ACSM1 and ACSM3 regulate fatty acid metabolism to support prostate cancer growth and constrain ferroptosis.

Solid tumors are highly reliant on lipids for energy, growth, and survival. In prostate cancer, the activity of the androgen receptor (AR) is associated with reprogramming of lipid metabolic processes. Here, we identified acyl-CoA synthetase medium chain family members 1 and 3 (ACSM1 and ACSM3) as AR-regulated mediators of prostate cancer metabolism and growth. ACSM1 and ACSM3 were upregulated in prostate tumors compared to non-malignant tissues and other cancer types. Both enzymes enhanced proliferation and protected prostate cancer cells from death in vitro, while silencing ACSM3 led to reduced tumor growth in an orthotopic xenograft model. ACSM1 and ACSM3 were major regulators of the prostate cancer lipidome and enhanced energy production via fatty acid oxidation. Metabolic dysregulation caused by loss of ACSM1/3 led to mitochondrial oxidative stress, lipid peroxidation and cell death by ferroptosis. Conversely, elevated ACSM1/3 activity enabled prostate cancer cells to survive toxic levels of medium chain fatty acids and promoted resistance to ferroptosis-inducing drugs and AR antagonists. Collectively, this study reveals a tumor-promoting function for medium chain acyl-CoA synthetases and positions ACSM1 and ACSM3 as key players in prostate cancer progression and therapy resistance.

The overlap of accessory virulence factors and multidrug resistance among clinical and surveillance Klebsiella pneumoniae isolates from a neonatal intensive care unit in Nepal: a single-centre experience in a resource-limited setting.

BACKGROUND: There is a lack of data on the characteristics of overlap between acquired antimicrobial resistance and virulence factors in Klebsiella pneumoniae in high-risk settings, especially with the inclusion of surveillance isolates along with the clinical. We investigated K. pneumoniae isolates, from a neonatal intensive care unit (NICU) in Nepal, for the presence of both accessory virulence factors and acquired antimicrobial resistance. METHODS: Thirty-eight clinical and nineteen surveillance K. pneumoniae isolates obtained between January 2017 and August 2022 in the NICU of Siddhi Memorial Hospital, Bhaktapur, Nepal were investigated with antimicrobial susceptibility testing, PCR-based detection of ß-lactamases and virulence factors, and genetic similarity by ERIC-PCR. RESULTS: K. pneumoniae was found positive in 37/85 (43.5%) blood culture-positive neonatal bloodstream infections, 34/954 (3.6%) patient surveillance cultures, and 15/451 (3.3%) environmental surveillance samples. Among 57 isolates analyzed in this study, we detected multidrug resistance in 37/57 (64.9%), which was combined with at least one accessory virulence factor in 21/37 (56.8%). This overlap was mostly among ß-lactamase producing isolates with accessory mechanisms of iron acquisition. These isolates displayed heterogenous ERIC-PCR patterns suggesting genetic diversity. CONCLUSIONS: The clinical significance of this overlap between acquired antimicrobial resistance and accessory virulence genes in K. pneumoniae needs further investigation. Better resource allocation is necessary to strengthen infection prevention and control interventions in resource-limited settings.

The causes of bacterial bloodstream infections and antimicrobial resistance patterns in children attending a secondary care hospital in Bhaktapur, Nepal, 2017-2022: a retrospective study.

