Citrate-buffered Yamanaka medium allows to produce high-yield bacterial nanocellulose in static culture using Komagataeibacter strains isolated from apple cider vinegar.

Bacterial nanocellulose (BNC) is a sustainable, renewable, and eco-friendly nanomaterial, which has gained great attentions in both academic and industrial fields. Two bacterial nanocellulose-producing strains (CVV and CVN) were isolated from apple vinegar sources, presenting high 16S rRNA gene sequence similarities (96%-98%) with Komagataeibacter species. The biofilm was characterized by scanning electron microscopy (SEM), revealing the presence of rod-shaped bacteria intricately embedded in the polymeric matrix composed of nanofibers of bacterial nanocellulose. FTIR spectrum and XRD pattern additionally confirmed the characteristic chemical structure associated with this material. The yields and productivities achieved during 10 days of fermentation were compared with Komagataeibacter xylinus ATCC 53524, resulting in low levels of BNC production. However, a remarkable increase in the BNC yield was achieved for CVV (690% increase) and CVN (750% increase) strains at day 6 of the fermentation upon adding 22 mM citrate buffer into the medium. This effect is mainly attributed to the buffering capacity of the modified Yakamana medium, which allowed to maintain pH close to 4.0 until day 6, though in combination with additional factors including stimulation of the gluconeogenesis pathway and citrate assimilation as a carbon source. In addition, the productivities determined for both isolated strains (0.850 and 0.917 g L-1 d-1) compare favorably to previous works, supporting current efforts to improve fermentation performance in static cultures and the feasibility of scaling-up BNC production in these systems.

Long-term use of clomiphene in male macroprolactinomas with persistent hypogonadism.

BACKGROUND: Men with macroprolactinoma can present persistent hypogonadism despite normoprolactinemia achieved with clinical and/or neurosurgical treatment. Usually, testosterone replacement therapy is indicated. Nevertheless, although off-label, clomiphene citrate (CC), a selective estrogen receptor modulator, has also been used, mainly when fertility is an issue. The aim of this study is to evaluate the effectiveness of CC in recovering the gonadal axis in men with macroprolactinoma, with or without hyperprolactinemia, and evaluate its safety as a long-term therapy. METHODS: This is a retrospective study including 10 men with macroprolactinoma on cabergoline treatment and persistent hypogonadism. All patients received initially 50 mg/d of CC. RESULTS: The median age at diagnosis of prolactinomas was 34 (range, 26-60) years old. All patients were treated with cabergoline at a median maximum dose of 2 (1-7) mg/week, with a median time of treatment of 8.5 (2-15) years. Prolactin was still above the normal range when CC was introduced only in two patients. The mean duration of CC therapy was 3.2 (±2.8) years. Prolactin levels maintained stable (p = 0.252) and testosterone increased (p = 0.027) significantly on CC therapy. Tumor size remained stable. Eight patients (80%) maintained testosterone above 300 ng/dL and were classified as responders. Three responders succeeded in using a lower dose of CC and one of them completed withdrawal CC and maintained eugonadism. There were no side effects or safety concerns reported. CONCLUSION: CC should be seen as a safe treatment option for men with macroprolactinoma and persistent hypogonadism.

Anticoagulation in renal replacement therapies: Why heparin should be abandoned in critical ill patients?

Extracorporeal circuits used in renal replacement therapy (RRT) can develop thrombosis, leading to downtimes and reduced therapy efficiency. To prevent this, anticoagulation is used, but the optimal anticoagulant has not yet been identified. Heparin is the most widely used anticoagulant in RRT, but it has limitations, such as unpredictable pharmacokinetics, nonspecific binding to plasma proteins and cells, and the possibility of suboptimal anticoagulation or bleeding complications, specifically in critically ill patients with acute renal failure who are already at high risk of bleeding. Citrate anticoagulation is a better alternative, being considered a standard for continuous renal replacement therapy, since it is associated with a lower risk of bleeding complications and better efficacy, even in patients with acute renal failure or liver disease. The aim of this article is to provide an updated review of the different strategies of anticoagulation in renal replacement therapies that can be implemented in critical scenarios, focusing on the advantages and disadvantages of each one and the beneficial aspects of using citrate over heparin in critical ill patients.

Quality indicators in prolonged hemodialysis with regional citrate anticoagulation with the genius system: retrospective cohort of critical patients with acute kidney injury.

