RABIES ORAL IMMUNIZATION AGAINST RABIES

1998 ◽  
Vol 22 (1) ◽  
pp. 175-184
Author(s):  
Khalid A. Hussain

Rabies is a highly fatal infection of the central nervous system which occur in all warm-blooded animals and transmitted by the bites of affected animals. The major manifestations of the disease include motor irritation and clinical signs of mania and an attack complex and ascending paralysis. Rabies and rabies related viruses belong to a group of more than 75 viruses called RHABDOVIRUSES (Rhabdo=rod) because of their bullet-shaped morphology. The virus is fragile, easily inactivated by disinfectants, and does not exist free in the environment. Instead, in the course of its infection in reservoir host species, it is shed into the saliva and is transmitted by bite. After entry into a new host in the bite site, rabies virus multiplies in muscle cells and aggregates around the proprio receptor nerve endings of their acetylcholine receptors and then spreads through neural pathways, all without stimulating an effective host immune response. Transmission depends on simultaneous delivery of virus to the salivary glands and the limbic system of the brain. Infection of the limbic system of the brain is the cause of the fury which drives the animal to bite. Infection of the salivary glands is the source of the large amounts of virus in saliva. This unique pathogenetic patterns leads to entrenchment of the virus in its reservoir host populations and to continuing risk of exposure of man. Dog rabies has been controlled globally by the use of potent vaccines and the application of effective urban control programs (poisoning trapping shooting). The problem that then remained has been wildlife rabies, primarily in wolves, foxes, skunks, raccoons as well as stray dogs. Therefore, a new approach to wildlife rabies control has been made which involves oral vaccination. Several successful trials were attempted in Switzerland, West Germany and the U.S.S.R. Rabies control efforts in the developing countries did little to really reduce the incidence of the disease. Therefore, mass vaccination of dogs and the elimination of strays coupled with the oral vaccination (recombinant vaccinia vaccine) of dogs so that the population of susceptible stray dogs can be immunized. 

Author(s):  
Robert Dantzer ◽  
Keith W. Kelley

Mind-body literature, in the form of magazines and self-help books on stress and healing, is full of definitive claims for the existence of powerful influences of emotions and psychosocial stressors on the immune system, leading to onset or progression of cancers or infectious diseases. This literature often makes explicit reference to research in psychoneuroimmunology to support these claims. Psychoneuroimmunology is a multi-disciplinary field that has grown rapidly during the last three decades at the crossroads of immunology, behavioural neurosciences, neuroendocrinology, and psychology. It studies mechanisms and functional aspects of bidirectional relationships between the brain and the immune system. Although still controversial, there is evidence that psychological events including emotions can and do influence the outcome of infectious, autoimmune, and neoplastic diseases via modulation of cells of the immune system. A surprising finding has been that immune events occurring in the periphery also affect mood, behaviour, and metabolism by modulating brain functions, thereby providing a biologically important link between the immune system and brain. The original discovery that activation of the innate immune system in the periphery causes clinical signs of sickness that are processed in the brain is now being extended to the involvement of the immune system in depressive disorders. This new information has solidified the idea that neurotransmitters, neuropeptides, neural pathways, and immune-derived signals such as cytokines are the minimal essential elements that permit the immune system and brain to communicate with one another. These new data offer the unexpected conclusion that the immune system is likely to be involved in not only how emotions affect health but also how immune events regulate the development and expression of emotions.


2009 ◽  
Vol 59 (1) ◽  
pp. 55-65 ◽  
Author(s):  
Koenraad Kortmulder ◽  
Jacob Dubbeldam

AbstractA category of teder interaction is proposed as the main source of (mutual) mild touch stimuli in higher vertebrates. The somatosensory circuits for the perception of these stimuli in mammals and birds are discussed using data from the literature. In addition to the usual somatosensory areas of the brain, in mammals mild touch signals are also conducted to the insula, which is closely connected to the limbic system. This separate processing of mild touch stimuli lends more substance to the category of teder behaviour. The comparable neuroanatomy in birds is more difficult to interpret. There are some intriguing parallels between the relevant circuits of mammals and birds, though in the telencephalic parts in particular, conclusions are limited by uncertainties as to the homologies of the mammalian and avian brains.


