Synthesis, Characterization and Biological Studies of Organoselenium trans-Palladium(II) Complexes

BACKGROUND

Over the years, transition metal complexes have exhibited significant antimicrobial and antitumor activity. It all started with cisplatin discovery, but due to the large number of side effects it shows, there is a growing need to find a new metal-based compound with higher selectivity and activity on more tumors.

OBJECTIVES

Two novel trans-palladium(II) complexes with organoselenium compounds as ligands, [Pd(L1)₂Cl₂] (L1 = 5-(phenylselanylmethyl)-dihydrofuran-2(3H)-one) and [Pd(L2)₂Cl₂] (L2 = 2- methyl-5-(phenylselanylmethyl)- tetrahydrofuran) were synthesized, in the text referred to as Pd-Se1 and Pd-Se2. Also, a structurally similar trans-palladium(II) complex, [Pd(L3)₂Cl₂] (L3= 2,2- dimethyl-3-(phenylselanylmethyl)-tetrahydro-2H-pyran) was synthesized according to an already published work and is referred to as Pd-Se3. The interaction of synthesized complexes with DNA and bovine serum albumin was observed. Also, antimicrobial activity and in vitro testing, cell viability, and cytotoxic effects of synthesized ligands and complexes on human epithelial colorectal cancer cell line HCT-116 were studied. Molecular docking simulations were performed to understand better the binding modes of the complexes reported in this paper with DNA and BSA, as well as to comprehend their antimicrobial activity.

METHODS

The interactions of the synthesized complexes with DNA and bovine serum albumin were done using UV-Vis and emission spectral studies as well as docking studies. Antimicrobial activity was tested by determining the minimum inhibitory concentrations (MIC) and minimum microbicidal concentration (MMC) using the resazurin microdilution plate method. Cytotoxic activity on cancer cells was studied by MTT test.

RESULTS

The Pd(II) complexes showed a significant binding affinity for calf thymus DNA and bovine serum albumin by UV-Vis and emission spectral studies. The intensity of antimicrobial activity varied with the complexes Pd-Se1 and Pd-Se3, showing significantly higher activity than the corresponding ligand. The most significant activity was shown on Pseudomonas aeruginosa. Under standardized laboratory conditions for in vitro testing, cell viability and cytotoxic effects of synthesized ligands and complexes were studied on human epithelial colorectal cancer cell line HCT-116, where Pd-Se2 showed some significant cytotoxic effects.

CONCLUSION

The newly synthesized complexes have the potential to be further investigated as metallodrugs.

Assessment of patient eligibility for kidney transplant procedure

Kidney transplantation offers better quality of life in comparison to patient dialysis. Patients with endogenous creatinine clearance 30 mL/min/1.73m2 are introduced into the kidney transplant program. Every patient should be assessed for a degree of eligibility for the kidney transplant procedure. Basic principles of eligibility assessment include: patient education, assessment of patient's motivation level, medical risk assessment, as well as evaluation of psychosocial status and the level of family support. Medical risk assessment involves establishing the etiology of the primary kidney disease, cardiovascular status assessment, viral status assessment, risk assessment for renal graft thrombosis, screening for early malignancy detection, assessment of mineral metabolism and bone tissue disorders, and immunological risk assessment. Identification of patients with highest degree of kidney transplant eligibility shall decrease morbidity and mortality, reduce medical costs and improve the quality of life for these patients.

Clinical characteristics of nosocomial infections of patients with acute central nervous system infections treated in ICU

A retrospective study was performed to evaluate the clinical characteristics of nosocomial infections in patients with acute infection of central nervous system (ACNS infections). The study included 1,686 patients admitted to the ICU. Of 1,686 patients, 936 (55.5%) had ACNS infection. Nosocomial infections was confirmed in 221 (23.6%) patients with ACNS infection. The most common risk factors for ICU-acquired nosocomial infections were consciousness disorder, mechanical ventilation and nasogastric tube. The coagulase - negative Staphylococcus aureus was the most frequent isolated pathogen (285 isolates, 56.5%). Results suggest that a persistently high level of therapeutic activity and persistently depressed consciousness after the ICU admission are associated with the occurrence of hospital-acquired infection in critically ill patients hospitalized at a medical ICU.

Characteristics of radiological changes in lungs during varicella zoster viral infection

The objective of this research was to analyse the varicella patients' data in order to determine the following: general frequency of pneumopathies and types of lung changes according to X-ray presentation and the changes on the computed tomography. It examined 101 patients with the clinical presentation of varicella and some of the X-ray entities of varicella pneumopathies. Radiological techniques included chest X-ray and CT scans. Familiarity with clinical, laboratory and radiological characteristics of the disease may be of utmost importance for early recognition.