BACKGROUND: Prolonged hemodialysis (HD) is performed from 6 to 12 h and can last up to 24 h. To prevent system clotting some studies suggest that Regional Citrate Anticoagulation (RCA) use reduces bleeding rates relative to systemic heparin. However, there may be difficulties in the patient's clinical management and completing the prescribed HD with Genius system using RCA. OBJECTIVE: To analyze safety Quality Indicators (IQs) and follow up on prolonged HD with 4% sodium citrate solution in a Genius® hybrid system. METHODS: This is a retrospective cohort conducted in an intensive care unit. RESULTS: 53 random sessions of prolonged HD with 4% sodium citrate solution of critically ill patients with AKI assessed. Evaluated safety indicators were dysnatremia and metabolic alkalosis, observed in 15% and 9.4% of the sessions, respectively. Indicators of effectiveness were system clotting which occurred in 17.3%, and the minimum completion of the prescribed HD time, which was 75.5%. CONCLUSION: The assessment of the indicators showed that the use of RCA with a 4% sodium citrate solution in prolonged HD with the Genius system in critically ill patients with AKI can be performed in a simple, safe, and effective way.

Statistical Improvement of rGILCC 1 and rPOXA 1B Laccases Activity Assay Conditions Supported by Molecular Dynamics.

Laccases (E.C. 1.10.3.2) are glycoproteins widely distributed in nature. Their structural conformation includes three copper sites in their catalytic center, which are responsible for facilitating substrate oxidation, leading to the generation of H2O instead of H2O2. The measurement of laccase activity (UL-1) results may vary depending on the type of laccase, buffer, redox mediators, and substrates employed. The aim was to select the best conditions for rGILCC 1 and rPOXA 1B laccases activity assay. After sequential statistical assays, the molecular dynamics proved to support this process, and we aimed to accumulate valuable insights into the potential application of these enzymes for the degradation of novel substrates with negative environmental implications. Citrate buffer treatment T2 (CB T2) (pH 3.0 ± 0.2; λ420nm, 2 mM ABTS) had the most favorable results, with 7.315 ± 0.131 UL-1 for rGILCC 1 and 5291.665 ± 45.83 UL-1 for rPOXA 1B. The use of citrate buffer increased the enzyme affinity for ABTS since lower Km values occurred for both enzymes (1.49 × 10-2 mM for rGILCC 1 and 3.72 × 10-2 mM for rPOXA 1B) compared to those obtained in acetate buffer (5.36 × 10-2 mM for rGILCC 1 and 1.72 mM for rPOXA 1B). The molecular dynamics of GILCC 1-ABTS and POXA 1B-ABTS showed stable behavior, with root mean square deviation (RMSD) values not exceeding 2.0 Å. Enzyme activities (rGILCC 1 and rPOXA 1B) and 3D model-ABTS interactions (GILCC 1-ABTS and POXA 1B-ABTS) were under the strong influence of pH, wavelength, ions, and ABTS concentration, supported by computational studies identifying the stabilizing residues and interactions. Integration of the experimental and computational approaches yielded a comprehensive understanding of enzyme-substrate interactions, offering potential applications in environmental substrate treatments.

Potential of Cheese-Associated Lactic Acid Bacteria to Metabolize Citrate and Produce Organic Acids and Acetoin.

Lactic acid bacteria (LAB) are pivotal in shaping the technological, sensory, and safety aspects of dairy products. The evaluation of proteolytic activity, citrate utilization, milk pH reduction, and the production of organic compounds, acetoin, and diacetyl by cheese associated LAB strains was carried out, followed by Principal Component Analysis (PCA). Citrate utilization was observed in all Leuconostoc (Le.) mesenteroides, Le. citreum, Lactococcus (Lc.) lactis, Lc. garvieae, and Limosilactobacillus (Lm.) fermentum strains, and in some Lacticaseibacillus (Lact.) casei strains. Most strains exhibited proteolytic activity, reduced pH, and generated organic compounds. Multivariate PCA revealed Le. mesenteroides as a prolific producer of acetic, lactic, formic, and pyruvic acids and acetoin at 30 °C. Enterococcus sp. was distinguished from Lact. casei based on acetic, formic, and pyruvic acid production, while Lact. casei primarily produced lactic acid at 37 °C. At 42 °C, Lactobacillus (L.) helveticus and some L. delbrueckii subsp. bulgaricus strains excelled in acetoin production, whereas L. delbrueckii subsp. bulgaricus and Streptococcus (S.) thermophilus strains primarily produced lactic acid. Lm. fermentum stood out with its production of acetic, formic, and pyruvic acids. Overall, cheese-associated LAB strains exhibited diverse metabolic capabilities which contribute to desirable aroma, flavor, and safety of dairy products.

