The musculoskeletal consequences of breast reconstruction using the latissimus dorsi muscle for women following mastectomy for breast cancer: A critical review.

Breast reconstruction using the latissimus dorsi (LD) flap following mastectomy is an important management option in breast cancer. However, one common, but often ignored, complication following LD flap is shoulder dysfunction. The aim of this critical review was to comprehensively assess the musculoskeletal impact of LD breast reconstruction and evaluate the functional outcome following surgery. Five electronic databases were searched including; Medline, Embase, CINAHL Plus (Cumulative Index to Nursing and Allied Health), PubMed and Web of Science. Databases were searched from 2006 to 2016, and only full text, English language articles were included. Twenty-two observational studies and two surveys were reviewed with sample sizes ranging from six to 206 participants. The majority of studies had small sample sizes and were retrospective in nature. Nevertheless, there is evidence to suggest that there is some degree of weakness and reduced mobility at the shoulder following LD muscle transfer. The literature demonstrates that there is considerable morbidity in the immediate post-operative period with functional recovery varying between studies. The majority of work tends to be limited and often gives conflicting results; therefore, further investigation is required in order to determine underlying factors that contribute to a reduction in function and activities of daily living.

Characteristics of persons who inject drugs and who witness opioid overdoses in Vietnam: a cross-sectional analysis to inform future overdose prevention programs.

BACKGROUND: Persons who use opioids have a high risk of overdose and associated mortality. In Vietnam, little is known about the characteristics of this population and the persons who are witness to those overdoses. One approach to combatting fatal overdose has been the use of peer interventions in which a friend or injecting partner administers overdose reversal medication, but availability in Vietnam of these medications is limited to pilot programs with aims to expand in the future (Le Minh and V.F. Go, Personal Communication, 2016). The primary objective of this paper is to explore the characteristics associated with witnessing three or more overdoses in a lifetime. METHODS: This cross-sectional analysis used baseline data from a four-arm randomized control trial conducted in Thai Nguyen, Vietnam, known as the Prevention for Positives project. One thousand six hundred seventy-three PWID were included in the analysis. We conducted bivariable and multivariable logistic regression to identify characteristics associated with witnessing three or more overdoses in a lifetime. Characteristics explored included education, employment, marital status, risky drug use behaviors, locations for accessing syringes, recent overdose, history of incarceration, drug treatment, and having slept outside in the past 3 months. RESULTS: Seventy-two percent (n = 1203) of participants had witnessed at least one overdose in their lifetime, and 46% had witnessed three or more overdoses (n = 765). In the multivariable model, having less than secondary education (AOR 0.70; 95% CI 0.57, 0.86), having slept outside in the past 3 months (AOR 1.77; 95% CI 1.31, 2.40), having a history of incarceration (AOR 1.33; 95% CI 1.07, 1.65), having a history of drug treatment (AOR 1.41; 95% CI 1.12, 1.77), experiencing a recent non-fatal overdose (AOR 3.84; 95% CI 2.36, 6.25), injecting drugs daily (AOR 1.79; 95% CI 1.45, 2.20), receptive needle sharing (AOR 1.30; 95% CI 1.04, 1.63), and number of years injecting (AOR 1.04; 95% CI 1.02, 1.07) were significantly associated with witnessing three or more overdoses. CONCLUSIONS: Targeted interventions are needed to train persons witnessing an overdose to administer overdose-reversal medication. This includes targeting persons prior to release from prisons, drug treatment centers, and those accessing syringe exchange programs. Additional research should assess the burden of witnessing an overdose as well as locations for medication distribution. Assessments of the training capacity and needs for implementing these programs among drug using peers in Vietnam are of the utmost importance.

Radiofrequency of suprascapular nerve as an analgesic strategy for chronic pain management. Systematic review and meta-analysis.

