Normalne vrijednosti olova u krvi

In order to evaluate normal values of lead in blood for the local population of Zagreb and environs the concentrations of lead in blood have been determined in a random sample of 195 healthy subjects (100 men and 95 women with no previous exposure to lead. The analyses were performed by a monocolour dithizone method. Two parallel samples of blood were analysed for each subject. It was found that the lead concentrations in blood of normal persons are log-normally distributed. 60 µg/100 ml is proposed as the upper normal limit of lead concentration in blood.Radi određivanja normalnih vrijednosti olova u krvi izvršili smo analizu krvi kod 195 zdravih osoba (100 muškaraca i 95 žena) iz Zagreba i okolice, koji u svom zvanju nisu dosad bili eksponirani olovu. Analize smo izvršili jednobojnom ditizonskom metodom (Weber, Voloder, Vouk, Arh. hig. rada, 3 (1952) 296). U području od 10-500 µg Pb/100 ml krvi preciznost te metode iznosi od ± 4,6 µg do ± 5,6 µg (preračunano po 100 ml krvi). Taj se podatak odnosi na aritmetičku sredinu rezultata dviju paralelnih analiza istog uzorka. Za svakog ispitanika izvršili smo po dvije paralelne analize. Za pojedinu analizu potrebno je 5 mi krvi. Našli smo, da su koncentracije olova u krvi kod neeksponiranih osoba raspodijeljene logaritamski normalno. Kao gornju granicu normalnih vrijednosti uzeli smo gornju 90%-nu granicu tolerancije (koeficijent pouzdanosti 0.95). Tako definirane normalne vrijednosti iznose za ukupni uzorak 60 µg/100 ml. Našli smo također. da stanovnici sela imaju statistički značajno niže vrijednosti olova u krvi nego stanovnici grada, ali te razlike nemaju praktične vrijednosti za dijagnozu profesionalne ekspozicije olovu

Sinteza ciklopentandiamin -tetra octene kiseline, novog kelata za internu dekontaminaciju radiostroncija

La synthèse de l\u27acide cyclopentane-diamine-tétraacétique (1,2-CPDTA) est décrite. Les valeurs pour les constantes de dissociation protonique et pour les constantes de stabilité de ses complexes alcalino-terreux sont données. Le 1,2-CPDTA pourrait servir pour la décontamination interne du radiostrontium.Opisana je sinteza ciklopentandiamin-(1,2)-tetraoctene kiseline (1,2-CPDTA). Dane su vrijednosti za konstante disocijacije kao i za konstante stabilnosti kompleksa Ca+2 i Sr+2 s tom supstancijom. koja bi mogla poslužiti za internu dekontaminaciju 90Sr

Adaptation to muscular work after a long period rest

Sekrecija adrenokortikalnih hormona raste u početku adaptacije na mišićni rad, a zatim postepeno pada na normalnu vrijednost (1). Pokušali smo istražiti, da li ponovno izlaganje štakora istom stresoru nakon mjesec dana odmora izaziva iste promjene adrenokortikalne aktivnosti. Kao indikator koncentracije kortikoida u krvi uzeli smo broj eozinofilnih leukocita u perifernoj krvi, a za aktivnost kore nadbubrežne žlijezde razinu C vitamina u nadbubrežnoj žlijezdi.In albino rats previously adapted to muscular work the decrease in number of eosinophiles and ascorbic acid content of the adrenal gland after exercise is less pronounced than in control animals, even after a resting period of one month. According to the eosinophile cell reaction and ascorbic acid test, the animals thus seem to remain adapted to muscular work in spite of the long rest