Effect of Clomiphene Citrate on the Ultrastructure of Testis in Albino Rats

SUMMARY: The aim of the present work was to study the closer effect of clomiphene citrate on the ultrastructure of the testis of adult albino rats to provide a basis for optimizing this drug in the treatment of male infertility. The testes were removed from both groups under anesthesia and then prepared for examination by light using hematoxylin and eosin stains and a transmission electron microscope. Semithin sections were cut into 1 µm thick sections, stained with toluidine blue, and examined by light microscopy for a survey. The desired areas were placed in the center, and other areas were trimmed. Primary spermatocytes showed marked nuclear changes (pyknosis), and their nuclear membranes were ill-defined and disrupted. The cytoplasm showed widespread degeneration of mitochondria and lysosomes and focal degeneration of the rough endoplasmic reticulum compared with the control group. The spermatids were pale, and the two phases of spermatogenesis were distinctly identifiable in the control group but were confused in the treated group. Some spermatids had interrupted nuclear membranes, also containing degenerated mitochondria, focal fragmentation of rough endoplasmic reticulum, and free ribosomes. Spermatozoa in the treated group appeared deformed compared to the control, where they had deformed head caps. Leydig cells of the treated group have an irregularly shaped nucleus, with focal chromatin aggregation and peripheral chromatin condensation on the inner surface of the nuclear membrane. The observations of the present work indicate a possible causal relationship between testicular affection and ingestion of clomiphene citrate, which can be avoided by close medical observations using ultrasonography, semen analysis, or testicular biopsy to detect early malignant changes. Furthermore, the drug should not be used for more than three to six cycles and should be stopped for at least three cycles before reuse. When clomiphene citrate is ineffective in the treatment of male infertility, human menopausal gonadotropin (hMG) administration is typically selected. However, high-dose hMG therapy is associated with a variety of adverse effects. In this work, we report the success of a modified clomiphene citrate regimen in increasing sperm count without any hazards to the testicular tissue.

El objetivo del trabajo fue estudiar el efecto del citrato de clomifeno sobre la estructura de los testículos de la rata albina adulta, con la finalidad de determinar la mejor manera de utilizar este fármaco en el tratamiento de la infertilidad masculina. Los testículos se extrajeron bajo anestesia y para su análisis a través de microscopio de luz se tiñeron con HE. Además, las muestras fueron preparadas para su examen con microscopía electrónica de transmisión. Por otra parte, se cortaron secciones semifinas de 1 µm de espesor, se tiñeron con azul de toluidina y se examinaron mediante microscopía óptica. Los espermatocitos primarios mostraron cambios nucleares marcados (picnosis) y sus membranas nucleares estaban mal definidas y alteradas. En el grupo experimental las células presentaban el citoplasma con degeneración generalizada de las mitocondrias y de los lisosomas y una degeneración focal del retículo endoplásmico rugoso en comparación con el grupo control. Las espermátidas estaban pálidas y las dos fases de la espermatogénesis eran claramente identificables en el grupo control, pero se confundían en el grupo tratado. Algunas espermátidas tenían membranas nucleares interrumpidas, y también contenían mitocondrias degeneradas, fragmentación focal del retículo endoplásmico rugoso y ribosomas libres. Los espermatozoides del grupo tratado se presentaban deformados en comparación con el control. Las células de Leydig del grupo tratado presentaban un núcleo de forma irregular, con agregación focal de cromatina y condensación de cromatina periférica en la superficie interna de la membrana nuclear. Las observaciones del presente trabajo indican una posible relación causal entre la afección testicular y la ingestión de citrato de clomifeno, que puede evitarse mediante observaciones médicas minuciosas a través de ecografía, análisis de semen o biopsia testicular para detectar cambios malignos tempranos. Además, el medicamento no debiera ser usado durante más de tres a seis ciclos y debe suspenderse durante al menos tres ciclos antes de volver a usarlo. Cuando el citrato de clomifeno es ineficaz en el tratamiento de la infertilidad masculina, normalmente se selecciona la administración de gonadotropina menopáusica humana (hMG). Sin embargo, la terapia con hMG en dosis altas se asocia con una variedad de efectos adversos. En este trabajo, informamos el éxito de un régimen modificado con citrato de clomifeno para aumentar el recuento de espermatozoides sin riesgo para el tejido testicular.

