[Pathogenetic analysis of transfusion-related acute lung injury caused by human leukocytes antigen antibody against human leukocyte antigen]

From September 2019 to October 2020, pathogenetic analysis of three patients clinically diagnosed as transfusion-related acute lung injury (TRALI) caused by human leukocyte antibodies was conducted by Guangzhou Blood Centre, including 2 males and 1 female, aged 56, 50 and 20 years old, respectively. Solid phase agglutination, anti-human globulin test and flow cytometry method were used to detect the presence of antibodies against patients. Sequencing-based human leukocyte antigen (HLA-SBT) typing technique was used to detect the human leukocyte antigen (HLA) genotypes of patients. Lifecodes single antigen class Ⅰ/Ⅱ kit (LSA-Ⅰ/Ⅱ) were used to detect the specificity of HLA-class Ⅰ and class Ⅱ antibodies in donor blood by Luminex 200 liquid suspension chip system. The HLA specific antibodies and corresponding epitopes in donors were also analyzed. The results showed that　HLA class Ⅰ or class Ⅱ specific antibodies against TRALI patients were detected in the blood donors. The plasma of donor 3 received by patient 1 contained antibodies against the patient's HLA-DRB1*09∶01 antigen, and the epitopes mediating the antibody reaction of the donor and recipient were 70R, 31I, 70QA. There were antibodies against the HLA-A*11∶02, HLA-A*11∶01, DRB1*12∶02, and DRB1*09∶01 antigens of patient 2 in the plasma of donor 4, and the associated antigenic epitopes were 151AHA, 57V, and 16Y. Antibodies against the HLA-DRB1*14∶04, DRB1*11∶01, and DPB1*05∶01 antigens of patient 3 were present in the plasma of donor 6 and donor 7, and the associated epitopes were 96HK, 140TV, 13SE, and 111K.　Three cases of TRALI were confirmed to be caused by HLA antibodies through laboratory analysis, and human leukocyte antibody detection should be paid attention in clinically suspected cases of TRALI, and targeted diagnosis and treatment should be given.

Fermented soybean meal increases nutrient digestibility via the improvement of intestinal function, anti-oxidative capacity and immune function of weaned pigs

The nutritional components of fermented soybean meal (FSBM) vary because of the complex process of microbial fermentation. The objective of this study was to investigate the nutritional value of FSBM from two sources and explore the mode of actions of FSBM on the improvement of nutrient digestibility with the measurements of digestive enzymes and serum biomarkers. Eight weaned barrows (initial BW: 14.12 ± 0.24 kg) equipped with T-cannula in the distal ileum were allotted to a duplicated 4 × 4 Latin-square design with four experimental diets and four periods. Four experimental diets included a soybean meal control diet, two FSBM diets, and a nitrogen-free diet. The two sources of FSBM increased the contents of CP, amino acid and lactic acid, while decreased the levels of anti-nutritional factors, including glycinin, β-conglycinin and trypsin inhibitors. Compared to soybean meal control diet, both FSBM diets significantly increased the apparent and standardised ileal digestibility of CP and amino acids (P < 0.05), increased the activities of lipase, maltase and invertase in digesta (P < 0.05), increased total antioxidant capacity, activities of glutathione peroxidase and superoxide dismutase, the levels of interleukin-4, IgA, IgG and IgM in serum (P < 0.05), while decreased the levels of diamine oxidase, malondialdehyde, interleukin-6, and interleukin-2 in serum (P < 0.05). Additionally, the standardised ileal digestibility of amino acids were highly correlated with the aforementioned digestive enzymes and health-related serum biomarkers. In summary, FSBM diets showed an improved nutritional value evidenced by the higher nutrient digestibility, which may be partially derived from its beneficial effects on intestinal integrity, anti-oxidative capacity and immune function.

[The status and health risk assessment of dietary fipronil contamination among 20 provinces of China]

Objective: To understand the status and health risk assessment of dietary fipronil contamination among 20 provinces of China. Methods: A total of 13 kinds of dietary samples in Chinese total diet study include cereals, legumes, potatoes, meats, eggs, aquatics, dairies, vegetables, fruits, sugars, beverages and water, alcohols, condiments and their corresponding products. Among them, condiments were used in the preparation of 12 other sample categories; thus, the actual mixed dietary samples of each province covered 12 groups. A total of 240 mixed dietary samples were collected from 20 provinces in China from 2009 to 2013. After the sample extraction and cleanup, dietary samples were analyzed for the residues of fipronil and its metabolites to obtain the contamination levels of fipronil residues using liquid chromatography-high resolution mass spectrometry. The dietary intake of adult residents was estimated based on food consumption of general population of China. Results: Among the 240 dietary samples, the detection rate of fipronil was 10.4% (25 samples), and the detection rates of fipronil metabolites, i.e. fipronil desulfinyl, fipronil sulfone and fipronil sulfide were 20.4% (49 samples), 40.0% (96 samples) and 8.8% (21 samples), respectively. According to the dietary exposure analysis, the average lower and upper dietary exposure levels of fipronil residues in adult residents of China were 11.34 and 12.35 ng·kg(-1)·d(-1), accounting for 5.7% and 6.2% of acceptable daily intake (ADI), respectively. The highest adult dietary intake of fipronil residues was found in Hunan province, with a value of 72.98 ng·kg(-1)·d(-1), accounting for 36.5% of ADI. Vegetables were the main dietary source of fipronil residues, which contributed to 71.0% of the total intake dose. Conclusion: Fipronil residues were detected in varying degrees in dietary samples, yet the health risk caused by the dietary intake of adult residents among 20 provinces of China is low.

[Clinical analysis of 8 cases with anti-GQ1b antibody syndrome]

Objective: To investigate the clinical characterization, treatment and prognosis of anti-GQ1b antibody syndrome. Methods: The clinical data of 8 patients with positive serum anti-GQ1b antibody from the Department of Neurology of Nanjing Brain Hospital between June 2016 and July 2018 were analyzed retrospectively. Their serums were tested by immunoblotting. Relevant literatures were reviewed to investigate possible pathogenesis. Results: Of the 8 cases, 4 cases were male, 4 cases were female; their age ranged from 16 to 76 (47±21) years old. Seven of them were with acute onset, the time course of the disease ranged from 2 to 15 (7±4) days. Six cases had a history of influenza prior to the onset of the presenting symptoms. In terms of the clinical manifestations of the eight patients, two were affected with Guillain-Barre syndrome (GBS), two with Cavernous sinus syndrome, one with Miller Fisher syndrome, one with both GBS and spinal cord demyelination, one with Bulbar paralysis, and one with chronic inflammatory demyelinating polyneuropathy (CIDP). The anti-GQ1b antibody IgG in serum was positive in 6 patients, two of whom were combined with positive IgG of anti-GD1b antibody in serum. The anti-GQ1b antibody IgM in serum was positive in 1 patient, and the anti-GQ1b antibody IgM and anti-GT1b antibody IgM in cerebrospinal fluid (CSF) were both positive in the other patient. In terms of the treatment, 3 patients (3/8) received vitamin B treatment only, 2 patients (2/8) received steroid plus vitamin B treatment, 2 patients (2/8) received intravenous immunoglobulin (IVIG) plus vitamin B treatment, and 1 patient (1/8) received steroid plus IVIG treatment. During the 8-33 months' follow-up after discharge, 6 patients were significantly improved in their symptoms, one with mild diplopia, one with limbs weakness, numbness and difficulty in walking. The symptoms of one patient (case 3) fluctuated twice and recovered again after treatment. Conclusions: The disease spectrum of anti-GQ1b antibodies syndrome is broad, and main symptom is ophtalmoplegia. Immunotherapy with IVIG and steroid would be beneficial to prognosis.

