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Background: The coronavirus disease 2019 (COVID-19) pandemic has caused instability in the education system and has compelled higher education institutions (HEIs) to find alternative ways of teaching and learning by making use of the latest online teaching approaches. Aim: The purpose of the study was to explore how COVID-19 could serve as an enabler for the enhancement of online learning and teaching skills for nurse educators at the University of Namibia with specific emphasis on prospects and challenges. Setting: Semi-structured interviews were conducted in English at a public nursing education institution located in the northeast of Namibia. Methods: A qualitative explorative, descriptive and contextual research design was used. Data were collected by means of in-depth semi-structured interviews with 18 nurse educators from the School of Nursing. Data were analysed using thematic analysis. Field notes were simultaneously taken to enrich the data. Results: The study revealed three themes: nurse educators' experiences of the use of online learning and teaching skills, COVID-19 as an enabler for enhancing online learning and teaching skills and strategies to sustain online teaching and learning. Conclusion: Internet technology has generated a surge in demand for web-based teaching and learning. The online learning mode was not effectively utilised during the COVID-19 era because of inadequate technological skills on the part of nurse educators. Contribution: These findings can be used by universities to equip students and academic staff with skills to adapt to e-learning as the new modus operandi in learning and teaching in the post-COVID-19 era.
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The discovery that overexpressing one or a few critical transcription factors can switch cell state suggests that gene regulatory networks are relatively simple. In contrast, genome-wide association studies (GWAS) point to complex phenotypes being determined by hundreds of loci that rarely encode transcription factors and which individually have small effects. Here, we use computer simulations and a simple fitting-free polymer model of chromosomes to show that spatial correlations arising from 3D genome organisation naturally lead to stochastic and bursty transcription as well as complex small-world regulatory networks (where the transcriptional activity of each genomic region subtly affects almost all others). These effects require factors to be present at sub-saturating levels; increasing levels dramatically simplifies networks as more transcription units are pressed into use. Consequently, results from GWAS can be reconciled with those involving overexpression. We apply this pan-genomic model to predict patterns of transcriptional activity in whole human chromosomes, and, as an example, the effects of the deletion causing the diGeorge syndrome.
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Redes Reguladoras de Genes , Genoma Humano , Modelos Genéticos , Fatores de Transcrição/metabolismo , Cromatina/química , Cromatina/metabolismo , Cromossomos Humanos/química , Cromossomos Humanos/metabolismo , Estudo de Associação Genômica Ampla , Humanos , Polímeros/química , Polímeros/metabolismo , Locos de Características Quantitativas , Transcrição GênicaRESUMO
Pararetroviruses, taxon Caulimoviridae, are typical of retroelements with reverse transcriptase and share a common origin with retroviruses and LTR retrotransposons, presumably dating back 1.6 billion years and illustrating the transition from an RNA to a DNA world. After transcription of the viral genome in the host nucleus, viral DNA synthesis occurs in the cytoplasm on the generated terminally redundant RNA including inter- and intra-molecule recombination steps rather than relying on nuclear DNA replication. RNA recombination events between an ancestral genomic retroelement with exogenous RNA viruses were seminal in pararetrovirus evolution resulting in horizontal transmission and episomal replication. Instead of active integration, pararetroviruses use the host DNA repair machinery to prevail in genomes of angiosperms, gymnosperms and ferns. Pararetrovirus integration - leading to Endogenous ParaRetroViruses, EPRVs - by illegitimate recombination can happen if their sequences instead of homologous host genomic sequences on the sister chromatid (during mitosis) or homologous chromosome (during meiosis) are used as template. Multiple layers of RNA interference exist regulating episomal and chromosomal forms of the pararetrovirus. Pararetroviruses have evolved suppressors against this plant defense in the arms race during co-evolution which can result in deregulation of plant genes. Small RNAs serve as signaling molecules for Transcriptional and Post-Transcriptional Gene Silencing (TGS, PTGS) pathways. Different populations of small RNAs comprising 21-24 nt and 18-30 nt in length have been reported for Citrus, Fritillaria, Musa, Petunia, Solanum and Beta. Recombination and RNA interference are driving forces for evolution and regulation of EPRVs.
