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Polyhydroxyalkanoates (PHAs) are synthesized by a variety of microorganisms as intracellular storage granules under imbalanced nutrition and excess carbon. Carbon sources are key contributors to the high cost of PHA production, hence the need for exploration of cheap and sustainable raw materials for bacteria fermentation. In the present study, Halomonas alkalicola strain Ext isolated from a hypersaline lake in Kenya was assessed for its ability to utilize fruit peels hydrolysates (FPH) as sole carbon sources for PHA production. Sugars were extracted from dried peels of banana, mango, orange, and pineapple fruits through mechanical pretreatment and dilute acid hydrolysis. Fruit peels pretreated with 3 % H2SO4 at 121℃ were utilized for shake flask fermentation to produce PHAs by Halomonas alkalicola Ext. At optimal C:N ratios of between 20:1 and 30:1, the bacterium could produce up to 0.45±0.03, 0.394±0.12, 0.39±0.05, and 0.28±0.0 g/L of PHAs from hydrolysates of orange peels, mango peels, banana peels, and pineapple peels, respectively. A maximum PHA content of 16.92 % was achieved on orange peels hydrolysates with 4 % substrate loading. Monomer analysis with gas chromatography-mass spectrometry (GC-MS) revealed that the bacterium produced a copolymer Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) with 3-hydroxyvalerate (3HV) contents of 5.77 %, 6.08 %, 6.79 %, 6.845 %, for orange peels, pineapple peels, mango peels and banana peels substrates, respectively. The findings of this study suggest that fruit peels waste is a potential feedstock for sustainable production of PHAs by Halomonas alkalicola.

Abstract Spatial transcriptomics (ST) technologies enable high throughput gene expression characterization within thin tissue sections. However, comparing spatial observations across sections, samples, and technologies remains challenging. To address this challenge, we develop STalign to align ST datasets in a manner that accounts for partially matched tissue sections and other local non-linear distortions using diffeomorphic metric mapping. We apply STalign to align ST datasets within and across technologies as well as to align ST datasets to a 3D common coordinate framework. We show that STalign achieves high gene expression and cell-type correspondence across matched spatial locations that is significantly improved over landmark-based affine alignments. Applying STalign to align ST datasets of the mouse brain to the 3D common coordinate framework from the Allen Brain Atlas, we highlight how STalign can be used to lift over brain region annotations and enable the interrogation of compositional heterogeneity across anatomical structures. STalign is available as an open-source Python toolkit at https://github.com/JEFworks-Lab/STalign and as Supplementary Software with additional documentation and tutorials available at https://jef.works/STalign .

In the wake of climate change and dwindling natural resources, system of rice intensification has been fronted as an approach to improve rice production in several countries. Besides the benefits such as improved rice productivity, reduced water usage that have widely been observed, there is need to quantify the economic benefits of system of rice intensification accrued to farmers, thereby promoting it as an innovation to improve livelihoods of rice farmers. This aim of this paper is to quantify the economic benefits of undertaking SRI among smallholder rice farmers. We introduced SRI among smallholder farmers in a rural setting in western Kenya, Oluch irrigation scheme, through an innovation platform approach. Over the period of four years (2016-2019), we quantify the benefits accrued to the uptake of the technology among adopters of the technology. Our comparisons are in reference to a baseline study conducted prior to the full-scale promotion of SRI in the study area. Our study findings reveal that the uptake of specific SRI practices increased by at least 30-80%, and acreage under rice farming increased by 50%. Besides, SRI required more production costs per acre (63% increase), although SRI had at least 28.6% higher return per shilling invested. Our findings underscore previous results in the literature that SRI is associated with not only productivity but also economic benefits justifying the need for scaling especially among smallholder farmers. Nonetheless, efficient approaches to scaling such promising technologies are necessary to enhance productivity and subsequently improve livelihoods.