[Cholera--once and nowadays]

HISTORY

Cholera is an acute intestinal infection which raged in India in the nineteenth century and it broke out in six great pandemics out in Europe.

ETIOLOGY

Cholera is caused by bacteria Vibrio cholerae, which produce an enterotoxin causing massive diarrhoea. There are two biotypes--classic and El Tor.

EPIDEMIOLOGY

The source of Vibrio cholerae is a man. Cholera is a typical faecally-oral infection.

PATHOGENESIS

Ingested by contaminated water and food, Vibrio cholerae comes to the intestinal wall. The tightness is intermediated with toxin-coregulated pilus. There it produces enterotoxin and activates adenilate cyclase which accumulate intracellular cyclic adenosine monophosphate. The result is isotonic watery diarrhoea.

CLINICAL FEATURES

Cholera can occur as asymptomatic infection, then enteritis and deathly classic cholera. Patients suffer from explosive, unremitting, watery diarrhoea (known as "rice water"). DIAGNOSIS AND DIFFERENTIAL DIAGNOSIS: The diagnosis is based on clinical features, epidemiological data and laboratory diagnostic methods. The most important is to isolate Vibrion cholerae from the stool.

THERAPY

The most important treatment for cholera is fluid containing minerals. The best antibiotics available are tetracycline.

PREVENTION

The best preventive measures are water supply, sanitation, food safety and community awareness. The importance of vaccines comes second. CHOLERA NOWADAYS: Cholera has been known since ancient times, but it is present even nowadays. It has been developed as a biological weapon.

CONCLUSION

Cholera is a dreadful intestinal disease with severe clinical features. One thing is known for certain: hygienic and sanitary measures are the main prevention.

[Risk factors and disposition in development of the nervous system infections]

INTRODUCTION

Although well protected, brain is not resistant to infection agents. Acute infections of our nervous system appear more often in children and in persons who have medical history data about previous disorders, especially disorders of the nervous system. It is difficult to list possible risk factors which can be responsible for the appearance of infections of CNS and the resulting conditions. It is often difficult or impossible to determine what previous neural damage was (trauma, anoxic damages etc.) from those appearing during infections of CNS. All-inclusive anamnestic research reduces the possibility of approximate judgements.

MATERIAL AND METHODS

The research was based on the retrospective analysis of medical documentation of 275 patients. All patients were divided into three groups according to the final diagnosis. The first group consisted of 125 patients who were treated for acute virus encephalitis, the second group consisted of 125 patients who were treated for acute bacterial meningoencephalitis and the third group consisted of 25 patients who were treated for cerebritis.

DISCUSSION

In our studies sample, the youngest patient was 3 years old and the oldest was 87 years old. The highest number of patients with virus infection of the CNS was in the group under 25 years of age (45.6%). The highest number of patients with bacterial infections of the CNS and cerebritis was in the group of patients over 45 years of age (64%, 37%).

CONCLUSION

Risk factors were more present in bacterial infections of the nervous system and cerebrit than in virus infection of CNS. In virus infections of the CNS, 28% of patients had some risk factor, most often-chronic ethylism, diabetes mellitus and acquired heart diseases. In bacterial infections of the CNS, 64% of patients had some predisposed factor. The most frequent factor of risk in these patients were chronic otitis (21.6%) and cranio-trauma (14.4%). In cerebritis, risk factors were present in 76% of patients and they were: sepsis (20%), chronic otitis (12%) and systemic lupus erythematosus (8%).

[Altered state of consciousness as a factor affecting the course and consequences of acute viral encephalitis]

INTRODUCTION

Acute viral encephalitis is an infectious disease, which is characterized by sudden onset, serious clinical picture and with an uncertain outcome. Disturbances of consciousness are common in the course of acute viral encephalitis. Consciousness is the heighest form of psychic life and consciousness disturbances may include quantitative (somnolentia, sopor, coma) and qualitative symptoms (convulsions, twilight state).

MATERIAL AND METHODS

We investigated 63 patients with acute viral encephalitis. The youngest patient was 15, and the oldest one 69 years of age. We examined the state of consciousness in all patients.

RESULTS

Of all examined patients, 54 (85.72%) patients had disturbances of consciousness, 9 (14.25%) patients had no conciousness disturbances, 11 (17.46%) patients had sopor and 24 (38.09%) patients were in coma. The highest percentage of lethal outcomes was recorded in coma patients (12.5%). The longer the duration of consciousness disturbances, the higher the mortality among these patients.

