Mass spectrometric analysis of Odonthobuthus Doriae scorpion venom and its non-neutralized fractions after interaction with commercial antivenom.

It is believed that antivenoms play a crucial role in neutralizing venoms. However, uncontrolled clinical effects appear in patients stung by scorpions after the injection of antivenom. In this research, non-neutralized components of the venom of the Iranian scorpion Odonthobuthus doriae were analyzed after interacting with the commercial antivenom available in the market. The venom and antivenom interaction was performed, then centrifuged, and the supernatant was analyzed by high-performance liquid chromatography (HPLC). Two peaks of Odonthobuthus doriae venom were observed in the chromatogram of the supernatant. Two components were isolated by HPLC and analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) instruments. Peptide sequencing was done by Liquid Chromatography Quadrupole Time-of-Flight Tandem Mass Spectrometry (LC-Q-TOF MS/MS). Results indicate that the components of scorpion venom mainly have a molecular weight below 10 kDa, consisting of toxic peptides that disrupt the function of sodium and potassium channels. The MALDI-TOF MS results show that two toxic peptides with molecular masses of 6941 Da and 6396 Da were not neutralized by the antivenom. According to the MS/MS sequencing data, the components have been related to peptides A0A5P8U2Q6_MESEU and A0A0U4FP89_ODODO, which belong to the sodium and potassium channels toxins family, respectively.

Evaluation of venom diversity and antivenom quality from the venom of long-term captive vs recently wild captured Pseudocerastes persicus snake: An In vitro and In vivo study.

Snakebite envenomation is a life-threatening condition and antivenoms are used as the most effective treatment. Venom obtained from snakes in long-term captivity showed some variations in comparison to the venom of the wild snakes. The objective of this study is to compare the venom of the Pseudocerastes persicus under long-term captivity and wild conditions as well as the antivenom obtained from these venoms. We have analyzed venom samples and produced trivalent antivenoms using the venom of long-term captive (LTC) or recently wild-captured (RWC) Pseudocerastes persicus, and RWC Macrovipera lebetina, and Echis carinatus. The HPLC analysis revealed that the RWC snakes' venom had three peaks that were not present in the LTC snake's venom. Further analysis using MALDI-TOF and MS/MS showed that the fraction with a retention time (RT) of 14 min contained a toxin from the Kunitz-type serine protease inhibitor (KUT) class, while the fraction with RT 21 a peptide identified within the snake venom metalloproteinase (SVMP) class. The third peak was identified as a sphingolipid. Interestingly, the in vivo preclinical tests showed no significant differences in the effectiveness of the antivenoms. which could be due to the cross-immunogenicity or cross-reactivity between different toxins in the venom. According to our results, small variations in the venom composition of a species do not lead to a decrease in the efficacy of the polyvalent antivenom.

Methotrexate as a safe immunosuppressive agent during the COVID-19 pandemic.

BACKGROUND: During the ongoing COVID-19 pandemic, immunocompromised patients are at a higher risk of severe infection, since the immune system has an important role in defeating this disease. This study compares the severity of COVID-19 in patients taking methotrexate with the severity of their family members' illness as patients with normal immune system function. METHODS: A total of 35 participants, including 14 patients taking methotrexate and 21 patients with normal immune function, entered this study, and the indicators of COVID-19 severity were compared between these two groups. RESULTS: The case group, who were on methotrexate therapy, had significantly less severe COVID-19 based on their symptoms, including fever (p = 0.000) and cough and dyspnea (p = 0.01) as well as in terms of COVID-19 severity indicators such as pulmonary involvement (p = 0.001), ferritin level (p = 0.001), white blood cell count (p = 0.008) and CRP level (p = 0.006), compared to the control group. There was a significant correlation between taking methotrexate and lower severity in COVID-19 disease. CONCLUSION: The present findings demonstrated that methotrexate does not predispose patients to severe COVID-19; on the contrary, patients taking methotrexate may experience a milder disease, possibly due to their reduced severe inflammatory reactions as a result of inhibited TNFα, lowered IL6, and increased T regulatory cells. According to these findings, methotrexate appears to be a suitable treatment option for patients who need immunosuppressive medications during the COVID-19 pandemic.

A case report of toxic leukoencephalopathy induced by metronidazole in a woman with surgical site infection.

Metronidazole may rarely cause encephalopathy and neuropathy. In this study, we report a 30-year-old post-partum, ex-addicted female with leukoencephalopathy due to metronidazole.

A case report of hydroxychloroquine-induced auditory and visual hallucination.

INTRODUCTION: Discoid lupus erythematosus (DLE) is a common manifestation of lupus erythematosus. Hydroxychloroquine is commonly used in the treatment of lupus erythematosus. The present study aims to report hallucinations induced by hydroxychloroquine. CASE PRESENTATION: A 37-year-old woman came to the dermatology clinic with a complaint of a red lesion on her left cheek. Physical examination revealed an ulcerative erythematous plaque with keratotic scales, an atrophic area of ~ 2 × 2.5 cm. Biopsy of the lesion was performed, and histopathology result was consistent with the diagnosis of DLE. Laboratory tests were all normal. Topical clobetasol and pimecrolimus were prescribed for the patient, who was recommended to use sunscreen as well. However, the treatment did not work, thus hydroxychloroquine 200 mg daily was added to the treatment. After a week, the patient came back to the clinic with her husband with the complaint of auditory and visual hallucinations, nightmares, and occasional decrease in consciousness level. After neurology and psychiatric consultation, hydroxychloroquine was discontinued and replaced with intralesional administration of triamcinolone. The lesion disappeared and did not recur. DISCUSSION: Previous studies and the lack of another explanation for the patient's hallucinations imply a strong correlation between hydroxychloroquine and hallucinations. The mechanism of these side effects has not been fully elucidated. However, this side effect has only been reported in cases of connective tissue diseases. As currently hydroxychloroquine is widely used in the treatment of COVID-19 and other diseases, its potential risk of psychiatric complications should be considered in clinical practice.

A rare case of fenpyroximate poisoning with presenting anticholinesterase poisoning signs.

We report a case of fenpyroximate poisoning with cholinergic signs that could be due to mixing it with anticholinesterase. Clinicians should consider co-ingestion of pesticides to proper diagnosis and management of the pesticide poisoning.

Monitoring and risk assessment of tetracycline residues in foods of animal origin.

A total of 450 samples consisting of red meat, poultry meat, aquatic product and raw milk were collected during winter 2016 and summer 2017. 22.2% (100/450) of collected meat and raw milk samples were found to be contaminated with antibiotic residues in the initial screening using Premi®test. According to the enzyme linked immunosorbent assay (ELISA) results, the mean tetracyclines (TCs) concentration of meat samples determined as follows: chicken (155.41 µg/kg) > turkey (138.68 µg/kg) > quail (130.7 µg/kg) > cow (108.92 µg/kg) > calf (105.18 µg/kg) > goat (99.4 µg/kg) > sheep (95.22 µg/kg) > rainbow trout (35.62 µg/kg) > shrimp (31.80 µg/kg). The content of TCs in cow, goat and sheep milk samples were found to be ranged 45.6-163.5 µg/L, 72.4-101.1 µg/L and 65.5-98.9 µg/L, respectively. 5.7% (26/450) of samples had TCs confirmed the ELISA results using high performance liquid chromatography coupled with ultra-violet detection, although the concentration of TCs residues in samples was higher than that of ELISA.