White epaxial muscle aerobic and anaerobic potential and muscle fiber structure in surface and cave morphotypes of the Mexican cavefish (Astyanax mexicanus).

Proper muscle function and muscle fiber structures that match the environmental demands of organisms are imperative to their success in any ecosystem. The Mexican cavefish, Astyanax mexicanus, has two morphotypes: an obligate cave-dwelling form that lives in thermally insulated caves and an O2 poor environment, and a surface form that lives in a more thermally variable, but O2 rich river environment. As environment can determine physiological adaptations, it is of interest to compare the aerobic and anaerobic metabolic profiles of white muscle metabolism in both morphotypes of this species, as well as their muscle structures. Here, we used white muscle of both morphotypes of the Mexican cavefish to determine citrate synthase (CS) activity as a measure of aerobic potential, and lactate concentration as a measure of anaerobic potential at three different chronic acclimation temperatures (14°C, 25°C, and 31°C). By examining aerobic and anaerobic potential in both morphs, we sought to link environmental thermal flexibility to muscle metabolism. We found that the surface morphotype had higher CS activity and lower lactate concentration, suggesting an overall more efficient usage of aerobic metabolism; whereas the cave morphotype showed lower CS activity and higher lactate concentration, suggesting a stronger reliance on anaerobic pathways. We also measured white muscle histological variables that have been previously linked to whole-animal metabolism: fiber diameter, number of nuclei per mm of fiber and myonuclear domain (MND) of both morphotypes at 25°C to examine cell-level differences in muscle morphology. However, we found no differences in fiber diameter, number of nuclei per mm of fiber or MND between the two morphotypes. Thus, although the cellular morphology is similar in these species, the environmental differences in the evolution of the two morphs has led to differences in their metabolic profiles.

Associations of Secretory Activation Breast Milk Biomarkers with Breastfeeding Outcome Measures.

OBJECTIVE: The objective of this study was to explore associations between day 10 postpartum (D10) secretory activation biomarkers and the breastfeeding outcome measures. STUDY DESIGN: This prospective longitudinal descriptive study collected antepartum, D10, and day 60 postpartum (D60) questionnaire data and D10 milk samples. Protein, lactose, and citrate were analyzed with enzymatic spectrophotometric assays. Sodium and potassium were analyzed with inductively coupled plasma optical emission spectrophotometry. Group comparison data were analyzed using χ2, Fisher exact, and independent sample t tests, as appropriate, using SPSS for Mac (version 28). RESULTS: Participants (n = 92) provided a D10 breastmilk sample and completed D10 questionnaires, and 83 completed D60 questionnaires. Participants with D10 impaired secretory activation sodium (>23.0 mM) were more likely to report D10 perceived insufficient milk supply, χ2 = 7.002, P < .05; and less D10 feeding/pumping frequency a day, P < .05; and partial breastfeeding at D60, P < .05. Additionally, participants with D10 impaired secretory activation sodium-to-potassium ratio (sodium: potassium) > 0.8 were more likely to partially breastfeed at D60, P < .05. CONCLUSION: Elevated milk sodium and sodium: potassium are biomarkers related to variables indicative of low milk supply. Therefore, immediate milk testing can be useful in identifying lactation compromise and improving breastfeeding duration. Because breastfeeding affords maternal and infant health benefits, clinicians should identify ways to measure lactation compromise in conjunction with an examination and clinical history to provide early interventions to increase breastfeeding duration and exclusivity.

Early maturation of corpus luteum in rabbits - effect of sildenafil citrate on luteolytic capacity in the early luteal period

