Decreased Plasma Levels of Kynurenine and Kynurenic Acid in Previously Treated and First-Episode Antipsychotic-Naive Schizophrenia Patients

Tryptophan (TRP) catabolites exert neuroactive effects, with the plethora of evidence suggesting that kynurenic acid (KYNA), a catabolite of the kynurenine pathway (KP), acts as the regulator of glutamate and acetylcholine in the brain, contributing to the schizophrenia pathophysiology. Newer evidence regarding measures of KP metabolites in the blood of schizophrenia patients and from the central nervous system suggest that blood levels of these metabolites by no means could reflect pathological changes of TRP degradation in the brain. The aim of this study was to investigate plasma concentrations of TRP, kynurenine (KYN) and KYNA at the acute phase and remission of schizophrenia in a prospective, case-control study of highly selected and matched schizophrenia patients and healthy individuals. Our study revealed significantly decreased KYN and KYNA in schizophrenia patients (p < 0.001), irrespective of illness state, type of antipsychotic treatment, number of episodes or illness duration and no differences in the KYN/TRP ratio between schizophrenia patients and healthy individuals. These findings could be interpreted as indices that kynurenine pathway might not be dysregulated in the periphery and that other factors contribute to observed disturbances in concentrations, but as our study had certain limitations, we cannot draw definite conclusions. Further studies, especially those exploring other body compartments that participate in kynurenine pathway, are needed.

Health care access of thyroid disease patients in Serbia during the COVID-19 pandemic

PURPOSE

The aim of this study was to assess the impact of repurposing health care facilities in response to COVID-19 on the access of patients with thyroid disease to health care.

METHODS

This study consisted of a web-based survey. The survey was anonymous and consisted of forty questions.

RESULTS

This survey included 206 respondents. 91.3% of the respondents had health insurance through the Republic Fund of Health Insurance, 9.7% had private or both health insurances, and 3.4% did not have any health insurance. A significant proportion of respondents (60.4%) had to switch from public to private health care to reach a physician and 73.8% had to switch from public to private laboratories. For the 91.9%, this was perceived as a financial burden. Before the pandemic, 83.1% of respondents reported regular follow-up by physicians, which decreased to 44.9% during the pandemic (p < 0.01). 76.3% of the respondents regarded that their thyroid disease was managed optimally before the pandemic, while this figure declined to only 48% during the pandemic (p < 0.01).

CONCLUSIONS

The COVID-19 pandemic disrupted the medical care of thyroid patients in Serbia. For the patients treated in the public health care system, access to general practice was hindered, while access to specialist care was disrupted. It led to a switch from public to private health care, which was perceived as a financial burden for almost all the respondents. However, private health care proved to be an important safety net when the public system was overwhelmed.

A novel human glycoprotein ACA is an upstream regulator of human hematopoiesis

A central issue in stem cell biology is a better understanding of the molecular mechanisms that regulate self-renewal of human hematopoietic stem cells (HSCs). Control of the specific function of HSCs like self-renewal and differentiation might be regulated by a common set of critical genes. However, the regulation among these genes is yet to be elucidated. Here, we show that activation by a novel human GPI-linked glycoprotein ACA at the surface of human peripheral blood progenitor cells induces via PI3K/Akt/mTor/PTEN upregulation of WNT, Notch1, Bmi-1 and HoxB4 genes thus, promoting self-renewal and generation of primitive HSCs. ACA-generated self-renewing cells retained their lympho-myeloid repopulating potential in NOD/SCID mouse xeno-transplantation model with long term functional capacity. We conclude that ACA is an essential regulator of the genes involved in maintaining hematopoiesis and its use in clinical praxis could overcome many of the barriers present so far in transplantation medicine.

Activation by ACA induces pluripotency in human blood progenitor cells

Reprogramming of human somatic cells by transcription factors to pluripotent state holds great promise for regenerative medicine. However, low efficiencies of current reprogramming methods, immunogenicity and lack of understanding regarding the molecular mechanisms responsible for their generation, limits their utilization and raises questions regarding safety for therapeutic application. Here we report that ACA signaling via PI3K/Akt/mTor induces sustained de-differentiation of human blood progenitor cells leading to generation of ACA pluripotent stem cells. Blood-derived pluripotent stem cells differentiate in vitro into cell types of all three germ layers, exhibiting neuronal, liver, or endothelial characteristics. Our results reveal insight into the molecular events regulating cellular reprogramming and also indicate that pluripotency might be controlled in vivo through binding of a natural ligand(s) to ACA receptor enabling reprogramming through defined pathway(s) and providing a safe and efficient method for generation of pluripotent stem cells which could be a breakthrough in human therapeutics.

