Mesenchymal Stem Cell Therapy in the Treatment of Neurodegenerative Cerebellar Ataxias: a Systematic Review and Meta-analysis.

The objective of this study is to synthesise the findings of clinical studies in order to derive evidence for use of the mesenchymal stem cell (MSC) therapy in the treatment of neurodegenerative cerebellar ataxias. In order to find relevant studies for the systematic review, we searched through Medline (1985 to July 2020), PubMed and Clinical trial register. We included both single-arm and comparative studies in which MSCs were given as intervention in neurodegenerative ataxia patients at any time after the diagnosis. We used Joanna Briggs Institute (JBI) quality scale to evaluate the methodological qualities of the included studies. Our literature search obtained 81 publications. Three articles comprising a total of 47 patients were included in the meta-analysis. None of them were randomised controlled trials (RCTs). Pooled analysis noted that there was a decrease in the Berg Balance Scale (BBS)/Scale for the Assessment and Rating of Ataxia (SARA) score from pre to post assessment; however, the difference was statistically not significant (standardised mean difference (SMD) - 0.20; 95% CI - 0.78 to 0.38). No significant side effects were reported in any of the studies. We did not observe any statistically significant difference in the pooled mean difference in the International Cooperative Ataxia Rating Scale (ICARS) score between pre and post assessment in patients with ataxia after receiving the stem cells (SMD 0.36, 95% CI - 0.08 to 0.81). Our systematic review and meta-analysis concluded that MSC cell therapy appeared safe but provided insufficient evidence to support the use of MSCs to treat patients with neurodegenerative cerebellar ataxia at present. No l RCTs was available in the literature to test efficacy; therefore, well-designed RCTs are needed to ascertain the effectiveness of MSCs in patients with neurodegenerative cerebellar ataxias.

Impact of the COVID-19 Pandemic on the Frequency, Clinical Spectrum and Outcomes of Pediatric Guillain-Barré Syndrome in India: A Multicentric Ambispective Cohort Study.

Objective: To study impact of COVID-19 pandemic on frequency, clinical/electrophysiological profile and treatment outcomes in pediatric Guillain-Barré syndrome (GBS). Background: GBS is the most frequent cause of pediatric acute flaccid paralysis. The effect of the COVID-19 pandemic on pediatric GBS is unclear in the literature. Methods: We conducted an ambispective, multicentric, cohort study involving 12 of 27 centres in GBS Consortium, during two periods: pre-COVID-19 (March-August 2019) and during COVID-19 (March-August 2020). Children ≤12 years who satisfied National Institute of Neurological Diseases and Stroke criteria for GBS/variants were enrolled. Details pertaining to clinical/laboratory parameters, treatment and outcomes (modified Rankin Scale (mRS) at discharge, GBS Disability score at discharge and 3 months) were analysed. Results: We enrolled 33 children in 2019 and 10 in 2020. Children in 2020 were older (median 10.4 [interquartile range 6.75-11.25] years versus 5 (2.5-8.4) years; P = 0.022) and had more sensory symptoms (50% versus 18.2%; P = 0.043). The 2020 group had relatively favourable mRS at discharge (median 1 (1-3.5) versus 3 (2-4); P = 0.042) and GBS disability score at 3 months (median 0 (0-0.75) versus 2 (0-3); P = 0.009) compared to 2019. Multivariate analysis revealed bowel involvement (P = 0.000) and ventilatory support (P = 0.001) as independent predictors of disability. No child in 2020 had preceding/concurrent SARS-CoV2 infection. Conclusions: The COVID-19 pandemic led to a marked decline in pediatric GBS presenting to hospitals. Antecedent illnesses, clinical and electrophysiological profile of GBS remained largely unchanged from the pre-pandemic era.

Impact of COVID-19 on Guillain-Barre Syndrome in India: A Multicenter Ambispective Cohort Study.

Introduction/Aims: Studies conducted during the coronavirus disease 2019 (COVID-19) pandemic have reported varied data regarding the incidence of Guillain-Barre syndrome (GBS). The present study investigated demographic and clinical features, management, and outcomes of patients with GBS during a specified period of the COVID-19 pandemic, and compared these features to those of GBS in the previous year. Methods: A multicenter, ambispective cohort study including 26 centers across India was conducted. Data from a pre-COVID-19 period (March 1 to August 31, 2019) were collected retrospectively and collected ambispectively for a specified COVID-19 period (March 1 to August 31, 2020). The study was registered with the Clinical Trial Registry India (CTRI/2020/11/029143). Results: Data from 555 patients were included for analysis: pre-COVID-19 (n = 334) and COVID-19 (n = 221). Males were more commonly affected during both periods (male:female, 2:1). Gastroenteritis was the most frequent antecedent event in 2019 (17.4%), whereas fever was the most common event in 2020 (10.7%). Paraparesis (21.3% versus [vs.] 9.3%, P = 0.001) and sensory involvement (51.1% vs. 41.3%; P = 0.023) were more common during COVID-19 in 2020, whereas back pain (26.3% vs. 18.4%; P = 0.032) and bowel symptoms (20.7% vs. 13.7%; P = 0.024) were more frequent in the pre-COVID period. There was no difference in clinical outcomes between the two groups in terms of GBS disability score at discharge and 3 months after discharge. Independent predictors of disability in the pre-COVID period included areflexia/hyporeflexia, the requirementfor intubation, and time to bulbar weakness; in the COVID-19 period, independent predictors included time from onset to admission, intubation, and intubation requirement. The mortality rate was 2.3% during the entire study period (13/555 cases). Discussion: Results of this study revealed an overall reduction in the frequency of GBS during the pandemic. The lockdown likely reduced the risk for antecedent infections due to social distancing and improved hygiene, which may have resulted in the reduction of the frequency of GBS.

