Synthesis and biological evaluation of Ribo 7-N/O/S pyrimidine 9-deaza C-nucleoside analogs as new antiviral agents for inhibiting HCV RNA-dependent RNA polymerases.

Hepatitis C infection is caused by the bloodborne pathogen hepatitis C virus (HCV) and can lead to serious liver diseases and, ultimately, death if the treatment is ineffective. This work reports the synthesis and preclinical evaluation of 7 novel 9-O/N/S pyrimidine nucleosides, including compound 12, the triphosphate of known compound 7b. The nucleosides are 9-deaza modifications of adenosine and guanosine with ß-2'-C-methyl substituent on the ribose. Within this series of compounds, a 9-deaza furopyrimidine analog of adenosine, compound 7b, showed high anti-HCV activity in vitro, good stability, low toxicity, and low genotoxicity when administrated in low doses, and an adequate pharmacokinetics profile. An improved synthesis of compound 7b compared to a previous study is also reported. Compound 12 was synthesized as a control to verify phosphorylation of 7b occurred in vivo.

Scaffold hopping via ring opening enables identification of acyclic compounds as new complement Factor D inhibitors.

The three complement pathways comprising the early phase of the complement system (the classical, lectin, and alternative pathways) act together with the innate and adaptive immune systems to protect against foreign entities and maintain tissue homeostasis. While these systems are normally under tight regulatory control, several diseases have been reported to correlate with uncontrolled activation and amplification of the alternative pathway, including paroxysmal nocturnal hemoglobinuria, atypical hemolytic uremic syndrome, C3 glomerulopathy, and age-related macular degeneration. Complement FactorD (CFD), a serine protease, is the rate-limiting enzyme for the activity of alternative pathway. CFD activates the alternative pathway by cleaving Complement Factor B complexed to C3b (C3bB) to generate alternative pathway C3 convertase (C3bBb). In our search for novel CFD inhibitors with therapeutic potential, we employed a hot-spot analysis of an ensemble of apo and holo CFD structures. This analysis identified potential pharmacophore features that aided in the design of a series of compounds based on an l-proline core. While these compounds inhibited CFD in an esterolytic assay (for example, a proline-based compound, IC50 = 161 nM), the pharmacokinetic (PK) properties were poor. A strategy of scaffold hopping via ring opening led to a novel series of acyclic compounds, with subsequent structure-based ligand design and lead optimization producing several novel CFD inhibitors. One of these inhibitors, 1-(2-((2-(3-chloro-2-fluorobenzylamino)-2-oxoethyl)(cyclopropyl)amino)-2-oxoethyl)-5-(3-methyl-3-(1-methylpiperidin-4-yl)ureido)-1H-indazole-3-carboxamide, showed good potency with IC50s of 37 nM in the esterolytic assay and 30 nM in a hemolytic assay and PK assessments following oral administration to rats revealed a Cmax of 113 ng/mL and an AUC0-24h of 257 hr.ng/mL.

Discovery and optimization of orally bioavailable and potent plasma Kallikrein inhibitors bearing a quaternary carbon.

Hereditary angioedema (HAE) is a rare and potentially life-threatening disease that affects an estimated 1 in 50,000 individuals worldwide. Berotralstat (BCX7353) is the only small molecule approved by the US Food and Drug Administration (FDA) for the prophylactic treatment of HAE attacks in patients 12 years and older. During the discovery of BCX7353, we also identified a novel series of small molecules containing a quaternary carbon as potent and orally bioavailable Plasma Kallikrein (PKal) inhibitors. Lead compound was identified as a potent inhibitor following a detailed lead optimization process that balanced the lipophilic efficiency (LipE) and pharmacokinetic (PK) profile.

An update on the progress of galidesivir (BCX4430), a broad-spectrum antiviral.

Galidesivir (BCX4430) is an adenosine nucleoside analog that is broadly active in cell culture against several RNA viruses of various families. This activity has also been shown in animal models of viral disease associated with Ebola, Marburg, yellow fever, Zika, and Rift Valley fever viruses. In many cases, the compound is more efficacious in animal models than cell culture activity would predict. Based on favorable data from in vivo animal studies, galidesivir has recently undergone evaluation in several phase I clinical trials, including against severe acute respiratory syndrome coronavirus 2, and as a medical countermeasure for the treatment of Marburg virus disease.

