Genetic gains with rapid-cycle genomic selection for combined drought and waterlogging tolerance in tropical maize (Zea mays L.).

Rapid cycle genomic selection (RC-GS) helps to shorten the breeding cycle and reduce the costs of phenotyping, thereby increasing genetic gains in terms of both cost and time. We implemented RC-GS on two multi-parent yellow synthetic (MYS) populations constituted by intermating ten elite lines involved in each population, including four each of drought and waterlogging tolerant donors and two commercial lines, with proven commercial value. Cycle 1 (C1 ) was constituted based on phenotypic selection and intermating of the top 5% of 500 S2 families derived from each MYS population, test-crossed and evaluated across moisture regimes. C1 was advanced to the next two cycles (C2 and C3 ) by intermating the top 5% selected individuals with high genomic estimated breeding values (GEBVs) for grain yield under drought and waterlogging stress. To estimate genetic gains, population bulks from each cycle were test-crossed and evaluated across locations under different moisture regimes. Results indicated that the realised genetic gain under drought stress was 0.110 t ha-1 yr-1 and 0.135 t ha-1 yr-1 , respectively, for MYS-1 and MYS-2. The gain was less under waterlogging stress, where MYS-1 showed 0.038 t ha-1 yr-1 and MYS-2 reached 0.113 t ha-1 yr-1 . Genomic selection for drought and waterlogging tolerance resulted in no yield penalty under optimal moisture conditions. The genetic diversity of the two populations did not change significantly after two cycles of GS, suggesting that RC-GS can be an effective breeding strategy to achieve high genetic gains without losing genetic diversity.

Convection enhanced delivery of panobinostat (LBH589)-loaded pluronic nano-micelles prolongs survival in the F98 rat glioma model.

BACKGROUND: The pan-histone deacetylase inhibitor panobinostat is a potential therapy for malignant glioma, but it is water insoluble and does not cross the blood-brain barrier when administered systemically. In this article, we describe the in vitro and in vivo efficacy of a novel water-soluble nano-micellar formulation of panobinostat designed for administration by convection enhanced delivery (CED). MATERIALS AND METHODS: The in vitro efficacy of panobinostat-loaded nano-micelles against rat F98, human U87-MG and M059K glioma cells and against patient-derived glioma stem cells was measured using a cell viability assay. Nano-micelle distribution in rat brain was analyzed following acute CED using rhodamine-labeled nano-micelles, and toxicity was assayed using immunofluorescent microscopy and synaptophysin enzyme-linked immunosorbent assay. We compared the survival of the bioluminescent syngenic F98/Fischer344 rat glioblastoma model treated by acute CED of panobinostat-loaded nano-micelles with that of untreated and vehicle-only-treated controls. RESULTS: Nano-micellar panobinostat is cytotoxic to rat and human glioma cells in vitro in a dose-dependent manner following short-time exposure to drug. Fluorescent rhodamine-labelled nano-micelles distribute with a volume of infusion/volume of distribution (Vi/Vd) ratio of four and five respectively after administration by CED. Administration was not associated with any toxicity when compared to controls. CED of panobinostat-loaded nano-micelles was associated with significantly improved survival when compared to controls (n=8 per group; log-rank test, P<0.001). One hundred percent of treated animals survived the 60-day experimental period and had tumour response on post-mortem histological examination. CONCLUSION: CED of nano-micellar panobinostat represents a potential novel therapeutic option for malignant glioma and warrants translation into the clinic.

Convection-enhanced delivery of MANF--volume of distribution analysis in porcine putamen and substantia nigra.

Mesencephalic astrocyte-derived neurotrophic factor (MANF) is a 20kDa human protein which has both neuroprotective and neurorestorative activity on dopaminergic neurons and therefore may have application for the treatment of Parkinson's Disease. The aims of this study were to determine the translational potential of convection-enhanced delivery (CED) of MANF for the treatment of PD by studying its distribution in porcine putamen and substantia nigra and to correlate histological distribution with co-infused gadolinium-DTPA using real-time magnetic resonance imaging. We describe the distribution of MANF in porcine putamen and substantia nigra using an implantable CED catheter system using co-infused gadolinium-DTPA to allow real-time MRI tracking of infusate distribution. The distribution of gadolinium-DTPA on MRI correlated well with immunohistochemical analysis of MANF distribution. Volumetric analysis of MANF IHC staining indicated a volume of infusion (Vi) to volume of distribution (Vd) ratio of 3 in putamen and 2 in substantia nigra. This study confirms the translational potential of CED of MANF as a novel treatment strategy in PD and also supports the co-infusion of gadolinium as a proxy measure of MANF distribution in future clinical studies. Further study is required to determine the optimum infusion regime, flow rate and frequency of infusions in human trials.

