Evidence for central histaminergic mechanism in foot shock aggression

The role of central histaminergic system in foot shock induced aggression was studied in mice. Histamine administered by intracerebral (IC) injection (25–200 g) produced a significant increase in fighting episodes in a dose dependent manner. It was observed that mepyramine (H₁ blocker) given intraperitoneally (IP) significantly increased and metiamide (H₂ blocker) given IC decreased significantly the fighting response. To determine the nature of receptors involved in histamine induced facilitation of aggressive behaviour, histamine was administered IC in mice pretreated with mepyramine or metiamide. Mepyramine pretreatment further increased the facilitatory effect of histamine while metiamide blocked the enhancement of aggressiveness by histamine. Combined pretreatment with metiamide and mepyramine decreased significantly the fighting counts which remained unaffected after histamine. Haloperidol did not block the enhancement of aggression by histamine or mepyramine. However, atropine pretreatment partially inhibited the histamine induced increase in the fighting counts. Results of pretreatment with metiamide and atropine were similar to those obtained with pretreatment of metiamide and mepyramine. Metiamide alone or in combination with atropine failed to affect the facilitatory effect of amphetamine on the foot-shockaggression. It is concluded that central histamine H₂ receptors have a facilitatory role and H₁ receptors an inhibitory role on aggressive behaviour in mice induced by foot-shock. Since histamine per se had a facilitatory effect on foot-shock induced aggression, the central H₂ receptors seem to dominate over the H₁ receptors.     

Microvascular decompression for trigeminal neuralgia: report of outcome in patients over 65 years of age

Microvascular decompression (MVD) is now recognized as an effective operation for the cure of trigeminal neuralgia (TN), and is far superior to the other surgical procedures utilized in the treatment of TN. TN is common in the elderly, but there is debate concerning MVD in 'elderly' patients. Some clinicians have a policy of not offering patients over a certain age the choice of MVD, yet the recurrence rate is inversely related to the age of the patient. Previous failed procedures and a long period of pain before MVD, also affect the outcome negatively. This study is a retrospective review of the outcome in elderly patients following MVD. Forty-two patients over the age of 65 years are reviewed after undergoing MVD for TN. The results indicate that there was no serious morbidity or mortality that could be ascribed to old age and the length of stay in the hospital was not influenced by the age of the patient. The results are compared with the outcome in a younger age group and the literature on MVD for TN reviewed.     

In vivo neutron dosimetry during high-energy Bremsstrahlung radiotherapy

Purpose: A new technique is presented for in vivo measurements of the dose equivalent from photoneutrons produced by high-energy radiotherapy accelerators.Methods and Materials: The dosimeters used for this purpose are vials of superheated halocarbon droplets suspended in a tissue-equivalent gel. Neutron interactions nucleate the formation of bubbles, which can be recorded through the volume of gel they displace from the detector vials into graduated pipettes. These detectors offer inherent photon discrimination, dose-equivalent response to neutrons, passive operation, and small sensitive size. An in vivo vaginal probe was fabricated containing one of these neutron detector vials and a photon-sensitive diode. Measurements were carried out in patients undergoing high-energy x-ray radiotherapy and were also repeated in-phantom, under similar irradiation geometries.Results and Conclusion: Neutron doses of 0.02 Sv were measured in correspondence to the cervix, 50 cm from the photon beam axis, following a complete treatment course of 46.5 Gy with an upper mantle field of 18-MV x-rays. This fraction of dose from neutrons is measured reliably within an intense photon background, making the technique a valid solution to challenging dosimetry problems such as the determination of fetal exposure in radiotherapy. These measurements can be easily carried out with tissue-equivalent phantoms, as our results indicate an excellent correlation between in vivo and in-phantom dosimetry.     