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BACKGROUND: In the United States, a long-standing debate has existed over advantages/disadvantages of general versus specialty hospitals. A recent stream of research has investigated whether general hospitals accrue performance benefits from a focus strategy; a strategy of specializing in certain clinical conditions while remaining a multiproduct firm. In contrast, a substantial and long-standing body of research on hospitals has been concerned with the absolute volume of cases in a service area as an indication of experience based largely on the idea that absolute volume confers learning opportunities. PURPOSE: We investigated whether hospital focus and experience in a service area have complementary effects or are largely substitutive for hospital performance. METHODOLOGY/APPROACH: Key data sources were patient discharge records and hospital discharge profiles from California's Office of Statewide Health Policy and Development for years 2010-2014. We specified hospital focus as the proportion of total cardiology-related discharges and hospital experience as the cumulative volume of cardiology-related discharges for each hospital. Performance was specified using quality (inpatient mortality and 30-day readmission) and efficiency (length of stay and cost) patient-level performance metrics. We analyzed the data using logistic and log-linear ordinary least squares regression models. RESULTS: Study results generally supported our hypotheses that focus and experience are related to better quality and efficiency performance and that the effects are largely substitutive for hospitals. CONCLUSION: Our study extends the literature by finding that hospitals exhibit distinct and stable patterns regarding their positioning on focus and experience and that these patterns have important implications for hospitals' performance in terms of quality and efficiency. PRACTICE IMPLICATIONS: Many general hospitals in the United States may be stretched too thin across service areas for which they lack necessary patient volumes for clinical proficiency. A viable alternative is to select a limited set of service areas on which to focus.
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Hospitais , Alta do Paciente , Humanos , Pacientes Internados , Estados UnidosRESUMO
Microbial processes are critical to the function of freshwater ecosystems, yet we still do not fully understand the factors that shape freshwater microbial communities. Furthermore, freshwater ecosystems are particularly susceptible to effects of environmental change, including influx of exogenous nutrients such as nitrogen and phosphorus. To evaluate the impact of nitrogen loading on the microbial community structure of shallow freshwater lakes, water samples collected from Lake Shenandoah (Virginia, USA) were incubated with two concentrations of either ammonium, nitrate, or urea as a nitrogen source. The potential impact of these nitrogen compounds on the bacterial community structure was assessed via 16S rRNA amplicon sequencing. At the phylum level, the dominant taxa in Lake Shenandoah were comprised of Actinobacteria and Proteobacteria, which were not affected by exposure to the various nitrogen treatments. Overall, there was not a significant shift in the diversity of the bacterial community of Lake Shenandoah with the addition of nitrogen sources, indicating this shallow system may be constrained by other environmental factors.
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Lagos , Nitrogênio , Bactérias , Proteobactérias , RNA Ribossômico 16SRESUMO
BACKGROUND: The development of a nurse-led approach to managing epilepsy in adults with an intellectual disability (ID) offers the potential of improved outcomes and lower costs of care. We undertook a cluster randomised trial to assess the impact on costs and outcomes of the provision of ID nurses working to a designated epilepsy nurse competency framework. Here, we report the impact of the intervention on costs. METHOD: Across the United Kingdom, eight sites randomly allocated to the intervention recruited 184 participants and nine sites allocated to treatment as usual recruited 128 participants. Cost and outcome data were collected mainly by telephone interview at baseline and after 6 months. Total costs at 6 months were compared from the perspective of health and social services and society, with adjustments for pre-specified participant and cluster characteristics at baseline including costs. Missing data were imputed using multiple imputation. Uncertainty was quantified by bootstrapping. RESULTS: The intervention was associated with lower per participant costs from a health and social services perspective of -£357 (2014/2015 GBP) (95% confidence interval -£986, £294) and from a societal perspective of -£631 (95% confidence interval -£1473, £181). Results were not sensitive to the exclusion of accommodation costs. CONCLUSIONS: Our findings suggest that the competency framework is unlikely to increase the cost of caring for people with epilepsy and ID and may reduce costs.
