Ralf Herwig

Prof. Ralf Herwig

Neuroimmunology, Heimerer College, Pristina, Prishtinë, Kosovo
orcid

Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
Verified
Journal Article
Open access
PDF file
RHRalf Herwig
Ralf Herwig
SSSalvatore Sansalone
Salvatore Sansalone
Objective: We evaluated the effectiveness of pelvic vein embolization with aethoxysclerol in aero-block technique for the treatment of impotence due to venous leakage in men using sildenafil for intercourse. The aim of the procedure was to reduce the use of sildenafil. Methods: A total of 96 patients with veno-occlusive dysfunction, severe enough for the need of PDE5 inhibitors for vaginal penetration, underwent pelvic venoablation with aethoxysclerol. The mean patient age was 53.5 years. Venous leaks were identified by Color Doppler Ultrasound after intracavernous alprostadil injection. Under local anesthesia a 20-gauge needle was inserted into the deep dorsal penile vein. The pelvic venogram was obtained through deep dorsal venography. Aethoxysclerol 3% as sclerosing agent was injected after air-block under Valsalva manoeuver. Success was defined as the ability to achieve vaginal insertion without the aid of any drugs, vasoactive injections, penile prosthesis, or vacuum device. Additionally, a pre- and post- therapy IIEF score and a digital overnight spontaneous erections protocol (OSEP) with the NEVA™-system was performed. Results: At 3 month follow-up 77 out of 96 patients (80.21%) reported to have erections sufficient for vaginal insertion without the use of any drug or additional device. Four (4.17%) patients did not report any improvement. Follow up with color Doppler ultrasound revealed a new or persistent venous leakage in 8 (8.33%) of the patients. No serious complications occurred. Conclusions: Our new pelvic venoablation technique using aethoxysclerol in air-block technique was effective, minimally invasive, and cost-effective. All patients were able to perform sexual intercourse without the previously used dosage of PDE5 inhibitor. This new method may help in patients with contra-indications against PDE5 inhibitors, in patients who cannot afford the frequent usage of expensive oral medication or those who do not fully respond to PDE5-inhibitors.

10 December 2022 in Genes
Verified
Journal Article
Open access
PDF file
Asma BashirAsma Bashir
Asma Bashir
KAKashif Ali
Kashif Ali
KBKhair Bux
Khair Bux
NFNeha Farid
Neha Farid
MKMitra Khaireabadi
Mitra Khaireabadi
RHRalf Herwig
Ralf Herwig
Bacteriocins are gaining immense importance in therapeutics since they show significant antibacterial potential. This study reports the bacteriocin KAE01 from Enterococcus faecium, along with its characterization, molecular modeling, and antibacterial potency, by targeting the matrix protein of Pseudomonas aeruginosa. The bacteriocin was purified by using ammonium sulfate precipitation and fast protein liquid chromatography (FPLC), and its molecular weight was estimated as 55 kDa by means of SDS-PAGE. The bacteriocin was found to show stability in a wide range of pH values (2.0–10.0) and temperatures (100 °C for 1 h and 121 °C for 15 min). Antimicrobial screening of the purified peptide against different strains of P. aeruginosa showed its significant antibacterial potential. Scanning electron microscopy of bacteriocin-induced bacterial cultures revealed significant changes in the cellular morphology of the pathogens. In silico molecular modeling of KAE01, followed by molecular docking of the matrix protein (qSA) of P. aeruginosa and KAE01, supported the antibacterial potency and SEM findings of this study.