Convection-enhanced delivery of AAV2 in white matter--a novel method for gene delivery to cerebral cortex.

BACKGROUND: Convection-enhanced delivery (CED) is currently under investigation for delivering therapeutic agents to subcortical targets in the brain. Direct delivery of therapies to the cerebral cortex, however, remains a significant challenge. NEW METHOD: We describe a novel method of targeting adeno-associated viral vector (AAV) mediated gene therapies to specific cerebral cortical regions by performing high volume, high flow rate infusions into underlying white matter in a large animal (porcine) model. RESULTS: Infusion volumes of up to 700 µl at flow rates as high as 10 µl/min were successfully performed in white matter without adverse neurological sequelae. Co-infusion of AAV2/5-GFP with 0.2% Gadolinium in artificial CSF confirmed transgene expression in the deep layers of cerebral cortex overlying the infused areas of white matter. COMPARISON WITH EXISTING METHODS: AAV-mediated gene therapies have been previously targeted to the cerebral cortex by performing intrathalamic CED and exploiting axonal transport. The novel method described in this study facilitates delivery of gene therapies to specific regions of the cerebral cortex without targeting deep brain structures. CONCLUSIONS: AAV-mediated gene therapies can be targeted to specific cortical regions by performing CED into underlying white matter. This technique could be applied to the treatment of neurological disorders characterised by cerebral cortical degeneration.

In vitro and in vivo testing of a novel recessed-step catheter for reflux-free convection-enhanced drug delivery to the brain.

INTRODUCTION: The optimisation of convection-enhanced drug delivery (CED) to the brain is fundamentally reliant on minimising drug reflux. The aim of this study was to evaluate the performance of a novel reflux-resistant CED catheter incorporating a recessed-step and to compare its performance to previously described stepped catheters. METHODS: The in vitro performance of the recessed-step catheter was compared to a conventional "one-step" catheter with a single transition in outer diameter (OD) at the catheter tip, and a "two-step" design comprising two distal transitions in OD. The volumes of distribution and reflux were compared by performing infusions of Trypan blue into agarose gels. The in vivo performance of the recessed-step catheter was then analysed in a large animal model by performing infusions of 0.2% Gadolinium-DTPA in Large White/Landrace pigs. RESULTS: The recessed-step catheter demonstrated significantly higher volumes of distribution than the one-step and two-step catheters (p=0.0001, one-way ANOVA). No reflux was detected until more than 100 ul had been delivered via the recessed-step catheter, whilst reflux was detected after infusion of only 25 ul via the 2 non-recessed catheters. The recessed-step design also showed superior reflux resistance to a conventational one-step catheter in vivo. Reflux-free infusions were achieved in the thalamus, putamen and white matter at a maximum infusion rate of 5 ul/min using the recessed-step design. CONCLUSION: The novel recessed-step catheter described in this study shows significant potential for the achievement of predictable high volume, high flow rate infusions whilst minimising the risk of reflux.

Robot-guided convection-enhanced delivery of carboplatin for advanced brainstem glioma.