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Competência Clínica , Serviços de Saúde Comunitária , Epilepsia/terapia , Custos de Cuidados de Saúde , Deficiência Intelectual/terapia , Enfermeiras e Enfermeiros , Equipe de Assistência ao Paciente , Avaliação de Processos em Cuidados de Saúde , Adulto , Comorbidade , Epilepsia/epidemiologia , Humanos , Deficiência Intelectual/epidemiologiaRESUMO
The triplet excited state of thioxanthone produced by photolysis undergoes reversible triplet energy transfer with a trimethylene-linked benzothiophene-2-carboxanilide ring system. The ensuing electrocyclic ring closure of the anilide moiety produces a putative zwitterionic intermediate that is capable of expelling leaving groups (LG-) from the C-3 position of the benzothiophene ring. Stern-Volmer quenching studies with cyclohexadiene as quencher furnish the rate constants for the triplet excitation transfer in the forward and reverse directions, which can be expressed as an equilibrium constant K = 0.058. Overall, the rate of the triplet excited state reaction becomes K × kr = 5.7 × 104 s-1 for LG- = Cl-, where kr is the triplet decay rate of the C-3 chloro-substituted benzothiophene-2-carboxanilide, found through Stern-Volmer quenching. The high quantum efficiencies found for the trimethylene-linked systems are due to K × kr being competitive with the triplet excited state decay of the thioxanthone of kd = 7.7 × 104 s-1. On the basis of Φisc = 0.68, the overall expected quantum yield for direct photolysis should be 0.50 for LG- = Cl- as compared to 0.41 at 25 °C experimentally. Φ decreases with increasing basicity of the leaving group (LG- = Cl-, (EtO)2PO2-, PhCH2CO2-, PhS-, and PhCH2S-).
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OBJECTIVE: Mindfulness-based interventions have been shown to have psychological benefits in college students. We explored the effects of an academic Seminar on Compassion on student psychological health. PARTICIPANTS: Forty-one participants (14 male, 27 female, mean age 19.8 ± 1.4 years) were assessed pre- and post- spring semesters 2013 and 2014. METHODS: Students were randomized to the Seminar on Compassion or a wait-list control group. Participants completed self-report measures on anxiety, depression, perceived stress, self-compassion, compassion and mindfulness. Salivary alpha-amylase was also assessed. RESULTS: At baseline, self-compassion and mindfulness were negatively correlated with depression, anxiety, and perceived stress. There were significant changes between the intervention and control group from Time 1 to Time 2 in mindfulness, self-compassion, compassion, and salivary alpha-amylase; however, there were no significant changes in depression, anxiety, and perceived stress. CONCLUSIONS: The course was effective in increasing mindfulness, self-compassion and compassion, and decreasing a salivary marker of stress.
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Empatia , Saúde Mental/estatística & dados numéricos , Atenção Plena/educação , Estudantes/psicologia , Adolescente , Ansiedade/epidemiologia , Depressão/epidemiologia , Feminino , Humanos , Masculino , Autorrelato , Estresse Psicológico/epidemiologia , Universidades , Adulto Jovem , alfa-Amilases/análiseRESUMO
Endosalpingiosis of the urinary bladder is a rare benign condition characterised by the presence of ectopic endosalpingeal tissue in the bladder. If histology shows two or more Müllerian-derived components, this condition is referred to as Müllerianosis.To our knowledge less than 20 cases of Müllerianosis and 5 cases of endosalpingiosis have been documented in the literature.Although the pathogenesis remains unclear, two theories exist. The implantation theory assumes that Müllerian-derived tissue gets implanted in the wall of the urinary bladder during pelvic surgery. The second theory proposes a metaplastic origin of the disease.Patients suffering from endosalpingiosis or Müllerianosis may present with symptoms such as suprapubic pain, frequent urination, dysuria or gross haematuria, possibly with a cyclical appearance.We present the case of a 40-year-old female patient, who primarily presented with painful haematuria and was diagnosed with endosalpingiosis and treated by transurethral resection. Also we review the current literature.
