High regeneration may not contribute to the forest's carbon storage: a case study in the mangrove forest of Rajang-Belawai-Paloh delta, Sarawak.

The alarming rate of the mangrove ecosystem loss poses a threat of losing valuable carbon sinks. This study was conducted to (i) determine the growth structure in different vegetation types and (ii) compare the aboveground biomass (AGB) and carbon storage in different vegetation types. The study was conducted at four vegetation types within the Rajang-Belawai-Paloh delta i.e., Matured Bakau-Berus Forest (MBBF), Bakau-Nipah Forest (BNF), Regenerating Forests (Debris pile) [RF-D], and Regenerating Forests (Machinery track) [RF-M]. Inventory plots (20 m × 20 m) are systematically located along the main waterways and smaller rivers/streams. Trees (≥ 5 cm diameter-at-breast height [DBH]), seedlings (< 2-cm stem diameter), and saplings (2-4.9-cm stem diameter) were measured. The trend of total trees per hectare is found to be decreasing across the least disturbed vegetation (MBBF) to the most disturbed vegetation (RF-M). The trends of total seedlings and saplings per hectare are found to be going upwards from the least disturbed vegetation to the most disturbed vegetation. Kruskal-Wallis H-test showed that there is a significant difference in the AGB and carbon storage between different vegetation types, χ2(2) = 43.98, p = 0.00 with the highest mean rank AGB and carbon storage in BNF (612.20 t/ha) and lowest in RF-M (287.85 t/ha). It can be concluded that although the most disturbed vegetations have higher regeneration, it may not contribute to the forest's carbon storage The naturally regenerated seedlings may not grow beyond the sapling stage unless sustainable forest management is conducted to ensure survivability and growth.

Klebsiella pneumoniae clinical isolates with features of both multidrug-resistance and hypervirulence have unexpectedly low virulence.

Klebsiella pneumoniae has been classified into two types, classical K. pneumoniae (cKP) and hypervirulent K. pneumoniae (hvKP). cKP isolates are highly diverse and important causes of nosocomial infections; they include globally disseminated antibiotic-resistant clones. hvKP isolates are sensitive to most antibiotics but are highly virulent, causing community-acquired infections in healthy individuals. The virulence phenotype of hvKP is associated with pathogenicity loci responsible for siderophore and hypermucoid capsule production. Recently, convergent strains of K. pneumoniae, which possess features of both cKP and hvKP, have emerged and are cause of much concern. Here, we screen the genomes of 2,608 multidrug-resistant K. pneumoniae isolates from the United States and identify 47 convergent isolates. We perform phenotypic and genomic characterization of 12 representative isolates. These 12 convergent isolates contain a variety of antimicrobial resistance plasmids and virulence plasmids. Most convergent isolates contain aerobactin biosynthesis genes and produce more siderophores than cKP isolates but not more capsule. Unexpectedly, only 1 of the 12 tested convergent isolates has a level of virulence consistent with hvKP isolates in a murine pneumonia model. These findings suggest that additional studies should be performed to clarify whether convergent strains are indeed more virulent than cKP in mouse and human infections.

Unusual Mycobacterium marinum Infection in a Heart Transplant Recipient: A Case Report.

Mycobacterium marinum (M. marinum) is a species of nontuberculous mycobacteria that is a rare cause of disease in humans and is usually associated with aquatic exposures. Symptoms manifest, on average, three weeks after exposure, although cases with longer incubation periods have been reported in the literature. Herein, we describe an unusual case presentation of an M. marinum infection in the left upper extremity of a heart transplant recipient. The case is notable for its prolonged incubation period and for being the first documented case of M. marinum infection in a heart transplant recipient. We hypothesize that, given the patient's immunosuppressive medication regimen in the post-transplant period, this case could represent a reactivation phenomenon of a latent infection.

Screening of Human Gut Bacterial Culture Collection Identifies Species That Biotransform Quercetin into Metabolites with Anticancer Properties.

