Creatine supplementation combined with breathing exercises reduces respiratory discomfort and improves creatine status in patients with long-COVID.

ABSTRACT: Eight long-COVID patients with moderate fatigue that had lasted for ≥3 months were recruited. All patients were allocated in a double-blind parallel-group design to receive either 4 g of creatine per day plus breathing exercises (study group) or breathing exercises only (control group) for 3 months. Creatine induced a significant increase in tissue total creatine levels for all 14 locations evaluated in the present study ( P < 0.05), while its levels significantly dropped in the right frontal gray matter and left parietal mesial gray matter at follow-up in the control group ( P < 0.05). No change in time to exhaustion was demonstrated in the control group (P > 0.05), while the mean time to exhaustion was significantly improved for 54 s in the study group post-administration (P = 0.05). These preliminary findings suggest that creatine is as an effective adjuvant therapeutic to breathing exercises for tackling the clinical features in long-COVID.

Reduced tissue creatine levels in patients with long COVID-19: A cross-sectional study.

Total creatine concentration in the skeletal muscle and brain of long COVID patients were significantly lower when compared to the reference values for the general population, as measured with proton magnetic resonance spectroscopy at 1.5-T in vastus medialis muscle, thalamus, and three bilateral cerebral locations across the white and gray matter.

Extensive depolarization and lack of recovery of leech Retzius neurons caused by 2,4 diaminobutyric acid.

In this paper we present, for the first time, a detailed account of electrophysiological effects of 2,4-diaminobutyric acid (2,4-DABA). 2,4-DABA is a neurotoxic non-protein amino acid produced by Cyanobacteria with a possible link to neurodegenerative disorders in animals and humans. Intracellular recordings were performed on Retzius nerve cells of the leech Haemopis sanguisuga using glass microelectrodes filled with 3 mol/L KCl. Our results show that 2,4-DABA is an excitatory amino acid, causing membrane depolarization in a concentration-dependent manner. The most prominent depolarizations of 39.63±2.22 mV and 47.05±4.33 mV, induced by 5×10-3 and 10-2 mol/L 2,4-DABA respectively, are several times larger than maximal depolarizations induced by either Glutamate, Aspartate, ß-N-methylamino-alanine (BMAA) or ß-N-oxalylamino-alanine (BOAA) on our model. These 2,4-DABA induced depolarizations evolve through two distinct stages, which is a novel phenomenon in electrical cell activity upon application of an excitatory amino acid, at least on our model. Involvement of two separate mechanisms, suggested by the two stage phenomenon, is discussed in the paper. We also provide evidence that 2,4-DABA induces irreversible functional disturbances in neurons in a concentration-dependent manner, since only half of the cells recovered normal electrical activity after application of 5×10-3 mol/L 2,4-DABA, and none recovered after application of 10-2 mol/L 2,4-DABA. Effects of both L-2,4-DABA and DL-2,4-DABA were tested and are not significantly different.

Chemicals or mutations that target mitochondrial translation can rescue the respiratory deficiency of yeast bcs1 mutants.

Bcs1p is a chaperone that is required for the incorporation of the Rieske subunit within complex III of the mitochondrial respiratory chain. Mutations in the human gene BCS1L (BCS1-like) are the most frequent nuclear mutations resulting in complex III-related pathologies. In yeast, the mimicking of some pathogenic mutations causes a respiratory deficiency. We have screened chemical libraries and found that two antibiotics, pentamidine and clarithromycin, can compensate two bcs1 point mutations in yeast, one of which is the equivalent of a mutation found in a human patient. As both antibiotics target the large mtrRNA of the mitoribosome, we focused our analysis on mitochondrial translation. We found that the absence of non-essential translation factors Rrf1 or Mif3, which act at the recycling/initiation steps, also compensates for the respiratory deficiency of yeast bcs1 mutations. At compensating concentrations, both antibiotics, as well as the absence of Rrf1, cause an imbalanced synthesis of respiratory subunits which impairs the assembly of the respiratory complexes and especially that of complex IV. Finally, we show that pentamidine also decreases the assembly of complex I in nematode mitochondria. It is well known that complexes III and IV exist within the mitochondrial inner membrane as supramolecular complexes III2/IV in yeast or I/III2/IV in higher eukaryotes. Therefore, we propose that the changes in mitochondrial translation caused by the drugs or by the absence of translation factors, can compensate for bcs1 mutations by modifying the equilibrium between illegitimate, and thus inactive, and active supercomplexes.