INTRODUCTION: Chronic shoulder pain is highly prevalent in the general population. Many different analgesic strategies have been described, including radiofrequency treatment to the suprascapular nerve (RFS); however, the effectiveness this approach remains unclear, and no strong recommendation can be made. The aim of this systematic review is to analyse the latest clinical trials evaluating the effectiveness of RFS techniques applied to the suprascapular nerve in terms of management of chronic shoulder pain, post-procedural functionality, and adverse effects. METHODS: We performed a systematic review of clinical trials retrieved from Medline, Embase and the CENTRAL databases. We included trials comparing RFS with other strategies, including placebo, that had as their primary outcome measures pain rated on a visual analogue scale, functionality rated on a shoulder pain and disability index (SPADI), and the incidence of adverse events. Risk of bias was analysed using the Cochrane RoB2 tool. Evidence was analysed using a random effects model and heterogeneity was quantified using the I2 test. RESULTS: We identified 3030 trials, of which 8 met the inclusion criteria (n = 408). Seven had a high risk of bias. Pain intensity at 1 and 3 months was lower in patients receiving RFS, with a standardised mean difference (SMD) of -0.9 (95% CI [-1.1, 0.33], p = 0.29; I2 88%, p < 0.001) and -1.17 (95% CI [-2.49, 0.14], p = 0.08; I2 97%, p < 0.001), respectively. Functional compromise at 1 and 3 months decreased in patients receiving RFS, with an SMD of -0.31 (95% CI [-0.91, 0.29], p = 0.31; I2 80%, p < 0.001) and -1.54 (95% CI [-3.26, 0.19], p = 0.08; I2 98%, p < 0.001), respectively. No RFS-related adverse events were described. CONCLUSION: The evidence suggests that RFS reduces pain and improves functionality. However, the certainty of the evidence is low.

Transitioning into the workforce during the COVID-19 pandemic: Understanding the experiences of student diagnostic radiographers.

INTRODUCTION: The COVID-19 pandemic, with associated pressures on healthcare services and workforce, had implications for final year Diagnostic Radiography students completing their training and transitioning into employment. The aim of this study was to explore their experience as novice practitioners starting work and integrating into the workforce during a time of national crisis. METHODS: Five early career Diagnostic Radiographers, eligible to join the temporary HCPC register, were recruited. One to one interviews were completed online exploring their thoughts, feelings and experiences. Participants had the option of using photographs to aid communication. RESULTS: Interviews were transcribed, emerging themes identified and coded. Four main themes emerged specifically related to the COVID-19 pandemic, (i) perceived challenges associated with joining the workforce, (ii) managing expectations and unexpected outcomes during transition, (iii) adapting to changes in systems and structures, (iv) sense of uncertainty relating to professional identity. The impacts were experienced beyond the work environment into social and personal lives. Participants demonstrated resilience as they adapted to their shifting lives and drew on the support of clinical colleagues and University academics for help. They did report feelings of concern and anxiety. The participants all expressed a sense of feeling valued and supported in their new roles. CONCLUSION: The Pandemic was unprecedented and created uncertainty in terms of workforce requirements. This study highlights the personal impact and professional responses of novice practitioners, who felt a sense of duty and care to help support the NHS and others. IMPLICATIONS FOR PRACTICE: This will help in the understanding of the transition of student into employment and what wider support needs to be in place prior, during and after this phase.

"I refused to drink but they still forced me": A mixed-methods approach to understanding the pathways to reduce alcohol use among Vietnamese people with HIV.

AIMS: This study explores the effects of two evidence-based alcohol reduction counseling interventions on readiness to change, alcohol abstinence self-efficacy, social support, and alcohol abstinence stigma among people with HIV (PWH) who have hazardous alcohol use in Vietnam. METHODS: PWH receiving antiretroviral therapy (ART) were screened for hazardous drinking and randomized to one of three study arms: combined intervention (CoI), brief intervention (BI), and standard of care (SOC). A quantitative survey was conducted at baseline (N = 440) and 3-month post-intervention (N = 405), while in-depth interviews were conducted with a subset of BI and CoI participants at baseline (N = 14) and 3 months (N = 14). Data was collected from March 2016 to August 2017. A concurrent mixed-methods model was used to triangulate quantitative and qualitative data to cross-validate findings. RESULTS: At 3 months, receiving the BI and CoI arms was associated with 2.64 and 3.50 points higher in mean readiness to change scores, respectively, compared to the SOC group (BI: ß = 2.64, 95% CI: 1.17-4.12; CoI: ß = 3.50, 95% CI 2.02-4.98). Mean alcohol abstinence self-efficacy scores were 4.03 and 3.93 points higher among the BI and CoI arm at 3 months, compared to SOC (BI: ß = 4.03, 95% CI: 0.17-7.89; CoI: ß = 3.93, 95% CI: 0.05-7.81). The impacts of the interventions on social support and alcohol abstinence stigma were not significant. Perceived challenges to refusing drinks at social events remained due to strong alcohol abstinence stigma and perceived negative support from family and friends who encouraged participants to drink posed additional barriers to reducing alcohol use. CONCLUSIONS: Both the CoI and BI were effective in improving readiness to change and alcohol abstinence self-efficacy among PWH. Yet, participants still faced significant barriers to reducing their drinking due to social influences and pressure to drink. Interventions at different levels addressing social support and alcohol abstinence stigma are warranted.