Verified
Journal Article
Open access
PDF file
JGJoachim Mag. Dr. Greilberger
Joachim Mag. Dr. Greilberger
RHRalf Herwig
Ralf Herwig
MKMEHTAP KACAR
MEHTAP KACAR
NBNaime Brajshori
Naime Brajshori
GFGeorg Feigl
Georg Feigl
RWReinhold Wintersteiger
Reinhold Wintersteiger
Background: We recently showed that a combined solution containing alpha-ketoglutarate (aKG) and 5-hydroxymethyl-furfural (5-HMF) has a solid antitumoral effect on the Jurkat cell line due to the fact of its antioxidative, caspase-3 and apoptosis activities, but no negative effect on human fibroblasts was obtained. The question arises how the single compounds, aKG and 5-HMF, affect peroxynitrite (ONOO−) and nitration of tyrosine residues, Jurkat cell proliferation and caspase-activated apoptosis. Methods: The ONOO− luminol-induced chemiluminescence reaction was used to measure the ONOO− scavenging function of aKG or 5-HMF, and their protection against nitration of tyrosine residues on bovine serum albumin was estimated with the ELISA technique. The Jurkat cell line was cultivated in the absence or presence of aKG or 5-HMF solutions between 0 and 3.5 µM aKG or 0 and 4 µM 5-HMF. Jurkat cells were tested for cell proliferation, mitochondrial activity and caspase-activated apoptosis. Results: aKG showed a concentration-dependent reduction in ONOO−, resulting in a 90% elimination of ONOO− using 200 mM aKG. In addition, 20 and 200 mM 5-HMF were able to reduce ONOO− only by 20%, while lower concentrations of 5-HMF remained stable in the presence of ONOO−. Nitration of tyrosine residues was inhibited 4 fold more effectively with 5-HMF compared to aKG measuring the IC50%. Both substances, aKG and 5-HMF, were shown to cause a reduction in Jurkat cell growth that was dependent on the dose and incubation time. The aKG effectively reduced Jurkat cell growth down to 50% after 48 and 72 h of incubation using the highest concentration of 3.5 µM, and 1, 1.6, 2, 3 and 4 µM 5-HMF inhibited any cell growth within (i) 24 h; 1.6, 2, 3 and 4 µM 5-HMF within 48 h (ii); 2, 3 and 4 µM 5-HMF within 72 h (iii). Furthermore, 4 µM was able to eliminate the starting cell number of 20,000 cells after 48 and 72 h down to 11,233 cells. The mitochondrial activity measurements supported the data on aKG or 5-HMF regarding cell growth in Jurkat cells, in both a dose- and incubation-time-dependent manner: the highest concentration of 3.5 µM aKG reduced the mitochondrial activity over 24 h (67.7%), 48 h (57.9%) and 72 h (46.8%) of incubation with Jurkat cells compared to the control incubation without aKG (100%). 5-HMF was more effective compared to aKG; the mitochondrial activity in the presence of 4 µM 5-HMF decreased after 24 h down to 68.4%, after 48 h to 42.9% and after 72 h to 32.0%. Moreover, 1.7 and 3.4 µM aKG had no effect on caspase-3-activated apoptosis (0.58% and 0.56%) in the Jurkat cell line. However, 2 and 4 µM 5-HMF increased the caspase-3-activated apoptosis up to 22.1% and 42.5% compared to the control (2.9%). A combined solution of 1.7 µM aKG + 0.7 µM 5-HMF showed a higher caspase-3-activated apoptosis (15.7%) compared to 1.7 µM aKG or 2 µM 5-HMF alone. In addition, 3.5 µM µg/mL aKG + 1.7 µM 5-HMF induced caspase-activated apoptosis up to 55.6% compared to 4.5% or 35.6% caspase-3 activity using 3.5 µM aKG or 4 µM 5-HMF. Conclusion: Both substances showed high antioxidative potential in eliminating either peroxynitrite or nitration of tyrosine residues, which results in a better inhibition of cell growth and mitochondrial activity of 5-HMF compared to aKG. However, caspase-3-activated apoptosis measurements revealed that the combination of both substances synergistically is the most effective compared to single compounds.

21 September 2021 in Antioxidants
Verified
Journal Article
Open access
PDF file
JGJoachim Mag. Dr. Greilberger
Joachim Mag. Dr. Greilberger
MGMichaela Greilberger
Michaela Greilberger
RWReinhold Wintersteiger
Reinhold Wintersteiger
KZKlaus Zangger
Klaus Zangger
RHRalf Herwig
Ralf Herwig
The generation of peroxynitrite (ONOO−) is associated with several diseases, including atherosclerosis, hypertension, neurodegeneration, cancer, inflammation, and sepsis. Alpha-ketoglutarate (αKG) is a known potential highly antioxidative agent for radical oxidative species such as peroxides. The question arises as to whether αKG is also a potential scavenger of ONOO− and a potential protector against ONOO−-mediated nitration of proteins. NMR studies of 1 mM αKG in 100 mM phosphate-buffered saline at pH 7.4 and pH 6.0 were carried out in the presence or absence of a final concentration of 2 mM ONOO−. An ONOO−–luminol-induced chemiluminescence reaction was used to measure the scavenging function of several concentrations of αKG; quantification of αKG was performed via spectrophotometric enzymatic assay of αKG in the absence or presence of 0, 1, or 2 mM ONOO−. The nitration of tyrosine residues on proteins was measured on ONOO−-treated bovine serum albumin (BSA) in the presence or absence of 0–24 mM αKG by an ELISA technique using a specific anti-IgG against nitro-tyrosine. The addition of ONOO− to αKG led to the formation of succinic acid and nitrite at pH 7.0, but not at pH 6.0, as αKG was stable against ONOO−. The absorbance of enzymatically estimated αKG at the time point of 30 min was significantly lower in favour of ONOO− (1 mM: 0.21 ± 0.03, 2 mM: 0.12 ± 0.05 vs. 0 mM: 0.32 ± 0.02; p < 0.001). The luminol technique showed an inverse logarithmic correlation of the ONOO− and αKG concentrations (y = −2 × 105 ln(x) + 1 × 106; r2 = 0.99). The usage of 4 mM αKG showed a significant reduction by nearly half in the chemiluminescence signal (284,456 ± 29,293 cps, p < 0.001) compared to the control (474,401 ± 18,259); for 20 and 200 mM αKG, there were further reductions to 163,546 ± 26,196 cps (p < 0.001) and 12,658 ± 1928 cps (p < 0.001). Nitrated tyrosine residues were estimated using the ELISA technique. A negative linear correlation was obtained by estimating nitrated tyrosine residues in the presence of αKG (r2 = 0.94): a reduction by half of nitrated tyrosine was estimated using 12 mM αKG compared to the control (326.1 ± 39.6 nmol vs. 844.5 ± 128.4 nmol; p < 0.001).

