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Male sterility in the domestic fowl (Gallus domesticus) after 1-(2-chloroethyl)-3-(4-methylcyclohexyl)-1-nitroso-trans-urea (NSC-95441) treatment of chicks.

Of 11 male baby chicks treated twice with 3 mg of 1-(2-chloroethyl)-3-(4-methylcyclohexyl)-1-nitroso-trans-urea (once on the day of hatching and once on the day after), 9 showed absolute lack of spermatogenesis and 2 showed severe inhibition when examined at the age of 6 months. Plasma testosterone level was not altered, however, and histologic examination revealed well-organized testicular interstitial tissue with an abundance of Leydig's cells. In the lining of the seminiferous tubules only Sertoli's cells were present. The weight of the testes from treated animals was only about 10% of control weight. These findings emphasized the possibility that the nitrosoureas cause severe damage to the reproductive system in man.

Animals

[Absolute teratozoospermia in a family. Irregular microcephalic spermatozoa without acrosome].

Two brothers have spermiograms with a similar pattern: absolute teratozoospermia with round-headed spermatozoa. The familial trait only has been previously one time in the literature. The spermatozoa show several abnormalities in the head. They lack acrosome and postacrosomal sheath. The nuclei are small and the chromatin is distributed in small groups. The nuclear envelope has abundant pores and is loosely attached to the chromatin. All the nuclei have brown inclusions, refringent when they are observed under the light microscope, vesicular and laminar under the electron microscope. Other abnormalities less frequently observed are: irregularities in the mitochondrial sheath, loss of parallelism of the dense fibres and duplication and angulation of the sperm tail. The hormonal assays and the biochemical tests are normal in both patients.

Acrosome

A guide to the recent literature on aspergillosis as caused by Aspergillus fumigatus, a fungus frequently found in self-heating organic matter.

Spores of Aspergillus fumigatus have been found to be abundantly present in the outdoor air at a site where large scale experimental composting of sewage sludge is in progress at Beltsville, Maryland. The health significance of this finding, for that site and for others in the future, is still only incompletely understood. Further studies are in progress to characterize absolute concentrations of the spores of the fungus in air at the site, spore dispersal by air from composting operations, and background environmental spore levels in air. The present paper contains a list of references to papers on health effects of A. fumigatus, many published in the past ten years, along with a review of the same designed to assist the reader in finding information on particular aspects of the subject in the literature. It is intended primarily as an aid to individuals interested in sludge composting and wishing to attain an insight into the A. fumigatus-composting situation, but it may also interest others concerned with other substrates which become moldy at 40--50 C. A. fumigatus has been found in great numbers in naturally and artificially heated environments such as decaying leaves, compost heaps, solar heated sloughs, cooling canals for nuclear power generators, silos, grain storage bins, boiler rooms, detritus around steam turbines and sauna baths. The evident practical merits of sludge composting have been described elsewhere; the information presented here has its main significance in respect to requirements for choice of locations for composting sites and to process and design criteria.

Animals

[Mechanism of the cardioprotective effect of triamterene in the rat heart. Myocardial protection via elevation of extracellular K+ and Mg++ concentrations].

1. 2,4,7-Triamino-6-phenyl-pteridine (triamterene) protects the rat heart against isoproterenol-induced myocardial lesions: Whilst cardiotoxic doses of isoproterenol produce deleterious myocardial Ca overload, simultaneous admistration of triamterene diminishes myocardial Ca incorporation considerably. 2. As to the mechanism of action, triamterene increases the plasma contents of K and Mg by inhibiting renal excretion. Accordingly, oral administration of K and Mg salts, leading to a similar rise in the K and Mg concentrations of the plasma, also prevents abundant myocardial Ca incorporation. 3. Cardioprotection by triamterene can, in fact, be simply explained by its action on the plasma K and (particularly) Mg levels. This conclusion is drawn from a quantitative comparison of the inhibitory effects of triamterene (40 mg/kg s.c.) with those of KCl or MgCl2 (10 mMol/kg p.o.) on the isoproterenol-induced increase in myocardial 45Ca uptake and absolute Ca concentration. 4. Isoproterenol induced cardiomyopathy of the rat, an experimental model of non-coronarogenic myocardial lesions, has hitherto been successfully prevented with the use of Ca-antagonists (verapamil, D 600, prenylamine, fendiline). These compounds reduce Ca influx by restricting the Ca conductivity of the myocardial sarcolemma membrane ("slow channel"). The action of triamterene, on the other hand, is based on a totally different cardioprotective principle, namely competitive inhibition of intracellular myocardial Ca accumulation via an increase in K and Mg supply. In the future treatment of cardiomyopathy it seems rather promising to try a combination of both a Ca-antagonist and triamterene, thus applying two different therapeutic principles simultaneously.