DISCUSSION

Subjective and objective factors cause different grades and duration of consciousness disturbances. The highest percentage of patients who recovered without consequences was established in the group of patients (81.82%) with somnolence. The highest percentage of patients who recovered with consequences (20.8%) and patients (12.5%) with lethal outcome was recorded in the group of patients in coma. These findings are in correlation with literature data.

Nosocomial infections in patients with acute central nervous system infections

Due to current increase in the rate of nosocomial infections, our objective was to examine the frequency, risk factors, clinical presentation and etiology of nosocomial infections in patients with central nervous system infections. 2246 patients with central nervous system infections, treated in the intensive care units of the Institute of Infectious and Tropical Diseases, Clinical Center of Serbia in Belgrade and at the Department of Infectious Diseases of the Clinical Hospital Center Kragujevac, were included in this retrospective and prospective study. Clinical manifestations of nosocomial infections were registered in 180 (12.7%) patients. Direct risk factors for nosocomial infections were: venous lines, urinary catheter, length of stay over 20 days, inhibitors of gastric secretion, consciousness disorders and coma, endotracheal intubation, tracheotomy and controlled ventilation for 5 days or more. The most frequent clinical presentations of nosocomial infections were: tract urinary infections, bacteriemia/sepsis and nosocomial pneumonia. Significantly higher frequency of death outcomes was registered in patients with nosocomial infections.

[Weil's syndrome (leptospiral infection): a case report]

INTRODUCTION

Leptospirosis is an acute zoonotic infection, caused by spirochetes of the genus Leptospira. It is characterized by extensive vasculitis. It is usually transmitted indirectly, per contaminated water, rarely directly, through contact with infected animals. Leptospira bacteria commonly enter the body through damaged skin or mucous membranes. The clinical syndromes may vary from a subclinical infection and mild febrile condition to severe clinical symptoms with jaundice and renal failure.

CASE REPORT

This is a case report of a patient with leptospirosis (Weil's disease) whose clinical manifestations included: icterus, renal failure, hemorrhagic syndrome and disturbances of consciousness. After the use of antibiotics, symptomatic and substitution therapy, all symptoms resolved completely. However, in our patient, hemodialysis was necessary due to renal failure, as a palliative measure.

DISCUSSION

Weil's syndrome is a severe form of leptospirosis, which can be fatal. Early clinical diagnosis of the disease, as well as serologic verification of infection, are very important prerequisites, followed by antibiotic and other symptomatic therapy, as soon as possible.

CONCLUSION

This is a case report of a patient with rare clinical manifestations of leptosirosis. Although presenting with severe symptoms, thanks to palliative therapeutic measures, complete and fast recovery was achieved. We especially point out the role of.

[Myopericarditis during acute Epstein-Barr virus infection: a case report]

INTRODUCTION

Complications associated with infectious mononucleosis are rare, but occasionally they can occur involving hematological, neurological, cardiological and pulmological complications, as well as liver and spleen disorders, sometimes with lethal outcome. The most important cardiac complications are myocarditis and pericarditis.

CASE REPORT

An 18-year-old male patient was admitted to the Departement of Infectious Diseasees with clinical picture of infectious mononucelosis, while symptoms appeared 7 days before admission. He was under observation and treatment for nineteen days when clinical, radiographic and echocardiographic findings revealed development of myopericarditis and he was transferred to the Cardiology Department. He was treated with non-steroidal antiinflammatory drugs, beta-blockers, antibiotics and other symptomatic therapy. He became afebrile 35 days after admission, and was discharged on the 50th day in good condition.

DISCUSSION

Myocarditis may develop as a complication of an infectious disease, and is usually caused by a direct viral infection, as well as, toxic and autoimmune mechanisms. Myocarditis attributed to Epstein-Barr virus infection is probably caused by autoimmune mechanisms: autoantibodies activate the complement or cause cellular cytotoxicity.

CONCLUSION

Myopericarditis is not a common complication of acute Epstein-Barr virus infection. Transvenous endomyocardial biopsy is an established method required for exact diagnosis. In this case it was not done, due to some technical reasons. Thus, there is a high probalitiy that this patient had myopericarditis.

