Dual Recycling of Depolymerization Catalyst and Biodegradable Polyester that Markedly Outperforms Polyolefins.

Chemically recyclable, circular polymers continue to attract increasing attention, but rendering both catalysts for depolymerization and high-performance polymers recyclable is a more sustainable yet challenging goal. Here we introduce a dual catalyst/polymer recycling system in that recyclable inorganic phosphomolybdic acid catalyzes selective depolymerization of high-ceiling-temperature biodegradable poly(δ-valerolactone) in bulk phase, which, upon reaching suitable molecular weight, exhibits outstanding mechanical performance with a high tensile strength of ≈66.6 MPa, fracture strain of ≈904 %, and toughness of ≈308 MJ m-3 , and thus markedly outperforms commodity polyolefins, recovering its monomer in pure state and quantitative yield at only 100 °C. In sharp contrast, the uncatalyzed depolymerization not only requires a high temperature of >310 °C but is also low yielding and non-selective. Importantly, the recovered monomer can be repolymerized as is to reproduce the same polymer, thereby closing the circular loop, and the recycled catalyst can be reused repeatedly for depolymerization runs without loss of its catalytic activity and efficiency.

Chemically circular, mechanically tough, and melt-processable polyhydroxyalkanoates.

Polyhydroxyalkanoates (PHAs) have attracted increasing interest as sustainable plastics because of their biorenewability and biodegradability in the ambient environment. However, current semicrystalline PHAs face three long-standing challenges to broad commercial implementation and application: lack of melt processability, mechanical brittleness, and unrealized recyclability, the last of which is essential for achieving a circular plastics economy. Here we report a synthetic PHA platform that addresses the origin of thermal instability by eliminating α-hydrogens in the PHA repeat units and thus precluding facile cis-elimination during thermal degradation. This simple α,α-disubstitution in PHAs enhances the thermal stability so substantially that the PHAs become melt-processable. Synergistically, this structural modification also endows the PHAs with the mechanical toughness, intrinsic crystallinity, and closed-loop chemical recyclability.

Consequence of cyclic pollen selection for heat tolerance on the performance of different generations in maize (Zea mays L.).

The reproductive stage in many crops, including maize, is very sensitive to heat stress and the genetic overlap between gametophytic and sporophytic phase gives an opportunity to select superior stress tolerant genotype at gametophytic stage. An attempt was made to evaluate the response of cyclic pollen selection in the F1 and F2 generations on the performance of F3 generation progenies for seed yield and yield contributing traits under natural heat stress conditions. In this direction three groups of F3 progenies, namely (i) pollen selection in F1 and F2 generations (GG), (ii) pollen selection only in F2 generation (CG), (iii) no pollen selection in F1 and F2 generations (CC) were screened for heat stress at Agricultural Research Station (ARS), Bheemarayanagudi. The GG progenies recorded significantly higher chlorophyll content, more number of pollen grains per anther and less pollen sterility compared to CG and CC group of progenies under heat stress. Further, the F4 progenies obtained through cyclic pollen selection (in F1, F2 and F3) were also tested for heat stress tolerance at seedling stage. The significant improvement for heat stress tolerance was recorded in F4 progenies derived through cyclic pollen selection as compared to control (no pollen selection for heat tolerance in any generation) F4 progenies. The results indicated that cyclic pollen selection in F1, F2 and F3 generations improved the heat stress tolerance of the progenies in the succeeding generations. To provide genetic evidence for the effect of pollen selection for heat tolerance, the control F2 (C) and selected F2 (G) populations were compared for the segregation of SSR markers. The selected F2 (G) population showed significant deviation from normal Mendelian ratio of 1:2:1 and showed skewness towards the alleles selected from male parent. The results provide strong evidence for an increase in the frequency of parental alleles in the progenies that impart heat stress tolerance.

Comparison of Clinical Efficacy of Classical Inferior Alveolar Nerve Block and Vazirani-Akinosi Technique in Bilateral Mandibular Premolar Teeth Removal: A Split-Mouth Randomized Study.