Amitraz Poisoning: The not so (Un)common Poisoning.

Amitraz is a widely used insecticide and antiparasitic drug. It can cause poisoning in humans via oral, inhalation, and dermal routes. Clinical features hence produced may mimic organophosphate (OP) poisoning because of several shared features (miosis, bradycardia, hypotension) along with a history of possible insecticide poisoning. But the presence of hyperglycemia, hypothermia, and reduced gastrointestinal motility along with normal serum cholinesterase levels and the absence of fasciculations and a hypersecretory state (salivation, lacrimation, perspiration, and diarrhea) point against OP poisoning. Analysis of the poison container also helps confirm the poison. Management is mostly supportive with a good prognosis.

Pulmonary Hypertension and Pulmonary Aspergilloma-Coexistence of Two Rare Sequelae of Pulmonary Embolism.

We report a 42 year old non-smoker male who presented with progressive exertional dyspnoea, productive cough with streaky hemoptysis and progressive pedal edema. His physical examination, ECG, chest X-ray and 2D-ECHO revealed features suggestive of right heart failure and pulmonary hypertension. On further evaluation for the cause of pulmonary hypertension, his CT pulmonary angiography revealed features of chronic pulmonary thromboembolism with calcified thrombus in the main pulmonary artery along with pulmonary hypertension. Incidentally the CT also revealed a cavity in the right lung with soft tissue within it. A, trans-thoracic needle aspiration of this tissue was suggestive of an aspergilloma. This is a rare case report of co-existence of two uncommon complications of pulmonary embolism-chronic thrombo-embolic pulmonary hypertension and pulmonary Aspergilloma in the same patient.

The Rho kinase inhibitor azaindole-1 has long-acting vasodilator activity in the pulmonary vascular bed of the intact chest rat.

Responses to a selective azaindole-based Rho kinase (ROCK) inhibitor (azaindole-1) were investigated in the rat. Intravenous injections of azaindole-1 (10-300 µg/kg), produced small decreases in pulmonary arterial pressure and larger decreases in systemic arterial pressure without changing cardiac output. Responses to azaindole-1 were slow in onset and long in duration. When baseline pulmonary vascular tone was increased with U46619 or L-NAME, the decreases in pulmonary arterial pressure in response to the ROCK inhibitor were increased. The ROCK inhibitor attenuated the increase in pulmonary arterial pressure in response to ventilatory hypoxia. Azaindole-1 decreased pulmonary and systemic arterial pressures in rats with monocrotaline-induced pulmonary hypertension. These results show that azaindole-1 has significant vasodilator activity in the pulmonary and systemic vascular beds and that responses are larger, slower in onset, and longer in duration when compared with the prototypical agent fasudil. Azaindole-1 reversed hypoxic pulmonary vasoconstriction and decreased pulmonary and systemic arterial pressures in a similar manner in rats with monocrotaline-induced pulmonary hypertension. These data suggest that ROCK is involved in regulating baseline tone in the pulmonary and systemic vascular beds, and that ROCK inhibition will promote vasodilation when tone is increased by diverse stimuli including treatment with monocrotaline.

Peroxynitrite has potent pulmonary vasodilator activity in the rat.

Peroxynitrite (PN) worsens pathological conditions associated with oxidative stress. However, beneficial effects have also been reported. PN has been shown to demonstrate vasodilator as well as vasoconstrictor properties that are dependent upon the experimental conditions and the vascular bed studied. PN-induced vascular smooth muscle relaxation may involve the formation of nitric oxide (NO) donors. The present results show that PN has significant vasodilator activity in the pulmonary and systemic vascular beds, and that responses to PN were not attenuated by L-penicillamine (L-PEN), a PN scavenger, whereas responses to sodium nitroprusside (SNP) were decreased. PN had a small inhibitory effect on decreases in arterial pressure in response to the NO donors diethylammonium (Z)-1-(N,N-diethylamino)diazen-1-ium-1,2-diolate (DEA/NO) and S-nitrosoglutathione (GSNO). PN partially reversed hypoxic pulmonary vasoconstriction. PN responses were attenuated by the soluble guanylate cyclase (sGC) inhibitor, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) and responses to PN and the PN precursor, 3-morpholinosydnonimine (SIN-1), were different. These data show that PN has potent pulmonary vasodilator activity in the rat, and provide evidence that a PN interaction with S-nitrosothiols is not the major mechanism mediating the response. These data suggest that responses to PN are mediated by the activation of sGC, and that PN has a small inhibitory effect on NO responses.