BACKGROUND: Patients with diffuse intrinsic pontine glioma (DIPG) have a poor prognosis with median survival reported as 9 months. The failure of systemic chemotherapy to improve prognosis may be due to inadequate penetration of the blood-brain barrier (BBB). Convection-enhanced delivery (CED) has the potential to improve outcomes by facilitating bypass of the BBB. We describe the first use of carboplatin for the treatment of advanced DIPG using a robot-guided catheter implantation technique. METHODS: A 5-year-old boy presented with a pontine mass lesion. The tumor continued to progress despite radiotherapy. Using an in-house modification to neuroinspire stereotactic planning software (Renishaw Plc., Gloucestershire, UK), the tumor volume was calculated as 43.6 ml. A transfrontal trajectory for catheter implantation was planned facilitating the in-house manufacture of a recessed-step catheter. The catheter was implanted using a neuromate robot (Renishaw Plc., Gloucestershire, UK). The initial infusion of carboplatin (0.09 mg/ml) was commenced with real-time T2-weighted MRI, facilitating estimation of the volume of infusate distribution. Infusions were repeated on a total of 5 days. RESULTS: The catheter implantation and infusions were well tolerated. A total volume of 49.8 ml was delivered over 5 days. T2-weighted MRI on completion of the final infusion demonstrated signal change through a total volume of 35.1 ml, representing 95 % of the targeted tumor volume. Follow-up at 4 weeks revealed clinical signs of improvement and increased T2 signal change throughout the volume of distribution. However, there was tumor progression in the regions outside the volume of distribution. CONCLUSIONS: This case demonstrates the feasibility of accurately and safely delivering small-diameter catheters to the brainstem using a robot-guided implantation procedure, and real-time MRI tracking of infusate distribution.

Intermittent convection-enhanced delivery to the brain through a novel transcutaneous bone-anchored port.

Convection-enhanced delivery (CED) describes a novel method of drug delivery to the brain through intraparenchymal microcatheters. One of the barriers to effective translation of CED to clinical trials is the requirement for intermittent delivery over prolonged periods. This is particularly relevant for delivery of neurotrophins for the treatment of Parkinson's disease where chronic infusion of glial cell-line derived neurotrophic factor (GDNF) with subcutaneously implanted pumps has been associated with poor distribution and local toxicity due to point source accumulation. We have previously described the development of an implantable catheter for CED which facilitates repeated drug administrations at intervals of up to one month. The aim of this study was to determine the feasibility of implanting a transcutaneous bone-anchored port (TBAP) which facilitates chronic intermittent drug delivery to the brain. We describe the design and development of a titanium port which was implanted in Large White and NIH miniature pigs for periods of up to three months. By intermittently accessing the port with a needle administration set it was possible to repeatedly perform CED infusions at one month intervals. This study confirms the safety and feasibility of performing intermittent CED through a transcutaneous bone-anchored port. The use of a transcutaneous port has the potential to facilitate clinical translation of CED of therapeutics requiring intermittent delivery to achieve optimum efficacy whilst negating the need for subcutaneously implanted pumps.

The development of an implantable catheter system for chronic or intermittent convection-enhanced delivery.

Convection-enhanced delivery (CED) is a promising technique for the administration of therapeutic agents such as cytotoxics, neurotrophins and enzymes to the brain. In this study we describe the development of an implantable catheter system that is compatible with long-term intermittent CED. Catheters made from fused silica, PEEK or carbothane, and of various internal and external diameters were implanted in the striatum of rats and assessed for patency at 21 or 28 days. A high-rate of catheter blockage was observed with all fused silica and PEEK catheters. Carbothane catheters with an outer diameter of 0.6mm and an inner diameter of 0.35 mm had significantly lower rates of blockage (P≤0.01). Carbothane catheters were then implanted into 4 Large White/Landrace pigs and 4 NIH miniature pigs and infusions undertaken at monthly intervals to evaluate catheter patency and infusate distribution. Catheter patency was demonstrated for a maximum period of 163 days in one animal. Widespread and reproducible intraputamenal CED could be achieved with intermittent drug delivery at flow-rates as high as 5 µl/min. Problems were encountered using the pig model due to catheter distortion from rapid animal growth. In conclusion, it is possible to achieve intermittent high-flow CED with a chronic implanted carbothane catheter with a low rate of catheter blockage.

Carlinoside reduces hepatic bilirubin accumulation by stimulating bilirubin-UGT activity through Nrf2 gene expression.