Intracellular rebinding of transition-state analogues provides extended in vivo inhibition lifetimes on human purine nucleoside phosphorylase.

Purine nucleoside phosphorylase (PNP) is part of the human purine salvage pathway. Its deficiency triggers apoptosis of activated T-cells, making it a target for T-cell proliferative disorders. Transition-state analogues of PNP bind with picomolar (pm) dissociation constants. Tight-binding PNP inhibitors show exceptionally long lifetimes on the target enzyme. We solve the mechanism of the target residence time by comparing functional off-rates in vitro and in vivo We report in vitro PNP-inhibitor dissociation rates (t½) from 3 to 31 min for seven Immucillins with dissociation constants of 115 to 6 pm Treatment of human erythrocytes with DADMe-Immucillin-H (DADMe-ImmH, 22 pm) causes complete inhibition of PNP. Loss of [14C]DADMe-ImmH from erythrocytes during multiple washes is slow and biphasic, resulting from inhibitor release and rebinding to PNP catalytic sites. The slow phase gave a t½ of 84 h. Loss of [14C]DADMe-ImmH from erythrocytes in the presence of excess unlabeled DADMe-ImmH increased to a t½ of 1.6 h by preventing rebinding. Thus, in human erythrocytes, rebinding of DADMe-ImmH is 50-fold more likely than diffusional loss of the inhibitor from the erythrocyte. Humans treated with a single oral dose of DADMe-ImmH in phase 1 clinical trials exhibit regain of PNP activity with a t½ of 59 days, corresponding to the erythropoiesis rate in humans. Thus, the PNP catalytic site recapture of DADMe-ImmH is highly favored in vivo We conclude that transition-state analogues with picomolar dissociation constants exhibit long lifetimes on their targets in vivo because the probability of the target enzyme recapturing inhibitor molecules is greater than diffusional loss to the extracellular space.

Efficacy of the broad-spectrum antiviral compound BCX4430 against Zika virus in cell culture and in a mouse model.

Zika virus (ZIKV) is currently undergoing pandemic emergence. While disease is typically subclinical, severe neurologic manifestations in fetuses and newborns after congenital infection underscore an urgent need for antiviral interventions. The adenosine analog BCX4430 has broad-spectrum activity against a wide range of RNA viruses, including potent in vivo activity against yellow fever, Marburg and Ebola viruses. We tested this compound against African and Asian lineage ZIKV in cytopathic effect inhibition and virus yield reduction assays in various cell lines. To further evaluate the efficacy in a relevant animal model, we developed a mouse model of severe ZIKV infection, which recapitulates various human disease manifestations including peripheral virus replication, conjunctivitis, encephalitis and myelitis. Time-course quantification of viral RNA accumulation demonstrated robust viral replication in several relevant tissues, including high and persistent viral loads observed in the brain and testis. The presence of viral RNA in various tissues was confirmed by an infectious culture assay as well as immunohistochemical staining of tissue sections. Treatment of ZIKV-infected mice with BCX4430 significantly improved outcome even when treatment was initiated during the peak of viremia. The demonstration of potent activity of BCX4430 against ZIKV in a lethal mouse model warrant its continued clinical development.

Double non coronary aortic sinuses: an autopsy case finding showing the arterial variation / Senos aórticos dobles, no coronarios: un caso de autopsia que demuestra la variación arterial

We report a case of variant origin of the right coronary artery from the left posterior aortic sinus. This was observed routinely during a medico legal autopsy of a 58 year old male who died in a road traffic accident. Initially it was believed that the right coronary artery was absent since there was no obvious right coronary artery ostium from the anterior aortic sinus. However it was found later that the right coronary ostium was present just beside the left coronary ostium in the left posterior aortic sinus and the right coronary artery was arising from the left posterior aortic sinus. The right coronary artery had an intramural course between the aorta and pulmonary trunk, which is considered as very dangerous and life threatening. We believe that the present case report will be enlightening to the cardiologist and cardiothoracic surgeon. It is also true that the conduction of medico legal autopsies of coronary arteries is important for the medico legal resolution.