Background: Prostaglandin F2 alpha (PGF2 α) binds to the specific receptor (PTGFR) on the corpus luteum (CL) in mammals, inducing regression of the CL structure (luteolysis) and initiating a new cycle. While PGF2 α is effective only on mature CL, the immature CL structure (early luteal phase) resists PGF2 α. In this study, sildenafil citrate, which is used to increase blood flow in the genital organs for treating specific pregnancy issues in women, was administered during the early luteal phase in a rabbit model to test the hypothesis of enhancing blood flow to the CL, thereby promoting earlier maturation and enabling a response to PGF2 α. Materials, Methods & Results: The study was conducted in 2 sub-studies: clinical and molecular. A large number of rabbits were initially included in the sub-studies to ensure a sufficient number of pseudo-pregnant rabbits. Ovulation in rabbits was induced with buserelin acetate and was considered as day 0 of the study. The sub-studies were continued with rabbits whose pseudo-pregnancies were confirmed according to progesterone (P4 ) results. As a result, the studies were continued with a total of 41 pseudo-pregnant New Zealand female rabbits, 21 of which were included in the clinical sub-study and 20 in the molecular sub-study. In both sub-studies, on day 3 of the luteal period, rabbits in the treatment group received 5 mg/kg sildenafil citrate and all rabbits received a single dose of exogenous PGF2 α on day 4 to induce luteolysis. In the clinical sub-study, echotexture and intraovarian blood flow changes in the ovaries were determined by ultrasonography (USG) examination. In the molecular sub-study, the expression changes of Hypoxia Inducible Factor 1 Alpha (HIF1A) and Vascular Endothelial Growth Factor (VEGF) related to angiogenesis, Steroidogenic Acute Regulatory Protein (StAR) related to P4 metabolism, Prostaglandin-Endoperoxide Synthase 2 (PTGS2) related to prostaglandin (PG) mechanism and 15-Hydroxyprostaglandin Dehydrogenase (HPGD) genes at mRNA level were determined using Real Time Polymerase Chain Reaction (RT-PCR) in CL tissues obtained with ovariohysterectomy (OVH) at 1 and 12 h after PGF2 α injection. In addition, blood samples were collected for determine P4 levels from all rabbits. In the clinical sub-study; there was no difference between the groups in mean gray values (MGV), whereas there was a significant decrease in both pulsatile index (PI) and resistance index (RI) values at 40 min after PGF2 α injection (P < 0.05). In the molecular sub-study, it was determined that sildenafil citrate had no significant effect (P > 0.05) on the expression levels 1 and 12 h after PGF2 α injection. According to the results of the molecular sub-study, no significant effect of sildenafil citrate on the mRNA expression levels in the investigated genes was detected (P > 0.05). However, within each group, differences were found according to OVH time after PGF2 α injection. It was observed that PTGS2 and HPGD mRNA expressions decreased at the 12th h compared to the 1st h, while HIF1A expression increased (P < 0.05). Discussion: According to the results obtained from clinical and molecular sub-studies, it was determined that a single dose of sildenafil citrate (5 mg/kg) applied on the 3rd day of the luteal period did not contribute to the maturation process of the CL, did not increase blood flow, and was insufficient to break the resistance of the CL against PGF2 α applied on the 4th day of the luteal period. However, a significant decrease in the PI value at the 40th min after PGF2 α injection suggests that sildenafil citrate has a supportive effect, and that this decrease is also seen in the RI value, suggesting that its effect is insufficient against the vasoconstrictive effect of PGF2 α.

Thermodynamic Study of Leaching Conditions of Galena with Citrate Ions and Hydrogen Peroxide as Oxidizing Agent.

Galena is the most important mineral for lead production, as it is the main source of lead in the world. Currently, the concentrates of this mineral are mainly treated using pyrometallurgical methods, creating several environmental problems, such as the generation of toxic and greenhouse gases. In addition, these processes involve high energy consumption, which limits their applicability. Hydrometallurgical routes are proposed as alternative processes for obtaining some metals such as silver, copper, gold, etc. The drawback of these processes is that the minerals tend to be passive in aqueous media. To mitigate this issue, researchers have used extreme conditions of pressure and temperature (6 atm. and 155 °C) or the use of very corrosive conditions. In this sense, the use of complexing agents that dissolve the metals of interest has been proposed. Citrate ion is one of the most promising complexing agents for galena leaching, obtaining high percentages of dissolution in relatively short times. Unfortunately, there has not been enough investigation about the concentration optimization of the complexing in the pH range from 5 to 9. In this sense, thermodynamic diagrams, such as the Pourbaix diagrams, are very useful for this purpose. Therefore, in this work, the effects of pH and temperature on the leaching of galena in citrate ion solutions are studied thermodynamically and experimentally. The experimental work was carried out with pure galena samples with a particle size of +149 - 74 µm (-100 + 200 mesh). The results show that higher recoveries were obtained working at a pH of 8 and at temperatures of 30 and 40 °C. The thermodynamic and experimental data demonstrated that the existence of an optimal concentration of citrate ion, due the extraction of lead from galena, has a greater reaction rate at a relatively low initial concentration of 0.3 M. This is due the formation of the complex lead citrate 1 (Pb(cit)-).