Objectives: Data on antimicrobial resistance (AMR) among children in Nepal are limited. Here we have characterized the causes of bacterial bloodstream infections (BSIs), antimicrobial resistance patterns and the mechanisms of ß-lactamase production in Enterobacterales among children attending outpatient and inpatient departments of a secondary care paediatric hospital in Nepal. Methods: We retrospectively collected demographic and clinical data of culture-proven bacterial BSIs between January 2017 and December 2022 among children <18 years attending a 50-bedded paediatric hospital. Stored isolates were subcultured for antimicrobial susceptibility testing against commonly used antimicrobials. Enterobacterales displaying non-susceptibility to ß-lactams were phenotypically and genotypically investigated for ESBLs, plasmid-mediated AmpC (pAmpC) ß-lactamases and carbapenemases. Results: A total of 377 significant bacteria were isolated from 27 366 blood cultures. Among 91 neonates with a BSI, Klebsiella pneumoniae (n = 39, 42.4%), Pseudomonas aeruginosa (n = 15, 16.3%) and Acinetobacter baumannii complex (n = 13, 14.1%) were most common. In the non-neonates, 275/285 (96.5%) infections were community-acquired including Staphylococcus aureus (n = 89, 32.4%), Salmonella Typhi (n = 54, 19.6%) and Streptococcus pneumoniae (n = 32, 11.6%). Among the 98 S. aureus, 29 (29.6%) were methicillin-resistant Staphylococcus aureus. K. pneumoniae and Escherichia coli demonstrated non-susceptibility to extended-spectrum cephalosporins and carbapenems in both community and hospital-acquired cases. For E. coli and K. pneumoniae, blaCTX-M (45/46), blaEBC (7/10) and blaOXA-48 (5/6) were common among their respective groups. Conclusions: We determined significant levels of AMR among children attending a secondary care paediatric hospital with BSI in Nepal. Nationwide surveillance and implementation of antimicrobial stewardship policies are needed to combat the challenge imposed by AMR.

Characterization of Transferrable Mechanisms of Quinolone Resistance (TMQR) among Quinolone-resistant Escherichia coli and Klebsiella pneumoniae causing Urinary Tract Infection in Nepalese Children.

BACKGROUND: Transferrable mechanisms of quinolone resistance (TMQR) can lead to fluoroquinolone non-susceptibility in addition to chromosomal mechanisms. Some evidence suggests that fluoroquinolone resistance is increasing among the pediatric population. We sought to determine the occurrence of TMQR genes among quinolone-resistant E. coli and K. pneumoniae causing urinary tract infections among Nepalese outpatient children (< 18 years) and identify molecular characteristics of TMQR-harboring isolates. METHODS: We performed antimicrobial susceptibility testing, phenotypic extended-spectrum ß-lactamase (ESBL) and modified carbapenem inactivation method tests, and investigated the presence of six TMQR genes (qnrA, qnrB, qnrS, aac(6')-Ib-cr, oqxAB, qepA), three ESBL genes (blaCTX-M, blaTEM, blaSHV), and five carbapenemase genes (blaNDM, blaOXA-48, blaKPC, blaIMP, blaVIM). The quinolone resistance-determining region (QRDR) of gyrA and parC were sequenced for 35 TMQR-positive isolates. RESULTS: A total of 74/147 (50.3%) isolates were TMQR positive by multiplex PCR [aac(6')-Ib-cr in 48 (32.7%), qnrB in 23 (15.7%), qnrS in 18 (12.3%), qnrA in 1 (0.7%), and oqxAB in 1 (0.7%) isolate]. The median ciprofloxacin minimum inhibitory concentration of TMQR-positive isolates (64 µg/mL) was two-fold higher than those without TMQR (32 µg/mL) (p = 0.004). Ser-83→Leu and Asp-87→Asn in GyrA and Ser-80→Ile in ParC were the most common QRDR mutations (23 of 35). In addition, there was a statistically significant association between TMQR and two ß-lactamase genes; blaCTX-M (p = 0.037) and blaTEM (p = 0.000). CONCLUSION: This study suggests a high prevalence of TMQR among the quinolone-resistant E. coli and K. pneumoniae isolates causing urinary tract infection in children in this area of Nepal and an association with the carriage of ESBL gene. This is a challenge for the management of urinary infections in children. Comprehensive prospective surveillance of antimicrobial resistance in these common pathogens will be necessary to devise strategies to mitigate the emergence of further resistance.

Characteristics of Pregnant Women and Risk Factors of Their Newborn for Admission to a Neonatal Intensive Care Unit in Nepal.