[The effect of microRNA-21 on myocardial fibrosis in mice with chronic viral myocarditis]

Objective: To explore the effect of microRNA-21 (miR-21) on myocardial fibrosis in mice with chronic viral myocarditis (CVMC) and related mechanisms. Methods: Forty 4-week-old Balb/c male mice were randomly divided into 4 groups (n=10 each): phosphate buffer saline (PBS) group, CVMC group, CVMC+miR-21 inhibitor group, CVMC+isotype control group. The first injection of Coxsackie virus B3 (CVB3) or PBS was performed on day 0, and the total study time was 42 days. Each mouse in CVMC group, CVMC+miR-21 inhibitor group and CVMC+isotype control group was intraperitoneally (i.p) injected with 100TCID50 CVB3 0.1, 0.15, and 0.2 ml on day 0, 14, and 28, respectively. The mice in PBS group were i.p injected with the same dose of PBS at the same time point. After the initial infection, each mouse in CVMC+miR-21 inhibitor group and CVMC+isotype control group was intravenously injected with 0.1 ml miR-21 inhibitor or 0.1 ml isotype control, on day 14 and 28. Cardiac function was measured on surviving mice of 4 groups by echocardiography on day 42. Then, the hearts were removed aseptically to observe the expressions of green fluorescence protein (GFP). The myocardial pathological changes were examined with HE, Masson staining and the myocardial pathological scores (PS), the collagen volume fraction (CVF) were calculated respectively. The levels of miR-21, collagen typeⅠ-A1 (COL1-A1) and collagen type Ⅲ-A1 (COL3-A1) mRNA in heart were detected by quantitative real-time polymerase chain reaction (RT-qPCR). Furthermore, the expressions of transforming growth factor-β1 (TGF-β1) and mothers against decapentaplegic homolog 7(Smad7) in heart were determined with Western blot assay. Results: (1) Cardiac function in 4 groups: Compared with PBS group, left ventricular end systolic diameter (LVESD) and left ventricular end diastolic diameter (LVEDD) were markedly increased in CVMC group and CVMC+isotype control group (all P<0.05), whereas the left ventricular ejection fraction (LVEF) was decreased (P<0.05). LVESD and LVEDD were significantly decreased, and LVEF was increased in CVMC+miR-21 inhibitor group compared with those in CVMC group and CVMC+isotype control group (all P<0.05). (2) Myocardial pathological changes: The expressions of GFP in CVMC+miR-21 inhibitor group and CVMC+isotype control group were visible in heart tissues frozen sections. The hearts in CVMC group and CVMC+isotype control group were enlarged and stiff, inflammatory cells were visible and significantly increased myocardial fibrosis was evidenced in mice of these two groups. Higher PS and CVF were evidenced in CVMC group (PS: 1.14±0.69 vs. 0, CVF: (17.86±2.61)% vs. (5.70±1.42)%, all P<0.05) and CVMC+isotype control group(PS: 1.00±0.63 vs. 0, CVF: (16.78±2.58)% vs. (5.70±1.42)%, all P<0.05) compared to PBS group. Compared with CVMC group and CVMC+isotype control group, degree of cardiac fibrosis was reduced in mice of CVMC+miR-21 inhibitor group (CVF: (11.01±2.55)% vs. (17.86±2.61)%, (11.01±2.55)% vs. (16.78±2.58)%, all P<0.05), whereas PS were similar between them (PS: 0.89±0.60 vs. 1.14±0.69, 0.89±0.60 vs. 1.00±0.63, all P>0.05). (3) Cardiac expressions of miR-21, COL1-A1 and COL3-A1 mRNA: The cardiac expressions of miR-21, COL1-A1 mRNA, COL3-A1mRNA in CVMC group and CVMC+isotype control group were markedly higher than those in PBS group (all P<0.05), which were significantly downregulated in CVMC+miR-21 inhibitor group (all P<0.05 vs. CVMC group and CVMC+isotype control group). (4) The cardiac expressions of TGF-β1 and Smad7 protein: The cardiac expressions of TGF-β1 protein in CVMC group and CVMC+isotype control group were markedly higher, whereas the cardiac Smad7 protein expressions were significantly lower (all P<0.05) than those in PBS group (all P<0.05), these changes could be reversed in CVMC+miR-21 inhibitor group (P<0.05 vs. CVMC group and CVMC+isotype control group). Conclusions: Our results suggest that miR-21 contributes to the myocardial fibrosis in CVMC mice through modulating TGF-β1/Smad7 signaling pathway.

Gastric infusion of short-chain fatty acids can improve intestinal barrier function in weaned piglets

Background

The present study was conducted to investigate the effects of gastric infusion of short-chain fatty acids (SCFA) on gut barrier function in a pig model. In this study, 21 DLY barrows with an average initial body weight of (8.31 ± 0.72) kg were randomly allotted into three treatments: (1) control, (2) infusing low SCFA, S1, (3) infusing high SCFA, S2. The experimental period lasted for 7 days.

Results

Gastric infusion of SCFA increased the concentrations of SCFA in serum and digesta, and enhanced the mRNA and protein abundances of SCFA receptors in pig intestine (P < 0.05). Moreover, gastric infusion of SCFA led to alteration of intestinal morphology, elevation of intestinal development-related gene abundances, and decrease of apoptotic cell percentage, as well as reduction of pro-apoptosis gene and protein abundances (P < 0.05). Besides, the jejunal SLC₇A₁ and ileal DMT1 mRNA abundances in the SCFA infusion groups were higher than those in the control group (P < 0.05). Additionally, gastric infusion of SCFA increased the mRNA abundances of Occludin and Claudin-1 in the duodenum and ileum, enhanced Lactobacillus spp counts in the ileal digesta, decreased the mRNA and protein abundances of IL-1β in the colon, and reduced Escherichia coli count in the ileal digesta (P < 0.05).

Conclusions

These data indicated that gastric infusion of SCFA, especially high SCFA concentration, may be beneficial to gut development of piglets via improving gut morphology, decreasing apoptotic cell percentage, and maintaining intestinal barrier function.

Electronic supplementary material

The online version of this article (10.1186/s12263-019-0626-x) contains supplementary material, which is available to authorized users.