MR spectroscopy of hepatic fat and adiponectin and leptin levels during testosterone therapy in type 2 diabetes: a randomized, double-blinded, placebo-controlled trial.

BACKGROUND: Men with type 2 diabetes mellitus (T2D) often have lowered testosterone levels and an increased risk of cardiovascular disease (CVD). Ectopic fat increases the risk of CVD, whereas subcutaneous gluteofemoral fat protects against CVD and has a beneficial adipokine-secreting profile. HYPOTHESIS: Testosterone replacement therapy (TRT) may reduce the content of ectopic fat and improve the adipokine profile in men with T2D. DESIGN AND METHODS: A randomized, double-blinded, placebo-controlled study in 39 men aged 50-70 years with T2D and bioavailable testosterone levels <7.3 nmol/L. Patients were randomized to TRT (n = 20) or placebo gel (n = 19) for 24 weeks. Thigh subcutaneous fat area (TFA, %fat of total thigh volume), subcutaneous abdominal adipose tissue (SAT, % fat of total abdominal volume) and visceral adipose tissue (VAT, % fat of total abdominal volume) were measured by magnetic resonance (MR) imaging. Hepatic fat content was estimated by single-voxel MR spectroscopy. Adiponectin and leptin levels were measured by in-house immunofluorometric assay. Coefficients (b) represent the placebo-controlled mean effect of intervention. RESULTS: TFA (b = -3.3 percentage points (pp), P = 0.009), SAT (b = -3.0 pp, P = 0.006), levels of adiponectin (b = -0.4 mg/L, P = 0.045), leptin (b = -4.3 µg/mL, P < 0.001), leptin:adiponectin ratio (b = -0.53, P = 0.001) and HDL cholesterol (b = -0.11 mmol/L, P = 0.009) decreased during TRT compared with placebo. Hepatic fat content and VAT were unchanged. CONCLUSIONS: The effects of TRT on cardiovascular risk markers were ambiguous. We observed potentially harmful changes in cardiovascular risk parameters, markedly reduced subcutaneous fat and unchanged ectopic fat during TRT and a reduction in adiponectin levels. On the other hand, the decrease in leptin and leptin:adiponectin ratio assessments could reflect an amelioration of the cardiovascular risk profile linked to hyperleptinaemia in ageing men with T2D.

Is lymphocytic thyroiditis a unique type or merely a type of Hashimoto's thyroiditis?

AIM: Objective of the study was to clarify the role of apoptosis in the pathogenesis of lymphocytic thyroiditis (LT) and the existence of difference between Hashimoto's thyroiditis (HT) and LT. METHODS: We evaluated levels of antithyroglobulin and antithyroperoxidase antibodies, the apoptosis by in situ Cell Death Detection-TUNEL and the expression of Bcl2 and Bax by immunohistochemistry in thyroid tissues from 16 patient with HT, 10 with LT and 10 with euthyroid goiter-EG (control group). RESULTS: It was found that apoptosis of thyrocytes in HT (mean 3.05%, SD 1.29%) and LT (mean 2.70%, SD 1.17%) was statistically significantly higher than EG (mean 0.56%, SD 0.23%), but the difference in the percentage of thyrocytes between HT and LT was not statistically significant. In HT the percentage of apoptotic infiltrating lymphocytes (mean 0.59%, SD 0.23%) was smaller than in EG (mean 2.26%, SD 1.42%), but it showed no significant difference in comparison to LT. The expression of Bax in infiltrating lymphocytes in HT (mean 0.72%, SD 0.34%) was statistically significantly higher than LT (mean 0.11%, SD 0.06%). The level of thyroglobulin was lower in HT compared to LT (P<0.01) and compared to EG (P<0.01). The level of antithyroglobulin/antithyroperoxidase antibodies was higher in HT compared to LT (P<0.01) and compared to EG (P<0.01). There was no statistically significant difference in the level of thyroglobulin and level of antibodies between LT and EG. CONCLUSION: These results suppose that apoptosis represents one of significant mechanisms in the pathogenesis of both HT and LT and that LT probably differs from HT.