We previously demonstrated that flavonoid metabolites inhibit cancer cell proliferation through both CDK-dependent and -independent mechanisms. The existing evidence suggests that gut microbiota is capable of flavonoid biotransformation to generate bioactive metabolites including 2,4,6-trihydroxybenzoic acid (2,4,6-THBA), 3,4-dihydroxybenzoic acid (3,4-DHBA), 3,4,5-trihyroxybenzoic acid (3,4,5-THBA) and 3,4-dihydroxyphenylacetic acid (DOPAC). In this study, we screened 94 human gut bacterial species for their ability to biotransform flavonoid quercetin into different metabolites. We demonstrated that five of these species were able to degrade quercetin including Bacillus glycinifermentans, Flavonifractor plautii, Bacteroides eggerthii, Olsenella scatoligenes and Eubacterium eligens. Additional studies showed that B. glycinifermentans could generate 2,4,6-THBA and 3,4-DHBA from quercetin while F. plautii generates DOPAC. In addition to the differences in the metabolites produced, we also observed that the kinetics of quercetin degradation was different between B. glycinifermentans and F. plautii, suggesting that the pathways of degradation are likely different between these strains. Similar to the antiproliferative effects of 2,4,6-THBA and 3,4-DHBA demonstrated previously, DOPAC also inhibited colony formation ex vivo in the HCT-116 colon cancer cell line. Consistent with this, the bacterial culture supernatant of F. plautii also inhibited colony formation in this cell line. Thus, as F. plautii and B. glycinifermentans generate metabolites possessing antiproliferative activity, we suggest that these strains have the potential to be developed into probiotics to improve human gut health.

Pilot Study of a Farm-to-Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) Intervention Promoting Vegetable Consumption.

BACKGROUND: Vegetable intake is below recommended levels among adults served by the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). OBJECTIVE: The aim of this study was to determine whether a novel, theory-driven, farm-to-WIC intervention to promote vegetable intake showed promise of being successful and is therefore appropriate for efficacy testing. DESIGN: From June 2019 to January 2020, the intervention was piloted in three WIC agency sites (one randomized to the intervention study group and two to the control group) selected based on similarity in size and the demographics of participants served. PARTICIPANTS/SETTING: Recruited between June 3, 2019 and August 1, 2019, participants were 297 primarily Hispanic adults served by a large WIC agency located in a densely populated urban area in New Jersey (160 were enrolled at the intervention site and 137 at control sites). INTERVENTION: The intervention combined behaviorally focused instruction and handouts with the introduction of a WIC-based farmers' market, field trips to an area farmers' market, telephone coaching and support before and after trips, and recipe demonstrations and tastings. MAIN OUTCOME MEASURES: The primary outcomes were vegetable intake (measured objectively using dermal carotenoids as a biomarker of intake and via self-report) and the redemption of vouchers provided through the WIC Farmers' Market Nutrition Program (FMNP) for fruit and vegetable purchases at farmers' markets (objectively assessed using data provided by WIC). STATISTICAL ANALYSES PERFORMED: Between-group differences in vegetable intake were examined at mid- and post-intervention (3 and 6 months post-baseline, respectively) with linear mixed-effects models adjusted for baseline vegetable intake and covariates. Logistic regression analysis was used to relate FMNP voucher redemption to study group and covariates. RESULTS: At mid-intervention, objectively measured vegetable intake was higher among participants in the control group as compared with the intervention group; self-reported intake did not differ by group. Post-intervention, objectively measured and self-reported vegetable intake were higher among participants in the intervention group as compared with the control group. Receipt of the intervention was associated with a greater likelihood of FMNP voucher redemption. Voucher redemption rates were 87% in the intervention group and 28% in the control group (odds ratio = 17.39, 95% confidence interval [8.64, 35.02]). CONCLUSIONS: Meaningful associations found between the intervention, vegetable intake, and FMNP voucher redemption suggest that the program is appropriate for efficacy testing.

Facile Synthesis and Metabolic Incorporation of m-DAP Bioisosteres Into Cell Walls of Live Bacteria.