[Cholecystitis associated with milk of calcium] ]

Milk of calcium cholecystitis is a rare disease predominantely of adults. The term designates a pathologic accumulation of calcium carbonate in the gallbladder, much rarer in the common bile duct as well. The patient may be symptom-free. If present the symptoms may be very mild or as an acute biliary pain, transient jaundice and mild attack of pancreatitis. Calcium in the bile may be liquid or it may form a paste-like mass. Both may be seen on a plain X-ray of the abdomen. The stone or stones of calcium carbonate may be formed so that they may cause an obstruction of the gallbladder outflow tract or cystic duct or pass into the common bile duct or into the duodenum. [figure: see text] We present a 71 year old male who was admitted for inguinal hernia repair but in whom a mild hiperbilirubinaemia was found and then on ultrasonography a gallbladder stone was diagnosed. We performed a hernia repair as well as cholecystectomy and operative cholangiography which turn to be normal. Within an almost normal gallbladder a gray-whitesh paste-like mass was found composed of calcium carbonate. The postoperative recovery was uneventful and serum bilirubin become normal. Histology of gallbladder showed chronic nonspecific cholecystitis.

Adenomyoma of the common hepatic duct

BACKGROUND

Adenomyoma occurs most commonly in the fundus of the gallbladder, seldom in other parts of the gallbladder and rarely in the extrahepatic biliary tree, where most lesions are localised to the common bile duct or papilla of Vater. Adenomyoma of the common hepatic duct is extremely rare. To the best of our knowledge, only three cases have been reported so far.

CASE OUTLINE

A 51-year-old woman was admitted with a three month history of attacks of right upper abdominal pain, nausea, vomiting and fever. Laboratory data, ultrasonography, ERCP and CT confirmed slight cholestasis and proximal bile duct dilatation due to a tumour within the common hepatic duct. Cholecystectomy was performed with excision of the suprapancreatic common bile duct including the convergence of the hepatic ducts plus lymphadenectomy and Roux-en-Y hepaticojejunostomy. Frozen section histology showed the benign nature of the lesion and a tumour-free resection line. Final histology showed adenomyoma. The patient has remained symptom free for more than 30 months.

DISCUSSION

Although adenomyoma is a benign lesion and the surgical strategy has not been established, complete excision with frozen section is recommended to exclude small malignant foci and local recurrence as well as to avoid surgical over-treatment.

[A retroperitoneal bronchogenic cyst]

Bronchogenic cyst is a rare congenital (developmental) anomaly. It is usually asymptomatic but its enlargement and localization may cause serious symptoms. Exact preoperative diagnosis is rarely established. As a rule, it is established during histological examination of the resected specimen. We present a patient with a subdiaphragmatic retroperitoneal bronchogenic cyst in whom exact diagnosis was documented by histological examination of excised cyst. To our knowledge this is the third such case ever reported.

[Retropancreatic hematoma mimicking a tumor in a female patient with liver amyloidosis]

Bleeding in patients with amyloidosis is considered as a frequent complication appearing in up to 40% of cases. It may be spontaneous or provoked. Spontaneous bleeding in the skin or in the gastrointestinal tract is the most frequent. Spontaneous bleeding in the retroperitoneum is rare. It may be diffuse, with possible lethal outcome, or localised, causing haematoma, as in our patient. We present a 62-year old woman with a three-month history of spontaneous, subcutaneous bleeding. No laboratory or other findings could explain the cause of bleeding, as the haemostatic tests were within or close to normal limits. US and CT performed for right subcostal pain discovered a tumour attached to the back of the head of pancreas. Due to mild coaugated hyperbilirubinaemia the "tumour" was held to be the cause of patient's difficulties. However, at operation it turned out to be a retropancreatic haematoma, which was removed and drained. Because of conjugated hyperbilirubinaemia cholecystectomy with operative cholangiography (which was normal) were performed. Due to steatotic appearance of the liver a biopsy was performed. Histological examination revealed amyloidosis. The recovery was uneventful and the patient was transferred to hepatology unit for further treatment where she died 3 months later due to gradual deterioration of kidney and heart function. To our knowledge, retroperitoneal haematoma in liver amyloidosis mimicking retropancreatic tumour has not been reported so far.

