The psbC start codon in Synechocystis sp. PCC 6803

AbstractThe translation start codon for psbC, the gene encoding CP43, a chlorophyll-binding protein of photosystem II, has been identified for the cyanobacterium Synechosystis sp. PCC 6803 using site-directed mutagenesis. An AUG codon, about 50 bases upstream from the end of psbD-I had previously been assumed to be the translation start site of psbC. However, the fact that the AUG codon is not present in psbC from several other organisms, whereas a GUG codon 14 bases upstream from the end of psbD-I is strictly conserved suggests that CP43 translation starts at the latter codon. Mutation of GUG, but not of AUG, led to a loss of CP43 and photoautotrophic growth, indicating that the GUG codon is the sole initiation site for translation of the CP43 protein in Synechocystis sp. PCC 6803

Reference points and redistributive preferences: experimental evidence

https://sites.bu.edu/fisman/files/2022/10/draft_ref_points_JPubEc_revised_sept2022.pd

Evidence for the prepattern/cooption model of vertebrate jaw evolution

The appearance of jaws was a turning point in vertebrate evolution because it allowed primitive vertebrates to capture and process large, motile prey. The vertebrate jaw consists of separate dorsal and ventral skeletal elements connected by a joint. How this structure evolved from the unjointed gill bar of a jawless ancestor is an unresolved question in vertebrate evolution. To understand the developmental bases of this evolutionary transition, we examined the expression of 12 genes involved in vertebrate pharyngeal patterning in the modern jawless fish lamprey. We find nested expression of Dlx genes, as well as combinatorial expression of Msx, Hand and Gsc genes along the dorso-ventral (DV) axis of the lamprey pharynx, indicating gnathostome-type pharyngeal patterning evolved before the appearance of the jaw. In addition, we find that Bapx and Gdf5/6/7, key regulators of joint formation in gnathostomes, are not expressed in the lamprey first arch, whereas Barx, which is absent from the intermediate first arch in gnathostomes, marks this domain in lamprey. Taken together, these data support a new scenario for jaw evolution in which incorporation of Bapx and Gdf5/6/7 into a preexisting DV patterning program drove the evolution of the jaw by altering the identity of intermediate first-arch chondrocytes. We present this “Pre-pattern/Cooption” model as an alternative to current models linking the evolution of the jaw to the de novo appearance of sophisticated pharyngeal DV patterning

Occupational health risks associated with medical waste management practices among health professionals working in three district hospitals in Rwanda

Background: Proper healthcare waste management is crucial to minimize the exposure of health professionals, patients, and the public in general, and to reduce the pollution of the environment in particular. In Rwanda, scientific documents on occupational health risks resulting from medical waste management practices among healthcare workers are currently rare.Aim: This study aimed to explore occupational health risks associated with medical waste management practices among health professionals in the Rwandan context.Method: A cross-sectional study design was used. The study used both quantitative and qualitative methods. The respondents were composed of health professionals (medical doctors, nurses, and paramedical staff) from the district hospital and six key informants. We used questionnaire, interview guide, and observation checklists as research instruments. We performed descriptive statistics to analyze the quantitative data. Also, qualitative data were analyzed using narrative analysis method.Results: The findings revealed that 56.5 % of respondents from Kibagabaga hospital, 26.8% from Masaka and 49.3% from Muhima Hospital reported that they experienced occupational health risks related to inadequate medical waste management at their workplaces, and some of those risks include risk of infection and physical injuries.Conclusion: This study concludes that health professionals working in health facilities in Rwanda are exposed to the risks resulting from poor medical waste management practices. Thus, the study recommends putting more emphasis on raising awareness of staff towards risks resulting from poor medical waste management practices.Keywords: Occupational health risk; Medical waste; Health professionals, Hospital, Healthcare wast

The Implementation of the Stay Home Measure and its Effectiveness in Containing the Spread of 2019-nCoV in East African Countries: Case of Rwanda, and Kenya