Competitive reactions of L-methionine and 5'-GMP towards platinum (II) complexes

The complex-formation reactions of the platinum(II) complexes, [Pt(dien)H2O]2+, [PtCl(dien)]+ and [PtBr(dien)]+ (dien is diethylenetriamine) with some biologically relevant ligands such as inosine (INO), inosine-5'-monophosphate (5'-IMP), guanosine-5'-monophosphate (5'-GMP), glutathione (GSH) and L-methionine (S-meth), were studied by UV-Vis (UV-Visible) spectrophotometry and 1H NMR spectroscopy. Reactions of the [PtCl(dien)]+ with L-methionine were studied in the presence and absence of 5'-GMP. The rate constants clearly showed a kinetic preference toward L-methionine. However, competitive reactions of [PtCl(dien)]+ with L-methionine and 5'-GMP demonstrated initially rapid formation of [Pt(dien)(S-meth)]2+ followed by displacement of L-methionine by 5'-GMP. In the later stages the concentration of [Pt(dien)(N7-GMP )]2+ is predominant. The results are analyzed in reference to the anti-tumour activity of Pt(II) complexes.

[Changes in plasma osmolality in food poisoning]

INTRODUCTION

Changes in plasma osmolality may occur during acute intestinal infections due to dehydration (loss of water and/or electrolytes). Depending on whether the water and electrolyte deficit is primary, or a proportional loss of water and electrolytes, dehydration can be classified into three categories: hypertonic, hypotonic and isotonic.

MATERIAL AND METHODS

Thirty (30) patients with food poisoning were included in this research. All patients were hospitalized because of frequent vomiting, with resultant dehydration. A diagnosis of food poisoning was made based on the clinical picture, short incubation period and positive epidemiological history. Plasma osmolality was measured by a freezing point depression with an osmometer, while effective plasma osmolality was determined by using the following formula: EPO (eff. plasma osmolality) = 2 x serum sodium concentration + serum glucose level. Apart from plasma osmolality, other parameters were also measured in patients' sera: sodium, chloride, potassium, urea, glucose and hematocrit. In order to follow-up the changes in these parameters, they were also measured after treatment of the gastrointestinal disorder. Statistical analysis was performed using the equality of mean values for 2 basic groups.

RESULTS

The statistical results showed that the values of total and effective plasma osmolality (TPO and EPO) among patients with gastrointestinal disorders were not significantly higher than values after the alimentary infection.

DISCUSSION

Such results suggest that food poisoning is associated with disorders of water and electrolyte metabolism, that is isotonic type of dehydration.

[Acute serous meningitis in a patient with erythema infectiosum]

BACKGROUND

Clinical manifestations caused by parvovirus B19 (PVB19) are various and depend on the age and immunity of an infected person. In children, the most frequent clinical manifestation of parvovirus B19 primary infection is erythema infectiosum (EI).

CASE REPORT

In this case report we presented a 12-year-old patient with 2 clinical syndromes: erythema infectiosum and serous meningitis. Erythema infectiosum was manifested as fever, typical skin lesions ("slapped cheeks"), erythematous macules and papules confluent with reticular appearance on the extremities and the trunk. Serous meningitis had a mild course with an increased number of lymphocytes (120/ mm3) and the mildly increased level of proteins (0.75 g/l). The serological examination showed the presence of IgM and IgG antibodies against parvovirus B19 in serum, as well as in cerebrospinal fluid (CSF). The reduction of serum/CSF ratio of IgG antibodies was present. The symptomatic therapy was used in the treatment. The course and the prognosis were benign.

CONCLUSION

Human PVB19, although non-specifically associated with CNS diseases could be an etiological factor that might cause serous meningitis. So, it should be considered in different diagnosis in patients with aseptic meningitis, especially during the outbreaks of erythema infectiosum.

Epstein-Barr virus hepatitis associated withicterus: A case report

Introduction. Primary Epstein-Barr virus infection (EBVI) in children is usually asymptomatic with seroconversion. If primary infection occurs in adolescents or in adulthood, the most common manifestation is acute infectious mononucleosis. The diagnosis of acute infectious mononucleosis is made by virus and serologic tests. The most important evidence of primary EBV infection includes IgM class antibodies detected by using EBV virus-capsidantigen (EBV VCA) which appears at the beginning of illness and usually lasts 1 to 2 months. Paul Bunnell Davidson test, although non-specific, is still in use today in diagnosis of infectious mononucleosis and for detection of heterophile antibodies. Case report. Acute hepatitis with icterus is a rare clinical manifestation in primary EBV infection. However, sometimes it is the only manifestation of the disease. This is a case report of a patient with EBV hepatitis and icterus associated with long-lasting fever without pharyngitis and lymphadenopathy, which are characteristics of infectious mononucleosis. The etiologic diagnosis was confirmed by positive Paul Bunnell Davidson test and by detection of specific antibodies (class IgM) to EBV VCA in patient's serum. Discussion. The pathogenetic mechanism which causes destruction of hepatic cells and provokes cholestasis during EBV infection, has not been cleared yet. It is supposed that EBV has no direct cytocide effects on hepatic cells, yet destruction of these cells is caused by toxic action of free radicals through lipid peroxidation. Patients with infectious mononucleosis have autoantibodies directed against enzyme superoxide-dismutase which neutralizes enzyme's antioxidant action. As a result of this action, free radicals accumulate in hepatic cells and cause their damage. Conclusion. Icteric forms of EBV infection are rare. In differential diagnosis of icterus caused by infectious agents, one should not forget EBV. .