Purpose: To compare the clinical efficacy of classical inferior alveolar nerve block (CIANB) and Vazirani-Akinosi (VA) injection technique in patients indicated for bilateral mandibular premolar teeth extraction for orthodontic treatment. Methods: This split-mouth comparative study was conducted on 20 patients randomly selected for bilateral extraction of mandibular premolar indicated for orthodontic treatment to receive CIANB and VA injection technique alternatively. The clinical parameters evaluated were pain during injection, onset of anesthesia, duration of anesthesia, quality of anesthesia, nerve anesthetized with single nerve block, need for re-injection and frequency of positive aspiration. Results: No statistically significant differences were observed regarding the onset of anesthesia, duration of anesthesia, quality of anesthesia, nerves anesthetized with single nerve block and need for re-injection. However, pain experienced during injection was statistically significant and was lesser in VA technique than CIANB. Positive aspiration was not found in both the injection techniques. Conclusion: VA technique showed a statistically significant difference in terms of less pain experienced during injection than CIANB. However, though not significant, VA technique was more clinically superior over the CIANB in terms of duration of anesthesia, quality of anesthesia and the need for re-injection. Also in this study, there were no complications associated with any of the injection techniques and the prevalence of positive aspiration was not found in both the techniques.

Pseudomonas syringae pv. phaseolicola Uses Distinct Modes of Stationary-Phase Persistence To Survive Bacteriocin and Streptomycin Treatments.

Antimicrobial treatment of bacteria often results in a small population of surviving tolerant cells, or persisters, that may contribute to recurrent infection. Antibiotic persisters are metabolically dormant, but the basis of their persistence in the presence of membrane-disrupting biological compounds is less well understood. We previously found that the model plant pathogen Pseudomonas syringae pv. phaseolicola 1448A (Pph) exhibits persistence to tailocin, a membrane-disrupting biocontrol compound with potential for sustainable disease control. Here, we compared physiological traits associated with persistence to tailocin and to the antibiotic streptomycin and established that both treatments leave similar frequencies of persisters. Microscopic profiling of treated populations revealed that while tailocin rapidly permeabilizes most cells, streptomycin treatment results in a heterogeneous population in the redox and membrane permeability state. Intact cells were sorted into three fractions according to metabolic activity, as indicated by a redox-sensing reporter dye. Streptomycin persisters were cultured from the fraction associated with the lowest metabolic activity, but tailocin persisters were cultured from a fraction associated with an active metabolic signal. Cells from culturable fractions were able to infect host plants, while the nonculturable fractions were not. Tailocin and streptomycin were effective in eliminating all persisters when applied sequentially, in addition to eliminating cells in other viable states. This study identifies distinct metabolic states associated with antibiotic persistence, tailocin persistence, and loss of virulence and demonstrates that tailocin is highly effective in eliminating dormant cells.IMPORTANCE Populations of genetically identical bacteria encompass heterogeneous physiological states. The small fraction of bacteria that are dormant can help the population survive exposure to antibiotics and other stresses, potentially contributing to recurring infection cycles in animal or plant hosts. Membrane-disrupting biological control treatments are effective in killing dormant bacteria, but these treatments also leave persister-like survivors. The current work demonstrates that in Pph, persisters surviving treatment with membrane-disrupting tailocin proteins have an elevated redox state compared to that of dormant streptomycin persisters. Combination treatment was effective in killing both persister types. Culturable persisters corresponded closely with infectious cells in each treated population, whereas the high-redox and unculturable fractions were not infectious. In linking redox states to heterogeneous phenotypes of tailocin persistence, streptomycin persistence, and infection capability, this work will inform the search for mechanisms and markers for each phenotype.

Induction of pre-chorismate, jasmonate and salicylate pathways by Burkholderia sp. RR18 in peanut seedlings.