Diagnostic Value of D-Dimer and INR in Patients Suspected to Have Prosthetic Valve Dysfunction

ABSTRACT Introduction: Prosthetic valve dysfunction is a potentially critical complication of heart valve replacement. An easy and quickly applicable diagnostic procedure is required for recognizing the prosthetic valve dysfunction. The purpose of this study was to prospectively define the diagnostic value of D-dimer and INR level in predicting prosthetic valve dysfunction. Methods: This cross-sectional study was performed in 70 patients suspected to have prosthetic valve dysfunction admitted to Imam Ali Hospital, affiliated with Kermanshah University of Medical Sciences (KUMS), Kermanshah Province, Iran. Cinefluoroscopy, as the gold standard diagnostic test, was used for the diagnosis of prosthetic valve dysfunction in enrolled patients. Two milliliters of blood from each patient were taken into a tube containing sodium citrate anticoagulant. To evaluate D-dimer, the cutoff value was set at 500 ng/ml. Also, to evaluate international normalized ratio (INR), the cutoff value was set at 2. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) of the serum markers were used to describe predictive properties. Results: Of 70 patients, 27 (38.6%) were male and 43 (61.4%) were female, and the mean age was 54.67±15.11 years (range, 18 to 80 years). Of 70 patients, 27 (38.6%) had prosthetic heart valve malfunction demonstrable by fluoroscopy, and 19 patients (27.1%) had D-dimer levels >500 ng/ml. Elevated D-dimer levels (>500 ng/ml) have been indicated to have sensitivity of 70.4%, and hence an NPV of 84.3%, specificity of 100%, PPV of 100%, NLR of 0.3, and the infinity value of PLR for predicting prosthetic valve dysfunction. There was a significant relationship between fluoroscopy and D-dimer test (P=0.001). A kappa coefficient value of 0.745 indicated a substantial agreement between D-dimer and fluoroscopy testing. Mixing test (combination of D-dimer and INR) showed to have 100% sensitivity, and hence a NPV of 69.8%, specificity of 69.8%, PPV of 51.8%, NLR of 1.41, and PLR of 1.44 for predicting prosthetic valve dysfunction. Conclusion: D-dimer with moderate sensitivity and high specificity is an ideal marker for the diagnosis of prosthetic valve dysfunction in suspected patients. Enhanced plasma D-dimer level is not by itself diagnostic of a prosthetic valve dysfunction but may alert physicians to refer the patient for more detailed examination, preferably by fluoroscopy. Mixing test with 100% sensitivity can apply as a rule-out test.

Fasting and 24-h urine pH in patients with urolithiasis using potassium citrate.

PURPOSE: To evaluate the correlation between the pH readings in 24-h urine and the random fasting specimen in patients with urolithiasis using 2 methods. METHODS: A total of 114 patients with urinary lithiasis using potassium citrate were prospectively analyzed. All patients collected 24-h urine and an additional sample, after nocturnal fasting, collected on the day they brought the 24-h sample at the lab. Two different methods (test strip and digital meter) were used to determine pH values. RESULTS: The pH analysis using strips in the 24-h urine presented a mean value similar to the one obtained in the fasting sample (6.07 ± 0.74 vs. 6.02 ± 0.82, respectively; P > 0.05). The same behavior was seen considering the readings with a digital pH meter (5.8 ± 0.78 vs. 5.75 ± 0.83; P > 0.05). However, readings conducted in the same specimen with pH meter and test strip were dissonant (P < 0.05), suggesting that the colorimetric method is not reliable in the assessment of urinary pH in this population. CONCLUSION: pH assessment in a random urinary specimen proved as efficient as the 24-h urine standard method to monitor patients with kidney stones in the use of potassium citrate. Classical test strip analysis is not sensitive enough to evaluate the urine pH in this population and digital pH meter reading is preferred.

The Effect of Clomiphene Citrate and Letrozole in Apoptotic Pathways and Cell Cycle in Human Primary Cumulus Cells and the Protective Effect of Estradiol.