[Solid and cystic-papillary tumor of the pancreas]

Solid and cystic-papillary tumour of the pancreas is a rare neoplasm. About 420 cases seem to have been reported as yet. It appears almost exclusively in young women, although it may appear in males in all ages. This is a tumour of benign or low malignant potential with vary rare invasion of surrounding tissues and organs. Metastases of the tumour are rare. Local recurrence after surgical excision is also rare. About 50% of patients have no symptoms. The others may have upper abdominal pain or palpable abdominal mass. Complications such as rupture, bleeding or secondary infection, are rare. The average size of the tumour is cca 10 cm in diameter. The tumour is more frequent in the body and tail of the pancreas. New imaging techniques make diagnosis of the tumour very easy, but exact diagnosis is based on histological findings. Surgical excision is the treatment of choice. We report on a 23-year-old woman with a two-year history of upper abdominal pain and occasional fever, in whom ultrasonographic and CT scan examinations revealed a well defined mass of 5 cm in diameter. The mass was excised with limited resection of the pancreas along with removal of the spleen which was adherent to the mass so that it could not have been saved. Histological findings established a solid and cystic-papillary neoplasm of the pancreas. The recovery was uneventful. The patient was symptom-free, with normal clinical findings and laboratory results.

[Hamartoma of the spleen]

Hamartoma is a rare benign lesion of the spleen. Between 140 and 150 cases seem to have been described so far. Hamartoma of the spleen may appear as a single or multiple lesions which may tend to converge. It appears in all ages, mainly in elderly persons. About 20% of patients were described in paediatric subjects. Half of the patients have no symptoms, so that hamartomas were discovered by chance at autopsy. Other 50% of patients had pain, splenomegaly, haematologic abnormalities (most frequently thrombocytopenia or pancytopenia) and spontaneous rupture with intra-abdominal bleeding. In children, hamartoma of the spleen with haematologic abnormalities may be followed by growth retardation, frequent infections, fever and night sweating. The bigger the hamartoma the greater probability to cause symptoms. The exact preoperative diagnosis is rarely established. Hamartoma has to be taken into account always when tumour of the spleen is diagnosed, particularly in children. Splenectomy is the most frequent treatment of symptomatic hamartoma of the spleen. Partial splenic resection is the preferred surgery whenever it may be carried out, particularly in children. We report a 58 year old woman with a five-year history of left subcostal and lumbar pain in whom in the lower pole of moderately enlarged spleen a tumorous mass, 107 x 75 mm in diameter, was discovered on ultrasonography. She was submitted to splenectomy as well as to cholecystectomy due to gall bladder stones. Histological findings of the spleen showed hamartoma. She had an uneventful recovery. The pain disappeared after surgery. She stayed symptom free so far.

[Giant epithelioid leiomyosarcoma of the stomach]

Epithelioid leiomyosarcoma of the stomach is an uncommon tumour, predominantly in old persons. The majority of tumours are small, giant tumours are rare. A tumour is more frequent in the upper part of the stomach. It rarely gives secondary deposits, almost only large ones. In a few big published series of patients, secondary deposit were not found in lymph nodes or other organs. Gastrointestinal bleeding, easy fatigue and pain are the usual symptoms of the disease. Endoscopic and fine needle biopsy was successful in single cases. A limited wedge gastric resection is considered as one of the most appropriate surgical treatments. Major resections are reserved for giant tumours infiltrating surrounding organs, and for recurrencies. Due to rare involvement of lymph nodes, systematic lymph node dissection is not regarded as a necessary procedure. The recurrencies can be successfully removed in a number of cases. Chemo- and radiotherapy are generally regarded as useless. We present a 61-year old male patient who had discomfort in the upper abdomen. CT scan was performed but radiologist missed to diagnose an obvious mass in the upper mid-abdomen. Three years later he came with high temperature and leukocytosis. The preoperative examination showed conflicting results, ultrasonography that the tumour did not belong to the liver but CT scan showed that the tumour arose from the left lobe of the liver. Barium swallow showed signs of external pressure on the stomach from the right toward left and downwards. During the operation, a giant gastric tumour (215 x 139 x 135 mm) originating in the antral part of the small gastric curvature was removed with distal 2/3 of the stomach. Histologic examination showed epithelioid leiomyosarcoma of the stomach with umbilical ulceration. About 50% of the tumour was necrotic. There were no lymph node deposits. Temperature and WBC count dropped to the normal value soon after surgery. The patient stayed symptom-free so far, five months after the operation.