[Clinical and pathological characteristics and outcome of 46 children with autoimmune hepatitis]

Objective: To review and analyze the clinical and pathological data of children with autoimmune hepatitis (AIH). Methods: Medical records of 46 patients hospitalized in Pediatric Liver Diseases Treatment and Research Center, Fifth Medical Center, General Hospital of People's Liberation Army(PLA) from April 2012 to April 2018 were extracted. Medical data included type of AIH, clinical manifestations, biochemical parameters, liver biopsy results, and outcomes of treatment were analyzed retrospectively. Among 46 children, 19 were males and 27 were females. The age of onset was 10.1(1.4-18.0) years old. Chi-Square test, Rank sum test or t test were used for inter-group comparison. Results: There were 32 (70%)AIH-I cases and 14 (30%)AIH-Ⅱ cases (χ(2)=12.565, P=0.000). Among the 46 patients, there were 5 modes of onest: 17 cases (37%) had acute viral hepatitis-like presentation, 2 cases (4%) had fulminant hepatic failure, 9 cases (20%) had insidious onset, 5 cases (11%) showed cirrhosis and portal hypertension, and 13 cases (28%) were incidentally found to be due to elevated hepatic aminotransferases. Comorbidities including primary sclerotic cholangitis (n=3), primary biliary cholangitis (n=1), systemic lupus erythematosus (n=1) and inflammatory bowel disease (n=2), were all seen in AIH-Ⅰ cases. The elevated biochemical parameters of these patients were as follows: alanine aminotransferase (n=46), aspartate transminase (n=46), total bilirubin (n=35) γ-glutamyl transpeptadase (n=39), γ-globulin (n=32) and IgG (n=33). The γ-globulin and IgG levels were significantly higher in AIH-Ⅰ patients than those with AIH-Ⅱ((32±9)% vs. (23±8)%, t=3.217, P=0.002,(27±10) vs. (18±8)g/L, t=3.193, P=0.003, respectively). Thirty-nine patients received liver biopsy, among whom 22 (56%) with inflammation grade (G)≥3, 26(67%) with fibrosis stage (S) ≥3, and 7 with hepatic cirrhosis (S4) according to pathological analysis. Typical histopathological changes of AIH included: 36 cases of interfacial hepatitis (92%), 23 cases of lymphocyte/plasma cell infiltration (59%), 3 cases of rosette (8%). Forty patients received prednisolone monotherapy or combined with azathioprine after diagnosis. Complete remission was seen in 29 (72%) patients, partial remission in 10 (25%) patients and no response in 1 (3%) patient. Among complete remission patients, 15 (52%) had relapse in the process of prednisolone reduction. Repeated liver biopsy performed in 8 patients after treatment showed that hepatic inflammation and fibrosis were both improved in 6 patients, only inflammation was alleviated without fibrosis improvement in 1 patient, and neither inflammation nor fibrosis was improved in 1 case. The length of follow-up was 3.3 (0.3-10.5) years, and none of the 39 prednisolone-responded cases discontinued treatment successfully. Adverse effect of long-term prednisolone therapy included bilateral cataract (n=6), spinal fracture accompanied with delayed bone age development (n=1). Conclusions: AIH-Ⅰ is more common than AIH-Ⅱ in children, with diverse clinical characteristics. Most cases have progressive liver inflammation and fibrosis when diagnosed. Prednisolone monotherapy or combined with azathioprine could achieve both biochemical and pathological improvement, but relapse is inevitable during drug tapering, hence long-term treatment is essential.

[Cephalic artery peak velocity variation during passive leg raising can predict fluid responsiveness in mechanically ventilated severe sepsis patients with spontaneous breathing]

Objective: To explore whether cephalic artery peak velocity variation during passive leg raising (ΔVpeak(CA)-PLR) could effectively predict fluid responsiveness in mechanically ventilated severe sepsis patients with spontaneous breathing. Methods: Total of 38 patients on mechanical ventilation with spontaneous breathing admitted to the Fourth Departments of Intensive Care Unit (ICU) of Fujian Provincial Hospital from January to December in 2017 were enrolled.The patients were diagnosed with severe sepsis or sepsis shock.The peak velocity in cephalic artery (Vpeak(CA)) during PLR was measured by bedside portable ultrasonic, and then ΔVpeak(CA)-PLR was calculated.All patients received volume expansion (VE) test and the changes of stroke volume during VE test (ΔSV-VE) were measured.Patients were classified as responsive group or non-responsive group according to the ΔSV-VE increased ≥15% or not after VE test.Furthermore, the sensitivity and specificity of ΔVpeak(CA)-PLR for predicting fluid responsiveness were evaluated by receiver operating characteristic (ROC) curve.The comparisons between groups were performed with Student's unpaired two-tailed t test, and Pearson's test was used for the correlation analysis. Results: Among the patients, 22 cases responded to VE test and the rest 16 cases did not.There were no significantly differences in age, gender, body mass index, infection site, sepsis-related organ failure assessment score, acute physiology and chronic health evaluation Ⅱ score, ventilator parameters and dose of vasoactive agent between the two groups.The ΔVpeak(CA)-PLR in responsive group was markedly higher than that in non-responsive group (15.7%±4.2% vs 6.9%±4.3%, t=6.240, P<0.05), and the ΔVpeak(CA)-PLR in the responsive group was positively related to the ΔSV-VE (r=0.723, P<0.05). Furthermore, the area of ΔVpeak(CA)-PLR under ROC curve was 0.912.The sensitivity and specificity of ΔVpeak(CA)-PLR≥12.2% to predict fluid responsiveness in the patients with sepsis were 81.8% and 87.5%, respectively. Conclusion: ΔVpeak(CA)-PLR measured by bedside portable ultrasonic can predict the fluid responsiveness in mechanically ventilated severe sepsis patients with spontaneous breathing, and it can be used to guide further fluid resuscitation.

Effects of maize naturally contaminated with aflatoxin B1 on growth performance, intestinal morphology, and digestive physiology in ducks

This study was conducted to determine the effects of maize naturally contaminated with aflatoxin B1 (AFB1) on growth performance, intestinal morphology, relative digestive organs weight, digestive enzymes activities, and biochemical index of intestinal development in ducks. A total of 640 ducks was blocked on the basis of sex and body weight, and then allocated randomly to 2 treatments with 20 pens per treatment and 16 ducks per pen. The experiment lasted for 5 wk, and dietary treatments included basal diet (CON) and diets with 100% of normal maize replaced by AFB1 contaminated maize. Detectable levels of other toxins were present but only AFB1 exceeded limits and the level of AFB1 was 195.4 ug/kg in the contaminated maize, and ranged from 2.91 to 120.02 ug/kg in the starter diet and 2.03 to 153.12 ug/kg in the grower diet. Feeding AFB1 contaminated diets decreased (P < 0.05) ADG and ADFI during the whole experiment, whereas F/G during d 15 to 35 and d zero to 35 was reduced (P < 0.05). The mortality of ducks fed AFB1 contaminated diets increased (P < 0.05). Ducks fed AFB1 contaminated diets had greater (P < 0.05) relative weights of proventriculus and gizzard on d 14 as well as the duodenum, jejunum, and ileum on d 14 and 35. Feeding AFB1 contaminated diets increased (P < 0.05) crypt depth, villus width, and surface area in the duodenum on d 35 and villus height, villus width, and surface area in the jejunum on d 14. The activities of alkaline phosphatase and leucine aminopeptidase in the jejunum brush border together with chymotrypsin and trypsin in the pancreas increased (P < 0.05) on d 14 with the inclusion of AFB1 contaminated maize. The jejunum villus became long and wide in ducks fed AFB1 contaminated diets. Taken together, the feeding of maize naturally contaminated with AFB1 caused adverse effects on growth performance and intestinal morphology, and altered digestive physiology and development.