AIMS: To characterize the mechanisms by which bacteria in the peanut rhizosphere promote plant growth and suppress Aspergillus niger, the fungus that causes collar rot of peanut. METHODS AND RESULTS: In all, 131 isolates cultured from the peanut rhizosphere were assayed for growth promotion in a seedling germination assay. The most effective isolate, RR18, was identified as Burkholderia sp. by 16S sequencing analysis. RR18 reduced collar rot disease incidence and increased the germination rate and biomass of peanut seeds, and had broad-spectrum antifungal activity. Quantitative analyses showed that RR18 induced long-lasting accumulation of jasmonic acid, salicylic acid and phenols, and triggered the activity of six defence enzymes related to these changes. Comparative proteomic analysis of treated and untreated seedlings revealed a clear induction of four abundant proteins, including a member of the pre-chorismate pathway, a regulator of clathrin-coated vesicles, a transcription factor and a hypothetical protein. CONCLUSION: Burkholderia sp. RR18 promotes peanut growth and disease resistance, and stably induces two distinct defence pathways associated with systemic resistance. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates that a strain of the Burkholderia cepacia complex can elicit both salicylic- and jasmonic-acid-mediated defences, in addition to having numerous other beneficial properties.

Genome Mining Shows Ubiquitous Presence and Extensive Diversity of Toxin-Antitoxin Systems in Pseudomonas syringae.

Bacterial toxin-antitoxin (TA) systems consist of two or more adjacent genes, encoding a toxin and an antitoxin. TA systems are implicated in evolutionary and physiological functions including genome maintenance, antibiotics persistence, phage defense, and virulence. Eight classes of TA systems have been described, based on the mechanism of toxin neutralization by the antitoxin. Although studied well in model species of clinical significance, little is known about the TA system abundance and diversity, and their potential roles in stress tolerance and virulence of plant pathogens. In this study, we screened the genomes of 339 strains representing the genetic and lifestyle diversity of the Pseudomonas syringae species complex for TA systems. Using bioinformatic search and prediction tools, including SLING, BLAST, HMMER, TADB2.0, and T1TAdb, we show that P. syringae strains encode 26 different families of TA systems targeting diverse cellular functions. TA systems in this species are almost exclusively type II. We predicted a median of 15 TA systems per genome, and we identified six type II TA families that are found in more than 80% of strains, while others are more sporadic. The majority of predicted TA genes are chromosomally encoded. Further functional characterization of the predicted TA systems could reveal how these widely prevalent gene modules potentially impact P. syringae ecology, virulence, and disease management practices.

Medium term results following heart transplantation for end stage heart failure: A single center experience of 257 patients.

OBJECTIVE: End stage heart failure is a lethal disease with a dismal 5 year survival. Heart transplantation has proven to be a highly effective modality of treatment in appropriately selected group of such patients. This is a retrospective analysis of medium term outcomes of heart transplantation in the setting of a private health facility in India. The objective of this study was two fold. METHODS: The outcome of 257 heart transplants done at a single centre from October 2012 to October 2019 was analyzed. Patients with combined Heart and lung transplants and those whose complete medical records were unavailable were excluded from the study. Survival was tracked at 60 days, 90 days, one year and beyond for a maximum of 7 years. Preoperative patient risk profiles were characterized on the basis of INTERMACS category. RESULTS: There were 176 male and 81 female patients. The age range was from 8 months to 78 years with a mean of 32.9 years. Survival at 2 months was 87%, at 90 days was 83%, at one year was 81%, 2 years was 75%, at 3 years was 72% and at 5 years and beyond was 62% for the whole series. Strong predictors of 90 day mortality included INTERMACS category (odd's ratio 0.289, p = 0.000) and creatinine more than 1.5 mg/dl (odd's ratio 2.48, p = 0.056). Recipient pulmonary vascular resistance and donor organ ischemic times were not found to be statistically significant factors affecting outcome. Medium term survival was influenced by INTERMACS category (Hazard ratio > 3 for INTERMACS category 1 compared to INTERMACS 4 or 5, p < 0.0001) and creatinine > 1.5 mg/dl (Hazard ratio 2.15, p = 0.003). This effect of creatinine was related to the age of the recipient. Hazard ratio 1.4, p = 0.524 if age <30 and Hazard ratio 4.78, p = 0.006, if age was >50. CONCLUSION: Satisfactory medium term outcome is possible after heart transplantation even in resource constrained environment of a developing country.

Intra-Arterial Chemotherapy for Retinoblastoma: Four-Year Results from Tertiary Center in India.