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Doenças da Bexiga Urinária/diagnóstico , Doenças da Bexiga Urinária/cirurgia , Procedimentos Cirúrgicos Urológicos/métodos , Adulto , Coristoma/patologia , Feminino , HumanosRESUMO
Between 15 and 20% of patients diagnosed with renal cell carcinoma suffer from metastatic disease by the time of diagnosis. In the immunotherapy era, the standard treatment was to perform cytoreductive nephrectomy (CN) followed by treatment with interferon α. This was based on two prospective randomized trials and their combined analysis. Since the introduction of targeted therapy, the use of CN came into question and the number of performed CN has declined. Two trials (CARMENA and SURTIME) evaluating the role of CN in the times of targeted therapy have either closed early or are recruiting slowly and will probably not be able to answer this question. Thus, we need to focus on retrospective data consisting of several analyses with large numbers of patients. These analyses all seem to show a benefit in overall survival, and adjusted for prognostic factors CN represents an independent predictor of longer survival. A correlation between expected life span and efficacy of CN has been shown with a survival rate that is three times higher after 3 years. Only patients with low performance status, low life expectancy, cerebral metastases, and old age did not benefit from CN. Furthermore, symptom control of large primary tumors without response to systemic therapy and the fact that all reports of long-term remission or long survival rates are associated with the use of CN are theoretical aspects speaking in favor of this treatment. This leads to the recommendation to perform CN in all patients with good performance status in all important guidelines.
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Carcinoma de Células Renais/secundário , Carcinoma de Células Renais/cirurgia , Procedimentos Cirúrgicos de Citorredução/estatística & dados numéricos , Neoplasias Renais/mortalidade , Neoplasias Renais/cirurgia , Recidiva Local de Neoplasia/mortalidade , Nefrectomia/estatística & dados numéricos , Carcinoma de Células Renais/mortalidade , Tomada de Decisão Clínica/métodos , Procedimentos Cirúrgicos de Citorredução/mortalidade , Medicina Baseada em Evidências , Feminino , Humanos , Neoplasias Renais/patologia , Metástase Linfática , Masculino , Recidiva Local de Neoplasia/prevenção & controle , Nefrectomia/mortalidade , Prevalência , Taxa de Sobrevida , Resultado do TratamentoRESUMO
We propose a stochastic model for gene transcription coupled to DNA supercoiling, where we incorporate the experimental observation that polymerases create supercoiling as they unwind the DNA helix and that these enzymes bind more favorably to regions where the genome is unwound. Within this model, we show that when the transcriptionally induced flux of supercoiling increases, there is a sharp crossover from a regime where torsional stresses relax quickly and gene transcription is random, to one where gene expression is highly correlated and tightly regulated by supercoiling. In the latter regime, the model displays transcriptional bursts, waves of supercoiling, and up regulation of divergent or bidirectional genes. It also predicts that topological enzymes which relax twist and writhe should provide a pathway to down regulate transcription.
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DNA Super-Helicoidal , Transcrição Gênica , Ativação Transcricional , Regiões Promotoras GenéticasRESUMO
Therapeutic strategies have been reported that depend on synthetic network devices in which a urate-sensing transcriptional regulator detects pathological levels of urate and triggers production or release of urate oxidase. The transcription factor involved, HucR, is a member of the multiple antibiotic resistance (MarR) protein family. We show that protonation of stacked histidine residues at the pivot point of long helices that form the scaffold of the dimer interface leads to reversible formation of a molten globule state and significantly attenuated DNA binding at physiological temperatures. We also show that binding of urate to symmetrical sites in each protein lobe is communicated via the dimer interface. This is the first demonstration of regulation of a MarR family transcription factor by pH-dependent interconversion between a molten globule and a compact folded state. Our data further suggest that HucR may be utilized in synthetic devices that depend on detection of pH changes.
