[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.

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.

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.

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.

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.

Assessment of bone biopsy needles for sample size, specimen quality and ease of use.

OBJECTIVE: To assess whether there are significant differences in ease of use and quality of samples among several bone biopsy needles currently available. DESIGN: Eight commonly used, commercially available bone biopsy needles of different gauges were evaluated. Each needle was used to obtain five consecutive samples from a lamb lumbar pedicle. Subjective assessment of ease of needle use, ease of sample removal from the needle and sample quality, before and after fixation, was graded on a 5-point scale. The number of attempts necessary to reach a 1 cm depth was recorded. Each biopsy specimen was measured in the gross state and after fixation. RESULTS: The RADI Bonopty 15 g and Kendall Monoject J-type 11 g needles were rated the easiest to use, while the Parallax Core-Assure 11 g and the Bard Ostycut 16 g were rated the most difficult. Parallax Core-Assure and Kendall Monoject needles had the highest quality specimen in the gross state; Cook Elson/Ackerman 14 g and Bard Ostycut 16 g needles yielded the lowest. The MD Tech without Trap-Lok 11 g needle had the highest quality core after fixation, while the Bard Ostycut 16 g had the lowest. There was a significant difference in pre-fixation sample length between needles (P<0.0001), despite acquiring all cores to a standard 1 cm depth. Core length and width decrease in size by an average of 28% and 42% after fixation. CONCLUSION: Bone biopsy needles vary significantly in performance. Detailed knowledge of the strengths and weaknesses of different needles is important to make an appropriate selection for each individual's practice.

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.

Multiple organ dysfunction syndrome.

Multiple organ dysfunction syndrome, including acute respiratory distress syndrome (ARDS) and renal failure, is described, its clinical features outlined, its origins in tissue oxidative stress following severe infections, surgical trauma, ionizing radiation, high-dosage drugs and chemicals, severe hemorrhage, etc., are defined, and its prevention and treatment prescribed.

High-yield expression and purification of human interferon alpha-1 in Pichia pastoris.

For several years, interferon alpha-1, also known as interferon alpha-D, has been studied for treatment of various viral diseases, such as hepatic fibrosis caused by hepatitis B, herpes simplex virus keratitis, and bovine respiratory diseases in calves. Currently, recombinant human interferon alpha-D (rHuIFNalphaD) is expressed intracellularly in Escherichia coli or secreted by Bacillus subtilis and Saccharomyces cerevisiae. In this report, we describe the process of obtaining a relatively high-yield secretion of biologically active recombinant rHuIFNalphaD using the Pichia pastoris system. The process produced as high as 0.7 mg of purified protein per 20 ml of shake culture of rHuIFNalphaD with better bioactivity than the commercially available rHuIFNalphaD molecule produced in E. coli.

Extremely small sample size in some toxicity studies: an example from the rabbit eye irritation test.

The conventional sample-size equations based on either the precision of estimation or the power of testing a hypothesis may not be appropriate to determine sample size for a "diagnostic" testing problem, such as the eye irritant Draize test. When the animals' responses to chemical compounds are relatively uniform and extreme and the objective is to classify a compound as either irritant or nonirritant, the test using just two or three animals may be adequate.

Sclerotic bone metastases from sarcomatoid renal cell carcinoma.

We present a case of sarcomatoid renal cell carcinoma with multiple sclerotic skeletal metastatic lesions. Renal cell carcinoma is frequently metastatic at presentation, with a high incidence of skeletal involvement, classically described as osteolytic. However, sclerotic or osteoblastic metastatic skeletal lesions from renal cell carcinoma are rare, with only two previous reports identified in the literature, neither of which involved the sarcomatoid variant of renal cell carcinoma. In our case the sclerotic metastases were characterized by bone scan, computed tomography (CT), magnetic resonance imaging (MRI), and histologic analysis.

Characterization of a Rac1 signaling pathway to cyclin D(1) expression in airway smooth muscle cells.