The role of MR spectroscopy in neurooncology.

Magnetic resonance spectroscopy (MRS) is a diagnostic tool that provides information related to brain's metabolic activity. Literature data suggest that elevation of the ratio between the choline and creatine (the Cho/Cr ratio), the reduction of the ratio between n-acetyl-aspartate acid and creatine (the NAA/Cr ratio), increase of the ratio between myo-inositol and creatine (the MI/Cr ratio), and the presence of lipids and lactate are useful diagnostic markers in grading tumors as well as in the prediction of tumor malignancy potential. Two additional important roles of MRS are differentiation between recurrent tumor and radiation necrosis and evaluation of peritumoral region.

Are irreversible morphological [corrected] signs of portal hypertension in neurological form of Wilson's disease associated with treatment delay? A pilot study.

Aim of this study was to evaluate the rate of morphological liver and spleen abnormalities in patients with neurological clinical presentation of Wilson's disease (WD). Fourteen patients with neurological presentation of WD divided into group A (5 patients who initiated chelating therapy <24 months from the first symptoms) and group B (9 patients whose therapy started ≥24 months after the initial symptoms) underwent abdominal MRI examination. Abnormal findings on abdominal MRI were present in 28% of patients with neurological form of WD. Significant hepatosplenomegaly was present in none of the patients from group A and in 4 (44%) patients from group B. In addition, macronodular liver cirrhosis and peritoneal effusion were evident in two and one patient from group B, respectively, and in none of the patients from group A. Our results suggest that severe portal hypertension and liver damage in patients with neurological presentation of WD might be reversible or do not even develop if chelating treatment is initiated <2 years after the onset of symptoms.

Progressive multifocal leukoencephalopathy associated with mycophenolate mofetil treatment in a woman with lupus and CD4+ T-lymphocyte deficiency.

There is an increase in the number of patients with systemic lupus erythematosus (SLE) reported as developing progressive multifocal leukoencephalopathy (PML) while on intensive immunosuppressive therapy. A 39-year-old HIV-negative woman with a 10-year history of SLE presented with progressive left-side weakness while on maintenance therapy with oral prednisone and mycophenolate mofetil (MMF). On several occasions low CD4+ T-lymphocyte counts were found (68/µL). Brain magnetic resonance imaging (MRI) revealed a large lesion in the right subcortical fronto-parietal region and a smaller one in the left frontal subcortex, corresponding to the PML. In cerebrospinal fluid, polymerase chain reaction (PCR) for JC virus (JCV) was negative, but anti-JCV antibodies were highly positive. Diagnosis of probable PML was made and MMF was withdrawn. The patient's condition improved with marked reduction of left-side weakness and an increase in CD4(+) T-lymphocyte count (141/µL). Follow-up MRI showed regression of lesions and over the next 6 months the patient remained stable. In spite of the grave prognosis associated with PML, SLE patients can have an excellent outcome if immunosuppressants are discontinued as soon as the correct diagnosis is made. SLE patients with associated low CD4(+) T-lymphocyte counts should be monitored for the development of PML during immunosuppressive therapy in particular.

Peritubular membrane potential in kidney proximal tubular cells of spontaneously hypertensive rats.