BACKGROUND: Nepal has progressed gradually in reducing under-5 mortality and neonatal mortality; however, they are still high at 30.8 and 19.8 per 1000 live births, respectively. Neonatal mortality constituted about 64% of the under-5 mortality in 2019, higher than the global average of 47%. METHODS: This is a prospective study among pregnant women and their newborn babies in Siddhi Memorial Hospital, Bhaktapur, Nepal, from October 2017 to April 2018. Demographic and clinical data, high vaginal swabs of pregnant mothers, and umbilical cord blood were collected. High vaginal swabs were cultured, and umbilical cord blood samples were cultured and tested for inflammatory markers. After discharge to home, neonates were followed for 28 days of life by weekly phone calls. RESULTS: Total number of pregnant mothers enrolled was 151. The median age was 26 years (IQR: 18-40), and the proportion of adolescent mothers was 4.7%. Half of the deliveries were done by the caesarian section, and 8.6% had gestational age <37 weeks. High vaginal swab cultures were positive in 8.2% of the samples (n=135), and Escherichia coli was the most common bacteria. Out of 153 newborn babies (2 were twins), 8 (5.2%) were admitted to the neonatal intensive care unit. The proportion of low birth weight was 13%, and it was independently associated with neonatal intensive care unit admission (adjusted OR=9.4, 95%CI 1.8-50.1; P value= 0.009). CONCLUSIONS: Adolescent pregnancies and Low Birth Weight babies were commonly observed. Both of these issues need to be addressed by effective measures that would improve the current situation of maternal and child health in Nepal.

Emergence of Multi-Drug Resistance and Its Association With Uncommon Serotypes of Streptococcus agalactiae Isolated From Non-neonatal Patients in Thailand.

Group B streptococcus (GBS) or Streptococcus agalactiae is an opportunistic pathogen that causes serious illness in newborns, pregnant women, and adults. However, insufficient detection methods and disease prevention programs have contributed to an increase in the incidence and fatality rates associated with this pathogen in non-neonatal patients. This study aimed to investigate factors of the observed increased incidence by investigation of serotype distribution, virulence factors, and antimicrobial susceptibility patterns from invasive GBS disease among non-neonatal patients in Thailand. During 2017-2018, a total of 109 S. agalactiae isolates were collected from non-pregnant patients. There were 62 males and 47 females, with an average age of 63.5 years (range: 20 - 96). Serotypes were determined by latex agglutination assay and multiplex polymerase chain reaction (PCR)-based assay. Among those isolates, seven virulence genes (rib, bca, pavA, lmb, scpB, cylE, and cfb) were detected by PCR amplification, and were determined for their susceptibility to 20 antimicrobial agents using a SensititreTM Streptococcus species STP6F AST plate. Among the study isolates, serotype III was predominant (52.3%), followed by serotype V and serotype VI (13.8% for each), serotype Ib (11.9%), and other serotypes (8.2%). Of the seven virulence genes, pavA was found in 67.0%. Except for one, there were no significant differences in virulence genes between serotype III and non-serotype III. Study isolates showed an overall rate of non-susceptibility to penicillin, the first-line antibiotic, of only 0.9%, whereas the resistance rates measured in tetracycline, clindamycin, azithromycin, and erythromycin were 41.3, 22.0, 22.0, and 22.0%, respectively. Strains that were resistant to all four of those drugs were significantly associated with non-serotype III (p < 0.001). Using multi-locus sequence typing (MLST), 40.0% of the four-drug-resistant isolates belonged to serotype VI/ST1, followed by serotype Ib/ST1 (35.0%). Cluster analysis with global GBS isolates suggested that the multiple drug-resistant isolates to be strongly associated with the clonal complex (CC) 1 (p < 0.001). Compared to the 2014 study of 210 invasive GBS isolates conducted in 12 tertiary hospitals in Thailand, the proportion of serotype III has dramatically dropped from nearly 90% to about 50%. This suggests that resistances to the second-line antibiotics for GBS might be the selective pressure causing the high prevalence of non-serotype III isolates.

Correction to: Changes in nutritional status of children who lived in temporary shelters in Bhaktapur municipality after the 2015 Nepal earthquake.

[This corrects the article DOI: 10.1186/s41182-020-00225-8.].

Changes in nutritional status of children who lived in temporary shelters in Bhaktapur municipality after the 2015 Nepal earthquake.