The influence of lead ions on the release of acetylcholine

Iako o djelovanju olova na organizam postoje brojni podaci u literaturi (1), pitanje djelovanja olova na sinaptičku transmisiju nije još razjašnjeno. U ovom saopćenju iznosimo rezultate nekih eksperimenata, koji pokazuju, da slobodni ioni olova smanjuju lučenje acetilholina i utječu na sinaptičku transmisiju. Služili smo se metodom perfuzije gornjeg vratnog simpatičkog ganglija mačke (2). Perfuzija ganglija vrši se ezeniniziranom (1 : 100 000) Ringer-Lockeovom otopinom. Uz određene uvjete stimulacije preganglionarnog nervnog vlakna (frekvencija 2 sec-1, trajanje jednog impulsa 1 msec, suprarnaksimalna napetost) u trajanju od 5 minuta s prekidom od najmanje 5 minuta prije iduće stimulacije, uzorci perfuzata skupljeni za vrijeme stimulacije sadržavaju podjednake količine acetilholina (3). Kad smo perfuzionoj tekućini dodavali olovo u obliku nitrata (0,5 do 8,0 mikrograma/ml Pb++), znatno se smanjila količina izlučenog acetilholina, što je koncentracija olovnih iona bila veća, lučenje acetilholina bilo je slabije. Sl. 1 prikazuje rezultat eksperimenta, u kojem je perfuzionoj tekućini bilo doda no olovo u koncentraciji od 1,0 mikrogram/ml. Količina izlučenog acetilholina pala je nakon dodatka olova na 35% početne vrijednosti (Sl. 1, stupac 2.). Čini se, da je djelovanje olovnih iona samo djelomično reverzibilne, jer je i nakon uklanjanja olova iz perfuzione tekućine lučenje acetilholina još uvijek ostalo nešto smanjeno. Za vrijeme perfuzije ganglija registrirali smo i kontrakcije membrane niktitans. Sl. 2 prikazuje stepen blokade sinaptičke transmisije uz različite koncentracije olova u perfuzionoj tekućini. U lom smo eksperimentu postigli potpunu blokadu transmisije pri koncentraciji olova od 2 mikrograma/ml.To test the effect of lead ions upon the output of acetylcholine perfused preparations of cat\u27s superior cervical ganglion were used. The preganglionic nerve was stimulated with supramaximal shocks at a frequency of 2 per sec for 5 min. Addition of lead nitrate (1,0 microgram/ml) to the perfusion fluid (Ringer-Lockc\u27s solution containing 1 : 100 000 eser in sulphate) reduced the amount of acetylcholine in the perfusate to about 35% of its original value (Fig. 1). With higher concentrations of lead ions even less acetylcholine was released on preganglionic stimulation. The effects were only partly reversible. When nictitating membrane contractions were recorded addition of lead ions lo the perfusion fluid caused complete block of ganglionic transmission (in concentrations from 2.0 to 8,0 micrograms/ml) while stimulating the preganglionic nerve fibres (Fig. 2). The reaction of the nictitating membrane lo stimulation of postganglionic fibres stayed unaltered (Fig. 3). It may be supposed that lead ions have a similar influence on cholinergic nerve endings al the neuromuscular junction in spite of differences between these two structures

Coagulation activity of stored blood at +4°C

U ovom je radu ispitana koagulaciona aktivnost uskladištene krvi na +4°C. Primijenjeno je osam koagulacionih testova, a promjene koagulacione aktivnosti prikazane su grafički. Testiranje je izvršeno odmah nakon vađenja krvi, te drugi, sedmi i četrnaesti dan. Rezultati autora uspoređeni su s rezultatima iz literature.The coagulation activity of blood stored at 4°C was investigated. Eight different clotting tests were used. The changes in the coagulation activity are presented graphically. The testing was performed .immediately after the blood was taken from the vein and then after the first, seventh and forteenth day of storage. The authors compare their results with the data reported in literature. On each figure the time of storage in days is marked on the abscissa. The ordinate indicates the clotting time in sec. (Fig. 1), the prothrombin time in sec. (Fig. 2), the prothrombin consumption test in sec. (Fig. 3), the number of platelets x 10-3 (Fig. 4), the tromboplastin generation test, % activity (Fig. 5), the antihemophilic globulin % (Fig. 6), factor V activity % (Fig. 7), factor VII activity % (Fig. 8)