Excess of dietary montmorillonite impairs growth performance, liver function, and antioxidant capacity in starter pigs

Montmorillonite (MMT) is widely used as a mycotoxin adsorbent in animal feeds, but its safety remains unclear. This study was conducted to investigate the safety of MMT supplementation in diets fed to starter pigs. A total of 120 32-d-old piglets (initial weight, 8.0 ± 0.9 kg) were randomly allotted into dietary treatments with graded MMT levels (0 [FS 0], 0.5% [FS 0.5], 1.0% [FS 1.0], 2.5% [FS 2.5], and 5.0% [FS 5.0]) with 6 replicate pens per treatment and 4 pigs per pen. All diets were fed for 28 d. As the MMT level increased, ADG and G:F changed in a linear and quadratic manner, while ADFI was linearly decreased ( > 0.05). Compared with FS 0, ADG, ADFI, and G:F of pigs in FS 1.0 increased ( < 0.05). However, the ADFI in pigs of FS 5.0 was lower than that in pigs of FS 0 ( < 0.05). The relative liver weight activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) changed in a linear and quadratic manner ( < 0.05). Compared with FS 0, pigs in FS 2.5 and FS 5.0 had a greater serum ALT ( < 0.05), while AST activity significantly increased in pigs of FS 5.0 ( < 0.05). Dietary MMT supplementation decreased serum Mg content in a linear and quadratic manner ( < 0.05), while Zn and Cu contents were linearly decreased ( < 0.05). Serum Zn and Cu contents of pigs in FS 0.5, FS 2.5, and FS 5.0 groups were lower than those in the control. Pigs fed with 2.5% and 5% MMT showed hepatic histopathological changes, including swelling, granular and vesicular degeneration, and apparent vacuolar degeneration. In addition, the content of serum total antioxidant capacity (T-AOC) and activity of glutathione peroxidase (GSH-PX) decreased in a linear and quadratic manner ( < 0.05). Compared to the control, 5.0% MMT significantly increased piglets' serum malondialdehyde (MDA) concentration and decreased GSH-PX activity ( < 0.05). T-AOC concentration in the pigs fed 2.5% and 5.0% MMT was lower than that in the control group ( < 0.05). Serum superoxide dismutase (SOD) activity changed in a quadratic manner ( < 0.05). Piglets in FS 1.0 showed a higher SOD activity when compared with the control ( < 0.05). These results indicate that supplementation of MMT higher than 1.0% can negatively affect liver structure and serum mineral content, and 5.0% MMT supplementation would also decrease feed intake, aggravate liver damage, and reduce the antioxidant capacity of starter pigs. Therefore, excess supplementation of MMT is not safe in starter pigs.

The addition of protein-bound amino acids in low-protein diets improves the metabolic and immunological characteristics in fifteen- to thirty-five-kg pigs

This study was to evaluate the effects of supplementation of AA form (crystalline vs. protein bound) in low-protein diets on growth, metabolic, and immunological characteristics of pigs. A total of 80 barrows (PIC 327 × 1050; 15.57 ± 0.13 kg BW and 48 ± 2 d of age), housed in 4 pigs per pen with 5 pens per treatment, were assigned to 4 dietary treatments of 17, 15, and 13% CP and 13% CP plus casein for 28 d. The crystalline AA were supplemented to meet the requirement of indispensable AA in pigs. Results showed that pigs fed the 13% CP diet or the 13% CP plus casein diet had lower ( < 0.01) ADG and ADFI and a greater ( < 0.01) feed:gain ratio than pigs fed the 17% CP or 15% CP diets over the 4-wk study period. Compared with other diets, pigs fed the 13% CP diet had decreased concentrations of plasma urea nitrogen, albumin ( < 0.01), and mRNA expressions of Toll-like receptor 4 (), nuclear factor kappa B (; < 0.05), and Toll-interacting protein (; < 0.01) in the ileum and also increased activity of plasma glutamate-pyruvate transaminase ( < 0.05) and concentrations of IL-1β ( < 0.05) and tumor necrosis factor-α ( < 0.01); however, these characteristics were partly normalized by feeding the 13% CP plus casein diet. Furthermore, the plasma concentration of insulin-like growth factor 1 (IGF-1; < 0.01) and mRNA expressions of protein kinase B (), mammalian target of rapamycin (), and ribosomal protein S6 kinase () in longissimus muscle were increased ( < 0.05) in pigs fed the 13% CP plus casein diet relative to pigs fed the 17% CP or 15% CP diets. In summary, reducing dietary CP level from 17% to 15% had no effect on growth, metabolic, and immunological characteristics of 15- to 35-kg pigs. A further reduction of dietary CP level up to 13% would lead to poor growth performance, but metabolic and immunological characteristics were partly normalized using protein-bound AA to replace synthesized AA in the 13% CP diet.

[A retrospective study on the liver pathological characteristics and the effect of antiviral treatment for 1 to 7 years old children with heptitis B e antigen negative chronic hepatitis B]

OBJECTIVE

To investigate the liver pathological characteristics and the clearance rate of hepatitis B surface antigen (HBsAg) with antiviral treatment for 1 to 7 years old children with heptitis B e antigen(HBeAg)-negative chronic hepatitis B.

METHOD

A total of 49 cases with HBeAg-negative chronic hepatitis B were treated with interferon (IFN) or IFN treatment for 6 months added with lamivudine, and were followed up for at least 6 months.Retrospective analysis was performed on the liver pathological characteristics, the efficacy of antivirus treatment and its influencing factors of the HBsAg clearance rate in the cases from June 2006 to December 2013 in the 302 Hospital of People's Liberation Army.The χ(2) test was used to compare the rates.

RESULT

(1)The median age of cases was 3 years old(1-7 years old), 38 children were male(78%). Cases in the age group 1-2, >2 -3, >3 -4, >4-5, >5-6 and >6-7 were 7, 8, 14, 6, 6 and 8 respectively. HBsAg was 100% positive in mother of the cases. (2)There were 7 children whose pre-treatment alanine aminotransferase (ALT) were ≤80 U/L and pre-treatment ALT>200 U/L in 25 children. There were 24 children whose pre-treatment HBVDNA ≥1×10(7) U/ml. Genetype analysis was detected in 43 children, 3 children were B genotype, 38 were C genotype, 2 were B and C genotype. (3)Liver biopsy was performed in all children. The degree of liver inflammation ≥2 was seen in 48 (98%) children.Severe liver fibrosis and cirrhosis were found in 21(43%) children. (4)In the age group 1-2, >2-3, >3-4, >4-5, >5-6 and >6-7 years old , the clearance of HBsAg was 5, 6, 2, 1, 0 and 0 respectively. The HBsAg clearance rate between 1-3 years old group and 3-7 years old group has significant difference ((73%(11/15) vs. 9%(3/34), χ(2)=18.180, P=0.000). (5)The clearance of HBsAg in male group was 11, but 3 in female group.It showed no significant difference between two groups (χ(2)=0.073, P=0.787). (6) The clearance rate of HBsAg were 0, 24%(4/17) and 40%(10/25) in the groups of pre-treatment ALT ≤80 U/L, 80<ALT≤200 U/L and ALT >200 U/L, respectively. There were no significant difference between the groups of ALT≤200 U/L and ALT > 200 U/L(χ(2)=2.223, P=0.136). In the groups with pre-treatment HBV DNA <1×10(7)U/ml and HBV DNA≥1×10(7)U/ml, the clearance rate of HBsAg was 28%(7/25) and 29%(7/24). There were no significant elifference between two groups(χ(2)=0.008, P=0.928). (7)The clearance rate of HBsAg was 33%(7/21) in children with severe liver fibrosis and cirrhosis, while 25%(7/28) in children who had no severe liver fibrosis and cirrhosis.There were no significant difference between two groups(χ(2)=0.408, P=0.523).