Se presenta un caso de variación de origen de la arteria coronaria derecha desde el seno aórtico posterior izquierdo. Esto se observó de forma rutinaria durante una autopsia médico-legal de un hombre de 58 años que murió en un accidente de tránsito. Inicialmente se creía que la arteria coronaria derecha estaba ausente ya que no había un ostium observable desde el seno aórtico anterior. Sin embargo, se descubrió más tarde que el ostium de la arteria coronaria derecha estaba presente justo al lado del ostium de la arteria coronaria izquierda en el seno aórtico posterior izquierdo y la arteria coronaria derecha se originaba del seno aórtico posterior izquierdo. La arteria coronaria derecha presentó un recorrido intramural entre la aorta y el tronco pulmonar, que se considera como muy peligroso y potencialmente mortal. Creemos que el presente trabajo será esclarecedor para el cardiólogo y el cirujano cardiotorácico. También consideramos que el conocimiento de la anatomía de las arterias coronarias es importante durante el desarrollo de la autopsia médico-legal para lograr alcanzar una correcta resolución del proceso medicolegal.

Safety, pharmacokinetics, and pharmacodynamics of avoralstat, an oral plasma kallikrein inhibitor: phase 1 study.

BACKGROUND: Avoralstat is a potent small-molecule oral plasma kallikrein inhibitor under development for treatment of hereditary angioedema (HAE). This first-in-human study evaluated the safety, tolerability, pharmacokinetics, and pharmacodynamics of avoralstat. METHODS: This double-blind, placebo-controlled, ascending-dose cohort trial evaluated avoralstat single doses of 50, 125, 250, 500, and 1000 mg and multiple doses up to 2400 mg daily (100, 200, 400, and 800 mg every 8 h [q8 h] up to 7 days). RESULTS: Avoralstat (n = 71) was generally well tolerated with no signals for a safety concern; there were no serious adverse events (AEs) or discontinuations due to AEs, and compared to placebo (n = 18), no notable difference in AEs. Four moderate severity AEs were reported in two subjects; syncope after a single 250 mg dose (one subject) and abdominal pain, back pain, and eczema after multiple doses of 800 mg avoralstat (one subject). For multiple-dose cohorts, the incidence of gastrointestinal AEs was highest at the 2400 mg/day dose. Elimination of avoralstat was bi-exponential with a terminal half-life of 12-31 h. Inhibition of plasma kallikrein was observed at all doses, and the degree of inhibition was highly correlated with avoralstat concentrations (R = 0.93). Mean avoralstat concentrations at doses ≥400 mg q8 h met or exceeded plasma kallikrein EC50 values throughout the dosing interval. CONCLUSION: Avoralstat was well tolerated, and drug exposure was sufficient to meet target levels for inhibition of plasma kallikrein. Based on these results, the 400 mg q8 h dose was selected for further evaluation in patients with HAE.

An unusual site for a snakebite.

Snakebites are an important cause of death in rural and suburban India. Most of these deaths occur due to envenomation. The incidence of snake bite is highest in developing countries with the most common site of such bites in the lower limbs. Here, we present a case where a 12-year-old boy had been bitten on his face which is an unusual site and as a consequence the treating doctor failed to make the correct diagnosis promptly and the boy died.

Ligature mark on the face - forensic implications.

In deaths due to hanging and strangulation, the position, course and direction of the ligature mark, the kind of knot used and injuries to the neck structures help in deducing the cause and manner of death. Two cases of suicidal hanging are reported where the unusual positioning of ligature and presence of the ligature mark on the face raise doubts concerning the circumstances of death. The presence of a ligature mark on the face is an unusual and rarely reported phenomenon that can have serious medico-legal implications.

Sudden unexpected death due to strangulated inguinal hernia.

Sudden unwitnessed, unexpected deaths when the bodies are found in public places require a complete and meticulous medicolegal autopsy to ascertain the cause and manner of death to avoid further unnecessary investigations by the legal authorities. Such deaths attributed to gastrointestinal causes at autopsy are relatively uncommon. We report a case of sudden unexpected death due to strangulated inguinal hernia in a 60-year-old man. The body was discovered in a public area near a place of worship. The present case illustrates a potentially preventable sudden unexpected death due to a surgically correctable gastrointestinal condition. In the present case, the individual feared being hospitalised for treatment of his scrotal swelling with potential surgery and the eventual loss of daily income. In our opinion, such apprehensions may have delayed the potentially life-saving hospital surgical intervention in the individual.