Bacterial cell walls contain peptidoglycan (PG), a scaffold that provides proper rigidity to resist lysis from internal osmotic pressure and a barrier to protect cells against external stressors. It consists of repeating sugar units with a linkage to a stem peptide that becomes cross-linked by cell wall transpeptidases (TP). While synthetic PG fragments containing l-lysine in the third position on the stem peptide are easier to access, those with meso-diaminopimelic acid (m-DAP) pose a severe synthetic challenge. Herein, we describe a solid phase synthetic scheme based on widely available building blocks to assemble meso-cystine (m-CYT), which mimics key structural features of m-DAP. To demonstrate proper mimicry of m-DAP, cell wall probes were synthesized with m-CYT in place of m-DAP and evaluated for their metabolic processing in live bacterial cells. We found that m-CYT-based cell wall probes were properly processed by TPs in various bacterial species that endogenously contain m-DAP in their PG. Additionally, we have used hybrid quantum mechanical/molecular mechanical (QM/MM) and molecular dynamics (MD) simulations to explore the influence of m-DAP analogs on the PG cross-linking. The results showed that the cross-linking mechanism of transpeptidases occurred through a concerted process. We anticipate that this strategy, which is based on the use of inexpensive and commercially available building blocks, can be widely adopted to provide greater accessibility of PG mimics for m-DAP containing organisms.

Population Genomic Analysis of Mycoplasma bovis Elucidates Geographical Variations and Genes associated with Host-Types.

: Among more than twenty species belonging to the class Mollecutes, Mycoplasma bovis is the most common cause of bovine mycoplasmosis in North America and Europe. Bovine mycoplasmosis causes significant economic loss in the cattle industry. The number of M. bovis positive herds recently has increased in North America and Europe. Since antibiotic treatment is ineffective and no efficient vaccine is available, M. bovis induced mycoplasmosis is primarily controlled by herd management measures such as the restriction of moving infected animals out of the herds and culling of infected or shedders of M. bovis. To better understand the population structure and genomic factors that may contribute to its transmission, we sequenced 147 M. bovis strains isolated from four different countries viz. USA (n = 121), Canada (n = 22), Israel (n = 3) and Lithuania (n = 1). All except two of the isolates (KRB1 and KRB8) were isolated from two host types i.e., bovine (n = 75) and bison (n = 70). We performed a large-scale comparative analysis of M. bovis genomes by integrating 103 publicly available genomes and our dataset (250 total genomes). Whole genome single nucleotide polymorphism (SNP) based phylogeny using M. agalactiae as an outgroup revealed that M. bovis population structure is composed of five different clades. USA isolates showed a high degree of genomic divergence in comparison to the Australian isolates. Based on host of origin, all the isolates in clade IV was of bovine origin, whereas majority of the isolates in clades III and V was of bison origin. Our comparative genome analysis also revealed that M. bovis has an open pangenome with a large breadth of unexplored diversity of genes. The function based analysis of autogenous vaccine candidates (n = 10) included in this study revealed that their functional diversity does not span the genomic diversity observed in all five clades identified in this study. Our study also found that M. bovis genome harbors a large number of IS elements and their number increases significantly (p = 7.8x10-6) as the genome size increases. Collectively, the genome data and the whole genome-based population analysis in this study may help to develop better understanding of M. bovis induced mycoplasmosis in cattle.

Structure-Guided Design of a Fluorescent Probe for the Visualization of FtsZ in Clinically Important Gram-Positive and Gram-Negative Bacterial Pathogens.

Addressing the growing problem of antibiotic resistance requires the development of new drugs with novel antibacterial targets. FtsZ has been identified as an appealing new target for antibacterial agents. Here, we describe the structure-guided design of a new fluorescent probe (BOFP) in which a BODIPY fluorophore has been conjugated to an oxazole-benzamide FtsZ inhibitor. Crystallographic studies have enabled us to identify the optimal position for tethering the fluorophore that facilitates the high-affinity FtsZ binding of BOFP. Fluorescence anisotropy studies demonstrate that BOFP binds the FtsZ proteins from the Gram-positive pathogens Staphylococcus aureus, Enterococcus faecalis, Enterococcus faecium, Streptococcus pyogenes, Streptococcus agalactiae, and Streptococcus pneumoniae with Kd values of 0.6-4.6 µM. Significantly, BOFP binds the FtsZ proteins from the Gram-negative pathogens Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii with an even higher affinity (Kd = 0.2-0.8 µM). Fluorescence microscopy studies reveal that BOFP can effectively label FtsZ in all the above Gram-positive and Gram-negative pathogens. In addition, BOFP is effective at monitoring the impact of non-fluorescent inhibitors on FtsZ localization in these target pathogens. Viewed as a whole, our results highlight the utility of BOFP as a powerful tool for identifying new broad-spectrum FtsZ inhibitors and understanding their mechanisms of action.