Clomiphene citrate (CC) and letrozole are ovulatory stimulants that, despite high ovulation rates, achieve low pregnancy rates. This study aimed to investigate the in vitro effects of CC and letrozole, alone or in combination with estradiol, on apoptosis in human cumulus cells. We performed a controlled prospective study using primary cumulus cell cultures from patients undergoing in vitro fertilization (n=22). Alpha-inhibin immunocytochemistry was used to assess cell culture purity and morphology. Cell viability was evaluated by MTT assay, cell cycle status by flow cytometry, and Caspase-3, Bax and SOD-2, and S26 gene expression by qPCR. Cells were treated for 24 hours in 5 conditioned media: CC, CC + estradiol, letrozole, letrozole + estradiol and control. None of the treatments affected cell viability, but letrozole reduced the mean percentage of cells in the S phase compared to control (24.79 versus 21.70, p=0.0014). Clomiphene treatment increased mRNA expression of Bax (4 fold) and SOD-2 (2 fold), which was reversed by co-treatment with estradiol. SOD-2 expression increased in cells treated with letrozole compared to control (4 fold), which was also reversed by estradiol. These findings suggest that clomiphene citrate and letrozole do not significantly affect the viability of human cumulus cells. Still, the expression of genes involved in apoptosis was modulated by these drugs alone and in association with estradiol, suggesting that CC and letrozole may have direct effects on cumulus cells beyond their known mechanisms of action.

Testosterone kinetics on hypogonadal men under clomiphene.

OBJECTIVE: To evaluate total testosterone (TT) kinetics and its predictors 6 months after the discontinuation of clomiphene citrate (CC) in patients with hypogonadism. MATERIALS AND METHODS: Consecutive patients with normal testicles and male hypogonadism defined by TT < 300 ng/dl in the presence of signs or symptoms according to the previous consensus were prospectively evaluated in a urologic outpatient clinic by TT levels at baseline (T0), after a daily dose of 50 mg CC for 40 days (T1), and after the washout period of 6 months of CC discontinuation (T2). RESULTS: Among 75 patients, mean age 56.8 years, testosterone at T1 > 300 ng/dl was achieved by 69 (92%), 450-600 ng/dl by 32 (42.6%), and > 600 ng/dl by 27 (36.0%). 18 subjects (24%) maintained asymptomatic and TT levels over 300 ng/dl at T2. Age negatively related to testosterone response and T1 response > 810 ng/dl predicts a median gain of 166.5 ng/dl at 6 months of CC discontinuation. CONCLUSIONS: CC is a compelling option to treat male hypogonadism, although a chronic treatment is needed in most patients. About one in every four patients respond to a CC short trial to "reboot" the physiology. Further understanding of TT kinetics in these patients in the long term is warranted.

Preclinical evaluation of early multi-organ toxicity induced by liposomal doxorubicin using 67Ga-citrate.

Although liposomal doxorubicin (LPD) is widely used for cancer treatment, knowledge concerning the toxicity induced by this drug in healthy organs and tissues is limited. LPD-induced toxicity studies relative to free doxorubicin (DOX) have focused on cardiotoxicity in tumor-bearing animals. On the other hand, the results on DOX-induced cardiotoxicity depending on gender are controversial. One of the manifestations of toxicity is tissue inflammation. 67Ga-citrate has been used for decades to assess inflammation in various pathologies. In this work, the ex vivo biodistribution of 67Ga-citrate is used to evaluate induced multi-organ toxicity in healthy 10-week-old male and female CD1 mice treated for 5 weeks with LPD. Toxicity in males, determined by 67Ga-citrate, was evident only in the target organs of liposomes (spleen, liver, kidneys, and lungs); the average weight loss was 11% and mortality was 14%. In female mice, 67Ga-citrate revealed a cytotoxic effect in practically all organs, the average weight loss was 37%, and the mortality after the last dose of LPD was 66%. These results confirm the usefulness of 67Ga-citrate and the importance of stratifying by sex in the toxicological evaluation of drugs.

Diagnostic Value of D-Dimer and INR in Patients Suspected to Have Prosthetic Valve Dysfunction.