Accumulation of bilirubin, primarily because of its insolubility, has been found to be associated with liver diseases including jaundice. Free bilirubin is insoluble; its glucuronidation by bilirubin-UGT enzyme (UGT1A1) makes it soluble and eliminates it through urine and faeces. Taking CCl(4) induced rat liver dysfunction model, we demonstrated that suppression of UGT1A1 activity in rat liver increased serum bilirubin level which could be reversed by carlinoside (Cln), a flavone glycoside. Although Cln is a flavone compound, it escaped self-glucuronidation in the intestine and readily absorbed. Kinetic study of microsomal UGT1A1 from HepG2 cells suggested that Cln enhanced enzyme activity by increasing V(max) without altering K(m). This altered V(max) was found to be due to UGT1A1 overexpression by Cln which was observed in both HepG2 and rat primary hepatocytes. Since Nrf2 is the transcription factor of UGT1A1, we examined whether Cln effect on UGT1A1 overexpression is mediated through Nrf2. In Nrf2 knock-out cells, Cln could not elevate UGT1A1 activity indicating Nrf2 to be its target. Cln significantly increased Nrf2 gene expression in HepG2 cells which was subsequently localized in nuclear region. Results from ChIP assay showed that Cln markedly augmented Nrf2 binding to UGT1A1 promoter that consequently enhanced reporter activity. Our findings therefore show that Cln upregulated Nrf2 gene expression, increased its nuclear translocation and stimulated UGT1A1 promoter activity. Total outcome of these events brought about a significant increase of bilirubin glucuronidation. Cln therefore could be a worthy choice to intervene hyperbilirubinemia due to liver dysfunction.

Case series of post-thrombolysis patients undergoing hemicraniectomy for malignant anterior circulation ischaemic stroke.

While ischaemic stroke remains a leading cause of death and disability, there have been recent advancements in treatment modalities including thrombolysis and decompressive hemicraniectomy. A retrospective review of patients treated in our NHS teaching hospital, in Plymouth (UK), over a 2 year period identified 17 thrombolysed patients, of whom two had undergone subsequent decompressive hemicraniectomy. These were non-dominant hemisphere strokes in young patients, aged 51 and 57. Initial NIHSS scores were 16 and 17, and they received thrombolysis at 2 hrs 42 min and 5 hrs 10 min post onset of symptoms respectively. CT imaging demonstrated cerebral swelling with significant midline shift in both cases, and decompressive hemicraniectomy was undertaken at 29 hrs 8 min and 27 hrs 30 min post-thrombolysis. We found no significant intra-operative complications attributable to prior use of thrombolytics. Both patients have had acceptable psychological and physical outcomes, with Barthel Index scores of 40 and 25, and MMSE scores of 29/30 and 27/30. We conclude that the use of thrombolytic therapy does not contra-indicate subsequent decompressive hemicraniectomy in well selected patients with non-dominant hemisphere strokes. More research in this field is required to elucidate factors which would facilitate recognition of stroke patients who will benefit most from aggressive medical and neurosurgical intervention.

The use of mobile computed tomography in intensive care: regulatory compliance and radiation protection.

The use of mobile head computed tomography (CT) equipment in intensive care is of benefit to unstable patients with brain injury. However, ionising radiation in a ward environment presents difficulties due to the necessity to restrict the exposure to staff and members of the public according to regulation 8(1-2) of the Ionising Radiation Regulations 1999. The methodology for enabling the use of a mobile head CT unit in an open ward area is discussed and a practical solution given. This required the reduction in scatter doses through the installation of extra internal and external shielding, and a further reduction in annual scatter dose by restricting the use of the equipment based on a simulation of the annual ward workload.

Single-stage posterior transpedicular approach for circumferential epidural decompression and three-column stabilization using a titanium cage for upper thoracic spine neoplastic disease: a case series and technical note.

Two or three-column neoplastic spinal disease requiring circumferential decompression and instrumented stabilization is commonly treated through combined anterior transcavitary and posterior surgical approaches. An alternative approach advocated in the literature is costotransversectomy and interbody cage insertion. The authors present an effective and less invasive treatment paradigm using a single-stage posterior transpedicular approach (TPA) to circumferential thoracic decompression and fixation, avoiding the morbidity of thoracic or thoraco-abdominal access based on a series of eight patients with upper thoracic neoplastic disease.

Gnathostomiasis of the anterior chamber.

Ocular involvement with Gnathostoma spinigerum occurs years after the initial infection that is acquired by ingestion of poorly cooked, pickled seafood or water contaminated with third stage larvae. Here we report a case of gnathostomiasis of the left eye of a 32-year-old lady hailing from Meghalaya, India. Her vision had deteriorated to hand movement. Slit lamp examination revealed a live, actively motile worm in the anterior chamber, which was extracted by supra temporal limbal incision and visual acuity was restored.