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DNA/química , DNA/metabolismo , Histidina , Concentração de Íons de Hidrogênio , Dobramento de Proteína , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Sítios de Ligação , DNA/genética , Histidina/metabolismo , Ligantes , Modelos Moleculares , Conformação Molecular , Ligação Proteica , TermodinâmicaRESUMO
Cytomegalovirus (CMV) is the leading cause of congenital infection and non-genetic sensorineural hearing loss in children. There are no recent data on the incidence of CMV infection during pregnancy in Canada. This present study was undertaken to determine the seroprevalence of CMV IgG antibodies and the rate of seroconversion in a cohort of pregnant women in the province of Québec, Canada. We used serum samples and questionnaire data collected as part of the 3D Pregnancy and Birth Cohort Study (2010-2013) conducted in Québec, Canada. CMV IgG antibodies were determined in serum samples collected at the first and third trimesters. Associations between independent variables and seroprevalence were assessed using logistic regression, and associations with seroconversions, by Poisson regression. Of 1938 pregnant women tested, 40·4% were seropositive for CMV at baseline. Previous CMV infection was associated with: working as a daycare educator, lower education, lower income, having had children, first language other than French or English, and being born outside Canada or the United States. Of the 1122 initially seronegative women, 24 (2·1%) seroconverted between their first and third trimesters. The seroconversion rate was 1·4 [95% confidence interval (CI) 0·9-2·1]/10 000 person-days at risk or 3·9 (95% CI 2·5-5·9)/100 pregnancies (assuming a 280-day gestation). The high proportion of pregnant women susceptible to CMV infection (nearly 60%) and the subsequent rate of seroconversion are of concern.
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Infecções por Citomegalovirus/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Soroconversão , Adolescente , Adulto , Anticorpos Antivirais/sangue , Feminino , Humanos , Imunoglobulina G/sangue , Incidência , Pessoa de Meia-Idade , Gravidez , Estudos Prospectivos , Quebeque/epidemiologia , Estudos Soroepidemiológicos , Inquéritos e Questionários , Adulto JovemRESUMO
BACKGROUND: As hospital employment of physicians becomes increasingly common in the United States, much speculation exists as to whether this type of arrangement will promote hospital operating efficiency in such areas as supply chain management. Little empirical research has been conducted to address this question. PURPOSE: The aim of this study was to provide an exploratory assessment of whether hospital employment of physicians is associated with better supply chain performance. Drawing from both agency and stewardship theories, we examined whether hospitals with a higher proportion of employed medical staff members have relatively better supply chain performance based on two performance measures, supply chain expenses and inventory costs. APPROACH: We conducted the study using a pooled, cross-sectional sample of hospitals located in California between 2007 and 2009. Key data sources were hospital annual financial reports from California's Office of Statewide Health Policy and Development and the American Hospital Association annual survey of hospitals. To examine the relationship between physician employment and supply chain performance, we specified physician employment as the proportion of total employed medical staff members as well as the proportion of employed medical staff members within key physician subgroups. We analyzed the data using generalized estimating equations. FINDINGS: Study results generally supported our hypothesis that hospital employment of physicians is associated with better supply chain performance. PRACTICAL IMPLICATIONS: Although the results of our study should be viewed as preliminary, the trend in the United States toward hospital employment of physicians may be a positive development for improved hospital operating efficiency. Hospital managers should also be attentive to training and educational resources that medical staff members may need to strengthen their role in supply chain activities.