15 January 2015 in BioMed Research International
Verified
Journal Article
Open access
PDF file
RHRalf Herwig
Ralf Herwig
MBManfred Bayerl
Manfred Bayerl
Peyronie’s disease is a connective tissue disorder in the soft tissue of the penis. The underlying cause of Peyronie’s disease is not well understood but is thought to be caused by trauma or injury to the penis during sexual intercourse. The purpose of the interdisciplinary cooperation between urological surgery and physics is the development of a physical simulation tool in order to give prognosis of possible tunica albuginea fibre rupture at a certain degree of deviation of the penis. For our group the first challenge was to translate the human organ of the penis into a physical model. Starting and marginal parameters had to be defined, whereby some of them had to be based on assumption, as physical data of the human living tissue have rarely been measured up to now. The algorithm and its dependencies had to be developed. This paper is a first step of a three-dimensional mathematical-physical simulation with the assumption of a 100% filled rigid penis. The calculation gives proof of the hypothesis that the fibre-load-angle of the penis is less than 12 degrees. Thus physical simulation is able to provide the surgeon with a simple instrument to calculate and forecast the risk of the individual patient.

25 July 2022 in Biomedicines
Verified
Journal Article
Open access
PDF file
RHRalf Herwig
Ralf Herwig
KEKatharina Erlbacher
Katharina Erlbacher
AIAmela Ibrahimagic
Amela Ibrahimagic
MKMEHTAP KACAR
MEHTAP KACAR
NBNaime Brajshori
Naime Brajshori
JGJoachim Mag. Dr. Greilberger
Joachim Mag. Dr. Greilberger
Background: Vitamin D3 complexed to deglycosylated vitamin D binding protein (VitD-dgVDBP) is a water-soluble vitamin D dimeric compound (VitD-dgVDBP). It is not clear how VitD-dgVDBP affects circulating monocytes, macrophages, other immune cell systems, including phagocytosis and apoptosis, and the generation of reactive oxygen species (ROS) compared to dgVDBP. Methods: Flow cytometry was used to measure superoxide anion radical (O2*−) levels and macrophage activity in the presence of VitD-dgVDBP or dgVDBP. VitD-dgVDBP was incubated with normal human lymphocytes (nPBMCs), and several clusters of determination (CDs) were estimated. dgVDBP and VitD-dgVDBP apoptosis was estimated on malignant prostatic cells. Results: The macrophage activity was 2.8-fold higher using VitD-dgVDBP (19.8·106 counts) compared to dgVDBP (7.0·106 counts), but O2*− production was 1.8-fold lower in favor of VitD-dgVDBP (355·103 counts) compared to dgVDBP (630·106 counts). The calculated ratio of the radical/macrophage activity was 5-fold lower compared to that of dgVDBP. Only VitD-dgVDBP activated caspase-3 (8%), caspase-9 (13%), and cytochrome-C (11%) on prostatic cancer cells. PE-Cy7-labeled VitD-dgVDBP was found to bind to cytotoxic suppressor cells, monocytes/macrophages, dendritic and natural killer cells (CD8+), and helper cells (CD4+). After 12 h of co-incubation of nPBMCs with VitD-dgVDBP, significant activation and expression were measured for CD16++/CD16 (0.6 ± 0.1% vs. 0.4 ± 0.1%, p < 0.05), CD45k+ (96.0 ± 6.0% vs. 84.7 ± 9.5%, p < 0.05), CD85k+ (24.3 ± 13.2% vs. 3.8 ± 3.2%, p < 0.05), and CD85k+/CD123+ (46.8 ± 8.1% vs. 3.5 ± 3.7%, p < 0.001) compared to the control experiment. No significant difference was found using CD3+, CD4+, CD8+, CD4/CD8, CD4/CD8, CD16+, CD16++, CD14+, or CD123+. A significant decline in CD14+/CD16+ was obtained in the presence of VitD-dgVDBP (0.7 ± 0.2% vs. 3.1 ± 1.7%; p < 0.01). Conclusion: The newly developed water-soluble VitD3 form VitD-dgVDBP affected cytotoxic suppressor cells by activating the low radical-dependent CD16 pathway and seemed to induce apoptosis in malignant prostatic cells.