DrugMechDB: A Curated Database of Drug Mechanisms

Computational drug repositioning methods have emerged as an attractive and effective solution to find new candidates for existing therapies, reducing the time and cost of drug development. Repositioning methods based on biomedical knowledge graphs typically offer useful supporting biological evidence. This evidence is based on reasoning chains or subgraphs that connect a drug to a disease prediction. However, there are no databases of drug mechanisms that can be used to train and evaluate such methods. Here, we introduce the Drug Mechanism Database (DrugMechDB), a manually curated database that describes drug mechanisms as paths through a knowledge graph. DrugMechDB integrates a diverse range of authoritative free-text resources to describe 4,583 drug indications with 32,249 relationships, representing 14 major biological scales. DrugMechDB can be employed as a benchmark dataset for assessing computational drug repositioning models or as a valuable resource for training such models.

DrugMechDB: A Curated Database of Drug Mechanisms

Computational drug repositioning methods have emerged as an attractive and effective solution to find new candidates for existing therapies, reducing the time and cost of drug development. Repositioning methods based on biomedical knowledge graphs typically offer useful supporting biological evidence. This evidence is based on reasoning chains or subgraphs that connect a drug to disease predictions. However, there are no databases of drug mechanisms that can be used to train and evaluate such methods. Here, we introduce the Drug Mechanism Database (DrugMechDB), a manually curated database that describes drug mechanisms as paths through a knowledge graph. DrugMechDB integrates a diverse range of authoritative free-text resources to describe 4,583 drug indications with 32,249 relationships, representing 14 major biological scales. DrugMechDB can be employed as a benchmark dataset for assessing computational drug repurposing models or as a valuable resource for training such models.

25 Cerebellar cognitive affective syndrome – a case report of diagnosis and management using selective serotonin and norepinephrine reuptake inhibitors

Objectives/aims

The objective of this case is to describe and report on a case of Cerebellar Cognitive Affective Syndrome (CCAS) which improved after the use of high dose venlafaxine therapy. To our knowledge, there are only a few case reports discussing on the effectiveness of various drug therapies in CCAS patients and none had reported on the use of Selective Serotonin and Norepinephrine Reuptake Inhibitors (SNRI).

Methods

We describe a 55-year-old male with a history of partially excised grade 1 left cerebellar haemangioblastoma in 2005 followed by Gamma Knife in 2006.

Unfortunately, he suffered a recurrence in 2018 requiring embolisation of the haemangioblastoma followed with surgery to resect the tumour. He presented to our specialist neuropsychiatric unit following episodes of new acute unprovoked behavioural changes after surgery. During these episodes, he would become verbally abusive, refuse to engage in any rehab activity, refuse any oral intake, become sexually disinhibited, and experience distressing hallucinations. On the neuropsychiatric ward, he continued to have episodes of severe emotional regulation difficulties. There were no obvious triggers identified and it was noted that the peaks and troughs in his behaviour lasted for a few days before self-resolving and did not follow any particular pattern. In between these episodes, the patient was pleasant, engaging in physiotherapy, and conversed normally with staff.

Results

He scored a total of 4 out of 10 on the CCAS-scale. A diagnosis of CCAS was concluded given the extensive history of cerebellar injury, nature of presenting complain, and his CCAS-scale score. He was started on high dose SNRI (Venlafaxine XL 150 mg BD). On repeating the CCAS-scale after being on SNRI for 4 months, his score was worse at 6 out of 10. However, we observed a decrease in the frequency, duration, and severity of behavioural change after commencement of SNRI. He benefited greatly from physiotherapy on the ward however despite our best efforts functional independence was not regained. He had to be transferred with the aid of 2 members of staff and mobilises with the aid of an electronic wheelchair.

Conclusions

CCAS is a complex disease and the management is yet to be agreed on by the neuropsychiatry community. Our case report illustrated the therapeutic benefit of venlafaxine in the treatment of severe emotional regulation difficulties associated with resection of a cerebellar haemangioblastoma. Furthermore, patients with cerebellar injuries should be managed in a multi-disciplinary manner with input from neurology, neuropsychiatry, neuropsychology, occupational therapist, and physiotherapist.

Glioma Indian scenario: Is there a human leucocyte antigen association?

Background:

The central nervous system tumors are a rare neoplasm with little knowledge with Human Leukocyte Antigen (HLA) involvement. Primary brain tumors are cancers that originate in brain classified according to their appearance under a microscope as low grade (grade I and II) with diffuse astrocytomas, pliocytic astrocytomas, oligodendrogliomas, gangliogliomas, and mixed gliomas as common subtypes and high grade (grade III and IV).

Materials and Methods:

HLA associations in common glioma are reported from other parts of the world. The normal cancer treatment is surgery, followed by radiotherapy, and chemotherapy; nowadays immunotherapy is advised. HLA distribution in a Glioma patient was done based on serology and molecular techniques. The immune response gene studies have implicated the HLA allele association in most of the common diseases from India. Considerable variations are noted in HLA association with cancers; hence, we have summarized the HLA involvement in Glioma with respect to the literature.

Results:

HLA A*030101, A*310102, B*350101, B*4406, Cw*040101, Cw*070101, DRB1*070101, and DRB1*1001.

Conclusion:

Ethnic diversity and HLA polymorphism precipitate differential immune response genes involved in variable disease manifestations. Therefore, caste-specific HLA allelic specificity needs to be identified, which may help in early identification of the associated HLA allele and establishing clinical practices among glioma patients.

HLA diversity among Nadars, a primitive Dravidian caste of South India

South India is one of the oldest geophysical regions mainly occupied by Dravidian language-speaking people. Here a random panel of 61 unrelated Nadar healthy individual from Tamil Nadu State were analyzed and compared with other populations of India and the world. HLA-A, B and C alleles frequencies and their haplotype frequencies were determined by high-resolution typing of genomic DNA. The analysis revealed that the Nadar caste of South India have several characters shared with East Asian populations consistent with the demographic history of South India, as well as specific features including several unique alleles such as A*03011, A*31011, B*15011, B*3501, B*51011, Cw*02022. In addition, haplotypes such as A*31011-Cw*02022-B*3501, A*03011-Cw*04011-B*4406 and A*2402101-Cw*04011-B*51011 are of high frequency in both these populations but are rare or absent in other populations of India and the world. The study suggests that a comparatively lesser degree of genetic admixture occurred between the South Indian and North Indian racial groups than that between South Indian and East Asian groups.