Animals

Comprehensive quantitative modeling of translation efficiency in a genome-reduced bacterium.

Translation efficiency has been mainly studied by ribosome profiling, which only provides an incomplete picture of translation kinetics. Here, we integrated the absolute quantifications of tRNAs, mRNAs, RNA half-lives, proteins, and protein half-lives with ribosome densities and derived the initiation and elongation rates for 475 genes (67% of all genes), 73 with high precision, in the bacterium Mycoplasma pneumoniae (Mpn). We found that, although the initiation rate varied over 160-fold among genes, most of the known factors had little impact on translation efficiency. Local codon elongation rates could not be fully explained by the adaptation to tRNA abundances, which varied over 100-fold among tRNA isoacceptors. We provide a comprehensive quantitative view of translation efficiency, which suggests the existence of unidentified mechanisms of translational regulation in Mpn.

RNA, Transfer

Microbial Interactions with Protein Intake and Preterm Infant Body Composition: Secondary Analysis of a Randomized Trial.

BACKGROUND: Enteral protein supplementation improves preterm infant growth and may impact body composition and the gut microbiota. OBJECTIVES: This study aimed to identify the effects of additional enteral protein supplementation on the gut microbiota and microbial and clinical drivers of body composition. METHODS: Secondary analysis of a masked randomized trial of additional enteral protein vs. standard fortification in preterm infants born at 25 to 28 weeks of gestation (NCT03586102) was conducted. Stool samples at weeks 4 and 8 underwent 16S rRNA sequencing; functional potential was predicted by Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt2). Body composition was measured by air-displacement plethysmography at 36 wk postmenstrual age (PMA). Least absolute shrinkage and selection operator (LASSO) regression with multivariable linear regression identified body composition predictors. RESULTS: Among 46 infants, gestational age (P = 0.16) and sex (P = 0.55) did not differ between groups. The protein group had higher week 4 Shannon diversity than standard fortification (median 1.2 vs. 0.87, P = 0.049). Week 4 Shannon diversity was positively correlated with fat-free mass z-score at 36 wk PMA (r2 = 0.34, P = 0.02). Adjusting for covariates, the protein group had higher Peptoniphilus (&#x3b2; = 1.6, Padj = 0.10) and lower Vibrio centered log-ratio abundance (&#x3b2; = -0.98, Padj = 0.10); 62 predicted metabolic pathways were lower in the protein group (false discovery rate < 0.20). In combined LASSO models, Bacillus abundance at week 4 was the strongest predictor of fat-free mass z-score (&#x3b2; = -0.17, P < 0.001; R2 = 0.80) and fat mass z-score (&#x3b2; = -0.31, P < 0.001; R2 = 0.66). CONCLUSIONS: Additional protein supplementation is associated with fat-free mass z-score and alterations to the gut microbiota. Clinical variables and microbial variables are key predictors of body composition, suggesting that nutrition, clinical factors, and the gut microbiota jointly contribute to body composition in extremely preterm infants. This study was registered at clinicaltrials.gov as NCT03586102 https://clinicaltrials.gov/study/NCT03586102 (registered in March 2020).

Humans

Metabolic-cell-death gene trio predicts survival and cuproptosis sensitivity in colorectal cancer.

BACKGROUND: Metabolic cell death (MCD) modulates colorectal cancer (CRC) progression, yet its prognostic value remains unexplored. We aimed to build an MCD-centred gene signature for outcome prediction and precision therapy. METHODS: Transcriptomes of 1,174 CRC patients were integrated. Weighted gene co-expression network analysis, differential expressions and least absolute shrinkage and selection operator (LASSO) + random survival forest were successively applied to derive a three-gene (CDKN2A/MPC1/AHCY) risk model. Functional, immune-infiltration, drug-sensitivity and genomic analyses were performed, followed by validation in fresh clinical specimens and cell lines. RESULTS: Integrative metabolic-death transcriptomics identified CDKN2A, MPC1 and AHCY as the hub drivers of CRC. Their three-gene signature robustly stratified patients into high- and low-risk subsets [3-year area under the curve (AUC) 0.83-0.85, P<0.001]. High-risk tumors were enriched for extracellular matrix (ECM)-receptor-interaction pathways, displayed abundant myeloid-derived suppressor cell (MDSC) infiltration and were more vulnerable to AZD8186, AZ960 and JAK inhibitors. Guided by these in-silico findings, we functionally confirmed that CDKN2A silencing markedly repressed proliferation, invasion and migration of SW480/HCT116 cells and potentiated cuproptosis via up-regulation of lipoylated DLAT/DLST and CTR1. CONCLUSIONS: We report the first MCD-derived prognostic platform for CRC that simultaneously predicts survival and therapeutic response. Targeting CDKN2A-enhanced cuproptosis represents a promising metabolic-precision strategy for high-risk patients.