BACKGROUND: The nutritional status of children may deteriorate after natural disasters such as earthquakes. A 7.8 Richter scale earthquake struck Nepal in 2015 that affected 1.1 million children. Children whose homes were destroyed and had to live in temporary shelters were at risk of malnutrition. With the support of Nagasaki University School of Tropical Medicine and Global Health (TMGH) and Siddhi Memorial Hospital (SMH), we conducted a nutritional survey of under-5 children living in temporary shelters in Bhaktapur Municipality in 2015 immediately after the earthquake and a follow-up survey in 2017. RESULTS: We found 591 under-5 children living in 22 temporary shelters in 2015. A total of 285 children were followed up and re-assessed in 2017. In a paired analysis (n = 285), the prevalence of underweight children increased from 10.9% in 2015 to 14.0% in 2017 (P < 0.001), stunting increased from 26.7 to 31.9% (P = 0.07), and wasting decreased from 4.2 to 2.5% (P = 0.19). CONCLUSIONS: Children who lived in temporary shelters after the 2015 Nepal earthquake might be at increased risk of a deterioration in nutritional status.

Prevalence of vitamin D deficiency in pregnant women and their babies in Bhaktapur, Nepal.

BACKGROUND: Vitamin D deficiency has been observed worldwide in pregnant women and their newborns. Maternal vitamin D deficiency can lead to deficiency in their newborn baby and has been linked with various complications during pregnancy and delivery. There is risk of premature delivery and it is associated with high neonatal mortality. METHODS: Seventy-nine pregnant women who were admitted to the Siddhi Memorial Hospital for delivery and their newborn babies were enrolled in the study. Maternal blood samples were taken before delivery while umbilical cord blood samples of their babies were taken after delivery. Serum vitamin D level and calcium level were assessed by fluorescence immunoassay using Ichromax vitamin D kit and endpoint method, respectively in the Siddhi Memorial Hospital laboratory. RESULTS: Mean +/- SD serum vitamin D and calcium levels in pregnant mother before delivery were 14.6 +/- 8.5 ng/ml and 8.0 +/- 0.5 mg/dl, respectively, and in the cord blood were 25.7 +/- 11.2 ng/ml and 8.6 +/- 0.9 mg/dl, respectively. Eighty-one percent of the mothers and 35.8% of their babies were found to have vitamin D deficiency. Although 97.5% of the pregnant women were taking calcium supplementation, serum calcium was found lower than the normal reference value in 67% of the pregnant women and 64.2% of their babies. There were a linear relationship between the maternal and baby's serum vitamin D (P < 0.001) and calcium (P < 0.001) levels. CONCLUSION: There is high prevalence of vitamin D and calcium deficiency in pregnant mothers and newborn babies in Bhaktapur, Nepal. Pregnant women need to be supplemented with adequate amounts of these nutrients.

Pattern of thyroid dysfunction in patients with metabolic syndrome and its relationship with components of metabolic syndrome.

BACKGROUND: Thyroid dysfunction (TD) and metabolic syndrome (MetS) are known risk factors for atherosclerotic cardiovascular disease (ASCVD). TD is risk factor for ASCVD mediated by the effects of thyroid hormones on lipid metabolism and blood pressure hence the components of MetS. It is possible that coexistence of these two disease entities and unrecognized TD in patients with MetS might substantially increase ASCVD risk. Moreover, little is known about the relationship between TD and the components of MetS. Thus, the purpose of this study was to evaluate the pattern of TD in patients with MetS and its relationship with components of the MetS. METHODS: A total of 358 previously diagnosed patients with MetS were recruited in the study. The thyroid function test parameters were measured to classify TD at Dhulikhel Hospital-Kathmandu University Hospital, Dhulikhel, Nepal. Statistical analyses were performed using SPSS version 16.0 to evaluate pattern and relationship. RESULTS: The overall prevalence of TD in patients with MetS was 31.84% with high prevalence of subclinical hypothyroidism (29.32%). We found no evidence of a relationship between TD and components of MetS, although there was significant difference in waist circumference between four groups of TD. CONCLUSION: Patients with MetS had subclinical hypothyroidism greatly. Although there was no evidence of any relationship between thyroid status and all components of MetS, TD should be taken into account when evaluating and treating patients with MetS to reduce the impending risk.