Proportion of depression and its determinants among type 2 diabetes mellitus patients in various tertiary care hospitals in Mangalore city of South India.

BACKGROUND: Depression is found to be common among patients with diabetes and it is associated with poor outcomes in disease control. This study was carried out to find out the proportion and determinants associated with depression among patients with established type 2 diabetes mellitus (T2DM) in various tertiary care hospitals in Mangalore city of south India. MATERIALS AND METHODS: This study was conducted in one government and three private tertiary care hospitals in Mangalore in December 2010. All consenting patients with confirmed diagnosis of T2DM were interviewed and screened for depression by administering the 9-item PRIME-MD Patient Health Questionnaire (PHQ-9). RESULTS: Of the 230 T2DM patients, 119 (51.7%) were males. The mean age of all participants was 53.61 ± 10.7 years. The median duration of T2DM was found to be 12.1 ± 7.35 years. Among the participants, 71 (30.9%) met the criteria for moderate depression, 33 (14.3%) for severe depression, and the remaining 126 (54.8%) had no clinically significant depression. Only 26 (11.3%) patients were already aware that they were depressed, of whom just 3 had taken medical consultation. Among the risk factors, depression was found to be significantly associated with older age, female gender, low socioeconomic status, unskilled and retired employment status, having complications due to T2DM or comorbidities like hypertension and coronary artery disease, being overweight and being on insulin syringe injections. CONCLUSION: This study found a high proportion of depression among patients with T2DM. Therefore the care of individuals with diabetes mellitus (DM) should include the screening and possible treatment of depression in order to achieve and sustain treatment goals.

Rituals can kill - A fatal case of brucine poisoning.

In some parts of India people follow a religious ritual of drinking an herbal preparation made from the bark of the Alstonia scholaris tree (Blackboard tree) on the day of the new moon in the month of July. This tree could be easily confused with the Strychnos nux vomica tree. Brucine is the predominant alkaloid present in the bark of the Strychnos nux vomica tree. The toxicological property of brucine is similar to strychnine. Brucine is a neurotoxin. A 29-year-old male presented with a history of consumption of an herbal preparation made from the bark of the Strychnos nux vomica tree confusing it for Alstonia scholaris. Soon after, he developed convulsions and later died in hospital on the same day. The aim of this case report is to highlight the fact that people must be cautious when they follow religious rituals.

Colchicine poisoning: a case report and review of literature.

Colchicine, a natural pseudo-alkaloid found in plants such as the Colchicum autumnale and Gloriosa superba has tremendous medicinal properties, but if misused by an unqualified person can result in fatal consequences. We report a case of colchicine poisoning in an adult man as a result of consumption of the herb G. superba by a 50-year-old man and review the literature.

Mortality among homeless and unclaimed bodies in Mangalore city - An insight.

Homelessness is a social as well as legal stigma on a Country's development index. In addition homeless people are exposed to increased incidence of diseases and accidents. Mangalore city, a bustling city located in Southern costal region of India, has seen tremendous growth in the past few years; with this the problem of migrants and homeless has also increased. This has invited a spectrum of problems relating to law and order including frequent incidences of unclaimed dead bodies, both due to natural and unnatural causes. This autopsy based study tries to highlight the situation of picture of homeless deaths in Mangalore and the problems faced by the Law enforcing authorities.

Adenomyomatous polyp of the uterus: Report of an autopsy case and review of the literature.

Adenomyomatous polyps of the endometrium are a rare subtype of endometrial polyps. In addition to the usual features of endometrial polyps, they also contain a smooth muscle component. Grossly they appear no different than ordinary endometrial polyps. In the case reported herein, a 23-year-old nulliparous female was killed in a traffic accident. In the course of the medicolegal autopsy, a small pedunculated growth was identified in the fundus of the endometrial cavity. Histologically the mass consisted of endometrial glands intimately mixed with smooth muscle and thick walled blood vessels, consistent with an adenomyomatous polyp. There was no history of tamoxifen use in this individual. To our knowledge this is the first report of post-mortem diagnosis of an adenomyomatous polyp. Furthermore, this is the first report of an individual with this diagnosis younger than the fourth decade. In the medicolegal setting, forensic pathologists are constantly faced with entities that, while they may not have caused death, may serve to educate practitioners about rare lesions. This individual's finding serves as one of those entities. This case reiterates the importance of the autopsy as not only the answer to an individual's death, but as an avenue for the discovery of entities that may have relevance to those who are still living.

