Influence of pH and temperature on the performance and microbial community during the production of medium-chain carboxylic acids using winery effluents as substrate.

Winery effluents containing high ethanol concentrations and diverse organic matter are ideal substrates for producing medium-chain carboxylic acids via fermentation and chain elongation. However, the process needs to be better understood. This study presents novel insights into the bioconversion mechanisms of medium-chain carboxylic acids by correlating fermentation and chain elongation kinetic profiles with the study of microbial communities at different pH (5 to 7) conditions and temperatures (30 to 40 °C). It was found that high productivities of MCCA were obtained using a native culture and winery effluents as a natural substrate. Minor pH variations significantly affected the metabolic pathway of the microorganisms for MCCA production. The maximal productivities of hexanoic (715 mg/L/d) and octanoic (350 mg/L/d) acids were found at pH 6 and 35 °C. Results evidence that the presence of Clostridium, Bacteroides, and Negativicutes promotes the high productions of MCCA. The formation of heptanoic acid was favor when Mogibacterium and Burkholderia were present.

Risk factors for pulmonary tuberculosis recurrence, relapse and reinfection: a systematic review and meta-analysis.

BACKGROUND: The rate of pulmonary tuberculosis (TB) recurrence is substantial. Identifying risk factors can support the development of prevention strategies. METHODS: We retrieved studies published between 1 January 1980 and 31 December 2022 that assessed factors associated with undifferentiated TB recurrence, relapse or reinfection. For factors reported in at least four studies, we performed random-effects meta-analysis to estimate a pooled relative risk (RR). We assessed heterogeneity, risk of publication bias and certainty of evidence. RESULTS: We included 85 studies in the review; 81 documented risk factors for undifferentiated recurrence, 17 for relapse and 10 for reinfection. The scope for meta-analyses was limited given the wide variety of factors studied, inconsistency in control for confounding and the fact that only few studies employed molecular genotyping. Factors that significantly contributed to moderately or strongly increased pooled risk and scored at least moderate certainty of evidence were: for undifferentiated recurrence, multidrug resistance (MDR) (RR 3.49; 95% CI 1.86 to 6.53) and fixed-dose combination TB drugs (RR 2.29; 95% CI 1.10 to 4.75) in the previous episode; for relapse, none; and for reinfection, HIV infection (RR 4.65; 95% CI 1.71 to 12.65). Low adherence to treatment increased the pooled risk of recurrence 3.3-fold (95% CI 2.37 to 4.62), but the certainty of evidence was weak. CONCLUSION: This review emphasises the need for standardising methods for TB recurrence research. Actively pursuing MDR prevention, facilitating retention in treatment and providing integrated care for patients with HIV could curb recurrence rates. The use of fixed-dose combinations of TB drugs under field conditions merits further attention. PROSPERO REGISTRATION NUMBER: CRD42018077867.

Wild bees of Chile: a database on taxonomy, sociality, and ecology.

Bees are a diverse group of insects that have tremendous importance as pollinators. In recent decades, there has been a global decline in bee populations because of land-use change, intensive agriculture, and climate change. Unfortunately, our knowledge of native bees' ecology is rather scarce, and such knowledge gaps are also a major threat to its conservation. In this sense, biological collections are a priceless natural history legacy and an information source for new research and decision making. Chile has a remarkable bee diversity, with 464 species currently known from Chile and a high incidence of endemism and a variety of habitats (including the Mediterranean biodiversity hotspot). The largest wild bee collection in Chile is held at the Pontificia Universidad Católica de Valparaíso (comprising a century of data). This collection has been recently included in GBIF. Here we present a database with 36,010 records, including information on sociality and ecology (including information on floral visitation range, the resource collected, and nesting substrates) for 160 out of the 167 bee species included (36% of the Chilean bee diversity, including 49 genera and five families). All records have the taxonomy resolved, and 83% of them have geographic coordinates, covering a latitudinal range between 18° S and 53° S from the continental and insular territories. This data set is released for noncommercial use only. Credits should be given to this paper (i.e., proper citation), and the products generated with this database should be shared under the same license terms (CC BY-NC-SA).

Recurrent TB: a systematic review and meta-analysis of the incidence rates and the proportions of relapses and reinfections.

BACKGROUND: A recurrent tuberculosis (TB) episode results from exogenous reinfection or relapse after cure. The use of genotyping allows the distinction between both. METHODS: We did a systematic review and meta-analysis, using four databases to search for studies in English, French and Spanish published between 1 January 1980 and 30 September 2020 that assessed recurrences after TB treatment success and/or differentiated relapses from reinfections using genotyping. We calculated person years of follow-up and performed random-effects model meta-analysis for estimating pooled recurrent TB incidence rates and proportions of relapses and reinfections. We performed subgroup analyses by clinical-epidemiological factors and by methodological study characteristics. FINDINGS: The pooled recurrent TB incidence rate was 2.26 per 100 person years at risk (95% CI 1.87 to 2.73; 145 studies). Heterogeneity was high (I2=98%). Stratified pooled recurrence rates increased from 1.47 (95% CI 0.87 to 2.46) to 4.10 (95% CI 2.67 to 6.28) per 100 person years for studies conducted in low versus high TB incidence settings. Background HIV prevalence, treatment drug regimen, sample size and duration of follow-up contributed too. The pooled proportion of relapses was 70% (95% CI 63% to 77%; I²=85%; 48 studies). Heterogeneity was determined by background TB incidence, as demonstrated by pooled proportions of 83% (95% CI 75% to 89%) versus 59% (95% CI 42% to 74%) relapse for studies from settings with low versus high TB incidence, respectively. INTERPRETATION: The risk of recurrent TB is substantial and relapse is consistently the most frequent form of recurrence. Notwithstanding, with increasing background TB incidence the proportion of reinfections increases and the predominance of relapses among recurrences decreases. PROSPERO REGISTRATION NUMBER: CRD42018077867.