CONCLUSION

There are obvious liver injuries and severe liver fibrosis in 1-7 years old children with HBeAg-negative chronic hepatitis B. The HBsAg clearance rate in the children with antiviral treatment correlated with age, among those who received antiviral treatment before 3 years old, the HBsAg clearance rate is relatively higher.

Involvement of PKA signalling in anti-inflammatory effects of chitosan oligosaccharides in IPEC-J2 porcine epithelial cells

Weaning is characterized by intestinal inflammation, which is a big challenge in pig industry. Control of intestinal inflammation is important for improvement of growth performance and health. Therefore, the study was focused on the anti-inflammatory activity of low-molecular-weight chitosan oligosaccharide (LCOS) in a porcine small intestinal epithelial cell line (IPEC-J2). The results showed that TNF-α, as inflammation inducer, significantly upregulated the mRNA expression of IL-8 and MCP-1. Afterwards, LCOS significantly attenuated mRNA expression of IL-8 and MCP-1 induced by TNF-α in the cells. Mannose (MAN), as ligand of mannose receptor, had no effect on the anti-inflammatory activity of LCOS, which suggested that mannose receptor may not involve in the anti-inflammatory activity of LCOS in IPEC-J2 cells. Interestingly, N-[2-(p-bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide 2HCl hydrate (H89), as PKA (protein kinase A)-specific inhibitor, reversed the mRNA expression of IL-8 when co-cultured with LCOS. Furthermore, LCOS concentration dependent downregulated the mRNA expression of claudin-1 compared with TNF-α treatment. However, the trans-epithelial electric resistance (TEER) was not affected by LCOS when co-cultured with TNF-α in 3 hr. In conclusion, LCOS have a potent anti-inflammatory activity, and as a feed additives, may be useful for the inhibition of inflammatory process in weaning period of pigs with intestinal inflammation occurring.

Benzoic acid beneficially affects growth performance of weaned pigs which was associated with changes in gut bacterial populations, morphology indices and growth factor gene expression

This study was conducted to investigate the effects of benzoic acid (BA) on growth performance, intestinal development and intestinal barrier function in weaned pigs. Ninety weaned pigs were randomly assigned to one of three treatments: a basal diet (CON), the basal diet supplemented with 2000 mg/kg benzoic acid (BA1) and 5000 mg/kg benzoic acid (BA2). At the end of days 14 and 42, six pigs per treatment were randomly selected to collect plasma and intestinal samples. Results showed that BA supplementation not only improved final body weight, daily growth and feed conversion ratio from days 15 to 42 and days 1 to 42, but also decreased the activity of plasma diamine oxidase (day 42) and the pH values of jejunal contents (day 14) (p < 0.05). Ileal Bacillus populations (day 14) were increased by BA, while Escherichia coli counts in the ileum and caecum (day 42) were decreased (p < 0.05). Higher Lactobacillus counts occurred in the ileum (day 14, 42) of BA1-fed piglets as compared to CON and BA2-fed piglets (p < 0.05). In addition, BA supplementation increased the ratio of villus height to crypt depth (day 14, 42) and decreased the crypt depth (day 14) (p < 0.05). Growth-stimulating factors (insulin-like growth factor-1, day 42; insulin-like growth factor-1 receptor, day 14, 42) and tight junction protein (occludin, day 14, 42; zonula occludens-1, day 42)-related gene mRNA levels were upregulated in the jejunum of piglets fed BA diets (p < 0.05). In conclusion, this study provides the first evidence that BA has beneficial effects on intestinal development and intestinal barrier function of weaned pigs, which can partly explain why growth performance of pigs was improved by dietary BA supplementation.

Effects of corn type and fasting time before slaughter on growth and plasma index in weaning pigs

A 2 × 2 factorial experiment was conducted to evaluate the effects of dietary corn type (waxy corn [WC] vs. nonwaxy corn [NC]) and fasting period (2 h vs. 12-16 h) before slaughter on growth and plasma index in weaning pigs. Twenty-four crossbred barrows (8.26 ± 0.47 kg) were allotted to 4 treatments with 6 replications of 1 pig per replicate metabolism cage. Waxy corn contained less fat, a lower amylase:amylopectin ratio, more CP, and more starch than NC. Pigs fed the WC diet had lower jejunum digesta pH compared with those fed the NC diet ( < 0.05). Maltase activity in the jejunum and ileum mucosa ( < 0.01), sucrose activity in the ileum mucosa ( < 0.01), and amylase activity in the pancreas and jejunum digesta ( < 0.05) were increased in pigs fed the WC diet relative to those fed the NC diet. But the total tract apparent digestibility (TTAD) of starch and CP was lower for the WC group ( < 0.05). Ingestion of the NC diet resulted in higher ( < 0.05) ADG and ADFI in the second week but did not affect ADG ( = 0.091) and the feed:gain ratio (F:G; = 0.077) during the whole experiment period. The plasma glucose ( < 0.01) concentration was higher and high-density lipoprotein cholesterol (HDL-C; < 0.01) concentrations was lower in the hepatic portal vein in pigs fed the WC diet relative to those fed the NC diet. Fasting 2 h before slaughter decreased the jejunum and ileum digesta pH compared with the 12-h fasting group ( < 0.01). Villus height increased in the duodenum ( < 0.01) and jejunum ( < 0.05) and the villus height:crypt depth ratio increased in the duodenum ( < 0.05) of pigs after shortening the fasting period before slaughter. Shortening the fasting time before slaughter resulted in higher plasma glucose ( < 0.05) concentrations and a higher HDL-C:low-density lipoprotein cholesterol (LDL-C) ratio ( < 0.05) whereas the LDL-C ( < 0.05) concentrations were reduced in the hepatic portal vein. The results of this experiment indicate that although the production performance of both WC and NC diets is equal, the glucose concentration is higher and HDL-C is lower in the portal vein for the WC diet, and fasting time before slaughter has an influence on the plasma index and intestinal morphology in weaning pigs.

Discovery of GSK2795039, a Novel Small Molecule NADPH Oxidase 2 Inhibitor

AIMS

The NADPH oxidase (NOX) family of enzymes catalyzes the formation of reactive oxygen species (ROS). NOX enzymes not only have a key role in a variety of physiological processes but also contribute to oxidative stress in certain disease states. To date, while numerous small molecule inhibitors have been reported (in particular for NOX2), none have demonstrated inhibitory activity in vivo. As such, there is a need for the identification of improved NOX inhibitors to enable further evaluation of the biological functions of NOX enzymes in vivo as well as the therapeutic potential of NOX inhibition. In this study, both the in vitro and in vivo pharmacological profiles of GSK2795039, a novel NOX2 inhibitor, were characterized in comparison with other published NOX inhibitors.

RESULTS

GSK2795039 inhibited both the formation of ROS and the utilization of the enzyme substrates, NADPH and oxygen, in a variety of semirecombinant cell-free and cell-based NOX2 assays. It inhibited NOX2 in an NADPH competitive manner and was selective over other NOX isoforms, xanthine oxidase, and endothelial nitric oxide synthase enzymes. Following systemic administration in mice, GSK2795039 abolished the production of ROS by activated NOX2 enzyme in a paw inflammation model. Furthermore, GSK2795039 showed activity in a murine model of acute pancreatitis, reducing the levels of serum amylase triggered by systemic injection of cerulein.