Colorectal cancer (CRC)

ZBTB16-associated NK cell alterations reveal shared immunometabolic signatures linking primary Sj&#xf6;gren's syndrome and type 1 diabetes mellitus.

BACKGROUND: Primary Sj&#xf6;gren's syndrome (pSS) and type 1 diabetes mellitus (T1DM) share immune-inflammatory features, yet conserved pathogenic signatures linking these autoimmune disorders remain incompletely understood. The present research sought to uncover common molecular markers and dissect the underlying immune-metabolic cross-talk underlying pSS and T1DM. METHODS: Gene expression profiles of patients with pSS and T1DM were retrieved from the Gene Expression Omnibus database, normalized, and corrected for batch effects prior to downstream analyses. Overlapping potential biomarkers were screened by integrating differential expression analysis, weighted gene co-expression network analysis and least absolute shrinkage and selection operator regression. Functional enrichment based on Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases was implemented to interpret gene biological properties, and a protein-protein interaction network was further established afterwards. Diagnostic performance was evaluated using receiver operating characteristic analysis. Experimental validation was conducted in non-obese diabetic (NOD) mice using quantitative PCR, immunohistochemistry, and flow cytometry. The CIBERSORT algorithm was adopted to quantify immune cell infiltration levels. RESULTS: ZBTB16 was identified as a shared hub biomarker in both pSS and T1DM and exhibited favorable diagnostic performance. Experimental validation confirmed significantly reduced ZBTB16 expression in peripheral blood mononuclear cells, salivary gland tissues, and pancreatic tissues of NOD mice. Gene Set Enrichment Analysis indicated that ZBTB16-associated signatures were enriched in mitochondrial-related processes, neuroactive ligand-receptor interactions, and ribosome-related pathways. Immune infiltration analysis revealed that resting natural killer (NK) cells were positively correlated with ZBTB16 expression in both diseases. Flow cytometric analysis further confirmed a reduced proportion of resting NK cells in peripheral blood of NOD mice, consistent with the CIBERSORT-based prediction. CONCLUSION: This study identifies ZBTB16 as a shared biomarker linking pSS and T1DM. Reduced resting NK-cell abundance was consistently observed in both computational and experimental analyses, and bioinformatic correlation analysis suggested a positive association with ZBTB16 expression. These findings provide evidence for shared molecular and immunological signatures underlying the two autoimmune disorders and support further investigation of the biological role and diagnostic value of ZBTB16 in pSS and T1DM.

Sjogren's Syndrome

Estimating Rhizobial Fitness During Legume Symbiosis: Enriching Viable Undifferentiated Bacteria from Root Nodules.

Advances in understanding the evolutionary ecology of the rhizobia-legume mutualism have been constrained by methodological limitations in efficiently measuring relative strain frequencies alongside measurements of absolute population sizes of rhizobia living in nodules. To examine strain competition in natural and agricultural ecosystems that harbor multiple strains of rhizobia, an increasing number of manipulative and observational studies have recently begun to examine dozens or hundreds of strains simultaneously. Assessing the competitive fitness of multiple strains in legume nodules requires, first, processing pools of dozens to hundreds of nodules to overcome the stochasticity of nodule formation; second, focusing on the reproductively viable rhizobial population, since this trait represents rhizobia's reproductive success in nodules and is pivotal for evolutionary interpretations. Our approach has been optimized in the Medicago truncatula-Sinorhizobium meliloti system, where rhizobia induce the formation of indeterminate nodules that harbor two subpopulations: terminally-differentiated bacteroids and undifferentiated rhizobia that retain reproductive viability. This protocol has also been used for other legumes with terminally-differentiated bacteroids, such as pea and vetch, as well as for those with non-terminally differentiated bacteroids, such as soybean and cowpeas. The protocol we present enables rapid and reproducible homogenization of pools containing hundreds of nodules using a tissue homogenizer. We also enrich for undifferentiated rhizobia using two centrifugation steps: first, a low-speed centrifugation to deplete nodule debris and large, endoreduplicated, terminally-differentiated bacteroids, followed by a high-speed centrifugation to pellet the remaining undifferentiated rhizobia. The pellet can later be used for DNA extraction, followed by whole-genome or amplicon sequencing, and then downstream analysis to estimate strain fitness. Finally, we include an optional&#xa0;step for a reliable, reproducible system for nodule imaging, which is especially useful for quantifying nodule abundance and studying morphological variation. &#x200b;.

Symbiosis