L,D-Transpeptidase Specific Probe Reveals Spatial Activity of Peptidoglycan Cross-Linking.

Peptidoglycan (PG) is a cross-linked, meshlike scaffold endowed with the strength to withstand the internal pressure of bacteria. Bacteria are known to heavily remodel their peptidoglycan stem peptides, yet little is known about the physiological impact of these chemical variations on peptidoglycan cross-linking. Furthermore, there are limited tools to study these structural variations, which can also have important implications on cell wall integrity and host immunity. Cross-linking of peptide chains within PG is an essential process, and its disruption thereof underpins the potency of several classes of antibiotics. Two primary cross-linking modes have been identified that are carried out by D,D-transpeptidases and L,D-transpeptidases (Ldts). The nascent PG from each enzymatic class is structurally unique, which results in different cross-linking configurations. Recent advances in PG cellular probes have been powerful in advancing the understanding of D,D-transpeptidation by Penicillin Binding Proteins (PBPs). In contrast, no cellular probes have been previously described to directly interrogate Ldt function in live cells. Herein, we describe a new class of Ldt-specific probes composed of structural analogs of nascent PG, which are metabolically incorporated into the PG scaffold by Ldts. With a panel of tetrapeptide PG stem mimics, we demonstrated that subtle modifications such as amidation of iso-Glu can control PG cross-linking. Ldt probes were applied to quantify and track the localization of Ldt activity in Enterococcus faecium, Mycobacterium smegmatis, and Mycobacterium tuberculosis. These results confirm that our Ldt probes are specific and suggest that the primary sequence of the stem peptide can control Ldt cross-linking levels. We anticipate that unraveling the interplay between Ldts and other cross-linking modalities may reveal the organization of the PG structure in relation to the spatial localization of cross-linking machineries.

Linked cycles of oxidative decarboxylation of glyoxylate as protometabolic analogs of the citric acid cycle.

The development of metabolic approaches towards understanding the origins of life, which have focused mainly on the citric acid (TCA) cycle, have languished-primarily due to a lack of experimentally demonstrable and sustainable cycle(s) of reactions. We show here the existence of a protometabolic analog of the TCA involving two linked cycles, which convert glyoxylate into CO2 and produce aspartic acid in the presence of ammonia. The reactions proceed from either pyruvate, oxaloacetate or malonate in the presence of glyoxylate as the carbon source and hydrogen peroxide as the oxidant under neutral aqueous conditions and at mild temperatures. The reaction pathway demonstrates turnover under controlled conditions. These results indicate that simpler versions of metabolic cycles could have emerged under potential prebiotic conditions, laying the foundation for the appearance of more sophisticated metabolic pathways once control by (polymeric) catalysts became available.

2-18F-fluoro-2-deoxyglucose positron emission tomography in delirium.

Delirium is a common, serious, yet poorly understood syndrome. Growing evidence suggests cerebral metabolism is fundamentally disturbed; however, it has not been investigated using 2-18F-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) in delirium. This prospective study thus explored FDG PET patterns of cerebral glucose metabolism in older inpatients with delirium. A particular emphasis was on the posterior cingulate cortex (PCC), a key region for attention, which is a central feature of delirium. Delirium scans were compared with post-delirium scans using visual analysis and semi-quantitative analysis with NeuroQ; 13 participants (8 female, median 84 y) were scanned during delirium, and 6 scanned again after resolution. On visual analysis, cortical hypometabolism was evident in all participants during delirium (13/13), and improved with delirium resolution (6/6). Using NeuroQ, glucose metabolism was higher post-delirium in the whole brain and bilateral PCC compared to during delirium ( p < 0.05). Greater metabolism in both PCCs correlated with better performance on a neuropsychological test of attention, the WAIS-IV Digit Span Test forwards, and with shorter delirium duration. This research found widespread, reversible cortical hypometabolism during delirium and PCC hypometabolism was associated with inattention during delirium.