BACKGROUND: There are limited reports of intra-arterial chemotherapy (IAC) for retinoblastoma (RB) from developing world. OBJECTIVES: In this study, we report our 4-year experience of IAC for RB from India. METHODS: Retrospective, interventional case series. Primary outcome measures included tumor regression, vitreous seeds and subretinal seeds control, and globe salvage. Secondary outcome measures were best-corrected visual acuity and treatment complications. RESULTS: Fifteen eyes underwent 53 IAC procedures over mean 28.6 ± 13.8 months (range 10-51 months). IAC was employed as primary (n = 6) or secondary (n = 9) chemotherapy. Following IAC, complete regression of main tumor was seen in 7 eyes (47%) and partial regression in 3 (20%) eyes. Enucleation was done in 5(33%) eyes. Globe salvage rates were achieved in 1 eye (100%) in group B, 2 eyes (67%) in group C (n = 3), 6 eyes (67%) in group D (n = 9), and 1 eye (50%) in group E (n = 2). Following IAC, Kaplan-Meier survival curve showed 93% globe survival rate at 1 year, 76% at 2 years, and 66% at 3, and 4 years. CONCLUSION: IAC has enhanced globe salvage rates in eyes with RB. Multicenter studies with longer follow-up are necessary to better understand outcomes in the long term.

Effect of footplate neuromuscular electrical stimulation on functional and quality-of-life parameters in patients with peripheral artery disease: pilot, and subsequent randomized clinical trial.

BACKGROUND: Supervised exercise programmes for intermittent claudication have poor access and limited compliance. Neuromuscular electrical stimulation (NMES) may be an effective alternative. A proof-of-concept study and RCT were conducted. METHODS: In study 1, eligible patients underwent baseline assessment; treadmill testing for initial (ICD) and maximum (MCD) claudication distance; EuroQoL Five Dimensions five-level instrument (EQ-5D-5L™) and Intermittent Claudication Questionnaire (ICQ) assessment; and measurement of ultrasound haemodynamics of the superficial femoral artery. After familiarization with the NMES device, participants underwent a 30-min session of stimulation with concomitant recording of haemodynamic measures at 15 min, and after device cessation. Measurements were repeated after 6 weeks of daily use of NMES. In study 2, consecutive patients underwent baseline assessment before online randomization to a supervised exercise programme only, or adjunctive NMES treatment for 6 weeks, followed by repeat measurements. RESULTS: Study 1 (20 patients) showed a significant improvement in MCD (46 per cent; P < 0·001) and ICD (71 per cent; P < 0·001). The RCT (42 patients) showed a significant adjunctive benefit of NMES in ICD (46 per cent; P = 0·014). Improvements were seen in the ICQ (9 points; P = 0·009) and EQ-5D-5L™ (P = 0·007) in study 1, and there was a significant adjunctive benefit of NMES on the ICQ score in patients who did supervised exercise (11·2 points; P = 0·031). Blood volume flow and time-adjusted mean velocity increased significantly with the device on (P < 0·050). Overall, NMES compliance exceeded 95 per cent. CONCLUSION: Footplate NMES significantly improved walking distance in patients with intermittent claudication when used independently and also as an adjunct to supervised exercise. Registration number: trial 1, NCT02436200; trial 2, NCT02429310 (http://www.clinicaltrials.gov).