Modeling vitamin B1 transfer to consumers in the aquatic food web.

Vitamin B1 is an essential exogenous micronutrient for animals. Mass death and reproductive failure in top aquatic consumers caused by vitamin B1 deficiency is an emerging conservation issue in Northern hemisphere aquatic ecosystems. We present for the first time a model that identifies conditions responsible for the constrained flow of vitamin B1 from unicellular organisms to planktivorous fishes. The flow of vitamin B1 through the food web is constrained under anthropogenic pressures of increased nutrient input and, driven by climatic change, increased light attenuation by dissolved substances transported to marine coastal systems. Fishing pressure on piscivorous fish, through increased abundance of planktivorous fish that overexploit mesozooplankton, may further constrain vitamin B1 flow from producers to consumers. We also found that key ecological contributors to the constrained flow of vitamin B1 are a low mesozooplankton biomass, picoalgae prevailing among primary producers and low fluctuations of population numbers of planktonic organisms.

An open study of interferon in HIV-antibody-positive men.

Alpha-2a-recombinant interferon (Roferon A) was given subcutaneously in a dose of 3 mega units twice weekly for 15-18 months to 14 HIV-antibody-positive, p24-antigen-negative men with minimal HIV-related disease. Interferon was well-tolerated and safe. Although there was either improvement or lack of deterioration initially in 22 out of 26 HIV disease markers, including lymphadenopathy, thrombocytopenic purpura and nail fungal infection, there were 11 instances of HIV disease indicators appearing during the study. At 15 months, six patients were withdrawn from the study because of clinical and immunological deterioration.

Inhibition of membrane-bound lytic transglycosylase B by NAG-thiazoline.

The lytic transglycosylases cleave the bacterial cell wall heteropolymer peptidoglycan with the same specificity as the muramidases (lysozymes), between the N-acetylmuramic acid and N-acetylglucosamine residues, with the concomitant formation of a 1,6-anhydromuramoyl residue. The putative catalytic residue in the family 3 lytic transglycosylase from Pseudomonas aeruginosa, Glu162 as identified by sequence alignment to the homologous enzyme from Escherichia coli, was replaced with both Ala and Asp by site-directed mutagenesis. Neither mutant enzyme differed structurally from the wild-type enzyme, as judged by CD spectroscopy, but both were enzymatically inactive confirming the essential role of Glu162 in the mechanism of action of this lytic transglycosylase. The beta-hexosaminidase inhibitor NAG-thiazoline was shown to inhibit the activity of lytic transglycosylase activity, thus providing the first direct evidence that the formation of the 1,6-anhydromuramoyl residue may proceed through an oxazolinium ion intermediate involving anchimeric assistance. Using surface plasmon resonance and difference absorbance spectroscopy, Kd values of 1.8 and 1.4 mM, respectively, were determined for NAG thiazoline, while its parent compound N-acetylglucosamine neither inhibited nor appeared to bind the lytic transglycosylase with any significant affinity.

Viscosity of food gums determined in vitro related to their hypoglycemic actions.

Experiments were carried out in vitro and in normal human subjects to evaluate alternative food-grade viscous polysaccharides as agents for reducing postprandial hyperglycemia and to assess the relationship between the in vitro and in vivo performance of the polysaccharides. A 1:1 mixture of xanthan and locust bean gum (X/LBG) had the greatest viscosity at equivalent concentrations and shear rates and was more effective than guar gum, xanthan, or locust-bean gum at inhibiting glucose movement in vitro. It was not, however, more efficient in lowering postprandial blood glucose and plasma insulin in human subjects when incorporated in a drink containing 50 g glucose. When the different gums were acidified and reneutralized to mimic conditions in the gut, there was a better correlation between viscosity and blood glucose and plasma insulin levels. This effect may explain why X/LBG was no more effective than the other gums in reducing postprandial hyperglycemia in man.

Rapid determination of bacterial abundance, biovolume, morphology, and growth by neural network-based image analysis

Annual bacterial plankton dynamics at several depths and locations in the Baltic Sea were studied by image analysis. Individual bacteria were classified by using an artificial neural network which also effectively identified nonbacterial objects. Cell counts and frequencies of dividing cells were determined, and the data obtained agreed well with visual observations and previously published values. Cell volumes were measured accurately by comparison with bead standards. The survey included 690 images from a total of 138 samples. Each image contained approximately 200 bacteria. The images were analyzed automatically at a rate of 100 images per h. Bacterial abundance exhibited coherent patterns with time and depth, and there were distinct subsurface peaks in the summer months. Four distinct morphological classes were resolved by the image analyzer, and the dynamics of each could be visualized. The bacterial growth rates estimated from frequencies of dividing cells were different from the bacterial growth rates estimated by the thymidine incorporation method. With minor modifications, the image analysis technique described here can be used to analyze other planktonic classes.