Activities of antioxidant enzymes and formation of the glutathione adduct of hemoglobin (Hb ASSG) in epileptic patients with long-term antiepileptic therapy

The activities of antioxidant enzymes (AOE) and amounts of glutathione adduct of Hb (Hb ASSG) in erythrocytes of chronic epileptic patients treated with mono or mixed therapy of phenobarbital (PB), carbamazepin (CBZ) and valproic acid (VPA), were evaluated and the results were compared with those for normal individuals. The activity of superoxide dismutase (SOD) was lowered for 40% to 60% in epileptic patients relative to normal controls. The lowest activity of SOD was found in patients treated with CBZ and PB. Activity of glutathione peroxidase (GSH-Px) was lowered comparing to the control from cca 15% in patients treated with PB to 50% in those treated with either CBZ alone or with CBZ in combination with PB. For the later two sub-groups of patients significantly lowered activities of catalase and glutathione reductase (cca 20% and 30-40%, respectively) were also characteristic. The highest amounts of Hb ASSG (cca 4% of the tota lHb) were found in hemolysates of patients with the lowest AOE levels i.e., in those treated with CBZ alone or with CBZ in combination with PB. In hemolysates of patients treated with PB, Hb ASSG represented 2.4% of the total Hb, while it was totally absent in those treated with VPA, although SOD and GSH-Px levels in erythrocytes of both of these sub-groups of patients were lowered to the same extent.

Rat pancreatic B-cells after chronic alcohol feeding. A morphometric and fine structural study

Quantitative analysis of the light microscopic and fine structure of rat islet B-cells was carried out in chronic alcoholism. Absolute pancreatic weight and volume were similar in groups C (control) and E (ethanol), but relative pancreatic weight in group E rat was decreased. The results for fasting blood glucose and insulin levels were similar in the two groups of animals. There was a significantly reduced total pancreatic islet volume in E rats. The total number of endocrine cells both per islet and per microns2 of islet was similar in the two groups of animals. The volume density and number of B-cells per islet and per microns2 of islet were not changed in ethanol-treated rats as compared with the control. On the other hand, diameter, surface area and volume of the B-cells and their nuclei were found to be statistically significantly decreased. Histological examination revealed that islet blood vessels were dilated in alcoholic rats. Over the 4-month period of ethanol intake a significant decrease in cell profile area, nuclear profile area and volume density of cytoplasmic granules and an increase in the profile area and volume density of endoplasmic reticulum occurred. The gross histological alteration seen in most B-cells of the ethanol-treated rats was irregularity of the nuclear envelope with deep invagination and with margination of heterochromatin and many empty granules or granules without clear electron dense crystals of insulin. The present results indicate some optical and structural abnormalities of B-cells in chronic alcoholism that may be related to cell dysfunction and may contribute, at least in part, to the endocrine pancreas functional disturbance.

Glutathione adduct of hemoglobin (Hb ASSG) in hemolysates of patients on long-term antiepileptic therapy

1. A novel, hitherto unrecognized, hemoglobin fraction, HbA1x, has been detected in amounts up to 7% of the total Hb, in hemolysates from epileptic patients with long-term therapy containing phenobarbital (PB) and carbamazepine (Carb). 2. HbA1x was shown to represent glutathione adduct of Hb (Hb ASSG). 3. To our knowledge, this is the first demonstration of the occurrence of Hb ASSG in vivo.

Thymic microenvironment in myasthenia gravis

This study was undertaken to investigate the role of thymic epithelial (TE) cells in the immunopathology of myasthenia gravis (MG). Seventeen thymuses from patients with MG and six normal thymuses were investigated by light and electron microscopy, using a stereologic method. In the myasthenic thymuses the cortex was markedly reduced, while the medulla was hypertrophied and had numerous germinal centers. A subpopulation of cortical TE cells showed a large fibrillar nucleolus and a decreased number of cytoplasmic dense bodies and cysts, indicating decreased function. Medullary TE cells, on the other hand, showed evidence of increased activity with an enlarged euchromatic nucleus and an increased number of cytoplasmic dense bodies. There was a statistically significant negative correlation between the decrease in size of the thymic cortex and the appearance of medullary germinal centers. A significant correlation was also demonstrated between atrophy of cortical TE cells and depletion of cortical thymocytes. Our study shows that both cortical and medullary TE cells are involved in the pathogenesis of MG but have different roles.

A study of the health status of radar workers

The health status was examined of 322 radar workers with a history of occupational exposure in a microwave field from 5-10 years. The clinical findings were compared with a control group of 220 persons. There were no statistically significant differences in clinical and laboratory findings between exposed and control group. Only some subjective complaints were found more frequently in the exposed group than in the control. The authors' feeling is that subjective complaints in radar workers could not be ascribed only to the influence of microwaves because they could be due to other nonspecific harmful occupational factors. On the basis of the results of this work, the authors concluded that it is unlikely to expect marked harmful effects from microwaves in radar workers in normal working conditions.