We examined the importance of the Rho family GTPase Rac1 for cyclin D(1) promoter transcriptional activation in bovine tracheal myocytes. Overexpression of active Rac1 induced transcription from the cyclin D(1) promoter, whereas platelet-derived growth factor (PDGF)-induced transcription was inhibited by a dominant-negative allele of Rac1, suggesting that Rac1 functions as an upstream activator of cyclin D(1) in this system. Rac1 forms part of the NADPH oxidase complex that generates reactive oxygen species such as H(2)O(2). PDGF stimulated a substantial increase in intracellular reactive oxygen species, as measured by the fluorescence of dichlorofluorescein-loaded cells, and this was blocked by the glutathione peroxidase mimetic ebselen. Pretreatment with ebselen, catalase, and the flavoprotein inhibitor diphenylene iodonium each attenuated PDGF- and Rac1-mediated cyclin D(1) promoter activation, while having no effect on the induction of cyclin D(1) by mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase-1 (MEK1), the upstream activator of ERKs. Antioxidant treatment also inhibited PDGF-induced cyclin D(1) protein expression and DNA synthesis. Overexpression of an N-terminal fragment of p67(phox), a component of NADPH oxidase which interacts with Rac1, attenuated PDGF-induced cyclin D(1) promoter activity, whereas overexpression of the wild-type p67 did not. Finally, Rac1 was neither required nor sufficient for ERK activation. Taken together, these data suggest a model by which two distinct signaling pathways, the ERK and Rac1 pathways, positively regulate cyclin D(1) and smooth muscle growth.

Catalytic activation of extracellular signal-regulated kinases induces cyclin D1 expression in primary tracheal myocytes.

We have demonstrated that extracellular signal-regulated kinases (ERKs) and cyclin D1 are required for bovine tracheal myocyte DNA synthesis. We hypothesized that catalytic activation by ERKs may regulate cyclin D1 expression in these cells. To test this hypothesis, we examined the effects of two inhibitors of ERKs and two reagents that increase the level of activated ERKs on cyclin D1 protein abundance and promoter activity. ERK activity was inhibited either by PD98059, a synthetic inhibitor of mitogen-activated protein kinase (MAPK)/ERK kinase (MEK), the upstream signaling intermediate required and sufficient for ERK activation, or by transient transfection with a dominant-negative mutant of MEK1 (MEK-2A). The level of activated ERKs was increased by transient transfection with either a constitutively active form of MEK1 (MEK-2E) or wild-type ERK2 (MAPKwt). Cyclin D1 expression was assessed either by immunoblot or cotransfection with the full-length cyclin D1 promoter subcloned into a luciferase reporter. We found that pretreatment of bovine tracheal myocytes with PD98059 significantly attenuated platelet- derived growth factor (PDGF)-induced cyclin D1 protein abundance. Furthermore, transfection with MEK-2A reduced PDGF-induced cyclin D1 promoter activity. Finally, transfection with either MEK-2E or MAPKwt induced cyclin D1 promoter activity in the absence of growth factor treatment. We conclude that catalytic activation of ERKs regulates cyclin D1 expression in airway smooth-muscle cells.

Hydrogen peroxide activates extracellular signal-regulated kinase via protein kinase C, Raf-1, and MEK1.

We have previously demonstrated that hydrogen peroxide (H2O2) treatment of bovine tracheal myocytes increases the activity of extracellular signal-regulated kinases (ERK), serine/threonine kinases of the mitogen-activated protein (MAP) kinase superfamily thought to play a key role in the transduction of mitogenic signals to the cell nucleus. Moreover, H2O2-induced ERK activation was partially reduced by pretreatment with phorbol 12,13-dibutyrate, which depletes protein kinase C (PKC). In this study, we further examined the signaling intermediates responsible for ERK activation by H2O2 in airway smooth muscle, focusing on MAP kinase/ERK kinase (MEK), a dual-function kinase which is required and sufficient for ERK activation in bovine tracheal myocytes; Raf-1, a serine/threonine kinase known to activate MEK; and PKC. Pretreatment of cells with inhibitors of MEK (PD98059), Raf-1 (forskolin), and PKC (chelerythrine) each reduced H2O2-induced ERK activity. In addition, H2O2 treatment significantly increased both MEK1 and Raf-1 activity. No activation of MEK2 was detected. Together these data suggest that H2O2 may stimulate ERK via successive activation of PKC, Raf-1, and MEK1.

MEK1 is required for PDGF-induced ERK activation and DNA synthesis in tracheal myocytes.