Author(s):  
M. A. Hossen

Background: Leishmaniasis is primarily caused by two species of Leishmania (L. donovani and L. infantum) of which clinical infection with L. infantum has been recognized in both humans and dogs as zoonotic disease with dogs as the main reservoir hosts in the Mediterranean, the Middle East, Asia and South America. Although L. donovani has been associated with both clinical and asymptomatic infection in humans but it is still associated with asymptomatic infection in dogs in Indian sub-continent without any evidence of zoonotic infection. Objectives: The objective of this research was to investigate the potentiality of dog as reservoir host for visceral leishmaniasis in the human leishmaniasis endemic regions in Bangladesh. Materials and Methods: A total of 20 stray dogs in the human VL endemic areas of Mymensingh district were captured for the detection VL during the period of November 2010 to May 2011. The dipstick test rK39 (Bios International; n = 20), Giemsa’s stained impression smears of liver and spleen (n = 6) and PCR with the tissue of liver and spleen (n = 6) were tested as per manufacturer instructions and conventional standard methods. Results: Out of 20 stray dogs examined, 4 (20.0%) were positive for L. donovani infection with rK39 strip test. Of the six randomly selected dogs tested with Modified Giemsa’s stained of impression smears of spleen and liver showed 2 (33.33%) positive whereas PCR technique detected 5 (83.33%) positive for L. donovani. Results of PCR showed 145bp amplicon, specific for L. donovani infection in 83.33% stray dogs. Conclusions: This study reveals that a high percentage of L. donovani asymptomatic carrier infections occur in dogs and evidence indicates that dogs and humans may potentially serve as a source of infection to sand fly vectors and accordingly dogs can be recognized as a probable animal reservoir for the Leishmania infection in the endemic region in Bangladesh. However, further studies are required to determine the ability of dogs to transmit the L. donovani to the vector sand fly in nature and its evidence on ‘One Health’ perspectives. Keywords: Visceral leishmaniasis, Endemic region, Stray dogs, rK39 strip test, Giemsa’s stained liver and spleen impression smears, PCR, Reservoir host, Mymensingh


2020 ◽  
Vol 19 (9) ◽  
pp. 676-690 ◽  
Author(s):  
Roma Ghai ◽  
Kandasamy Nagarajan ◽  
Meenakshi Arora ◽  
Parul Grover ◽  
Nazakat Ali ◽  
...  

Alzheimer’s Disease (AD) is a chronic, devastating dysfunction of neurons in the brain leading to dementia. It mainly arises due to neuronal injury in the cerebral cortex and hippocampus area of the brain and is clinically manifested as a progressive mental failure, disordered cognitive functions, personality changes, reduced verbal fluency and impairment of speech. The pathology behind AD is the formation of intraneuronal fibrillary tangles, deposition of amyloid plaque and decline in choline acetyltransferase and loss of cholinergic neurons. Tragically, the disease cannot be cured, but its progression can be halted. Various cholinesterase inhibitors available in the market like Tacrine, Donepezil, Galantamine, Rivastigmine, etc. are being used to manage the symptoms of Alzheimer’s disease. The paper’s objective is to throw light not only on the cellular/genetic basis of the disease, but also on the current trends and various strategies of treatment including the use of phytopharmaceuticals and nutraceuticals. Enormous literature survey was conducted and published articles of PubMed, Scifinder, Google Scholar, Clinical Trials.org and Alzheimer Association reports were studied intensively to consolidate the information on the strategies available to combat Alzheimer’s disease. Currently, several strategies are being investigated for the treatment of Alzheimer’s disease. Immunotherapies targeting amyloid-beta plaques, tau protein and neural pathways are undergoing clinical trials. Moreover, antisense oligonucleotide methodologies are being approached as therapies for its management. Phytopharmaceuticals and nutraceuticals are also gaining attention in overcoming the symptoms related to AD. The present review article concludes that novel and traditional therapies simultaneously promise future hope for AD treatment.


2002 ◽  
Vol 46 (8) ◽  
pp. 2420-2426 ◽  
Author(s):  
Karl V. Clemons ◽  
Raymond A. Sobel ◽  
Paul L. Williams ◽  
Demosthenes Pappagianis ◽  
David A. Stevens