Polyhydroxyalkanoates (PHAs) are biodegradable and biocompatible polymers that are produced by microorganisms as storage materials under limited nutrition and excess carbon. These PHAs have been found to be ideal for replacing synthetic plastics for use in packaging and biomedical applications. In this study, an alkaliphilic and moderately halophilic bacterium Halomonas alkalicola Ext was isolated from Lake Simbi Nyaima in western Kenya and investigated for PHA production. Sudan Black B and Nile Red A staining showed that bacterium had distinct ability for accumulation of PHAs. To optimize PHA production, the bacterium was grown in submerged fermentation under varying culture conditions and different sources and concentrations of carbon and nitrogen. With one-factor-at-a-time (OFTA) approach, optimal PHA yields were obtained after 72 hours at a pH of 10.0, temperature of 35°C, and 2.5% (w/v) NaCl. The bacterium yielded the highest biomass, and PHA amounts on 2% galactose and 0.1% ammonium sulfate as sources of carbon and nitrogen, respectively. A record PHA yield of 0.071 g g-1 with a titer of 1.419±0.09 g/L was achieved from 3.397 g/L of biomass, equivalent to 41.8% PHA content. Using response surface methodology, PHA titer was increased by 1.5% to 1.44 g/L, while PHA content was improved 1.1-fold to 45.57%. Polymer analysis revealed that the extracted PHA was a poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) (3−HB:3−HV=92:8) with two copolymer subunits of 3-hydroxyvaryrate (3-HB) and 3-hydroxybutyrate (3-HV). Halomonas alkalicola Ext attained efficient galactose conversion into PHBV under high salinity and alkalinity conditions.

Extremophilic microorganisms such as those that thrive in high-salt and high-alkaline environments are promising candidates for the recovery of useful biomaterials including polyhydroxyalkanoates (PHAs). PHAs are ideal alternatives to synthetic plastics because they are biodegradable, biocompatible, and environmentally friendly. This work was aimed at conducting a bioprospection of bacteria isolated from hypersaline-alkaliphilic lakes in Kenya for the potential production of PHAs. In the present study, 218 isolates were screened by Sudan Black B and Nile Red A staining. Of these isolates, 31 were positive for PHA production and were characterized using morphological, biochemical, and molecular methods. Through 16S rRNA sequencing, we found that the isolates belonged to the genera Arthrobacter spp., Bacillus spp., Exiguobacterium spp., Halomonas spp., Paracoccus spp., and Rhodobaca spp. Preliminary experiments revealed that Bacillus sp. JSM-1684023 isolated from Lake Magadi had the highest PHA accumulation ability, with an initial biomass-to-PHA conversion rate of 19.14% on a 2% glucose substrate. Under optimized fermentation conditions, MO22 had a maximum PHA concentration of 0.516 g/L from 1.99 g/L of cell dry weight and 25.9% PHA conversion, equivalent to a PHA yield of 0.02 g/g of biomass. The optimal PHA production media had an initial pH of 9.0, temperature of 35 °C, salinity of 3%, and an incubation period of 48 h with 2.5% sucrose and 0.1% peptone as carbon and nitrogen sources, respectively. This study suggests that bacteria isolated from hypersaline and alkaliphilic tropical lakes are promising candidates for the production of polyhydroxyalkanoates.

How have complex brains evolved from simple circuits? Here we investigated brain region evolution at cell-type resolution in the cerebellar nuclei, the output structures of the cerebellum. Using single-nucleus RNA sequencing in mice, chickens, and humans, as well as STARmap spatial transcriptomic analysis and whole-central nervous system projection tracing, we identified a conserved cell-type set containing two region-specific excitatory neuron classes and three region-invariant inhibitory neuron classes. This set constitutes an archetypal cerebellar nucleus that was repeatedly duplicated to form new regions. The excitatory cell class that preferentially funnels information to lateral frontal cortices in mice becomes predominant in the massively expanded human lateral nucleus. Our data suggest a model of brain region evolution by duplication and divergence of entire cell-type sets.