INTRODUCTION: Prosthetic valve dysfunction is a potentially critical complication of heart valve replacement. An easy and quickly applicable diagnostic procedure is required for recognizing the prosthetic valve dysfunction. The purpose of this study was to prospectively define the diagnostic value of D-dimer and INR level in predicting prosthetic valve dysfunction. METHODS: This cross-sectional study was performed in 70 patients suspected to have prosthetic valve dysfunction admitted to Imam Ali Hospital, affiliated with Kermanshah University of Medical Sciences (KUMS), Kermanshah Province, Iran. Cinefluoroscopy, as the gold standard diagnostic test, was used for the diagnosis of prosthetic valve dysfunction in enrolled patients. Two milliliters of blood from each patient were taken into a tube containing sodium citrate anticoagulant. To evaluate D-dimer, the cutoff value was set at 500 ng/ml. Also, to evaluate international normalized ratio (INR), the cutoff value was set at 2. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) of the serum markers were used to describe predictive properties. RESULTS: Of 70 patients, 27 (38.6%) were male and 43 (61.4%) were female, and the mean age was 54.67±15.11 years (range, 18 to 80 years). Of 70 patients, 27 (38.6%) had prosthetic heart valve malfunction demonstrable by fluoroscopy, and 19 patients (27.1%) had D-dimer levels >500 ng/ml. Elevated D-dimer levels (>500 ng/ml) have been indicated to have sensitivity of 70.4%, and hence an NPV of 84.3%, specificity of 100%, PPV of 100%, NLR of 0.3, and the infinity value of PLR for predicting prosthetic valve dysfunction. There was a significant relationship between fluoroscopy and D-dimer test (P=0.001). A kappa coefficient value of 0.745 indicated a substantial agreement between D-dimer and fluoroscopy testing. Mixing test (combination of D-dimer and INR) showed to have 100% sensitivity, and hence a NPV of 69.8%, specificity of 69.8%, PPV of 51.8%, NLR of 1.41, and PLR of 1.44 for predicting prosthetic valve dysfunction. CONCLUSION: D-dimer with moderate sensitivity and high specificity is an ideal marker for the diagnosis of prosthetic valve dysfunction in suspected patients. Enhanced plasma D-dimer level is not by itself diagnostic of a prosthetic valve dysfunction but may alert physicians to refer the patient for more detailed examination, preferably by fluoroscopy. Mixing test with 100% sensitivity can apply as a rule-out test.

Efectividad de anticoagulación regional con citrato en terapia de reemplazo renal continua / Effectiveness of regional citrate anticoagulation in continuous renal replacement therapy

BACKGROUND: Anticoagulation in continuous renal replacement therapy (CRRT) is essential to counteract the coagulation cascade activation, induced by the dialysis circuit. Heparin is the most widely used anticoagulant, followed by regional citrate anticoagulation (RCA). AIM: To determine the effectiveness and safety of anticoagulant treatment with citrate in CRRT. Material and Methods: Retrospective study of adults in CRRT hospitalized between the years 2014 and 2020 in critical units, who required change to RCA according to established protocols. RESULTS: We studied 24 patients aged 63 ± 13 years (12 females). The reasons for admission were acute kidney injury (AKI) in 80% and stage 5 chronic kidney disease in 20%. The indication of RCA in 75% of patients was by coagulation of more than 3 circuits in 24 hours. The duration of the circuit in RCA was 18.5 ± 4.8 hours versus 11.9 ± 4.9 hours with heparin (p < 0.0001). There were 19 mild complications that did not affect the RCA. Conclusions: RCA is feasible to perform, it is a safe and efficient procedure if it is protocolized, allowing a longer duration of the dialysis circuit.

Tuning HAuCl4/Sodium Citrate Stoichiometry to Fabricate Chitosan-Au Nanocomposites.

Nanocomposite engineering of biosensors, biomaterials, and flexible electronics demand a highly tunable synthesis of precursor materials to achieve enhanced or desired properties. However, this process remains limited due to the need for proper synthesis-property strategies. Herein, we report on the ability to synthesize chitosan-gold nanocomposite thin films (CS/AuNP) with tunable properties by chemically reducing HAuCl4 in chitosan solutions and different HAuCl4/sodium citrate molar relationships. The structure, electrical, and relaxation properties of nanocomposites have been investigated as a function of HAuCl4/sodium citrate molar relation. It was shown that gold particle size, conductivity, Vogel temperature (glass transition), and water content strongly depend upon HAuCl4/sodium citrate relationships. Two relaxation processes have been observed in nanocomposites; the α-relaxation process, related to a glass transition in wet CS/AuNP films, and the σ-relaxation related to the local diffusion process of ions in a disordered system. The ability to fine-tune both α- and σ-relaxations may be exploited in the proper design of functional materials for biosensors, biomaterials, and flexible electronics applications.