Genetic Analysis and Species Specific Amplification of the Artemisinin Resistance-Associated Kelch Propeller Domain in P. falciparum and P. vivax.

Plasmodium falciparum resistance to artemisinin has emerged in the Greater Mekong Subregion and now poses a threat to malaria control and prevention. Recent work has identified mutations in the kelch propeller domain of the P. falciparum K13 gene to be associated artemisinin resistance as defined by delayed parasite clearance and ex vivo ring stage survival assays. Species specific primers for the two most prevalent human malaria species, P. falciparum and P. vivax, were designed and tested on multiple parasite isolates including human, rodent, and non- humans primate Plasmodium species. The new protocol described here using the species specific primers only amplified their respective species, P. falciparum and P. vivax, and did not cross react with any of the other human malaria Plasmodium species. We provide an improved species specific PCR and sequencing protocol that could be effectively used in areas where both P. falciparum and P. vivax are circulating. To design this improved protocol, the kelch gene was analyzed and compared among different species of Plasmodium. The kelch propeller domain was found to be highly conserved across the mammalian Plasmodium species.

Desarrollo de jalea de yacón de reducido valor calórico: caracterización físico-química, microbiológica y sensorial / Development of a low calorie yacon jam: physico chemical, microbiological and sensory characterization

This study aimed to evaluate the physical-chemical, microbiological and sensory characteristics of four formulations of yacon jams. The following characteristics were analyzed: chemical composition, soluble solids, pH, microbiological presence of total coliforms and salmonella at 45 °C, and presence of fungi and yeasts. The yacon jams exhibited high moisture content (> 62%) as well as high concentrations of carbohydrates (> 28%) and total dietary fiber (2.5%), mainly fructooligosaccharides (> 0.9%). The average energy value was 124.6 kcal/100 g. The average pH was 3.8 and the soluble solids measured 27.6 °Brix. All yacon jams complied with standard microbiological requirements and received high acceptance scores, especially the yacon jam and yacon jam with cinnamon. Yacon jam products may offer an excellent alternative to more common jams due to their lower concentrations of simple sugar, lower calorie value, increased presence of dietary fibers, and desirable sensory characteristics.

Este estudio tuvo como objetivo evaluar las características físico-químicas, microbiológicas y sensoriales de cuatro formulaciones de mermeladas de yacón. Las características analizadas fueron: composición química, contenido de sólidos solubles, pH, presencia microbiológica de coliformes totales, coliformes y salmonella a 45 °C, y la presencia de hongos y levaduras. Los atascos de yacón mostraron alto contenido de humedad (> 62%), así como altas concentraciones de hidratos de carbono (> 28%) y fibra dietética total (2, 5%), principalmente fructooligosacáridos (> 0, 9%). El valor energético promedio fue de 124, 6 kcal/100g. El pH promedio fue de 3, 8 y los sólidos solubles mide 27, 6 ° Brix. Todas las mermeladas de yacón cumplido con los requisitos microbiológicos estándar y recibió altos puntajes de aceptación, en especial la mermelada de yacón y mermelada de yacón con canela. Productos de mermelada de yacón pueden ofrecer una excelente alternativa a los atascos más comunes debido a sus concentraciones más bajas de azúcar simple, un valor más bajo de calorías, el aumento de la presencia de fibras dietéticas y las características sensoriales deseadas.

In vivo protein quality of new sorghum genotypes for human consumption.

The in vivo protein qualities were evaluated in flours from raw sorghum grains (RF) and flours from sorghum grains subjected to heat treatment in an oven (HTF) from the hybrids BRS 305, BRS 309 and BRS 310, developed by the Brazilian Agricultural Research Corporation (Embrapa). There were no differences in feed efficiency ratios among experimental groups. Heat-treated flour from BRS 309 and BRS 310 genotypes had higher protein efficiency ratios and net protein ratio values; however, they did not differ from those of flour from raw grain of BRS 310 genotype. Effects of heat treatment were observed in the BRS 309 genotype. Heat treatment did not affect true digestibility observed for the RF and HTF of the three genotypes. Lysine was the first limiting amino acid of the three sorghum genotypes. The HTF BRS 305 showed the lowest protein digestibility-corrected amino acid score value. Heat treatment improved the protein quality of genotype BRS 309; however, no differences were observed among the other genotypes.