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Emprego , Equipamentos e Provisões Hospitalares , Administração de Materiais no Hospital/organização & administração , Corpo Clínico Hospitalar , California , Estudos Transversais , Pesquisa Empírica , Estudos de Casos Organizacionais , Análise de Regressão , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Genetic material from large patient cohorts is increasingly central to translational genetic research. However, patient blood samples are a finite resource and their supply and storage are often dictated by clinical and not research protocols. Our experience supports difficulty in amplifying DNA from blood stored in herparin; a scenario that other researchers may have or will encounter. This technical note describes a number of simple steps that enable successful PCR amplification. METHODS: DNA was extracted using the Illustra Nucleon Genomic DNA Extraction Kit. PCR amplification was attempted using a number of commercially available PCR mastermixes. RESULTS: PCR DNA amplification failed using ReddyMix™ PCR Master Mix, Thermo-Start® (Thermo Scientific Inc. US) and ZymoTaq™ (Zymo research, US) PCR mastermixes, as demonstrated absence of products on gel electrophoresis. However, using the Invitrogen™ (Thermo Scientific Inc., US) Platinum® Taq DNA Polymerase, PCR products were identified on a 1% agarose gel for all samples. PCR products were cleaned with ExoSAP-IT® (Affymetrix Inc., US) and a sequencing reaction undertaken using a standard Big Dye protocol. Subsequent genotyping was successful for all samples for alleles at the CDH1 locus. CONCLUSION: From our experience a standard phenol/chloroform purification and using the Invitrogen™ Platinum® Taq has enabled the amplification of whole blood samples taken into lithium heparin and stored frozen for up to a month. This simple method may enable investigators to utilise blood taken in lithium heparin for DNA extraction and amplification.
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DNA/análise , DNA/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Manejo de Espécimes/métodos , Sangue/efeitos dos fármacos , Amplificação de Genes , Heparina/farmacologia , HumanosRESUMO
BACKGROUND: The World Health Organisation has recommended the use of anthropometric measurements as birth weight surrogates. However, it has been found that cut-off points for these anthropometric measurements vary across nations and ethnic groups. OBJECTIVES: To determine the predictive values of chest circumference (CC), occipito-frontal circumference (OFC) and their combinations for low birth weight (LBW) detection in Igbo newborns. METHODS: Live newborns of Igbo origin were recruited within 24 hours of delivery. Their CC, OFC and weight were measured. Cut off points for predicting low birth weight was determined using ROC analysis. RESULTS: A total of 511 live newborns were recruited. For birth weight <2500 g, cut-off values were: CC 30.9 cm; OFC 33.8 cm; summation of CC and OFC 64.9 cm; ratio of CC to OFC 0.92. For weight <2000 g, the cut-off values were: CC 29.6 cm; OFC 32.8 cm; summation of CC and OFC 63.7 cm; ratio of CC to OFC 0.91. CC correlated best with birth weight (r = 0.918). CONCLUSION: CC is the best predictor for LBW.
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Etnicidade , Recém-Nascido de Baixo Peso , Crânio/anatomia & histologia , Tórax/anatomia & histologia , Cefalometria , Estudos Transversais , Humanos , Recém-Nascido , Nigéria , Valor Preditivo dos TestesRESUMO
The purpose of this study was to investigate risk factors that could promote HIV infection amongst adolescents and young adults living in tertiary educational institutional hostels in Namibia. Employing structured questionnaires and focus group discussions, we sought to answer questions pertaining to factors, beliefs systems, values, traditions and sexual relations that could promote HIV infection in the student hostels. The data on these issues were gathered from 306 male and 314 female students aged 18-35 years living in eight hostels. Amongst other results, the data revealed that sexual promiscuity in the hostels was treated as the norm in the majority of cases, unauthorized access to hostel rooms by non-hostel dwellers was rampant, sexual harassment of female students by men who were under the influence of alcohol was reported to be common and there was general lack of support for victims of sexual abuse in the hostels. In addition, there was a general sense of insecurity in the hostels where more than 50% of the participants were afraid of being sexually attacked, some female hostel residents engaged in sexual activities for monetary and material gain and there was a general practice of older men from the community having sexual relations with young female hostel dwellers. To mitigate these and other risks it is recommended that there be provision of more HIV/AIDS prevention services, enhanced security, non-toxic entertainment (e.g. participation in sport and social clubs) and the banning of the sale of alcohol in student residences and on tertiary institution campuses. These and other results are discussed in the article and ways of mitigating the risks are proposed.
