Hristo Valkov

ORCID: 0000-0003-3001-3278
Publications
Citations
Views
---
Saved
---
About
Contact & Profiles
Research Areas
  • Helicobacter pylori-related gastroenterology studies
  • Gastroesophageal reflux and treatments
  • Gastrointestinal disorders and treatments
  • Gastrointestinal motility and disorders
  • Photodynamic Therapy Research Studies
  • Gastric Cancer Management and Outcomes
  • Microscopic Colitis
  • Esophageal and GI Pathology
  • Optical Imaging and Spectroscopy Techniques
  • Veterinary medicine and infectious diseases
  • Gastrointestinal Bleeding Diagnosis and Treatment
  • Nanoplatforms for cancer theranostics
  • Eosinophilic Esophagitis
  • Cancer Research and Treatments
  • Optical Polarization and Ellipsometry
  • Infant Health and Development
  • Whipple's Disease and Interleukins
  • Pancreatitis Pathology and Treatment
  • Diagnosis and treatment of tuberculosis
  • Medical and Biological Ozone Research
  • Dysphagia Assessment and Management
  • Diverticular Disease and Complications
  • Cervical and Thoracic Myelopathy
  • COVID-19 Clinical Research Studies
  • Clostridium difficile and Clostridium perfringens research

Queen Giovanna Hospital
2019-2024

Medical University of Sofia
2019-2024

Alexandrovska Hospital
2021

Aims: We aimed to evaluate the prevalence of irritable bowel syndrome (IBS), functional dyspepsia (FD), and their overlap (OS) in Bulgarian population assess risk factors associated with these disorders.
 Methods: sent an internet-based survey adults. The collected data on socio- demographic, behavioral lifestyle characteristics, diagnostic questions following Rome IV criteria IBS, FD occurrence.
 Results: Data was from 1,896 individuals (mean age = 35.5 years, 18-65, SD=11.7),...

10.15403/jgld-2645 article EN Journal of Gastrointestinal and Liver Diseases 2020-09-09

An overly exuberant immune response, characterized by a cytokine storm and uncontrolled inflammation, has been identified as significant driver of severe coronavirus disease 2019 (COVID-19) cases. Consequently, deciphering the intricacies dysregulation in COVID-19 is imperative to identify specific targets for intervention modulation. With these delicate dynamics mind, immunomodulatory therapies have emerged promising avenue mitigating challenges posed COVID-19. Precision manipulating...

10.5501/wjv.v13.i2.92521 article EN World Journal of Virology 2024-06-24

Bile acid malabsorption is common in microscopic colitis, irritable bowel syndrome with diarrhea, and inflammatory disease. We investigated the diagnostic accuracy of 7-alfa-hydroxy-4-cholesten-3-one compared it fibroblast growth factor-19 as biomarkers for bile malabsorption.We enrolled consecutively 109 chronic diarrhea patients standard laboratory tests, fecal calprotectin, endoscopy separated into six groups: n = 30 active disease, 21 disease remission reporting >3 movements per day,...

10.1097/meg.0000000000001925 article EN European Journal of Gastroenterology & Hepatology 2020-11-10

In chronic diarrhea patients, massive over-reporting symptom-based criteria for functional bowel disorders are pitfalls. There is currently no objective biomarker that may provide a correct correlation with the severity of diarrhea. To clarify role fibroblast growth factor-19 (FGF-19) as measurements in comparison patientreported outcome, based on Bristol Stool Form (BSF) Scale.Consecutive 100 patients underwent standard investigations laboratory tests, fecal calprotectin (FC), endoscopy...

10.5152/tjg.2021.20247 article EN The Turkish Journal of Gastroenterology 2021-06-24

Helicobacter pylori (H. pylori) infection is spread worldwide and affects at least half of the world's population. Infected people are increased risk several diseases' development, including gastric adenocarcinoma. The aim this study was to screen patients with dyspeptic symptoms for H. assess Clarithromycin resistance prevalence among infected patients.Screening performed in all using molecular test based on Real-Time Polymerase Chain Reaction (RT-PCR) feces after RNA-DNA extraction. Stool...

10.26355/eurrev_202108_26461 article EN DOAJ (DOAJ: Directory of Open Access Journals) 2021-08-01

Abstract Background Cytomegalovirus (CMV) infection is associated with more flare-ups and deteriorates the prognosis of active inflammatory bowel disease (IBD). Patients refractory IBD should be tested for CMV colitis, especially if they are not responding to immunosuppressive therapy. The prevalence co-infection ranges from 10% 30% in steroid-refractory acute colitis. Concurrent CMV-colitis an increased risk worse therapeutic outcomes, resistance corticosteroids, need salvage One two gold...

10.1093/ecco-jcc/jjad212.1348 article EN Journal of Crohn s and Colitis 2024-01-01

Abstract Background The United Registries for Clinical Assessment and Research (UR-CARE) platform aims to facilitate improve the daily clinical care of patients with Inflammatory Bowel Disease (IBD). possibility updating medical data in UR-CARE at each patient visit allows strict follow-up enables doctor draw relevant recommendations. study is aimed identifying registered IBD increased risk colorectal cancer (CRC) via UR-CARE. Methods Outpatients inpatients a confirmed diagnosis, who had...