Peritubular membrane potential in kidney proximal tubular cells of spontaneously hypertensive rats (SHR-Okamoto strain adult rats) was measured with conventional 3 mol KCl microelectrodes, in vivo. Peritubular cell membrane potential was not different in SHR (-66.5 ± 0.7 mV) as compared with normotensive control Wistar rats (-67.5 ± 1.2 mV). To test the effects of possible altered sodium membrane transport in SHR on proximal tubule peritubular membrane potential, we allowed SHR and control rats to drink 1% NaCl for two weeks. Again, proximal tubule peritubular membrane potential was not different in SHR on 1% NaCl (-67.0 ± 1.0 mV) as compared with control rats on 1% NaCl (-64.7 ± 1.3 mV). From these results we concluded that peritubular membrane potential in kidney proximal tubular cells of SHR was not different from normotensive Wistar control rats, and if some alteration of sodium transport in kidney proximal tubular cells of SHR could exist, that was not possible to evaluate from the measurements of peritubular membrane potential in kidney proximal tubular cells.

Differential expression of KCNQ1 K+ channel in tubular cells of frog kidney.

The aim of this study was to evaluate KCNQ1 K+ channel expression in the frog kidney of Rana esculenta. KCNQ1 K+ channel, also known as KvLQT1, is the pore forming a-subunit of the IKs K+ channel, a delayed rectifier voltage-gated K+ channel, which has an important role in water and salt transport in the kidney and gastrointestinal tract. The expression of KCNQ1 K+ channel along tubular epithelium differs from species to species. In the present study the expression of KCNQ1 K+ channel in the frog kidney has been demonstrated by immunohistochemistry. The presence of KCNQ1 K+ channel was demonstrated in the epithelial cells of distal convoluted tubule and collecting duct. However, the pattern of expression of KCNQ1 K+ channel differs between distal convoluted tubules and collecting duct. All epithelial cells of distal convoluted tubules revealed basolateral expression of KCNQ1 K+ channel. On the contrary, only the single cells of collecting duct, probably intercalated cells, showed diffuse cell surface staining with antibodies against KCNQ1 K+ channel. These findings suggest that KCNQ1 K+ channel has cell-specific roles in renal potassium ion transport.

Three-dimensional multivoxel spectroscopy of the healthy hippocampus-are the metabolic differences related to the location?

AIM: The aim of this study was to determine the bilateral distribution of proton metabolites along the long axis of the hippocampus. MATERIALS AND METHODS: Forty-one healthy volunteers were examined using a 1.5T magnetic resonance imaging system, using proton three-dimensional spectroscopic imaging (3D CSI) of the left and the right hippocampus separately. Three dominant signals were measured: choline (Cho), total creatine (tCr), and n-acetylaspartate (NAA) and expressed as ratios of Cho:tCr, NAA:tCr, NAA:Cho and NAA:(Cho+tCr). We compared the data from three hippocampal regions: head, body and tail. RESULTS: Lower NAA:tCr ratios were found in head compared with the body (p<0.05) and in the head compared with the tail (p<0.05) bilaterally. Lower NAA:Cho and NAA:(Cho+tCr) ratios were found in the head compared with the body (p<0.05), in the body compared with the tail (p<0.05), and in the head compared with the tail (p<0.05) bilaterally. There was no statistically significant difference between the left and the right hippocampus. CONCLUSION: Ratios of NAA:tCr, NAA:Cho, and NAA:(Cho+tCr) in hippocampal tissue were significantly higher posteriorly than anteriorly. As the differences are present in healthy volunteers, the appearance in patients related to approximate voxel positioning within hippocampi may result in false-positive results.

Overlooked early CT signs of cerebral venous thrombosis with lethal outcome.

The aim of this report is to emphasize the consequences of overlooked initial CT signs of cerebral venous thrombosis. Brain CT was ordered in an afebrile patient with neck pain and occipital headache. Since no abnormalities were noted on non-contrast CT study, the patient was discharged with recommendation for routine laboratory tests and plain X-ray of the cervical spine. Right hemiparesis developed the next day with persistent headache and the patient was sent back to the Neurology Clinic where he developed myoclonic seizures compatible with focal motor status epilepticus. Neuroimaging, performed two days later, revealed a huge hemorrhagic venous infarcts in the left posterior cerebral hemisphere associated with typical signs of dural sinus thrombosis. Subtle curvilinear hyperdensities were detected within the left parietal cortico-subcortical border zone on reevaluation of the initial brain CT. A posteriori these were thought to be compatible with a developing venous infarct, associated with subtle signs most consistent with combined cortical vein and sinus thrombosis. No improvement was noted after administration of anticoagulant treatment and the patient died 11 days after the initial CT scan. Detection of early CT signs of cerebral venous thrombosis is extremely important, since delaying adequate treatment may have catastrophic consequences.