Which neural circuits undergo synaptic changes when an animal learns? Although it is widely accepted that changes in synaptic strength underlie many forms of learning and memory, it remains challenging to connect changes in synaptic strength at specific neural pathways to specific behaviors and memories. Here we introduce SYNPLA (synaptic proximity ligation assay), a synapse-specific, high-throughput, and potentially brain-wide method capable of detecting circuit-specific learning-induced synaptic plasticity.

Abstract Osteoporosis is a systemic bone disease that affects more than 200 million people worldwide and is caused by the disruption of the equilibrium between osteoclastic bone resorption and osteoblastic bone formation. Sphingosine-1-phosphate (S1P) is a natural, bioactive sphingolipid that has been shown to play a major role in cardiovascular and immunological pathologies by regulating biological and cellular processes, including migration, differentiation, proliferation and survival. Recent studies also suggest a central role for S1P in bone diseases, including osteoporosis; however, the effects of S1P, particularly in bone metabolism, remain to be further elucidated. In this review, we summarize the available literature on the role of S1P in bone metabolism with a focus on osteoporosis. On the cellular level, S1P acts as an osteoclast-osteoblast coupling factor to promote osteoblast proliferation and bone formation. Moreover, the recruitment of osteoclast precursors to resorption sites is regulated by the interplay of S1P gradients and S1P receptor expression. From a clinical perspective, increasing evidence suggests that systemically elevated S1P blood levels may serve as an independent risk factor for osteoporosis-related fractures. Taken together, S1P signaling is a potential therapeutic target and may serve as a novel biomarker in patients with systemic bone disease.

A community-based coronavirus disease (COVID-19) active case-finding strategy using an antigen-detecting rapid diagnostic test (Ag-RDT) was implemented in the Democratic Republic of Congo (DRC) to enhance COVID-19 case detection. With this pilot community-based active case finding and response program that was designed as a clinical, prospective testing performance, and implementation study, we aimed to identify insights to improve community diagnosis and rapid response to COVID-19. This pilot study was modeled on the DRC's National COVID-19 Response Plan and the COVID-19 Ag-RDT screening algorithm defined by the World Health Organization (WHO), with case findings implemented in 259 health areas, 39 health zones, and 9 provinces. In each health area, a 7-member interdisciplinary field team tested the close contacts (ring strategy) and applied preventive and control measures to each confirmed case. The COVID-19 testing capacity increased from 0.3 tests per 10,000 inhabitants per week in the first wave to 0.4, 1.6, and 2.2 in the second, third, and fourth waves, respectively. From January to November 2021, this capacity increase contributed to an average of 10.5% of COVID-19 tests in the DRC, with 7,110 positive Ag-RDT results for 40,226 suspected cases and close contacts who were tested (53.6% female, median age: 37 years [interquartile range: 26.0-50.0)]. Overall, 79.7% (n = 32,071) of the participants were symptomatic and 7.6% (n = 3,073) had comorbidities. The Ag-RDT sensitivity and specificity were 55.5% and 99.0%, respectively, based on reverse transcription polymerase chain reaction analysis, and there was substantial agreement between the tests (k = 0.63). Despite its limited sensitivity, the Ag-RDT has improved COVID-19 testing capacity, enabling earlier detection, isolation, and treatment of COVID-19 cases. Our findings support the community testing of suspected cases and asymptomatic close contacts of confirmed cases to reduce disease spread and virus transmission.