10.1093/ecco-jcc/jjad212.0633 article EN Journal of Crohn s and Colitis 2024-01-01

Aims The diagnosis of gastric intestinal metaplasia (GIM) is currently performed by histologic assessment multiple endoscopic biopsies. We aimed to compare the diagnostic yields acetic acid-enhanced narrow-band imaging NBI (AA-NBI) targeted biopsy versus virtual chromoendoscopy for detection preneoplastic conditions as atrophic gastritis (AG)/GIM, lesions (dysplasia), and early cancer (EGC), identify other factors that influence its accuracy using validated grading IM (EGGIM) score in...

10.1055/s-0044-1783549 article EN Endoscopy 2024-04-01

Aims Motorized power spiral enteroscopy (PSE) was introduced as a promising new technique, that offers easier, faster, and more complete small bowel deep enteroscopy. There were reports of perforations death, during PSE withdrawal from the market device, due to these adverse events. The aim our study evaluate performance, efficacy, safety report events, found in clinical practice at single tertiary endoscopy center Eastern Europe.

10.1055/s-0044-1783435 article EN Endoscopy 2024-04-01

Abstract The use of polarized light for biomedical diagnostics skin and mucosa has already a long history. Prior studies have shown contrast enhancement the polarimetric values in images cancerous healthy zones tissues. In present study, reflectance-geometry polarization measurements were made with gastrointestinal tissue (GIT) samples containing normal neoplastic mucosa. We investigated ex vivo characteristic differences parameters, including Stokes vector elements, degree polarization,...

10.1088/1742-6596/1859/1/012041 article EN Journal of Physics Conference Series 2021-03-01

Macroscopic fluorescence spectroscopy parameters of colon benign and malignant tissues were obtained with spectrofluorimeter FluoroLog 3 (HORIBA Jobin Yvon, France). Investigated biological tissue samples excised during standard surgical procedure for tumour removal, cancerous healthy the measurements are performed as soon possible after excision. The stored in safe-keeping perfusion solution isothermal conditions transported from hospital to laboratory. excitation wavelengths range 280-440...

10.1117/12.2559559 article EN 2020-04-09

To evaluate the sensitivity, specificity and predictive value of acetic acid-enhanced NBI (AA-NBI) or crystal violet-enhanced (CV-NBI) versus white-light endoscopy (WLE) using endoscopic grading gastric intestinal metaplasia (EGGIM) simplified classification compare to Operative Link for Gastritis assessment based on Intestinal Metaplasia (OLGIM/OLGA) in patients referred upper with suspected (GIM).

10.1055/s-0039-1681237 article EN Endoscopy 2019-03-18

Helicobacter pylori (H. pylori) is a Gram-negative spiral bacterium commonly found in the stomach. Major part of world's population infected with H. and at increased risk severe gastritis, peptic ulcer disease, gastric cancer. Most studied virulence factors are cytotoxin-associated gene (CagA) vacuolating cytotoxin A (VacA). The infection diagnosed by invasive (histological examination, culture, rapid urease test, which require endoscopy biopsy) noninvasive methods (serology, urea breath...

10.5772/intechopen.86963 article EN cc-by IntechOpen eBooks 2019-09-02

Abstract Background Bile acid diarrhoea (BAD) is a condition when excessive bile acids (BAs) enter the colon due to malabsorption (BAM). Impaired metabolism of BAs and BAM interaction are involved in pathophysiology microscopic colitis (MC) inflammatory bowel disease (IBD), especially Crohn’s (CD). Plasma levels 7-alfa-hydroxy-4-cholesten-3-one (C4) new biomarker BA synthesis. Little known about mechanisms dysregulation C4 patients with IBD, irritable syndrome (IBS-D) (MC). Methods The aim...

10.1093/ecco-jcc/jjz203.346 article EN Journal of Crohn s and Colitis 2020-01-01

Aims To evaluate the percentage of reached key performance measures for Endoscopic retrograde cholangio-pancreatography (ERCP) during advance endoscopy training in young postgraduate fellow.

10.1055/s-0040-1704781 article EN Endoscopy 2020-04-01

10.12968/hmed.2020.0614 article EN British Journal of Hospital Medicine 2021-03-02

Abstract Endogenous fluorescence measurements using UV-VIS excitation wavelengths revealed a variety of natural fluorophores, including the amino acids tyrosine and tryptophan, coenzymes – NADH flavin, collagen elastin. Deep minima in tumor signals were observed region 540 575 nm related to re-absorption hemoglobin. Such high haemoglobin content was also found as an indication tumor’s vascularization it clearly pronounced all dysplastic sites investigated ex vivo . A photosensitizer from...

10.1088/1742-6596/1859/1/012039 article EN Journal of Physics Conference Series 2021-03-01

Endogenous fluorescence detection of neoplastic tissues could become a sensitive add-in tool for early and precise different tumours in soft tissues. Endoscopic techniques fiber-optical fluorescent probes allow achieving all organs places human body. New light excitation sources detectors with high spectral resolution detecting low-intensity autofluorescence or to distinguish signals specific markers accumulated the tumor cells. The most important moment current development steady-state...

10.1117/12.2589442 article EN 2021-05-04

Abstract Diffuse idiopathic skeletal hyperostosis (DISH) is a common but underdiagnosed systemic disease. It characterized by calcifications affecting mainly the spinal anterior longitudinal ligament. In majority of cases, patients are asymptomatic, cervical osteophytes can sometimes cause hoarseness, dysphagia (DISHphagia) and even dyspnea. Case description: A 61-year-old man was admitted to our department with complaints difficulty in swallowing weight loss. Dysphagia had been increasing...

10.2478/amb-2021-0032 article EN Acta Medica Bulgarica 2021-10-01
Coming Soon ...