ABSTRACT The efficacy of intravenously administered liposomal amphotericin B (AmBisome [AmBi]) for the treatment of experimental coccidioidal meningitis was compared with those of oral fluconazole (FLC) and intravenously administered conventional amphotericin B (AMB). Male New Zealand White rabbits were infected by intracisternal inoculation of arthroconidia of Coccidioides immitis. Starting 5 days postinfection, animals received one of the following: 5% dextrose water diluent; AMB given at 1 mg/kg of body weight; AmBi given at 7.5, 15, or 22.5 mg/kg intravenously three times per week for 3 weeks; or oral FLC given at 80 mg/kg for 19 days. One week after the cessation of therapy, all survivors were euthanatized, the numbers of CFU remaining in the spinal cord and brain were determined, and histological analyses were performed. All AmBi-, FLC-, or AMB-treated animals survived and had prolonged lengths of survival compared with those for the controls (P < 0.0001). Treated groups had significantly lower numbers of white blood cells and significantly lower protein concentrations in the cerebrospinal fluid compared with those for the controls (P < 0.01 to 0.0005) and had fewer clinical signs of infection (e.g., weight loss, elevated temperature, and neurological abnormalities including motor abnormalities). The mean histological scores for AmBi-treated rabbits were lower than those for FLC-treated and control rabbits (P < 0.016 and 0.0005, respectively); the scores for AMB-treated animals were lower than those for the controls (P < 0.0005) but were similar to those for FLC-treated rabbits. All regimens reduced the numbers of CFU in the brain and spinal cord compared with those for the controls (P ≤0.0005). AmBi-treated animals had 3- to 11-fold lower numbers of CFU than FLC-treated rabbits and 6- to 35-fold lower numbers of CFU than AmB-treated rabbits. Three of eight animals given 15 mg of AmBi per kg had no detectable infection in either tissue, whereas other doses of AmBi or FLC cleared either the brain or the spinal cord of infection in fewer rabbits. In addition, clearance of the infection from both tissues was achieved in none of the rabbits, and neither tissue was cleared of infection in AMB-treated animals. Overall, these data indicate that intravenously administered AmBi is superior to oral FLC or intravenous AMB and that FLC is better than AMB against experimental coccidioidal meningitis. These data indicate that AmBi may offer an improvement in the treatment of coccidioidal meningitis. Additional studies are warranted.


Genes ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 682
Author(s):  
Matthias Christen ◽  
Nils Janzen ◽  
Anne Fraser ◽  
Adrian C. Sewell ◽  
Vidhya Jagannathan ◽  
...  

A 7-month-old, spayed female, domestic longhair cat with L-2-hydroxyglutaric aciduria (L-2-HGA) was investigated. The aim of this study was to investigate the clinical signs, metabolic changes and underlying genetic defect. The owner of the cat reported a 4-month history of multiple paroxysmal seizure-like episodes, characterized by running around the house, often in circles, with abnormal behavior, bumping into obstacles, salivating and often urinating. The episodes were followed by a period of disorientation and inappetence. Neurological examination revealed an absent bilateral menace response. Routine blood work revealed mild microcytic anemia but biochemistry, ammonia, lactate and pre- and post-prandial bile acids were unremarkable. MRI of the brain identified multifocal, bilaterally symmetrical and T2-weighted hyperintensities within the prosencephalon, mesencephalon and metencephalon, primarily affecting the grey matter. Urinary organic acids identified highly increased levels of L-2-hydroxyglutaric acid. The cat was treated with the anticonvulsants levetiracetam and phenobarbitone and has been seizure-free for 16 months. We sequenced the genome of the affected cat and compared the data to 48 control genomes. L2HGDH, coding for L-2-hydroxyglutarate dehydrogenase, was investigated as the top functional candidate gene. This search revealed a single private protein-changing variant in the affected cat. The identified homozygous variant, XM_023255678.1:c.1301A>G, is predicted to result in an amino acid change in the L2HGDH protein, XP_023111446.1:p.His434Arg. The available clinical and biochemical data together with current knowledge about L2HGDH variants and their functional impact in humans and dogs allow us to classify the p.His434Arg variant as a causative variant for the observed neurological signs in this cat.


1979 ◽  
Vol 51 (5) ◽  
pp. 587-596 ◽  
Author(s):  
Albert N. Martins ◽  
Ralph E. Severance ◽  
James M. Henry ◽  
Thomas F. Doyle

✓ The authors have designed an experiment to detect a hitherto unrecognized interaction between high doses of the glucocorticoid, dexamethasone, and brain irradiation. Eighteen juvenile male rhesus monkeys received 1800 rads to the whole brain in 8.5 minutes. For 1½ days before and 10½ days after the irradiation, nine animals received approximately 2.9 mg/kg/day of dexamethasone intramuscularly in addition to irradiation, while the remaining nine animals served as the control group and received saline. All animals eventually developed a progressive neurological syndrome, and died of delayed radiation necrosis of the brain. The two groups were compared with regard to latency to onset of clinical signs, survival time, and number, distribution, and location of lesions of radionecrosis. Large doses of dexamethasone did not alter the susceptibility of the primate brain to delayed radiation necrosis. Detailed morphological study of the radionecrotic lesions supports the hypothesis that most, if not all, of the lesions develop as the consequence of injury to blood vessels.


2019 ◽  
Vol 47 ◽  
Author(s):  
Viviane Motta dos Santos Moretto ◽  
Luciana Maria Curtio Soares ◽  
Esthefanie Nunes ◽  
Uiara Hanna Araújo Barreto ◽  
Valéria Régia Franco Sousa ◽  
...  