Motile chemosensory behaviour of phagotrophic protists: mechanisms for and efficiency in congregating at food patches.

Phagotrophic protists are capable of congregating at point sources of food within a few minutes, from distances of up to several cm in the case of ciliates, or several mm in the case of microflagellates. This is exemplified by four ciliate species and a heterotrophic flagellate. Congregation is accomplished by the combined effect of more than one type of chemosensory motile behaviour including "kinetic responses", "temporal-gradient sensing", and "helical klinotaxis". The results are discussed in terms of microscale patchiness in nature.

Modelling of microscale patch encounter by chemotactic protozoa.

A model of protozoan chemotaxis, based on the rate of change of chemoreceptor occupancy, was used to analyse the efficiency of chemotaxis in a variety of situations. Simulated swimming behaviour replicated patterns observed experimentally. These were classified into three forms of chemosensory behaviour; run-tumble, steered turning, and helical klinotaxis. All three could be simulated from a basic model of chemotaxis by modifying memory times and rotational velocities. In order to steer during helical klinotaxis, the cell must have a short term memory for responding to a signal within a fraction of the time period of the helix. Steered turning was identified as a form where cells react to negative changes in concentration by steering around the turn to swim back up the gradient. All 3 forms were quite effective for encountering targets within the response radius. A response to negative changes in concentration, experienced when the cell is moving away from a target, was found to be important in the absence of periodic changes in swimming direction. The frequency of patch encounter at a fixed density was calculated to be roughly proportional to swimming speed. On the basis of the model, cells are only able to sense point sources within a radius of a few mm. However, even a response radius of 1 mm is enough to increase encounter probability of otherwise minute targets by 2 orders of magnitude. The mean time for patch encounter was calculated to be an exponential function of the mean distance between patches. This results in a very sharp threshold at approximately 6 cm, above which they are not encountered by protozoa within time periods of several days.

Preparation and use of monoclonal antibodies for identifying Crimean-Congo hemorrhagic fever virus.

Seven monoclonal antibodies were prepared against a South African strain of Crimean-Congo hemorrhagic fever (CCHF) virus and were found to be directed against viral nucleocapsid protein. Five of the monoclonal antibodies reacted to high titer in indirect immunofluorescence (IF) tests and enzyme-linked immunosorbent assays (ELISA) with 22 strains of CCHF virus and failed to cross-react with the closest antigenic relative of CCHF, Hazara virus, or with 4 other nairoviruses which need to be distinguished from CCHF virus in Africa. These antibodies, used in the IF technique, readily detected antigens induced by all strains of CCHF virus included in the study in cell culture monolayers and mouse brain tissue, which represent the systems commonly used for isolation of CCHF virus. The IF technique with monoclonal antibodies constitutes a rapid and specific means of identifying newly isolated strains of CCHF virus.

A population-based seroprevalence study in South Africa as a tool in the polio eradication initiative.

A seroprevalence study for poliomyelitis was carried out on a sample of sera from a serum bank used for a vitamin A study. Vaccination coverage was satisfactory (80% or more) in five of nine provinces, although a prevalence of antibody to polio of 80% or more was found in all provinces. Serologic immunity (i.e., the prevalence of neutralizing antibodies) exceeded vaccination coverage, suggesting secondary spread of vaccine virus. However, whether or not water was supplied through a piped system was not associated with secondary spread of vaccine virus to nonvaccinated children. Seroprevalence studies are a valuable adjunct to acute flaccid paralysis surveillance, which is the standard surveillance instrument for the poliomyelitis eradication initiative. The use of available and suitable serum banks for seroprevalence investigations is a relatively cheap monitoring option that can yield very valuable information for the eradication initiative.

A study of the effect of chemical inactivants on the epitopes of Rift Valley fever virus glycoproteins using monoclonal antibodies.

A panel of 23 monoclonal antibodies (mAbs) was used to study the effect of formalin, beta propriolactone (BPL) and binary ethylenimine (BEI) on the epitopes of the Rift Valley fever virus glycoproteins. After the initial inactivation period BEI had very little adverse affect on the epitopes whereas BPL significantly altered seven and formalin partially changed the conformation or accessibility of most of the epitopes. The epitopes of all of the inactivated antigens showed a reduced activity against the specific mAbs over a six month storage period.

Comparison of an antibody-capture IgM enzyme-linked immunosorbent assay with IgM-indirect immunofluorescence for the diagnosis of acute Sindbis and West Nile infections.