Perioperative seizures in patients with a history of a seizure disorder.

BACKGROUND: The occurrence of perioperative seizures in patients with a preexisting seizure disorder is unclear. There are several factors unique to the perioperative period that may increase a patient's risk of perioperative seizures, including medications administered, timing of medication administration, missed doses of antiepileptic medications, and sleep deprivation. We designed this retrospective chart review to evaluate the frequency of perioperative seizures in patients with a preexisting seizure disorder. METHODS: We retrospectively reviewed the medical records of all patients with a documented history of a seizure disorder who received an anesthetic between January 1, 2002 and December 31, 2007. Patients excluded from this study include those who had an outpatient procedure or intracranial procedure, ASA classification of V, pregnant women, and patients younger than 2 years of age. The first hospital admission of at least 24 hours during which an anesthetic was provided was identified for each patient. Patient demographics, character of the seizure disorder, details of the surgical procedure, and clinically apparent seizure activity in the perioperative period (within 3 days after the anesthetic) were recorded. RESULTS: During the 6-year study period, 641 patients with a documented seizure disorder were admitted for at least 24 hours after an anesthetic. Twenty-two patients experienced perioperative seizure activity for an overall frequency of 3.4%(95% confidence interval, 2.2%-5.2%). The frequency of preoperative seizures (P < 0.001) and the timing of the most recent seizure (P < 0.001) were both found to be significantly related to the likelihood of experiencing a perioperative seizure. As the number of antiepileptic medications increased, so did the frequency of perioperative seizures (P < 0.001). Neither the type of surgery nor the type of anesthetic (general anesthesia, regional anesthesia, or monitored anesthesia care) affected the frequency of perioperative seizures in this patient population. CONCLUSIONS: We conclude that the majority of perioperative seizures in patients with a preexisting seizure disorder are likely related to the patient's underlying condition. The frequency of seizures is not influenced by the type of anesthesia or procedure. Because patients with frequent seizures at baseline are likely to experience a seizure in the perioperative period, it is essential to be prepared to treat seizure activity regardless of the surgical procedure or anesthetic technique.

An exploration of pre-sleep cognitive activity in insomnia: imagery and verbal thought.

OVERVIEW: Patients with insomnia commonly report that unpleasant intrusive thoughts and images prevent them falling asleep. Previous research has documented the topics people with insomnia think about during the pre-sleep period, but has not yet distinguished between different types of cognitive activity. Given that research relating to the anxiety disorders suggests that different types of cognitive activity, in particular images and verbal worry, are functionally independent, the present study aimed to provide a detailed phenomenological investigation of imagery and verbal thought in insomnia. DESIGN AND METHOD: A semi-structured interview, designed to assess the content and management of pre-sleep images and verbal thought, was administered to individuals with sleep-onset insomnia (N = 34) and good sleepers (N = 38) immediately following an afternoon nap. During the nap, heart rate and sleep-onset latency were measured objectively. RESULTS: The insomnia group was more likely than the good sleeper group to report negative images than positive images. The start, direction and stopping of pre-sleep images was rated as less controllable than pre-sleep verbal thoughts. CONCLUSION: Participants disengaged more from images compared with verbal thoughts, and the insomnia patients reported feeling less calm and relaxed at the end of the salient verbal thought compared with the good sleepers.

The differential functions of imagery and verbal thought in insomnia.

Individuals with insomnia were exposed to a stressor (speech threat) prior to getting into bed and were instructed to think about the speech and its implications in either images (Image group, n = 14) or verbal thought (Verbal group, n = 17). Participants completed questionnaires about speech anxiety, arousal, and sense of resolution. Measures were taken of subjective (sleep diary estimates) and objective (actigraphy) sleep-onset latency. In the short term, the Image group reported more distress and arousal relative to those in the Verbal group. In the longer term, the Image group estimated that they fell asleep more quickly and, the following morning, reported less anxiety and more comfort about giving the speech compared with the Verbal group.