Interconnectivity between neocortical areas is critical for sensory integration and sensorimotor transformations.sup.1-6. These functions are mediated by heterogeneous inter-areal cortical projection neurons (ICPN), which send axon branches across cortical areas as well as to subcortical targets.sup.7-9. Although ICPN are anatomically diverse.sup.10-14, they are molecularly homogeneous.sup.15, and how the diversity of their anatomical and functional features emerge during development remains largely unknown. Here we address this question by linking the connectome and transcriptome in developing single ICPN of the mouse neocortex using a combination of multiplexed analysis of projections by sequencing.sup.16,17 (MAPseq, to identify single-neuron axonal projections) and single-cell RNA sequencing (to identify corresponding gene expression). Focusing on neurons of the primary somatosensory cortex (S1), we reveal a protracted unfolding of the molecular and functional differentiation of motor cortex-projecting ([Formula omitted]) ICPN compared with secondary somatosensory cortex-projecting ([Formula omitted]) ICPN. We identify SOX11 as a temporally differentially expressed transcription factor in [Formula omitted] versus [Formula omitted] ICPN. Postnatal manipulation of SOX11 expression in S1 impaired sensorimotor connectivity and disrupted selective exploratory behaviours in mice. Together, our results reveal that within a single cortical area, different subtypes of ICPN have distinct postnatal paces of molecular differentiation, which are subsequently reflected in distinct circuit connectivities and functions. Dynamic differences in the expression levels of a largely generic set of genes, rather than fundamental differences in the identity of developmental genetic programs, may thus account for the emergence of intra-type diversity in cortical neurons. Combined analysis of the connectome and transcriptome in the mouse cortex indicates that dynamic differences in expression levels of largely generic sets of genes regulate differential targeting within neuronal subtypes., Author(s): Esther Klingler [sup.1] , Ugo Tomasello [sup.1] , Julien Prados [sup.2] , Justus M. Kebschull [sup.3] [sup.6] , Alessandro Contestabile [sup.1] , Gregorio L. Galiñanes [sup.1] , Sabine Fièvre [...]

Acquired resistance is inevitable in non–small cell lung cancers (NSCLCs) treated with osimertinib (OSI), and the mechanisms are not well defined. The MERTK ligand GAS6 promoted downstream oncogenic signaling in EGFR-mutated (EGFRMT) NSCLC cells treated with OSI, suggesting a role for MERTK activation in OSI resistance. Indeed, treatment with MRX-2843, a first-in-class MERTK kinase inhibitor, resensitized GAS6-treated NSCLC cells to OSI. Both GAS6 and EGF stimulated downstream PI3K/AKT and MAPK/ERK signaling in parental cells, but only GAS6 activated these pathways in OSI-resistant (OSIR) derivative cell lines. Functionally, OSIR cells were more sensitive to MRX-2843 than parental cells, suggesting acquired dependence on MERTK signaling. Furthermore, MERTK and/or its ligands were dramatically upregulated in EGFRMT tumors after treatment with OSI in both xenograft models and patient samples, consistent with induction of autocrine/paracrine MERTK activation. Moreover, treatment with MRX-2843 in combination with OSI, but not OSI alone, provided durable suppression of tumor growth in vivo, even after treatment was stopped. These data identify MERTK as a driver of bypass signaling in treatment-naive and EGFRMT-OSIR NSCLC cells and predict that MRX-2843 and OSI combination therapy will provide clinical benefit in patients with EGFRMT NSCLC.

In this issue honoring the contributions of Greg Lemke, the Earp and Graham lab teams discuss several threads in the discovery, action, signaling, and translational/clinical potential of MERTK, originally called c-mer, a member of the TYRO3, AXL, and MERTK (TAM) family of receptor tyrosine kinases. The 30-year history of the TAM RTK family began slowly as all three members were orphan RTKs without known ligands and/or functions when discovered by three distinct alternate molecular cloning strategies in the pre-genome sequencing era. The pace of understanding their physiologic and pathophysiologic roles has accelerated over the last decade. The activation of ligands bridging externalized phosphatidylserine (PtdSer) has placed these RTKs in a myriad of processes including neurodevelopment, cancer, and autoimmunity. The field is ripe for further advancement and this article hopefully sets the stage for further understanding and therapeutic intervention. Our review will focus on progress made through the collaborations of the Earp and Graham labs over the past 30 years. [ABSTRACT FROM AUTHOR]