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Infecções por HIV/prevenção & controle , Habitação , Universidades/estatística & dados numéricos , Adolescente , Adulto , Feminino , Grupos Focais , Infecções por HIV/epidemiologia , Infecções por HIV/etiologia , Habitação/estatística & dados numéricos , Humanos , Masculino , Namíbia/epidemiologia , Prevalência , Estupro , Fatores de Risco , Segurança , Inquéritos e Questionários , Adulto JovemRESUMO
Colloid chemistry (κολλα: glue, or gelatin) was introduced in 1861 after the discovery of protoplasm, which exhibits gelatin-like properties. Some 80 years later, colloid chemistry (and with it, the concept of protoplasm) was largely abandoned. The membrane (pump) theory, according to which cell water and cell solute like K+ are free as in a dilute KC1 solution, became dominant. Later studies revealed that rejecting the protoplasmic approach to cell physiology was not justified. Evidence against the membrane (pump) theory, on the other hand, has stood the test of time. In a new theory of the living cell called the association-induction (AI) hypothesis, the three major components of the living cell (water, proteins and K+) are closely associated; together they exist in a high- (negative)-energy-low entropy state called the living state. The bulk of cell water is adsorbed as polarized multilayers on some fully extended protein chains, and K+ is adsorbed singly on ß- and γ-carboxyl groups carried on aspartic and glutamic residues of cell proteins. Extensive evidence in support of the AI hypothesis is reviewed. From an extension of the basic concepts of the AI hypothesis and the new knowledge on primary structure of the proteins, one begins to understand at long last what distinguishes gelatin from other proteins; in this new light, new definitions of protoplasm and of colloid chemistry have been introduced. With the return of the concept of protoplasm, living structure takes on renewed significance, linking cell anatomy to cell physiology. Finally, evidence is presented showing that electron microscopists have come close to seeing cell structure in its living state.
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Fenômenos Fisiológicos Celulares/fisiologia , Citoplasma , Proteínas , Água , Bioquímica , Coloides , Citoplasma/química , Citoplasma/fisiologia , Microscopia Eletrônica , Potássio/fisiologia , Proteínas/química , Proteínas/fisiologia , Água/química , Água/fisiologiaRESUMO
BACKGROUND: Congenital abnormalities are not uncommon among newborns and contribute to neonatal and infant morbidity and mortality. The prevalence and pattern of presentation vary from place to place. Many a time the exact etiology is unknown but genetic and environmental factors tend to be implicated. METHODS: The objective of this study was to determine the prevalence of congenital malformations among newborns admitted in a tertiary hospital in Enugu, the nature of these abnormalities and the outcome/prognosis. For purposes of this study, congenital abnormalities are defined as obvious abnormality of structure or form which is present at birth or noticed within a few days after birth. A cross-sectional retrospective study in which a review of the records of all babies admitted in the Newborn Special Care Unit (NBSCU) of the University of Nigeria Teaching Hospital (UNTH), Ituku/Ozalla, Enugu over a four year period (January 2007-April 2011) was undertaken.All babies admitted in the unit with the diagnosis of congenital abnormality were included in the study. Information extracted from the records included characteristics of the baby, maternal characteristics, nature/type of abnormalities and outcome.Data obtained was analyzed using SPSS 13. Rates and proportions were calculated with 95% confidence interval. The proportions were compared using students T-test. Level of significance was set at P < 0.05 RESULTS: Seventeen (17) out of a total of six hundred and seven newborn babies admitted in the newborn unit of UNTH over the study period (Jan 2007-March 2011) were found to have congenital abnormalities of various types, giving a prevalence of 2.8%. Common abnormalities seen in these babies were mainly surgical birth defects and included cleft lip/cleft palate, neural tube defects (occurring either singly or in combination with other abnormalities), limb abnormalities (often in combination with neural tube defects of various types), omphalocoele, umbilical herniae, ano-rectal malformations and dysmorphism associated with multiple congenital abnormalities. CONCLUSIONS: The results of this study show that 2.8% of babies admitted to a Newborn Special Care Unit in a teaching hospital in Enugu had congenital abnormalities and that the commonest forms seen were mainly surgical birth defects and includes cleft lip/cleft palate and neural tube defects.