The development and evaluation of an antibody-capture ELISA for the detection of IgM antibodies to Sindbis (SIN) and West Nile (WN) viruses are described. Comparison of the ELISA results with those obtained by indirect immunofluorescence (IIF) antibody tests using both fluorescein and biotinylated anti-human IgM conjugates, showed that the former technique was both more sensitive and specific than the IIF methods. There were no false positives by the ELISA whereas with the IgM-IIF assays a high percentage of false positives were obtained. These were due to rheumatoid factor and also to an interfering factor which was not detected by the RF latex agglutination test. Absorption of the sera with anti-IgG was necessary to eliminate this interference in the IgM-IIF tests.

The status of dengue fever virus in South Africa--serological studies and diagnosis of a case of dengue fever.

To assess the possibility of a dengue epidemic occurring in South Africa 3 groups of survey sera and 2 groups of patients' sera, from a dengue high risk area of South Africa, were tested for antibodies to several flaviviruses. 3.8% (75/1951) of the survey sera and 9.2% (26/282) of the patients' sera had haemagglutination inhibition antibodies to one or more of the flaviviruses tested. One of 1951 survey sera had a spectrum of complement fixation antibody consistent with a primary dengue infection, and 5 of 282 patients' sera also had complement fixation antibodies to flavivirus antigens. These 5 positive patients had recently travelled to India but in only one was there an antibody spectrum unequivocably consistent with a primary dengue infection. Dengue virus type 1 was successfully isolated from this patient's acute serum. The susceptibility of the population to dengue virus infection, the presence of the main vector of dengue virus and the occurrence of imported cases of dengue fever emphasize the need for continuous vigilance.

The role of sexual transmission in the epidemiology of hepatitis C virus in black South Africans.

The role of sexual transmission of hepatitis C virus in Black South Africans was evaluated by a seroprevalence study of sentinel populations at varying risk for sexually transmitted diseases (STD). Prevalence of anti-hepatitis C virus antibodies was found to be 1.8% in an STD clinic sample of 272, 0.7% in a family planning sample of 148, 3.3% in a sample of 246 'blue collar' workers (81% of rural origin), and 0.9 in a sample of 117 new blood donors. All samples were from Black adults. The differences between them were not significant (P = 0.2348). In contrast, the prevalence of anti-human immunodeficiency virus antibodies in the STD sample (5.5%) was statistically significantly different (P = 0.00095) from the family planning clinic sample (1.4%) and the blue collar sample (0.8%) as well as from the reported prevalence for black blood donors in the Johannesburg area (0.7%). No evidence supporting a role for sexual transmission of hepatitis C virus was found, while the prevalence of infection appeared to be higher in rural populations and in males. These features are similar to hepatitis B in this population.

Experimental assessment of the vector competence of Culex (Culex) neavei Theobald with West Nile and Sindbis viruses in South Africa.

Culex univittatus is the maintenance vector of West Nile (WN) and Sindbis (SIN) viruses on the inland plateau of South Africa and also transfers infection to man. Both viruses have frequently been isolated from this mosquito and human immunity is high on the plateau. In the Natal lowlands where Cx univittatus is replaced by Cx neavei, apparently the main vector there, immune rates are low and few isolations have been made from this species. Vector competence experiments were carried out with Cx neavei to compare with those previously done with Cx univittatus. It was thought that a difference in such competence might explain the contrasting epidemiological situation in the two regions. After infective feeds on chicks with high viraemias of each virus, Cx neavei showed a high transmission rate. However, the 50% infection thresholds determined by exposing birds with differing viraemias to mosquitoes of this species, were 4.4 logs per ml (WN) and 5.8 logs (SIN). These thresholds are both higher than those for Cx univittatus. It is concluded that Cx neavei is a poorer vector of both viruses which accounts for the lower viral activity, including the lower incidence of human infection, in the Natal lowlands.

The current epidemiology of hepatitis A infection in South Africa: implications for vaccination.

Testing stored sera from various categories of individuals has shown that among the Black population hepatitis A virus (HAV) infection is universal and most adult Black subjects are immune. Infection probably occurs early in life, consistent with the epidemiological pattern seen in the developing world. By contrast, seroprevalence of HAV infection in adult White subjects increases with age, reflecting an epidemiological pattern seen in the developed world. White subjects working in a virological laboratory and White medical students had comparatively low seroprevalences of HAV infection and could therefore represent groups at risk. Hepatitis A vaccine is likely to be available in South Africa in the near future and could be offered to these groups. Pre-vaccination immunity screening would be a cost-effective strategy.