A Social-Ecological Review of Cancer Disparities in Kentucky.

Cancer continuously ranks among the top 10 leading causes of death in the United States. The burden of cancer is particularly elevated in the Commonwealth of Kentucky and its 54-county Appalachian region, where cancer is the leading cause of death. Kentucky's high rates of cancer have been attributed to a wide range of socioeconomic, behavioral, environmental, and policy influences, resulting in numerous disparities. The present review specifically evaluates the burden of lung, colorectal, cervical, and head and neck cancers in Kentucky, along with resultant cancer control research and community outreach efforts conducted by the state's only National Cancer Institute-designated cancer center using an adapted version of McLeroy's Social-Ecological Model. Here, we categorize disparities and identify relevant intervention approaches based on their level of influence (ie, individual, community, and policy).

Outcome of Decolonization Therapy in a Hospital in Southern Puerto Rico.

OBJECTIVE: Methicillin resistant Staphylococcus aureus (MRSA) is a resistant bacteria responsible for hard-to-treat infections. To understand the primary impact of this infection in healthcare settings, a retrospective study was performed at a hospital in southern Puerto Rico. Our objectives were to classify the types of MRSA infection, identify factors associated with the infection, and evaluate the outcome of decolonization therapy after its having been implemented at the hospital. METHODS: Medical records of cases encompassing October 2009 through October 2011 were reviewed. A total of 761 MRSA-positive patients were identified and their infections classified as community-acquired MRSA (CA-MRSA), hospital-acquired MRSA (HA-MRSA), or healthcare-associated community-onset MRSA (HACO-MRSA). Basic demographics, reason for hospitalization, medical history, and culture sites, along with other information, were obtained for each case. SPSS v17 was used for statistical analysis. Fisher's exact test was used to measure the statistical significance of the crude OR, using the patients with CA-MRSA as the comparison group. HA-MRSA cases were compared before and after the intervention, using Epidat v4.0 to calculate the cumulative incidence of HA-MRSA before and after the implementation of decolonization therapy at the hospital. RESULTS: In our study, 5.0% of the patients were found to be infected with HA-MRSA, 72.8%, with CA-MRSA, and 22.2%, with HACO-MRSA. After the intervention, we found a decrease of 10.35% (p = 0.704) in HA-MRSA, of 2.6% (p = 0.791) in CA-MRSA, and of 7.0% in HACO-MRSA (p = 0.650). CONCLUSION: Our findings suggest that CA-MRSA could be responsible for the majority of the infections caused by MRSA within the hospital at which the study took place. Decolonization of MRSA is a useful tool in helping to control the spread of infection, although future studies are needed to confirm our study's findings.

Phenolic profiles of nectar and honey of Quillaja saponaria Mol. (Quillajaceae) as potential chemical markers.

Quillaja saponaria Mol. (Quillajaceae) is one of the most important melliferous species in Chile, mainly as a source of monofloral honey. Honey made by A. mellifera presents biological activity against pathogens and antioxidant capacity associated with the presence of phenolic compounds deriving from the nectar, as a result of bee honey foraging. The aim of this study was to identify and quantify the phenolic compounds from the floral nectar of Q. saponaria and the honey made in apiaries in the central zone, and compare the composition of the chromatographic profiles of nectar and honey to known phenolic compounds. The results obtained by HPLC-DAD (high-performance liquid chromatography with diode-array detection) showed a similar profile of phenolic compounds, in which gallic acid, myricetin, rutin, quercetin and naringenin were identified. The phenolic compounds detected could be used as a reference for future studies for determining potential chemical markers of this honey, complementing the present identification of honeys by determining their botanical origin. The identification of bioindicators of the floral origins for honey of this species could provide added value to honey commercialization by certifying the botanical origin of their chemical features and biological attributes.

Phenolic profiles of nectar and honey of Quillaja saponaria Mol. (Quillajaceae) as potential chemical markers

Quillaja saponaria Mol. (Quillajaceae) is one of the most important melliferous species in Chile, mainly as a source of monofloral honey. Honey made by A. mellifera presents biological activity against pathogens and antioxidant capacity associated with the presence of phenolic compounds deriving from the nectar, as a result of bee honey foraging. The aim of this study was to identify and quantify the phenolic compounds from the floral nectar of Q. saponaria and the honey made in apiaries in the central zone, and compare the composition of the chromatographic profiles of nectar and honey to known phenolic compounds. The results obtained by HPLC-DAD (high-performance liquid chromatography with diode-array detection) showed a similar profile of phenolic compounds, in which gallic acid, myricetin, rutin, quercetin and naringenin were identified. The phenolic compounds detected could be used as a reference for future studies for determining potential chemical markers of this honey, complementing the present identification of honeys by determining their botanical origin. The identification of bioindicators of the floral origins for honey of this species could provide added value to honey commercialization by certifying the botanical origin of their chemical features and biological attributes.