Analysis of COVID-19-associated rhino-orbital-cerebral mucormycosis patients in a tertiary care center in Northern India

Purpose:An unprecedented surge has been noted in rhino-orbital-Cerebral mucormycosis (ROCM) in times of current COVID-19 pandemic. The present prospective study aims to evaluate clinico-epidemiological profile, risk factors, management, and outcome of the cases of ROCM that presented to our tertiary care center during the study period from April to June 2021.Methods:All patients were subjected to complete history taking, ophthalmological examination, and imaging studies. The patients were staged and were treated with intravenous liposomal amphotericin B (AMB) and sino-nasal debridement of local necrotic tissue. Transcutaneous retrobulbar AMB (TRAMB), orbital decompression, and exenteration were instituted as indicated. All patients were followed up for a minimum of 6 months before arriving at the final outcome. Statistical analysis was performed.Results:A total of 49 patients presented during the study period, with a mean age of 42.2 years. The major risk factors included uncontrolled diabetes (89.8%), COVID-19 positivity (51.02%), and concurrent steroid use (38.77%). The most common presenting symptom was facial pain/swelling (43.65%), while the most common presenting sign was deterioration in vision (75.51%). Intravenous liposomal AMB was given to all patients along with sino-nasal debridement (85.71%), TRAMB (57.14%), orbital decompression (14.28%), and exenteration (12.24%). Overall, mortality at 6 months was 22.45% (11 patients). Age more than 60 years, intracranial extension, and HbA1c of more than 8.0% were observed to be statistically significant indicators of mortality.Conclusion:Early suspicion and timely diagnosis of mucormycosis at rhino-orbital stage is warranted in order to salvage life as well as visual function. TRAMB may prove as potentially favorable treatment modality in cases with limited orbital involvement.     

An unusual complication of Cloward's procedure presenting to the otolaryngologist

We present the case of a 51-year-old lady who developed a CSF leak following a Cloward's procedure (anterior cervical surgery with fusion), which settled with conservative management. Two months following the surgery she was assessed by an otolaryngologist for persistent dysphagia and a swelling in the anterior triangle of her neck. A computed tomography (CT) scan identified a fluid-filled mass displacing the trachea and communicating with the anterior cervical vertebrae, thus confirming the persistence of a CSF leak.     

Toxicological screening of traditional medicine Laghupatha (Cissampelos pareira) in experimental animals

Laghupatha (Cissampelos pareira) a important medicinal plant in Indian traditional system of medicine and is widely used in many countries by different tribal. Despite the wide use of Cissampelos pareira in folk medicine, no study has been published in the scientific literature about its toxicological profile. In present study 50% aqueous ethanolic extract of Cissampelos pareira (Menispermaceae) was evaluated for the acute and subacute toxicity. In the acute toxicity test, oral administration of 2g/kg of Cissampelos pareira produced neither mortality nor changes in behavior or any other physiological activities in mice. In subacute toxicity studies, no mortality was observed when the two doses of 1 or 2g/kg day of 50% aqueous ethanolic extract of Cissampelos pareira were administered p.o. for a period of 28 days in rats. There were no significant changes occurred in the blood chemistry analysis including glucose, sodium, potassium, calcium, phosphorus, chloride, total cholesterol, high density lipoprotein, triglycerides, total protein, blood urea nitrogen, creatinine, conjugated billirrubin, aspartate transaminase, alanine transaminase, total billirrubin, albumin, prothrombin time and thromboplastin partial time in both sexes of animals. Hematological analysis showed no marked differences in any of the parameters examined (WBC count, platelet and hemoglobin estimation) in either the control or treated group of both sexes. The urinalysis was negative for glucose, ketonic bodies, casts, red blood cells, and albumin in the control and treatment groups. There were no significant differences in the body and organ weights between controls and treated animals of both sexes. Pathologically, neither gross abnormalities nor histopathological changes were observed. Cissampelos pareira was found safe in acute and subacute toxicities while chronic toxicity studies are further required for the support of the safe and sound use of this traditional plant.     