INNOVATION AND CONCLUSIONS

GSK2795039 is a novel NOX2 inhibitor that is the first small molecule to demonstrate inhibition of the NOX2 enzyme in vivo.

Rheumatoid arthritis patients with hip fracture: a nationwide study

SUMMARY

The study was to investigate the outcomes of rheumatoid arthritis (RA) patients with hip fractures with a large-scale, population-based, nationwide, case-cohort study using the Taiwan National Health Insurance database. The group has hip fractures at a younger age, higher complication, and mortality rate, which indicate that early intervention is necessary.

INTRODUCTION

This study seeks to evaluate the incidence, mortality, and complication rates in RA patients with hip fractures, using a nationwide database.

METHODS

Data were collected from the National Health Insurance Research Database of Taiwan. The study group included 117,129 patients with hip fractures diagnosed from January 2004 to December 2010. Matching based on the propensity of RA patients was used. In total, 1,088 hip fractures were reported among patients with RA. Patients with hip fractures were divided into two groups: those without RA (controls) and those with RA (RA group). The incidence of hip fracture and mortality and complication rates after the hip fracture were then compared between the two groups.

RESULTS

RA patients had a significantly higher incidence of hip fracture (3,260/100,000 person-years) compared with the general population (72/100,000 person-years). Hip fractures occurred significantly earlier among RA patients (70.6±5.3 years) compared with the control group (76.1±6.2 years). Cumulative mortality rates at 6-month and 1-year follow-up were significantly higher among patients in the RA group (9.47 and 18.47%) compared to the controls (8.47 and 13.62%) and among RA patients without hip fractures (3.24 and 6.16%). There was a significantly higher incidence of osteomyelitis after hip fracture among the RA group than among the body mass index-, comorbidity-, age-, and sex-matched patients in the control group.

CONCLUSIONS

Compared to patients without RA, those with RA have a higher incidence of hip fractures at a relatively younger age and with higher complication and mortality rates. Steroid and disease-modifying anti-rheumatic drugs, the most common medicine in Taiwanese RA patients, might contribute to the high incidence of fracture and post-op infection. Appropriate early intervention to prevent hip fractures in RA patients is a critical issue in rheumatology care.

Nationwide cohort study of hip fractures: time trends in the incidence rates and projections up to 2035

SUMMARY

A growing elderly population is expected worldwide, and the burden of hip fractures on health care system will continue to increase. By 2035, there will be a 2.7-fold increase in the number of hip fractures in Taiwan. The study provides quantitative basis for the future distribution of medical resources.

INTRODUCTION

Hip fractures have long been recognized as a major public health concern. The study aimed to determine time trends in the incidence of hip fractures and to forecast the number of hip fractures expected in Taiwan up to 2035.

METHODS

A nationwide survey was conducted using data from the Taiwan National Health Insurance Research Database from 2004 to 2011. A total of 141,397 hip fractures were identified, with a mean of 17,675 fractures/year. Annual incidences of hip fractures were calculated and tested for trends. Projections of the incidence rates of hip fractures and bed days associated with hip fractures were calculated using Poisson regression on the historical incidence rates in combination with population projections from 2012 to 2035.

RESULTS

The incidence rates of hip fracture during 2004-2011 were 317 and 211 per 100,000 person-years among women and men, respectively. Over this 8-year period, the age-standardized incidence of hip fracture decreased by 13.4% among women and 12.2% among men. Despite the decline in the age-standardized incidence, the absolute number of hip fractures increased owing to the aging population. The number of hip fractures is expected to increase from 18,338 in 2010 to 50,421 in 2035-a 2.7-fold increase. The number of bed days for 2010 and 2035 was estimated at 161,248 and 501,995, respectively, representing a 3.1-fold increase.

CONCLUSIONS

The socioeconomic impact of hip fractures will be high in the near future. This study provides a quantitative basis for future policy decisions to serve this need.

Identification of a series of 1,3,4-oxadiazol-2-amines as potent alpha-7 agonists with efficacy in the novel object recognition model of cognition

A series of α7 nicotinic acetylcholine receptor full-agonists with a 1,3,4-oxadiazol-2-amine core has been discovered. Systematic exploration of the structure-activity relationships for both α7 potency and selectivity with respect to interaction with the hERG channel are described. Further profiling led to the identification of compound 22, a potent full agonist showing efficacy in the novel object recognition model of cognition enhancement.

The concentration of antibiotic in fresh-frozen bone graft

We investigated the antibiotic concentration in fresh-frozen femoral head allografts harvested from two groups of living donors. Ten samples were collected from patients with osteoarthritis of the hip and ten from those with a fracture of the neck of the femur scheduled for primary arthroplasty. Cefazolin (1 g) was administered as a pre-operative prophylactic antibiotic. After storage at -80 degrees C for two weeks the pattern of release of cefazolin from morsellised femoral heads was evaluated by an in vitro broth elution assay using high-performance liquid chromatography. The bioactivity of the bone was further determined with an agar disc diffusion and standardised tube dilution bioassay. The results indicated that the fresh-frozen femoral heads contained cefazolin. The morsellised bone released cefazolin for up to four days. The concentration of cefazolin was significantly higher in the heads from patients with osteoarthritis of the hip than in those with a fracture.Also, in bioassays the bone showed inhibitory effects against bacteria.We concluded that allografts of morsellised bone from the femoral head harvested from patients undergoing arthroplasty of the hip contained cefazolin, which had been administered pre-operatively and they exhibited inhibitory effects against bacteria in vitro.

Public health workforce enumeration: beware the "quick fix"

The most common source of information on workforce in the United States is the Bureau of Labor Statistics (BLS), a branch of the Department of Labor. In 1998, 14 public health workforce titles were added to the BLS Standard Occupational Classification (SOC) system. While this was a constructive step, it is not a "quick fix," because these additional titles do not solve the longstanding problems inherent in capturing accurate PH workforce data. As is true for all currently available sources, BLS statistics capture a limited segment of public health's broadly defined and multidisciplinary workforce. A standard system of data collection is needed to guide planning to sustain the present and future workforce. Revision of the 1998 SOC in preparation for the 2010 Census is now underway. This presents an opportunity for the public health community to act on prior recommendations regarding workforce data and advocate for more inclusive enumeration of public health occupations that can inform policies and planning for the current and future workforce.

The determination of in vitro pingyangmycin hydrochloride plasma protein binding by microdialysis

Microdialysis sampling was used to study the binding of pingyangmycin hydrochloride (PYM) to plasma proteins in canis familiaris blood. In vitro plasma protein binding fractions were evaluated in a series of PYM concentration. The results showed decreased protein binding with increased concentration. The data was analyzed using the Scatchard analysis and Klotz plot. The results showed that the Scatchard plot and Klotz plot were linear with good correlation coefficient, indicating a good agreement of the experimental data to the theoretical equation.