Pathways and bioenergetics of anaerobic carbon monoxide fermentation

Carbon monoxide can act as a substrate for different modes of fermentative anaerobic metabolism. The trait of utilizing CO is spread among a diverse group of microorganisms, including members of bacteria as well as archaea. Over the last decade this metabolism has gained interest due to the potential of converting CO-rich gas, such as synthesis gas, into bio-based products. Three main types of fermentative CO metabolism can be distinguished: hydrogenogenesis, methanogenesis, and acetogenesis, generating hydrogen, methane and acetate, respectively. Here, we review the current knowledge on these three variants of microbial CO metabolism with an emphasis on the potential enzymatic routes and bio-energetics involved.The authors involved were financially supported by an ERC grant (project 323009) and the Gravitation grant (project 024.002.002) of the Netherlands Ministry of Education, Culture and Science and the Netherlands Science Foundation (NWO)

Effect of sulfate on carbon monoxide conversion by a thermophilic syngas-fermenting culture dominated by a Desulfofundulus species

A syngas-degrading enrichment culture, culture T-Syn, was dominated by a bacterium closely related to Desulfofundulus australicus strain AB33T (98% 16S rRNA gene sequence identity). Culture T-Syn could convert high CO concentrations (from pCO 34 kPa to pCO 170 kPa), both in the absence and in the presence of sulfate as external electron acceptor. The products formed from CO conversion were H2 and acetate. With sulfate, a lower H2/acetate ratio was observed in the product profile, but CO conversion rates were similar to those in the absence of sulfate. The ability of D. australicus strain AB33T to use CO was also investigated. D. australicus strain AB33T uses up to 40% CO (pCO 68 kPa) with sulfate and up to 20% CO (pCO 34 kPa) without sulfate. Comparison of the metagenome-assembled genome (MAG) of the Desulfofundulus sp. from T-Syn culture with the genome of D. australicus strain AB33T revealed high similarity, with an ANI value of 99% and only 32 unique genes in the genome of the Desulfofundulus sp. T-Syn. So far, only Desulfotomaculum nigrificans strain CO-1-SRB had been described to grow with CO with and without sulfate. This work further shows the carboxydotrophic potential of Desulfofundulus genus for CO conversion, both in sulfate-rich and low-sulfate environments.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER307 000004) by the European Regional Development Fund under the scope of Norte 2020 – Programa Operacional Regional do Norte. The financial support from FCT and European Social Fund (POPH-QREN) through the grant PD/BD/128030/2016 given to AA and through the project INNOVsyn – Innovative strategies for syngas fermentation (POCI-01-0145-FEDER-031377) is gratefully acknowledged. Research of AS and DS was supported a Gravitation grant (024.002.002) of the Netherlands Ministry of Education, Culture and Science.info:eu-repo/semantics/publishedVersio

Study on the Refusal of Vaccination against COVID-19 in Romania

The refusal to be inoculated with the anti-COVID-19 vaccine by a part of the Romanian population becomes a barrier against controlling and stopping this particularly infectious virus. The rapid evolution of COVID-19 vaccines has created confusion regarding health and safety. Many Romanian citizens refuse vaccination because of fears generated by uncertainties based on information obtained from fake news. At the present moment, January 2022, Romania has one of the lowest vaccination rates in the European Union, below 45% of the total population. In our study, we want to identify the determining factors behind the refusal of vaccination, offering a sociological analysis that, we hope, will help to understand this phenomenon. The analysis revealed that 81% of the respondents trust the mandatory vaccines under the national scheme and 57.3% trust the optional ones other than the anti-COVID-19 vaccines (like Rotavirus, Hepatitis A and B, Influenza, Meningococcal, Pneumococcal, etc.) and have less confidence in the anti-COVID-19 vaccines. The study also reveals a very high percentage of respondents who trust fake news claims