tests); relevance (the in vitro endpoint should have biological or physiological relevance to the effect to be detected in vivo); and validational (intralaboratory as well as interlaboratory validation must be conducted).

Use of ophthalmic topical anaesthetics.

Pretreatment of the eyes of rabbits with a topical anaesthetic can be viewed as a refinement of the test for eye irritation. It reduces pain at the time of test-material administration, decreases animal distress and permits easier application of the test agent to the eye. In some cases, however, use of an anaesthetic either alone or in combination with the test substance may alter ocular responses or provide little benefit. Although anaesthetic pretreatment may result in decreased pain at the time of test-compound administration, it does not affect possible pain after the effects of the anaesthetic have dissipated. Some anaesthetics are themselves irritating to eyes. In addition, anaesthetics reduce blinking and tearing, thereby maintaining the test-material concentration at the surface of the eye longer. Corneal permeability may also be increased with pretreatment use of an anaesthetic, and may bring the test agent into contact with more structures of the eye. Some anaesthetics delay healing after ocular injury. All of these varied effects may result in increased irritation to the eye. Overall, pretreatment with anaesthetics has usually resulted in a tendency for slightly higher irritation scores; eye irritancy classification is usually unaffected.

Screening procedures for eye irritation.

Screens aid in identifying some severe irritants or corrosives and eliminating them from consideration for in vivo eye irritation testing. Products may be evaluated for ocular irritation potential in a stepwise progression as follows: (1) products at pH extremes of 2 or below or of 11.5 or above may be considered to be ocular irritants; (2) based on chemical structure-activity considerations, some products may be judged to have ocular irritation potential; (3) validated and accepted in vitro systems may possibly be used as a screen in the future; (4) when a test material demonstrates severe acute dermal toxicity (lethality at < or = 200 mg/kg body weight), further testing for either dermal or ocular irritation may not need to be undertaken; (5) if a substance shows a primary dermal irritation index of 5 or above, it may be considered to be an ocular irritant; (6) materials that are not removed from consideration based on these proposed screens may then be considered for testing for ocular irritation in rabbits under accepted procedures. In a survey given to participants in the workshop, a high percentage believed that screens should be used. However, opinions on the use of the individual screens varied between the different interested groups attending, with the possible future use of in vitro screens for specific product lines having the highest percentage of agreement (57-100%).

The use of low-volume dosing in the eye irritation test.

The Draize rabbit eye test was developed to provide a method for assessing the irritation potential of materials that might come in contact with human eyes. The method involves the instillation of 0.1 ml of a test liquid (100 mg solid) into the conjunctival sac of an animal's eye. A refinement of the Draize test is the low-volume eye test in which 0.01 ml of a substance is placed directly on the cornea of the eye. Studies indicate that the low-volume method provides a better correlation to human eye irritation experience for some substances. The Interagency Regulatory Alternatives Group (IRAG) proposes that the low-volume eye test can be used to substantiate the irritancy of suspect severe ocular irritants that have not been eliminated by various pre-eye test 'screens'. A substance testing positive by the low-volume method can be classified as an irritant; one that tests negative will require further testing by the use of the 0.1-ml volume procedure. For all other definitive testing, the Draize test (0.1 ml) should be used. Results from a questionnaire distributed at the IRAG workshop showed that many workshop participants thought that the low-volume test should be used as an eye irritation screening procedure.

The use of blood in burn shock. Clinical and experimental study.

We have given whole blood as one of the main constituents of burn shock resuscitation for the past 28 years. To appraise the value of using whole blood, we have summarized the clinical experience of 2630 burn patients. Overall mortality was 4.18%. The lethal area of the burn were 50% of the population is expected to die was 82.8% total body surface area and 57.4% third-degree burns. The incidence of renal failure, pulmonary edema, and gastrointestinal bleeding was 0.9%, 0.4%, and 0.6% respectively. To confirm the advantage of transfusion of whole blood, we have carried out a series of experimental studies. Two groups of 25 dogs with 25% total body surface area full-thickness burns were treated with two resuscitation regimens. Group I was treated with whole blood, and group II with no blood, during the shock phase. After 48 hours, the infusions were stopped. Measurements were made before the burn and 2, 24, 48, 72, and 144 hours after the burn injury. The animals were then killed for histologic studies. From our data, we concluded that whole blood used in burn shock did not increase hemoconcentration or viscosity; it improved anemia, oncotic pressure, hypoproteinemia, acid-base balance, oxygenation, hemodynamics, and myocardial contractility, promoted cardionatrin secretion, reduced edema of tissue, and protected viscera from degenerative changes and bacterial colonization.

[Study on antifreeze protein in fishes. II. The cloning of antifreeze protein gene cDNA of Pseudopleuronectes yokohamae and its expression in E. coli].

Pseudopleuronectes yokohamae, existing in the Yellow Sea of China, contains antifreeze peptide (AFP). This protein could depress the serum freezing point. On the basis of purification and characterization of this protein, we synthesized a segment of Oligo-nucleotides of antifreeze protein gene as a primer and hybridized with the mRNA of Pseudopleuronectes yokohamae. The cDNA of antifreeze protein gene has specifically been reversely transcribed. This segment has been cloned onto pUC19 with Ecor I linker method. After confirmation of the insert segment of the cDNA of antifreeze protein gene, the zymogram was detected and the sequence of the nucleotides was determined. This recombinated clone was transformed into E. coli JM83 and expressed well.