ANTECEDENTES: Los programas de ejercicio supervisado (supervised exercise programmes, SEP) para la claudicación intermitente (intermittent claudication, IC) tienen un acceso y un cumplimiento deficientes. La estimulación eléctrica neuromuscular (neuromuscular electrical stimulation, NMES) puede ser una alternativa clínicamente efectiva. Se realizó un estudio de prueba de concepto y un ensayo controlado aleatorizado. MÉTODOS: Estudio 1: Veinte pacientes elegibles se sometieron a una evaluación inicial que incluía una prueba en la cinta de correr para la distancia inicial de claudicación (initial claudication distance, ICD) y la distancia máxima de claudicación (maximum claudication distance, MCD), EuroQoL-5D (EQ-5D), valoración mediante el cuestionario de claudicación intermitente (intermittent claudication questionnaire, ICQ), y hemodinámica por ecografía de la arteria femoral superficial. Después de familiarizarse con el dispositivo NMES, los participantes se sometieron a una sesión de estimulación de 30 minutos con el registro concomitante de medidas hemodinámicas a los 15 minutos y después del cese del dispositivo. Se realizaron mediciones repetidas después de 6 semanas de uso diario de NMES. Estudio 2: Se reclutaron 42 pacientes que tras una evaluación inicial y posterior aleatorización al azar en línea, se asignaron al Grupo A, utilizando SEP solamente; o al el Grupo B, con tratamiento NMES complementario durante 6 semanas seguido de medidas repetidas. RESULTADOS: El estudio 1 mostró una mejoría significativa de la MCD (46%, P < 0,0001) y de la ICD (71%, P < 0.004). El ensayo clínico mostró un beneficio coadyuvante significativo de NMES en la ICD (46%, P = 0,014). Se observaron mejorías en la puntuación del ICQ (9 puntos, P < 0,01) y del EQ-5D (P < 0,05) en el estudio 1, con un beneficio coadyuvante significativo de NMES en la puntuación del ICQ (11 puntos, P < 0,05). El flujo de volumen de sangre (CC/min) y TAMV (cm/s) aumentaron significativamente con el dispositivo en funcionamiento (P < 0,05). El cumplimiento global de la NMES superó el 95%. CONCLUSIÓN: La plataforma de NMES para el pie mejora significativamente las distancias de caminar en la claudicación intermitente cuando se usa de forma independiente y también proporciona un beneficio complementario al ejercicio supervisado en la distancia caminada sin dolor. La mejora del flujo sanguíneo puede ser un mecanismo para explicar estos resultados.

Regioselective Hydrogenation of Itaconic Acid to γ-Isovalerolactone by Transition-Metal Nanoparticle Catalysts.

Current methods for hydrogenation of bio-derived itaconic acid (IA) lead to a mixture of isomeric lactone products. Transition-metal nanoparticles (TM-NPs), in situ-generated through thermolysis of TM(0) (Ru, Fe, W, Cr) carbonyls, in particular Ru-NPs, were found to catalyze regioselective hydrogenation of IA by syngas (2 H2 /CO) into γ-isovalerolactone (GiVL) in approximately 70 % isolated yield. Key sustainability features of this new route include: a one-pot direct transformation of bio-renewable IA into value-added GiVL selectively, use of inexpensive and renewable syngas in aqueous solution, and development of a supported recyclable NP catalyst system, Al2 O3 -Ru-NPs.

Imaging in a rare case of intramuscular angioleiomyoma around the knee joint.

Angioleiomyoma are rare benign tumors originating from smooth muscles of veins. They are found more commonly in extremities and are seen in subcutaneous tissue. Intramuscular angioleiomyoma is rare and can be confused with hemangioma. Though they do not have any characteristic imaging features but they should be considered in the differential diagnosis due to certain specific imaging findings on MRI which are discussed in this article.

Remodeling of Neocondyle.

Temporomandibular joint (TMJ) ankylosis in children is one of the most complex and challenging problems managed by oral and maxillofacial surgeons. TMJ ankylosis in growing children often leads to facial deformity, difficulty in chewing and swallowing, severe malocclusion, poor oral hygiene, multiple decayed teeth, and impairment of speech. A good functional and esthetic outcome can be achieved after reconstruction with the autogenous grafts. Here, we present a case of a 9-year-old patient treated with condylectomy and ipsilateral coronoidectomy, followed by reconstruction with costochondral graft with 5 years of follow-up. During this period, the reconstructed graft remodeled into a neocondyle and also regrowth of the coronoid process. The mouth opening and facial symmetry were acceptable.

Ultrasound evaluation of cervical lymphadenopathy: Can it reduce the need of histopathology/cytopathology?