Background: The World Health Organization issued interim guidelines on essential health system preparedness and response measures for the coronavirus disease 2019 (COVID-19) pandemic. The control of the pandemic requires healthcare system preparedness and response. Aim: This study aimed to evaluate frontline COVID-19 primary health care professionals’ (PHC-Ps) views on health system preparedness and response to the pandemic in the Mahalapye Health District (MHD). Setting: In March 2020, the Botswana Ministry of Health directed health districts to educate their health professionals about COVID-19. One hundred and seventy frontline PHC-Ps were trained in MHD; they evaluated the health system’s preparedness and response. Methods: This was a cross-sectional study that involved a self-administered questionnaire using the Integrated Disease Surveillance and Health System response guidelines. Results: The majority (72.5%) of participants felt unprepared to deal with the COVID-19 pandemic at their level. Most of the participants (70.7%) acknowledged that the health system response plan has been followed. About half of the participants attributed a low score regarding the health system’s preparedness (44.4%), its response (50.0%), and its overall performance (55.6%) to the COVID-19 pandemic. There was an association between participants’ age and work experience and their overall perceptions of preparedness and response (p = 0.009 and p = 0.005, respectively). Conclusion: More than half of the participants gave a low score to the MHD regarding the health system’s preparedness and response to the COVID-19 pandemic. Further studies are required to determine the causes of such attitudes and to be better prepared to respond effectively.

Introduction: HIV healthcare services for men who have sex with men (MSM) in Kenya have not been openly provided because of persistent stigma and lack of healthcare capacity within Kenya's decentralized health sector. Building on an evaluation of a developed online MSM sensitivity training programme offered to East and South African healthcare providers, this study assessed views and responses to strengthen HIV healthcare services for MSM in Kenya. Methods: The study was conducted between January and July 2017 in Kilifi County coastal Kenya. Seventeen policymakers participated in an in-depth interview and 59 stakeholders, who were purposively selected from three key groups (i.e. healthcare providers, implementing partners and members of MSM-led community-based organizations) took part in eight focus group discussions. Discussions aimed to understand gaps in service provision to MSM from different perspectives, to identify potential misconceptions, and to explore opportunities to improve MSM HIV healthcare services. Interviews and focus group discussions were recorded, transcribed verbatim and analysed using Braun and Clarke's thematic analysis. Results: Participants' responses revealed that all key groups navigated diverse challenges related to MSM HIV health services. Specific challenges included priority-setting by county government staff; preparedness of leadership and management on MSM HIV issues at the facility level; data reporting at the implementation level and advocacy for MSM health equity. Strong power inequities were observed between policy leadership, healthcare providers and MSM, with MSM feeling blamed for their sexua orientation. MSM agency, as expressed in their actions to access HIV services, was significantly constrained by county context, but can potentially be improved by political will, professional support and a human rights approach. Conclusions: To strengthen HIV healthcare for MSM within a decentralized Kenyan health system, a more responsive, multi-pronged strategy adaptable and relevant to MSM's healthcare needs is required. Continued engagement with policy leadership, collaboration with health facilities, and partnerships with different community stakeholders are critical to improve HIV healthcare services for MSM. Keywords: HIV healthcare services; MSM; Kenya; decentralization; health equity, 1 | INTRODUCTION Kenya has among the largest HIV epidemics in the world with an estimated 1.6 million people living with HIV, 46,000 new infections, and 25,000 AIDS-related deaths in [...]