Synthesis, properties and microemulsion formulation of ibuprofen eugenol ester

Ibuprofen-eugenol ester (IEE), a highly lipophilic compound, was synthesized from ibuprofen in order to reduce the common side effects induced by this classic anti-inflammatory drug. IEE was isolated as an amorphous whitish solid with a melting point at 40.2 +/- 0.1 degrees C, whose structure was confirmed by IR, 1H NMR and MS spectra. The hydrolysis results showed that the ester was stable over a wide pH range from 1.1-9.96. However, it could be hydrolyzed easily by enzymes from rat plasma and rat liver homogenate. A pharmaceutically acceptable microemulsion system was presented and characterized in terms of stability, droplet size distribution (DSD) and their solubilization capacity for IEE. The solubility of IEE in the optimized microemulsion formulation was about 21,000 times higher than that in water. The AUC of ibuprofen from the prodrug showed a remarkable increase compared to oral ibuprofen suspension. These results suggest that synthesizing the ibuprofen prodrug was justified and the presented microemulsion system might be a promising oral dosage form for poorly water-soluble drugs.

Stereoselective synthesis of (Z)-enethiols and their derivatives: vinylic S(N)2 reaction of (E)-alkenyl(phenyl)-lambda3-iodanes with thioamides

[reaction: see text]. Exposure of (E)-beta-alkylvinyl(phenyl)-lambda3-iodanes to thioamides in dichloromethane at room temperature was found to result in a bimolecular nucleophilic substitution (S(N)2) at the vinylic carbon atom to give inverted (Z)-enethiols and/or (Z)-S-vinylthioimidonium salts. Vinylic S(N)2 reactions with thioureas are also discussed.

{3,3′-[2,2′-(Ethylenedioxy)dibenzylidene]bis(S-methyl dithiocarbazate)}nickel(II)

The tetradentate N(2)S(2) Schiff base ligand 3,3'-[2,2'-(ethylenedioxy)dibenzylidene]bis(S-methyl dithiocarbazate) (H(2)L), prepared by the condensation of S-methyl dithiocarbazate with 1,4-bis(2-formylphenyl)-1,4-dioxabutane in a 1:2 molar ratio, reacts with nickel acetate to form the title neutral metal complex, [Ni(C(20)H(20)N(4)O(2)S(4))]. The X-ray structure of the complex shows a distorted square-planar geometry around the Ni atom. The monomeric units are weakly associated into dimers via a long Ni.S interaction [3.569 (1) A]. These dimeric units are then linked by C-H.S intermolecular contacts to form a polymeric chain along the a axis.

Preparation of stilbene-tethered nonnatural nucleosides for use with blue-fluorescent antibodies

The synthesis of the first examples of stilbene-tethered hydrophobic C-nucleosides is described. Compounds of this type are targeted for use with our recently reported "blue-fluorescent antibodies" with the aim of probing native and nonnatural DNA. The nucleophilic addition of aryl Grignard reagents to either a protected 2'-deoxy-1'-chloro-ribofuranose or a protected 2'-deoxy-ribonolactone was the key synthetic step and afforded C-nucleosides in good yields. Both routes resulted in a final product that was >/=90% of the beta-anomer. Amide- and ether-based linkers for attachment of trans-stilbene to the nucleobase were assessed for utility during synthesis and in binding of the ligands to a blue-fluorescent monoclonal antibody. X-ray structures of each complex were obtained and serve as a guideline for second-generation stilbene-tethered C-nucleosides. The development of these hydrophobic nucleosides will be useful in current native and nonnatural DNA studies and invaluable for investigations regarding novel, nonnatural genomes in the future.

[Study on the preparation of baicalin complex with phospholipid]

OBJECTIVE

To choose the optimization conditions for the formation of baicalin complex with phospholipid.

METHOD

A reasonable criterion of accurate evaluation was established, by which such factors as temperature, the ratio of baicalin to phospholipid and the concentration of reactants were examined and the orthographic design was used.

RESULT

The best conditions were obtained through statistical analysis and proof test.

CONCLUSION

The formation of baicalin complex with phospholipid was greatly influenced by the solvent, concentration and reactant ratio.

Continuous-wave 4.3-mum intracavity difference frequency generation in an optical parametric oscillator

We have achieved 150 mW of cw output at 4.3mum, using difference frequency mixing in a singly resonant optical parametric oscillator (OPO). We pumped the OPO cavity, which contains periodically poled LiNbO(3) (PPLN), with a 14-W 1.06-mum Nd:YAG laser to generate a signal at 1.7 mum and an idler at 2.8 mum. Mixing of the two waves at the same crystal temperature and grating spacing yielded emission in the mid IR. This technique avoids the mid-IR absorption-high-threshold problem, which has limited the cw performance of PPLN OPO's at wavelengths beyond 4 mum. Provided that tunability is not required, this method is a simple alternative to multiple-crystal configurations.

Prevention for the 21st century: setting the context through undergraduate medical education

The generation of medical students now being taught will be practicing into the middle of the next century. They will be expected to provide an expanding array of clinical preventive services and be responsible for the health and well-being of entire populations and communities. Although prevention principles are being taught in many contexts, most medical schools do not have adequate curriculum-tracking systems that allow them to track the delivery of education and training in disease prevention and health promotion. The Bureau of Health Professions of the Health Resources and Services Administration (HRSA) and the Association of Teachers of Preventive Medicine have worked on several projects that have culminated in the development of a set of core competencies in preventive medicine for undergraduate medical education. In 1997 they convened a task force of medical educators from a broad array of basic science and clinical disciplines representing major U.S. medical teaching societies. The task force reviewed and updated the 1984 Inventory of Knowledge and Skills Relating to Disease Prevention and Health Promotion so that it would be relevant to faculty in diverse specialty areas and could be integrated throughout the medical curriculum. They then created a list of competencies that are essential from the perspective of each discipline and all disciplines. The article gives the context for teaching preventive medicine, presents the core competencies, and serves as the introduction to a supplement to Academic Medicine on teaching preventive medicine throughout the undergraduate medical curriculum.

Core competencies for preventive medicine residents: Version 2.0

During the early 1990s, the American College of Preventive Medicine (ACPM), with support from the Health Resources and Services Administration (HRSA), identified core competencies and performance indicators (measures to assess their achievement) for all preventive medicine residents. After the competencies were approved, distributed by the ACPM and HRSA, and published in the American Journal of Preventive Medicine, they were integrated in various ways into the operation of individual residency programs. Changes in the health care system during the decade, however, necessitated an update of the original competencies to better equip preventive medicine educators to prepare residents for new roles those in preventive medicine can play in a restructured health care system. HRSA funded an effort to produce Version 2.0 of the preventive medicine competencies based on review and refinement of the original competencies through a consensus process. This article includes these revised core competencies and performance indicators.

Diode-pumped 1-W continuous-wave Er:YAG 3-mum laser

We have demonstrated 1.15 W of Gaussianlike (M(2) = 2) cw output at 2.94 mum from a diode laser end-pumped monolithic laser crystal composed of Er-doped yttrium aluminum garnet (YAG) bonded to undoped YAG. The laser was pumped with two polarization-coupled 2.5-W flared laser diodes that provided a 45-mum pump waist with a low N.A. (<0.04) . Output at 2.94 mum was generated with a 34% slope efficiency and a greater-than-unity quantum efficiency.