We tested whether activation of mitogen-activated protein kinase/ extracellular signal-regulated kinase kinase-1 (MEK1) is required and sufficient for extracellular signal-regulated kinase (ERK) activation in airway smooth muscle cells. First, we transiently cotransfected bovine tracheal myocytes with an epitope-tagged ERK2 and a dominant-negative or a constitutively active form of the gene encoding MEK1 and assessed ERK2 activation by in vitro phosphorylation assay. Expression of the dominant-negative MEK1 inhibited platelet-derived growth factor (PDGF)-induced ERK2 activation, whereas expression of the constitutively active MEK1 induced ERK2 activation, suggesting that MEK1 is required and sufficient for ERK activation in these cells. Next, we assessed the effect of PD-98059, a synthetic MEK inhibitor, on PDGF-induced MEK1 and ERK activation. PD-98059 (10 microM) inhibited MEK1 and ERK activation, confirming that MEK1 is required for ERK activation in bovine tracheal myocytes. PD-98059 had no effect on Src or Raf-1 activity, evidence that PD-98059 is a specific inhibitor of MEK in this system. Finally, PD-98059 reduced PDGF-induced [(3)H]thymidine incorporation in a concentration-dependent manner, suggesting that catalytic activation of MEK1 and ERKs is required for DNA synthesis. We conclude that MEK1 is required for PDGF-induced ERK activation in bovine tracheal myocytes and that MEK1 and ERKs are required for PDGF-induced DNA synthesis in these cells.

Studies in surgical trauma: oxidative stress in ischaemia-reperfusion of rat liver.

1. Hypovolaemic shock associated with surgical trauma has been studied in a rat liver ischaemia-reperfusion model by determination of oxidative stress, lipid peroxidation and tissue infiltration of polymorphonuclear leucocytes. 2. Liver ischaemia alone resulted in slight liver oedema and polymorphonuclear leucocyte infiltration, a slight increase in thiobarbituric acid-reacting substances (an index of lipid peroxidation) and decreases in liver reduced glutathione and total radical-trapping antioxidant parameter, indices of oxidative stress. Ischaemia plus 30 min of reperfusion further increased liver oedema, polymorphonuclear leucocyte infiltration and thiobarbituric-acid reacting substances, and further decreased liver reduced glutathione and total radical-trapping antioxidant parameter. 3. After 60 and 90 min of reperfusion, oedema (40% increase), polymorphonuclear leucocyte infiltration (40-fold increase) and thiobarbituric-acid reacting substances (20-fold increase) were maximal, and liver reduced glutathione (75-95% decrease) and total radical-trapping antioxidant parameter (85-90% decrease) were at a minimum. 4. All parameters were exacerbated by 24 h starvation. Liver reduced glutathione closely paralleled total radical-trapping antioxidant parameter, and ischaemia alone depleted both by 30% in fed rats and 50% in fasted rats. 5. Oxidative stress and lipid peroxidation were associated more with the period of reperfusion and polymorphonuclear leucocyte infiltration. Polymorphonuclear leucocyte infiltration into lung also occurred after 90 min of liver reperfusion. 6. Possible mechanisms of hepatic ischaemia-reperfusion-induced oxidative stress are discussed.

Role of tissue glutathione in prevention of surgical trauma.

1. Surgical trauma has been associated with pre-anaesthesia fasting, anaesthetic toxicity, haemorrhage, hypovolaemic shock, and other pathological phenomena. Tissue glutathione (GSH), thiobarbituric acid-reacting substances (TBAR), and radical-trapping activity (RTA) have been determined at various time intervals after fasting, anaesthesia, and also after hepatic ischaemia and reperfusion as a model for haemorrhage and hypovolaemic shock. 2. Light ether anaesthesia of rats resulted in an immediate (5 min) and progressive decrease in liver and kidney total glutathione (GSH and GSSG), which was much greater in animals that had been fasted for 20 h. TBARs, a measure of lipid peroxidation, in rat liver and kidney increased as total GSH decreased. Fasting (20 h) alone decreased tissue GSH by 50%, and increased TBAR 100%; fasting plus 30 min of ether anaesthesia decreased tissue glutathione by 80 to 85%, and increased TBAR by some 600%. 3. Liver ischaemia alone decreased total liver GSH by 20% in the fed rat, and 50% in the fasted rat. Ischaemia, followed by reperfusion, decreased liver total GSH by 70% in the fed rat, and 90% in the fasted rat. The ratio of GSH/GSSG decreased from 16 in control animals to 7 in the fasted ischaemic rat, then to 1 in the fasted, ischaemic rat reperfused for 90 min. RTA of liver closely paralleled liver total GSH levels. TBAR was increased by ischaemia alone (50-100%), but more (400%) by 90 min reperfusion. 4. A complex series of molecular mechanisms including: (1) GSH depletion; (2) induction of CYP2E1 activity; (3) generation of reactive oxygen species; (4) lipid peroxidation; (5) cytokine release; and (6) leucocyte activation, are advanced to account for the toxic phenomena of surgical trauma and multiple system organ failure.

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.

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.