Acquired resistance is inevitable in non-small cell lung cancers (NSCLCs) treated with osimertinib (OSI), and the mechanisms are not well defined. The MERTK ligand GAS6 promoted downstream oncogenic signaling in EGFR-mutated ([EGFR.sup.MT]) NSCLC cells treated with OSI, suggesting a role for MERTK activation in OSI resistance. Indeed, treatment with MRX-2843, a first-in-class MERTK kinase inhibitor, resensitized GAS6-treated NSCLC cells to OSI. Both GAS6 and EGF stimulated downstream PI3K/AKT and MAPK/ERK signaling in parental cells, but only GAS6 activated these pathways in OSI-resistant (OSIR) derivative cell lines. Functionally, OSIR cells were more sensitive to MRX-2843 than parental cells, suggesting acquired dependence on MERTK signaling. Furthermore, MERTK and/or its ligands were dramatically upregulated in [EGFR.sup.MT] tumors after treatment with OSI in both xenograft models and patient samples, consistent with induction of autocrine/paracrine MERTK activation. Moreover, treatment with MRX-2843 in combination with OSI, but not OSI alone, provided durable suppression of tumor growth in vivo, even after treatment was stopped. These data identify MERTK as a driver of bypass signaling in treatment-naive and [EGFR.sup.MT]-OSIR NSCLC cells and predict that MRX-2843 and OSI combination therapy will provide clinical benefit in patients with [EGFR.sup.MT] NSCLC., Introduction Lung cancer remains a global problem, causing more deaths in both men and women than any other cancer worldwide. Although the 5-year survival rate for lung cancer patients with [...]

Abstract Background The response rate on patient-reported outcome measurements (PROMs) necessary to adequately evaluate a treatment and improve patient care is unknown. Hospitals generally aim for the highest possible response rate without insight into the increase in costs involved. This study aimed to investigate which PROMs response rate is achievable in relation to the costs in an orthopaedic practice. Methods In an observational study, patients planned for orthopaedic surgery were asked to participate per surgical procedure (5769 surgical procedures at 5300 patients). Patient-reported outcomes (PROs) collection with a digital online automated PROMs collection system (minimal effort) was compared to a combined automated system and manual collection (maximal effort). Response rate was calculated preoperative and at two postoperative time points separately, and on all three time points together. Costs were calculated for the study period, per year and per surgical procedure. Calculations were executed for all surgical procedures and for three subgroups: knee arthroplasty, hip arthroplasty and anterior cruciate ligament reconstruction (ACLR). Results Using maximal effort the response rate increased for all surgical procedures compared to minimal effort; the preoperative response rate from 86% to 100% and the postoperative response rates from 55% to 83% (3 or 6 months) and 53% to 83% (12 months). Concerning the response at all three time points for all surgical procedures, minimal effort resulted in 44% response rate and increased to 76% with maximal effort. Lowest postoperative response rates were found in the ACLR group for both maximal and minimal effort. A costs difference of €5.55–€5.98 per surgical procedure between maximal and minimal effort was found. Conclusions A two times higher PROMs response rate for patients responding at all three time points (44% versus 76%) is achievable with maximal effort compared to the use of an automated PROMs collection system only. Manual collection adds a cost of €5.5–€6 per surgical procedure to automated PROMs collection alone. It is debatable if these additional costs are justifiable from a value-based health care perspective as the response rate for adequate evaluation of a treatment is still unknown.

Rotational Thromboelastometry (ROTEM) allows for the global assessment of hemostasis in whole blood samples. Preanalytical and analytical factors may influence test results, and data about the reliability and reproducibility of lyophilized ROTEM tests are scarce. Therefore, the objective of this study was to evaluate the influence of blood collection site on ROTEM S parameters and to assess intrarater and in-between device variability. A total of thirty, healthy, staff-owned dogs were included. Blood collection and ROTEM analysis were performed by trained staff according to a standardized protocol. Extrinsically activated (tissue factor; Ex-TEM S), with the addition of cytochalasin for platelet inhibition (Fib-TEM S), and intrinsically activated (In-TEM) analyses were performed. Analysis of our data showed significant variability for various Ex-TEM S and Fib-TEM S parameters from different collection sites and intrarater and in-between device measurements. We conclude that serial monitoring with ROTEM should be performed on the same device, with blood always taken from the same collection site using a standardized blood sampling technique. While In-TEM S, apart from maximum lysis, showed very stable and reliable results, we suggest interpreting especially clotting and clot formation parameters from Ex-TEM S and Fib-TEM S tests with caution and using duplicate measurements to detect outliers and to prevent initiation of incorrect therapies.