BACKGROUND: The differentiation between the causes of cervical lymphadenopathy is of paramount importance as these have different modalities of treatment with varying prognosis. The aim of this study was to evaluate the efficacy of B Mode and colour Doppler ultrasound (CDUS) to differentiate between benign and metastatic lymph nodes. METHODS: 100 patients of clinically palpable lymph nodes were evaluated with B Mode and CDUS. B Mode assessment included short-long (S:L) axis ratio, hilum, nodal border, echogenicity, intranodal necrosis and ancillary features. CDUS assessment included distribution of vascularity, resistive index (RI) and pulsatility index (PI). Statistical analysis was carried out with histopathological or cytological diagnosis as gold standard. RESULTS: B-Mode US correctly diagnosed 22/25 (88%) of the reactive lymph nodes giving it a sensitivity of 88% and specificity of 97.3%. Colour Doppler US diagnosed 23/25 (92%) reactive lymph nodes with a sensitivity of 92% and specificity of 97.3%. B-Mode underdiagnosed one case each of granulomatous disease and metastasis as reactive node while CDUS missed out two cases of granulomatous disease as reactive lymph node. CONCLUSION: Individual parameters of B Mode when used alone were not found to be very effective in differentiating benign and malignant lymph nodes. However features of B-Mode combined together as well as color Doppler ultrasound, help in the detection of reactive lymph nodes and can be used as a diagnostic tool with good accuracy. However, they cannot be used as a diagnostic method for metastatic or tubercular nodes and cytopathology/histopathology remains the gold standard in such situations.

Improvising livestock service in hilly regions through indigenous wisdom towards control of tick infestation: Institutional relationships.

AIM: This study was conducted to demonstrate the acaricide efficacy of novel indigenous veterinary medication shared by an outstanding knowledge holder against naturally infested cattle and efforts in mainstreaming such wisdom. MATERIALS AND METHODS: An indigenous herbal medication in control of tick infestation was documented, and experimentation was held against naturally affected cattle. Eighteen clinically infested cattle population comprising 16 crossbred and 2 non-descript cattle were purposively selected. Majority of them were adult females, reported with a higher incidence of tick at Veterinary institution. The average pre-treatment tick count at 24 sites of observations among these animals was 18.91±2.04 (Mean [x̄]±standard error [SE]). The medication was topically applied once daily for 2 days and post-treatment observations were recorded for an experimental period of 14 days' duration. RESULTS: During 24-h post-treatment observation, the medication had shown 92.95% acaricidal property with clinically irrelevant rate of tick infestation of 1.33±0.39 (x̄ ±SE) was noticed before application of subsequent (second) dosage. This practice was found significantly effective at 5% level of significance (t0.05, 23=9.08) illustrating faster relief to livestock. Animals were treated with herbal medication as per dosage on the second day and no reinfestation was noticed up to 14 days of experimental observation. CONCLUSION: The study strengthens the belief that indigenous herbal acaricide can facilitate quality livestock service at geographically distant locations. These medications can provide quicker relief, minimize tick resistance and are favorable to the environment.

Tubercular spondylitis: A review of MRI findings in 80 cases.

BACKGROUND: Tuberculosis of spine is known as tubercular spondylitis or Pott's spine. The vertebral involvement leads to various pathological processes such as abscess formation, cord compression, and gibbus deformity. Magnetic Resonance Imaging (MRI) is the imaging modality of choice which not only helps in diagnosing a case of Pott's spine but also gives valuable information about its impending complications, thereby, aiding in management of these cases. METHODS: In this study, MRI scans of 80 proven cases of tubercular spondylitis were studied retrospectively for the various pathological processes affecting the spine. RESULTS: Of the 80 cases included in this study, 68.8% of cases were male and 31.2% of cases were females. Majority of cases were seen in 21-40 yrs age group. Lumbar vertebrae were more commonly affected than the dorsal vertebrae. Contiguous two vertebral involvement was the most common pattern, and skip lesions were seen in 5% of cases. Pre-, paravertebral and epidural soft tissue component was seen in 96.25% and 62.5% of cases, respectively. Intervertebral disc Involvement was noted in 95% of cases, and cord edema was seen in 15% of cases. CONCLUSION: Tubercular spondylitis or Pott's spine is an extrapulmonary form of tuberculosis which affects the spine. MRI is the imaging modality of choice not only in diagnosing the condition but also in guiding the surgical management. The cases of spinal tuberculosis were systematically analyzed for various pathological lesions which are produced in the spine as the disease progresses.

Intracranial hypotension: An uncommon entity with common presentation.