A novel coronavirus (2019-nCoV), is a new public health issue that is threatening the entire world. The first cases were detected in China by the end of 2019 and spread worldwide rapidly. A significant number of hospitalization and deaths have been recorded globally. So far, Public health measures, including staying at home, are the only available efficient control measures that help to stop the spread of the disease. This paper aims to document how the stay home measure was implemented and highlight its effects on the prevention of the spread of the disease in Rwanda and Kenya. The selection of Kenya and Rwanda was based on the fact that authors able to access the daily report from these countries. The authors reviewed the available literature to inform their views. In Rwanda, the stay-home strategy was strictly enforced, and movements were highly restricted, while in Kenya, movements were allowed in some counties with respect to preventive measures in place.  The authors of this paper conclude that the stay home measure is a key measure to the containment of the spread of the outbreak. The paper recommends further studies to document the statistical association between the mode of implementation of the stay home measure and the decrease of new cases of 2019-nCoV. Rwanda J Med Health Sci 2020;3(3):362-37

Increased burden of familial-associated early-onset cancer risk among minority americans compared to non-latino whites

Background: The role of race/ethnicity in genetic predisposition of early-onset cancers can be estimated by comparing family-based cancer concordance rates among ethnic groups. Methods: We used linked California health registries to evaluate the relative cancer risks for first-degree relatives of patients diagnosed between ages 0 and 26, and the relative risks of developing distinct second primary malignancies (SPMs). From 1989 to 2015, we identified 29,631 cancer patients and 62,863 healthy family members. We calculated the standardized incident ratios (SIRs) of early-onset primary cancers diagnosed in proband siblings and mothers, as well as SPMs detected among early-onset patients. Analyses were stratified by self-identified race/ethnicity. Results: Given probands with cancer, there were increased relative risks of any cancer for siblings and mothers (SIR = 3.32; 95% confidence interval [CI]: 2.85–3.85) and of SPMs (SIR = 7.27; 95% CI: 6.56–8.03). Given a proband with solid cancer, both Latinos (SIR = 4.98; 95% CI: 3.82–6.39) and non-Latino Blacks (SIR = 7.35; 95% CI: 3.36–13.95) exhibited significantly higher relative risk of any cancer in siblings and mothers when compared to non-Latino White subjects (SIR = 3.02; 95% CI: 2.12–4.16). For hematologic cancers, higher familial risk was evident for Asian/Pacific Islanders (SIR = 7.56; 95% CI: 3.26–14.90) compared to non-Latino whites (SIR = 2.69; 95% CI: 1.62–4.20). Conclusions: The data support a need for increased attention to the genetics of early-onset cancer predisposition and environmental factors in race/ethnic minority families in the United States.</p

Clinical signs associated with earlier diagnosis of children with autism Spectrum disorder

Background The objective of this study is to gain new insights into the relationship between clinical signs and age at diagnosis. Method We utilize a new, large, online survey of 1743 parents of children diagnosed with ASD, and use multiple statistical approaches. These include regression analysis, factor analysis, and machine learning (regression tree). Results We find that clinical signs that most strongly predict early diagnosis are not necessarily specific to autism, but rather those that initiate the process that eventually leads to an ASD diagnosis. Given the high correlations between symptoms, only a few signs are found to be important in predicting early diagnosis. For several clinical signs we find that their presence and intensity are positively correlated with delayed diagnosis (e.g., tantrums and aggression). Even though our data are drawn from parents’ retrospective accounts, we provide evidence that parental recall bias and/or hindsight bias did not play a significant role in shaping our results. Conclusion In the subset of children without early deficits in communication, diagnosis is delayed, and this might be improved if more attention will be given to clinical signs that are not necessarily considered as ASD symptoms. Our findings also suggest that careful attention should be paid to children showing excessive tantrums or aggression, as these behaviors may interfere with an early ASD diagnoses