Pulmonary and systemic vasodilator responses to the soluble guanylyl cyclase activator, BAY 60-2770, are not dependent on endogenous nitric oxide or reduced heme.

4-({(4-Carboxybutyl)[2-(5-fluoro-2-{[4'-(trifluoromethyl)biphenyl-4-yl]methoxy}phenyl)ethyl]amino}methyl)benzoic acid (BAY 60-2770) is a nitric oxide (NO)-independent activator of soluble guanylyl cyclase (sGC) that increases the catalytic activity of the heme-oxidized or heme-free form of the enzyme. In this study, responses to intravenous injections of the sGC activator BAY 60-2770 were investigated under baseline and elevated tone conditions induced by the thromboxane mimic U-46619 when NO synthesis was inhibited by N(ω)-nitro-L-arginine methyl ester hydrochloride (L-NAME), when sGC activity was inhibited by 1H-[1,2,4]-oxadizaolo[4,3]quinoxaline-1-one (ODQ), an agent that oxidizes sGC, and in animals with monocrotaline-induced pulmonary hypertension. The intravenous injections of BAY 60-2770 under baseline conditions caused small decreases in pulmonary arterial pressure, larger decreases in systemic arterial pressure, and no change or small increases in cardiac output. Under elevated tone conditions during infusion of U-46619, intravenous injections of BAY 60-2770 caused larger decreases in pulmonary arterial pressure, smaller decreases in systemic arterial pressure, and increases in cardiac output. Pulmonary vasodilator responses to BAY 60-2770 were enhanced by L-NAME or by ODQ in a dose that attenuated responses to the NO donor sodium nitroprusside. ODQ had no significant effect on baseline pressures and attenuated pulmonary and systemic vasodilator responses to the sGC stimulator BAY 41-8543 2-{1-[2-(fluorophenyl)methyl]-1H-pyrazolo[3,4-b]pyridin-3-yl}-5(4-morpholinyl)-4,6-pyrimidinediamine. BAY 60-2770 and sodium nitroprusside decreased pulmonary and systemic arterial pressures in monocrotaline-treated rats in a nonselective manner. The present data show that BAY 60-2770 has vasodilator activity in the pulmonary and systemic vascular beds that is enhanced by ODQ and NOS inhibition, suggesting that the heme-oxidized form of sGC can be activated in vivo in an NO-independent manner to promote vasodilation. These results show that BAY 60-2770 and sodium nitroprusside decreased pulmonary and systemic arterial pressures in monocrotaline-treated rats, suggesting that BAY 60-2770 does not have selective pulmonary vasodilator activity in animals with monocrotaline-induced pulmonary hypertension.

Pulmonary and systemic vasodilator responses to the soluble guanylyl cyclase stimulator, BAY 41-8543, are modulated by nitric oxide.

BAY 41-8543 is a nitric oxide (NO)-independent stimulator of soluble guanylyl cyclase (sGC). Responses to intravenous injections of BAY 41-8543 were investigated under baseline and elevated tone conditions and when NO synthase (NOS) was inhibited with N(ω)-nitro-L-arginine methyl ester (L-NAME). Under baseline conditions, intravenous injections of BAY 41-8543 caused small decreases in pulmonary arterial pressure, larger decreases in systemic arterial pressure, and increases in cardiac output. When pulmonary arterial pressure was increased to ∼30 mmHg with an intravenous infusion of U-46619, intravenous injections of BAY 41-8543 produced larger dose-dependent decreases in pulmonary arterial pressure, and the relative decreases in pulmonary and systemic arterial pressure in response to the sGC stimulator were similar. Treatment with L-NAME markedly decreased responses to BAY 41-8543 when pulmonary arterial pressure was increased to similar values (∼30 mmHg) in U-46619-infused and in U-46619-infused plus L-NAME-treated animals. The intravenous injection of a small dose of sodium nitroprusside (SNP) when combined with BAY 41-8543 enhanced pulmonary and systemic vasodilator responses to the sGC stimulator in L-NAME-treated animals. The present results indicate that BAY 41-8543 has similar vasodilator activity in the systemic and pulmonary vascular beds when pulmonary vasoconstrictor tone is increased with U-46619. These results demonstrate that pulmonary and systemic vasodilator responses to BAY 41-8543 are significantly attenuated when NOS is inhibited by L-NAME and show that vasodilator responses to BAY 41-8543 are enhanced when combined with a small dose of SNP in L-NAME-treated animals. The present results are consistent with the concept that pulmonary and systemic vasodilator responses to the sGC stimulator are NO-independent; however, the vasodilator activity of the compound is greatly diminished when endogenous NO production is inhibited with L-NAME. These data show that BAY 41-8543 has similar vasodilator activity in the pulmonary and systemic vascular beds in the rat.