Headache disorders are among the most common presenting complaints in any neurology outpatient department. International Headache Society classifies headaches as "primary" or "secondary". The causes of secondary headaches are varied and intracranial hypotension is one of them. It typically presents clinically with postural headaches but most of the times, its diagnosis is delayed, as it is an uncommon cause and there is poor awareness among the medical fraternity about this condition. Imaging, especially magnetic resonance imaging (MRI), plays a crucial role in the diagnosis of intracranial hypotension by not only confirming the diagnosis but also detecting the cause in some cases. This case series tries to highlight the MRI findings of intracranial hypotension in three cases with different etiologies.

Impact of portal vein infiltration and type of venous reconstruction in surgery for borderline resectable pancreatic cancer.

BACKGROUND: The International Study Group of Pancreatic Surgery (ISGPS) recommends operative exploration and resection of pancreatic cancers in the presence of reconstructable mesentericoportal axis involvement. However, there is no consensus on the ideal method of vascular reconstruction. The effect of depth of tumour invasion of the vessel wall on outcome is also unknown. METHODS: This was a retrospective cohort study of pancreaticoduodenectomy with vein resection for T3 adenocarcinoma of the head of the pancreas across nine centres. Outcome measures were overall survival based on the impact of the depth of tumour infiltration of the vessel wall, and morbidity, in-hospital mortality and overall survival between types of venous reconstruction: primary closure, end-to-end anastomosis and interposition graft. RESULTS: A total of 229 patients underwent portal vein resection; 129 (56·3 per cent) underwent primary closure, 64 (27·9 per cent) had an end-to-end anastomosis and 36 (15·7 per cent) an interposition graft. There was no difference in overall morbidity (26 (20·2 per cent), 14 (22 per cent) and 9 (25 per cent) respectively; P = 0·817) or in-hospital mortality (6 (4·7 per cent), 2 (3 per cent) and 2 (6 per cent); P = 0·826) between the three groups. One hundred and six patients (47·5 per cent) had histological evidence of vein involvement; 59 (26·5 per cent) had superficial invasion (tunica adventitia) and 47 (21·1 per cent) had deep invasion (tunica media or intima). Median survival was 18·8 months for patients who had primary closure, 27·6 months for those with an end-to-end anastomosis and 13·0 months among patients with an interposition graft. There was no significant difference in median survival between patients with superficial, deep or no histological vein involvement (20·8, 21·3 and 13·3 months respectively; P = 0·111). Venous tumour infiltration was not associated with decreased overall survival on multivariable analysis. CONCLUSION: In this study, there was no difference in morbidity between the three modes of venous reconstruction, and overall survival was similar regardless of tumour infiltration of the vein.

Doppler indices of the umbilical and fetal middle cerebral artery at 18-40 weeks of normal gestation: A pilot study.

BACKGROUND: Doppler indices form an integral component of noninvasive evaluation of fetal well-being. There is paucity of information about normal obstetric Doppler indices, particularly from the Indian subcontinent. The aim of the study was to find the values of pulsatility index (PI), resistive index (RI) of umbilical artery (UA), and fetal middle cerebral artery (MCA) and calculate cerebro-placental ratio (CP ratio) for 18-40 weeks of normal gestation so that a reference range of these Doppler values can be postulated. METHODS: 200 patients were enrolled in the study for color Doppler study of UA and MCA and were serially followed up at 4-6 weeks interval for Doppler indices. Angle-independent Doppler indices like PI and RI for MCA and UA were obtained during each examination. CP ratio was calculated in each case. All the cases were followed up till delivery and the perinatal outcome was recorded. RESULTS & CONCLUSION: The fetal MCA PI and RI showed a parabolic curve with plateau at 28-30 weeks of gestation. A significant correlation was noted between MCA PI and RI with gestational age. UA PI and RI showed a gradual fall over the gestational age with a strong negative correlation. There was a significant correlation between MCA PI and UA PI with their respective RI values. CP ratio has also shown a parabolic curve with turning point at 31-32 weeks of gestation. A significant correlation was noted between CP ratio and gestational age. CP ratio also showed a minimal positive correlation with MCA PI and a strong negative correlation with UA PI.