Combinations of favipiravir and peramivir for the treatment of pandemic influenza A/California/04/2009 (H1N1) virus infections in mice.

Favipiravir, an influenza virus RNA polymerase inhibitor, and peramivir, an influenza virus neuraminidase inhibitor, were evaluated alone and in combination against pandemic influenza A/California/04/2009 (H1N1) virus infections in mice. Infected mice were treated twice daily for 5 d starting 4 h after virus challenge. Favipiravir was 40%, 70%, and 100% protective at 20, 40, and 100 mg/kg/d. Peramivir was 30% protective at 0.5 mg/kg/d, but ineffective at lower doses when used as monotherapy. Combinations of favipiravir and peramivir increased the numbers of survivors by 10-50% when the 0.025, 0.05, and 0.1 mg/kg/d doses of peramivir were combined with 20 mg/kg/d favipiravir and when all doses of peramivir were combined with 40 mg/kg/d favipiravir. Three-dimensional analysis of drug interactions using the MacSynergy method indicates strong synergy for these drug combinations. In addition, an increase in lifespan for groups of mice treated with drug combinations, compared to the most effective monotherapy group, was observed for the 0.025, 0.05, and 0.1 mg/kg/d doses of peramivir combined with favipiravir at the 20 mg dose level. Therefore, the 20 mg/kg/d dose of favipiravir was selected for further combination studies. Increased survival was exhibited when this dose was combined with peramivir doses of 0.1, 0.25 and 0.5 mg/kg/d (1 mg/kg/d of peramivir alone was 100% protective in this experiment). Improved body weight relative to either compound alone was evident using 0.25, 0.5, and 1 mg/kg/d of peramivir. Significant reductions in lung hemorrhage score and lung weight were evident on day 6 post-infection. In addition, virus titers were reduced significantly on day 4 post-infection by combination therapy containing favipiravir combined with peramivir at 0.25 and 0.5 mg/kg/d. These data demonstrate that combinations of favipiravir and peramivir perform better than suboptimal doses of each compound alone for the treatment of influenza virus infections in mice.

Sex estimation from foramen magnum dimensions in an Indian population.

Identification of skeletal remains is vital in forensic investigations. The need for methods to estimate sex from cranial fragments becomes apparent when only a part of skull is brought for identification. The present research is an attempt to study the sexual dimorphism of the anteroposterior diameter, transverse diameter and area of foramen magnum in a population of costal Karnataka region using statistical considerations. Ninety adult dry skulls of known sex (50 male and 40 female) were included in the study. Morphometric analysis of foramen magnum was conducted using vernier calipers and the area of foramen magnum was calculated. The anteroposterior diameter, transverse diameter and area of foramen magnum are found to be significantly larger in males than females. Binary Logistic Regression (BLR) analysis was performed to derive models for estimation of sex from the different measurements of foramen magnum and Receiver Operating Characteristic (ROC) curve was drawn for the predicted probabilities obtained from BLR analysis. The predictability of foramen magnum measurements in sexing of crania was 65.4% for transverse diameter and 86.5% for the anteroposterior diameter. For the area of foramen magnum that was calculated using the formula derived by Radinsky and Teixeria, the predicted probabilities were observed to be 81.6% and 82.2% respectively. When anteroposterior and transverse diameter were used together in BLR analysis the predictability of sex increased to 88%. However, considering the overlapping in the male and female values for the foramen magnum measurements it is suggested that its application in sex estimation should be restricted to cases where only a fragment of base of the skull is brought for examination. In such cases, the anteroposterior diameter and area of the foramen magnum can be employed as better tools for sexing the skulls than the transverse diameter of the foramen magnum.

The Mangalore aircrash of 22 May 2010: practical problems related to identification of the dead in a populous developing country.

It was a sad and emotional moment for the citizens of Mangalore, India when the "Dubai to Mangalore" Air India Express Boeing 737-800 flight IX-812 crashed at the Mangalore International Airport on 22 May 2010, killing 158 people on board. Identification of the victims was difficult as most of the bodies were charred beyond easy recognition. The practical problems faced by the legal authorities in identifying the charred victims in a populous and developing country like India are discussed in this paper.