Serum beta2-microglobulin as a marker of congenital toxoplasmosis and cytomegalovirus infection in preterm neonates.

BACKGROUND: Fetal serum beta(2)-microglobulin (beta(2)M) has been reported as a reliable indicator of fetal infectious diseases. OBJECTIVES: To evaluate serum beta(2)M as a marker of congenital toxoplasmosis or cytomegalovirus (CMV) infection in neonates. METHODS: beta(2)M was retrospectively measured in 72 neonatal serum samples from preterm neonates. Of these, 32 originated from neonates with serological evidence of congenital toxoplasmosis (n = 12) and CMV infection (n = 20), while 40 samples from neonates in which both infections were serologically excluded served as controls. beta(2)M levels were compared between the infection and control groups. RESULTS: Mean (+/-SEM) beta(2)M levels were significantly higher in the groups of neonates infected with Toxoplasma (5.64 +/- 0.61 mg/l) (p = 0.014) and CMV (6.06 +/- 0.66 mg/l) (p < 0.0001) than in the control group (3.80 +/- 0.2). Against the cut-off level of 5 mg/l, beta(2)M was normal in 36 of the 40 uninfected neonates examined, indicating a specificity of 90%. In contrast, it was elevated in 66.7% (8/12) and 65% (13/20) of the Toxoplasma and CMV-infected neonates, respectively, indicating an overall sensitivity of 66%. CONCLUSIONS: In the absence of urogenital disorders, an increase in beta(2)M in neonates is likely to be infection-induced. We showed that serum beta(2)M is increased in congenital toxoplasmosis and CMV infection in the first weeks of life.

Malignant peripheral nerve sheath tumor of the oculomotor nerve.

We present the short-term follow-up magnetic resonance (MR) studies and 1H-MR spectroscopy in a child with malignant peripheral nerve sheath tumor of the oculomotor nerve associated with other less aggressive cranial nerve schwannomas. The tumor revealed perineural extension and diffuse nerve involvement besides rapid growth. 1H-MR spectroscopy was helpful in excluding an intra-axial neoplasm with exophytic growth, mainly due to the absence of creatine and N-acetyl aspartate peaks, and markedly elevated choline peak.

The Croatian version of the Childhood Health Assessment Questionnaire (CHAQ) and the Child Health Questionnaire (CHQ).

We report herein the results of the cross-cultural adaptation and validation into the Croatian language of the parent's version of two health related quality of life instruments. The Childhood Health Assessment Questionnaire (CHAQ) is a disease specific health instrument that measures functional ability in daily living activities in children with juvenile idiopathic arthritis (JIA). The Child Health Questionnaire (CHQ) is a generic health instrument designed to capture the physical and psychosocial well-being of children independently from the underlying disease. The Croatian CHAQ-CHQ were fully validated with 3 forward and 3 backward translations. A total of 139 subjects were enrolled: 75 patients with JIA (19% systemic onset, 20% polyarticular onset, 17% extended oligoarticular subtype, and 44% persistent oligoarticular subtype) and 64 healthy children. CHAQ clinically discriminated between healthy subjects and JIA patients, with the polyarticular and extended oligoarticular subtypes having a higher degree of disability, pain, and a lower overall well-being when compared to their healthy peers. Also the CHQ clinically discriminated between healthy subjects and JIA patients, with the polyarticular onset and extended oligoarticular subtypes having a lower physical and psychosocial well-being when compared to their healthy peers. In conclusion the Croatian version of the CHAQ-CHQ is a reliable, and valid tool for the functional, physical and psychosocial assessment of children with JIA.