History of federal legislation in health professions educational assistance in dental public health, 1956-97

Health professions education assistance in dental public health has been congressionally authorized in one form or another during the last four decades. The US Department of Health and Human Services (and its predecessor, the Department of Health, Education, and Welfare) has been a focal point for managing these federal programs. This report tracks the history of relevant national legislation, beginning in the 1950s with the Health Amendment Acts of 1956 and continuing most recently with the Health Professions Education Extension Amendments of 1992. The number of dental public health professionals trained and available to provide expertise and leadership to improve community oral health status has been tied to the presence and intensity of federal programming in this area.

Filling the gap: equity and access to oral health services for minorities and the underserved

BACKGROUND AND OBJECTIVES

Family physicians and other primary care providers play a pivotal role in preventing oral disease, especially among minority and underserved populations who have limited access to dental services and poorer oral health status. Oral diseases/conditions, such as caries, baby bottle tooth decay, gingivitis, periodontitis, oral pharyngeal malignancies, and orofacial trauma, are prevalent and costly, yet largely preventable. Given their role in promoting and protecting overall health and their historical role in serving minority and underserved families, family physicians occupy a unique position to assure equity, access, and improvement in oral health for all Americans.

Population-based medical education: linkages between schools of medicine and public health agencies

PURPOSE

To examine the educational linkages between medical schools and public health agencies (PHAs); characterize programs for medical student placement at PHAs; explore attitudes toward using PHAs as student teaching sites; and investigate factors that facilitate or hinder such placements.

METHOD

A 20-item questionnaire was mailed in the summer of 1994 to all 134 allopathic medical schools in the United States (for schools with more than one campus, each campus was counted as a separate school). The chi-square and Mann-Whitney U tests were used to assess associations between variables.

RESULTS

A total of 108 schools (81%) responded. Of these, 68 (63%) reported having a program that places some or all students at PHAs. The most common facilitating factors were proximity of PHA(s) (84%), faculty interest in public health (76%), support of the PHA director and personnel (67%), and faculty appointments for public health personnel (63%). Two barriers differentiated schools having a PHA placement program from those not having one: lack of faculty interest (p = .001) and lack of a designated PHA contact person (p = .002).

CONCLUSION

An unexpectedly large number of schools placed students in PHAs to receive training. However, medical schools are not utilizing the full potential of PHAs as teaching sites.

Performance indicators for assessing competencies of preventive medicine residents

Heightened national interest in population-based medicine, clinical preventive services, and health care management underscores the current need for definition and assessment of physician competency in these areas. This article describes a project sponsored by the Health Resources and Services Administration (HRSA) to develop competencies for each of the three specialty areas in preventive medicine and appropriate measures for the achievement of those competencies. We discuss fundamental issues surrounding assessment that helped guide the process, types of measurement strategies, and criteria for effective competencies and performance indicators. The article also explains the Work Group process used to reach consensus and identifies concerns and challenges raised during this process. We include the list of specialty competencies and performance indicators developed by the project. The project, entitled "Improving Training of Preventive Medicine Residents through the Development and Evaluation of Competencies," served as a model for interorganizational collaboration between the federal government (HRSA); a specialty society, the American College of Preventive Medicine (ACPM); and a preventive medicine residency program, State University of New York (SUNY) at Stony Brook. The commonality of competencies expected of residents in all three specialty areas of preventive medicine--occupational medicine, general preventive medicine and public health, and aerospace medicine--reaffirmed the rationale for including all of these areas within the single specialty of preventive medicine.

Substituted phthalocyanine-sensitized photochemical generation of superoxide anion radical

The quantum yield of phthalocyanine-photosensitized generation of superoxide anion radical (O2-) was measured by the electron spin resonance (ESR) technique. From the redox potential data, it is concluded that O2- is formed by electron transfer from the singlet excited state (not triplet or ground state) of phthalocyanines (PCs) to oxygen. Since a much larger theoretical quantum yield of O2- generation (phi c) than experimental (phi m) was found, it is suggested that charge recombination processes between O2- and PCs+ occur more rapidly than O2- trapping by 5,5-dimethyl-1-pyrroline-1-oxide (DMPO). The results indicate that the use of DMPO as a spin trap is not an ideal method for measurement of the quantity of O2- formed via photosensitization.

Alexandrite laser frequency doubling in beta-BaB(2)O(4) crystals

Efficient and tunable coherent ultraviolet (360-390 nm) generation in beta-BaB(2)O(4) crystals using type-I phase matching at room temperature is presented. The phase-matching angle is characterized with an alexandrite laser with a wavelength tuning range of 725-785 nm. The crystal angular bandwidth of 0.9 mrad-cm and spectralbandwidth of 1.15 nm-cm are also measured. UV output pulse energy of 105 mJ at 378 nm with 31% energy conversion efficiency is achieved.

Infant mortality increase despite high access to tertiary care: an evolving relationship among infant mortality, health care, and socioeconomic change

In this study, the determinants of an apparent increase in the infant mortality rate of an urban population with high access to tertiary neonatal care are reviewed. For a 4-year period (1980 to 1983), all infant deaths (n = 422) of the 32,329 births to residents of the City of Boston were analyzed through linked vital statistics data and a review of medical records. A significant increase in the infant mortality rate occurred in 1982 due to increases in three components of the infant mortality rate: the birth rate of very low birth weight infants (less than 1,500 g), the neonatal mortality rate of normal birth weight infants (greater than or equal to 2,500 g), and the mortality rate of infants dying during the postneonatal period (28 to 365 days). These increases were associated with inadequate levels of prenatal care. Although transient, the impact of the observed alterations in these infant mortality rate components was enhanced by a more long-standing phenomenon: the stabilization of mortality rates for low birth weight infants. This stabilization allowed the increases in other component rates to be expressed more fully than in previous years. In this report a mechanism is shown whereby fully regionalized neonatal care ultimately may confer to the infant mortality rate a heightened sensitivity to socioeconomic conditions and levels of adequate prenatal care.

Laser beam combiner: applications to space-borne laser communications

An attractive source for spaceborne laser communications is the directly modulated single-mode GaAs/GaAlAs injection laser. GaAlAs lasers, however, show low power per diode and wide beam divergence. A simple optical concept for a laser beam combiner overcomes diode laser limitations: an array of closely packed parallel collimated laser beams can be handled in an optical system as a single beam. Diffractive spreading causes all bundle beams to overlap in the far field, producing incoherent power addition with 50% power throughput and good far-field performance.

Determining tunable diode laser spectrometer performance through measurement of N(2)0 line intensities and widths at 7.8 microm

The N(2)O R(8) doublet of the 11(1)0-01(1)0 band at 7.8 microm was measured by a tunable diode laser spectrometer designed and assembled at Perkin-Elmer. The spectra were digitized and least-squares fitted to Voigt line profiles to yield N(2)O line parameters and a quantitative measure of instrument performance. Scans at various pressures produced consistent spectral line values: S(0) = (0.1746 +/- 0.0043)cm(-2)/atm at 300 K, alpha(L)(N(2)O - N(2)O) = (0.1066 +/- 0.0041)cm(-1)/atm,alpha(D) = (1.194 +/- 0.018) x 10(-3) cm(-1), andalpha(L)(N(2)O - N(2)) = (0.0870 +/- 0.0015)cm(-1)atm. A spectrum with several levels of synthetic noise added was used to verify the fitting algorithm's stability. The spectrometer was shown to possess an excellent SNR (e.g., 900:1) and wave number precision (</=2 X 10(-4 cm-1)) for spectral scans with 0.1-sec time constant.