[Reiter's syndrome after Salmonella infection]

Two patients with Reiter's syndrome, after Salmonella infection were treated on the Infections disease ward at Clinical hospital center in Kragujevac. In the first patient, ten days after the onset of Salmonella infection, signs of edema and pain in the right ankle occurred, accompanied by expressed conjunctivitis. Within next two months consecutive metatarsophalanges changes joint of the right foot have appeared. In the second patient, two weeks after the onset of Salmonella infection, edema of the left hand joints and a week later edema of the right hand and right ankle joints appeared. In both patients inflammatory syndrome was expressed (high erythrocyte sedimentation rates, fibrinogen, C-reactive protein) along with negative rheumatoid factors and positive antigen HLA-B27. Outcome of the disease in both cases was favourable upon receiving nonsteroid antirheumatic therapy. Signs of arthritis disappeared after three months. No signs of recurrent arthritis have been seen during the next four years in the first and next two years in the second patient.

[Risk factors for hepatitis C virus infection]

INTRODUCTION

Hepatitis C viral infection represents a major health problem in the world. The estimated global incidence is about 3%, whereas the number of chronic hepatitis C virus (HCV) carriers worldwide is estimated to be between 150-300 million people.

MATERIAL AND METHODS

This retrospective analysis included 82 patients whose diagnosis of viral hepatitis C infection was based upon the following criteria: case history, physical examination, laboratory and abdominal ultrasound examination, histological examination of the liver, radiological examination, serological analysis and viral analysis. Descriptive statistics were used to describe general data on patients of the study group, risk factor analysis and follow-up results.

RESULTS

The most prominent risk factor in our study group was intravenous use of drugs in 37 patients (37%), and blood transfusion in 13 patients (13%). Less important risk factors of viral hepatitis C infection included: promiscuity (8%), sexual contact with hepatitis C carriers (5%), surgical intervention (5%), hemodialysis (3%), intranasal use of cocaine (2%).

DISCUSSION

Hepatitis C viral infection has become the illness of young and middle-aged population. This is due to the epidemic profile of this illness, due to intravenous use of drugs as the most prominent risk factor.

CONCLUSION

Due to the number of infected, numerous risk factors and complications of viral hepatitis C, hepatitis C virus has become the most prominent hepatotrophic virus.

[Pseudomembranous colitis during antibiotic therapy]

INTRODUCTION

The use of antibiotics is commonly accompanied by diarrhea: idiopathic diarrhea with a benign process and diarrhea caused by Clostridium difficile and pseudomembranous colitis. Clostridium difficile colonizes the gastrointestinal tract and produces a toxin in cases when normal flora is suppressed by antibiotics. Pseudomembranous colitis most frequently appears after application of clindamycin, lincomycin, ampicillin, cephalosporins and other antibiotics. Diagnosis is established after rectoscopic findings of adherent pseudomembrane and pathohistological verification. The diagnosis is confirmed if there is evidence of Cl. difficile toxin in feces.

CASE REPORT

We report about the clinical course of two patients with antibiotic-associated colitis. The diagnosis were made by clinical examinations, rectoscopy and pathohistologic verification of biopsy specimen of the intestinal mucosa. Neutralization test was not done due to technical reasons. Patients were treated with metronidazole. Unwanted side-effects of metronidazole therapy were not observed.

DISCUSSION

Both our patients confirmed that they previously used different antibiotics. In the first case, diarrhea appeared during the antibiotic therapy, and in the second case, after finishing it. After antibiotic use, diarrhea appears in 5.30% cases, but fortunately pseudomembranous colitis is rare. However, taking into consideration that pseudomembranous colitis has a severe course and requires urgent treatment, one has to consider the possibility of pseudomembranous colitis when diarrhea appears during and after antibiotic use in order to initiate adequate therapy.