The Technical Efficiency of Hospitals under a Single Payer System: The Case of Ontario Community Hospitals

Using DEA, we investigated the impact of ownership, size, and location on the relative technical efficiency of community hospitals in Ontario, which has a single payer system. Consistent with Hansmann's theory of non-profit organizations and contrary to US-based research, we find no significant differences in efficiency across ownership types (government, religious or secular non-profit). Nor do we find significant differences in efficiency by size or location. Our findings suggest that model formulation and differences in payer mix across types of hospitals in the US have a strong influence on the measurement of the hospital ownership–efficiency relationship.     

On the Morphological Deviation in Additive Manufacturing of Porous Ti6Al4V Scaffold: A Design Consideration

Additively manufactured Ti scaffolds have been used for bone replacement and orthopaedic applications. In these applications, both morphological and mechanical properties are important for their in vivo performance. Additively manufactured Ti6Al4V triply periodic minimal surface (TPMS) scaffolds with diamond and gyroid structures are known to have high stiffness and high osseointegration properties, respectively. However, morphological deviations between the as-designed and as-built types of these scaffolds have not been studied before. In this study, the morphological and mechanical properties of diamond and gyroid scaffolds at macro and microscales were examined. The results demonstrated that the mean printed strut thickness was greater than the designed target value. For diamond scaffolds, the deviation increased from 7.5 μm (2.5% excess) for vertical struts to 105.4 μm (35.1% excess) for horizontal struts. For the gyroid design, the corresponding deviations were larger, ranging from 12.6 μm (4.2% excess) to 198.6 μm (66.2% excess). The mean printed pore size was less than the designed target value. For diamonds, the deviation of the mean pore size from the designed value increased from 33.1 μm (−3.0% excess) for vertical struts to 92.8 μm (−8.4% excess) for horizontal struts. The corresponding deviation for gyroids was larger, ranging from 23.8 μm (−3.0% excess) to 168.7 μm (−21.1% excess). Compressive Young’s modulus of the bulk sample, gyroid and diamond scaffolds was calculated to be 35.8 GPa, 6.81 GPa and 7.59 GPa, respectively, via the global compression method. The corresponding yield strength of the samples was measured to be 1012, 108 and 134 MPa. Average microhardness and Young’s modulus from α and β phases of Ti6Al4V from scaffold struts were calculated to be 4.1 GPa and 131 GPa, respectively. The extracted morphology and mechanical properties in this study could help understand the deviation between the as-design and as-built matrices, which could help develop a design compensation strategy before the fabrication of the scaffolds.     

A Current Review of Cypermethrin-Induced Neurotoxicity and Nigrostriatal Dopaminergic Neurodegeneration

Cypermethrin, a class II pyrethroid pesticide, is used to control insects in the household and agricultural fields. Despite beneficial roles, its uncontrolled and repetitive applications lead to unintended effects in non-target organisms. Cypermethrin crosses the blood-brain barrier and induces neurotoxicity and motor deficits. Cypermethrin prolongs the opening of sodium channel, a major site of its action, leading to hyper-excitation of the central nervous system. In addition to sodium channel, cypermethrin modulates chloride, voltage-gated calcium and potassium channels, alters the activity of glutamate and acetylcholine receptors and adenosine triphosphatases and induces DNA damage and oxidative stress in the neuronal cells. Cypermethrin also modulates the level of neurotransmitters, including gamma-aminobutyric acid and dopamine. It is one of the most commonly used pesticides in neurotoxicology research not only because of its variable responses depending upon the doses, time and routes of exposure and strain, age, gender and species of animals used across multiple studies but also owing to its ability to induce the nigrostriatal dopaminergic neurodegeneration. This article describes the effect of acute, chronic, developmental and adulthood exposures to cypermethrin in experimental animals. The article sheds light on cypermethrin-induced changes in the central nervous system, including its contribution in the onset of specific features, which are associated with the nigrostriatal dopaminergic neurodegeneration. Resemblances and dissimilarities of cypermethrin-induced nigrostriatal dopaminergic neurodegeneration with sporadic and chemicals-induced disease models along with its advantages and pitfalls are also discussed.