Background: Cerebral cavernous hemangioma is a rare neoplasm of vascular origin in the brain, characterized by abnormally dilated vascular channels surrounded by endothelium without muscle or elastic fibers. Presumptive diagnosis is performed by magnetic resonance or computed tomography (CT) scanning and can be confirmed by histopathology. The prognosis of intracranial cavernous hemangioma is poor, with progression of clinical signs culminating in spontaneous death or euthanasia. The purpose of this paper is to report a case of cerebral cavernous hemangioma in a dog, presenting the clinical findings, tomographic changes, and pathological findings.Case: This case involved a 2-year-old medium sized mixed breed female dog presenting with apathy, hyporexia, ataxia, bradycardia, dyspnea, and seizure episodes for three days. Hemogram and serum biochemistry of renal and hepatic function and urinalysis did not reveal any visible changes. CT scanning was also performed. The scans revealed a hyperdense nodule of 15.9 x 14 mm, with well defined borders, and a hypodense halo without post-contrast enhancement and mass effect in the right parietal lobe was observed in both transverse and coronal sections. Based on the image presented in the CT scans, the nodule was defined as a hemorrhagic brain lesion. The animal died after a seizure. The right telencephalon was subjected to necropsy, which revealed a reddish-black wel-defined nodule 1.7 cm in diameter extending from the height of the piriform lobe to the olfactory trine at the groove level and extending towards the lateral ventricle, with slight compression and deformation of the thalamus but no other macroscopic alterations in the other organs. The histopathology indicated that this nodular area in the encephalus contained moderate, well-delimited but unencapsulated cellularity, composed of large vascular spaces paved with endothelial cells filled with erythrocytes, some containing eosinophilic fibrillar material (fibrin) and others with organized thrombus containing occasional neutrophil aggregates. The endothelial cells had cytoplasm with indistinct borders, elongated nuclei, scanty crust-like chromatin, and cellular pleomorphism ranging from discrete to moderate, without mitotic figures.Discussion: The histological findings characterized the morphological changes in the brain as cavernous hemangioma, and the growth and compression of this neoplasm were considered the cause of the clinical signs of this dog. The main complaint was seizures, although ataxia and lethargy were also noted. These clinical signs are often related to changes in the anterior brain and brainstem. The literature does not list computed tomography as a complementary diagnostic method in cases of cerebral cavernous hemangioma in dogs, but CT scanning was useful in confirming cerebral hemorrhage. The main differential diagnosis for cerebral cavernous hemangioma would be a hamartoma, but what differentiates them histologically is the presence of normal interstices between the blood vessels, since no intervening neural tissue occurs in the case of cerebral hemangioma. Therefore, even in the absence of immunohistochemistry to more confidently confirm a cavernous hemangioma, the clinical signs, CT scans and especially the pathological findings were consistent with a case of cerebral cavernous hemangioma, a benign neoplasm with a poor prognosis due to the severe neurological changes it causes and its difficult treatment.


2021 ◽  
Vol 31 (Supplement_2) ◽  
Author(s):  
Maiara Carolina Perussolo ◽  
Bassam Felipe Mogharbel ◽  
Lucia de Noronha ◽  
Katherine Athayde Teixeira de Carvalho

Abstract Background Multiple sclerosis (MS) is an autoimmune disease of the central nervous system, characterized as an inflammatory demyelinating disease. It presents a diversity of neurologic signs and symptoms as well the incapacities. Since the need for advances in MS treatment, many studies are for new therapeutic technologies, mainly through using preclinical models as experimental autoimmune encephalomyelitis (EAE). This study aimed to observe and analyze the development in Lewis rats-induced model of EAE. Methods It was used 23 females of Rattus norvegicus, from 6 to 8 weeks, weighing around 170 g. Of 23 rats, 19 underwent EAE induction distributed in six groups to establish the evolution of clinical signs. B. pertussis toxin (PTX) doses were 200, 250, 300, 350–400 ng, and four animals as the control group. The animals had weight and scores analyzed daily, starting seven and ending 24 days after induction. Then, all animals were euthanized, and the brain and spinal cord were collected for histopathological analyses. Results The results showed that the dose of 250 ng of PTX induced de higher score and weight reduction. All groups who received the PTX demonstrated histopathological findings. Those characterized as leukocyte infiltration, activation of microglia and astrocytes, and demyelinated plaques in the brain. In the spinal cord, the loosening of the myelinated fibers was observed by increasing the axonal space in all tested doses of PTX. Conclusions EAE was not dose-dependent. Histopathological findings do not proportionally related to clinical signs, as in human patients with MS.


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