Loa loa in the anterior chamber of the eye: a case report.

An unusual case of loiasis from Assam is reported here. Loa loa is a subcutaneous filarial parasite of man and is transmitted to humans by chrysops flies. The patient presented with foreign body sensation and visual disturbances of the right eye. Examination revealed a white coiled structure in the cornea. Routine blood and other investigations were within normal limits. A live adult worm was extracted and identity was confirmed by microscopy to be Loa loa. Patient was treated with diethylcarbamazine and steroid. We found this case interesting as the worm was present in the anterior chamber--an unusual site and there were no other positive findings besides the lone worm.

Synthesis, absolute stereochemistry and molecular design of the new antifungal and antibacterial antibiotic produced by Streptomyces sp.201.

The absolute stereochemistry of the new antifungal and antibacterial antibiotic produced by Streptomyces sp.201 has been established by achieving the total synthesis of the product. A series of analogues have also been synthesized by changing the side chain and their bioactivity assessed against different microbial strains. Among them, 1e (R = C8H17) was found to be the most potent with MIC of 8 microg/mL against Mycobacterium tuberculosis, 12 microg/mL against Escherichia coli and 16 microg/mL against Bacillus subtilis 6 microg/mL against Proteus vulgaris. This was followed by 1b (R = C5H11) with MIC of 10-20 microg/mL range and 1d (R = C7H15) with MIC of 14-24 g/mL, whereas 1a (R = C4H9) and 1f (R = C18H35) were found to be completely inactive. Besides, 1c (R = C6H13) showed certain extent of antibacterial activity in the range of 24-50 microg/mL. Mycobacterium tuberculosis was very sensitive to 1e (R = C8H17) with MIC of 8 microg/mL. Antifungal activity of analogues 1d (R = C7H15) and 1e, (R = C8H17) against Fusarium oxysporum and Rhizoctonia solani were found promising with MFCs in the 15-18 microg/mL range.

Intraarterial 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and systemic chemotherapy for malignant gliomas: a follow-up study.

Twenty-five adults who harbored malignant gliomas received 72 courses of intraarterial 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) (100 mg/m2) and 67 courses of systemic vincristine (1.0 mg/m2) and procarbazine (100 mg/m2) as induction therapy (BVP) followed by 106 courses of systemic 1-(2-chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea (methyl-CCNU) (130 mg/m2), vincristine, and procarbazine as maintenance therapy (MVP). With a 6-week interval between each treatment, the median and range for the number of courses of BVP were 3 and 1 to 4 and those for MVP were 3 and 0 to 14, respectively. Fifteen patients (60%) responded to both BVP and MVP, and 10 (40%) did not. The overall median survival time was 12.7 months (range, 1.8 to 48.5+ months). Two of 3 patients who had recurrent gliomas responded and survived for 37+ to 45+ months. Seven of 10 who had nonirradiated glioblastomas responded and survived for 9 to 22 months. Four who had nonirradiated anaplastic astrocytomas all responded and survived for 38+ to 48.5+ months. Two who also received radiotherapy (1 glioblastoma and 1 primitive neuroectodermal tumor) benefited and survived for 16.9 and 28.5+ months. All who did not respond favorably died within 8 months. During the infusion of BCNU, complications included transient orbital and head pain, periorbital and scleral erythema in all patients, and a focal seizure in 1 (4%). During the 6-month induction periods, leukopenia and thrombocytopenia occurred in 1 (4%), deep vein thrombosis occurred in 9 (36%), pulmonary emboli occurred in 8 (32%), upper respiratory infections occurred in 6 (24%), pneumonia occurred in 9 (36%), and herpes zoster occurred in 1 (4%).(ABSTRACT TRUNCATED AT 250 WORDS)

Fibrosarcoma of the mediastinum.

Fibrosarcoma is a rare primary malignant tumor of the mediastinum. Three cases are presented with different presenting symptoms and clinical manifestations. Thoracotomy with biopsy of the mass is the only method for arriving at a definitive histologic diagnosis.