Array of plasmonic Vivaldi antennas coupled to silicon waveguides for wireless networks through on-chip optical technology - WiNOT.

Optical technology applied to on-chip wireless communication is particularly promising to overcome the performance limitations of the state-of-the-art networks on-chip. A key enabling component for such applications is the plasmonic antenna coupled to conventional silicon waveguides, which can guarantee full compatibility with standard optical circuitry. In this paper, we propose an antenna array configuration based on tilted plasmonic Vivaldi antennas coupled to a silicon waveguide. The details of the single antenna and of the array design are reported. The radiation characteristics of the array are suitable for on-chip point-to-point communication, i.e. in-plane maximum gain of 14.70 dB for an array with five antennas. The array exploits a travelling wave feeding scheme and, therefore, is compact in size (about 3.5 µm × 8.7 µm ).

Treating necrotizing fasciitis with or without hyperbaric oxygen therapy.

There is not enough clinical data to support the benefit of adjuvant HBO2 therapy for necrotizing fasciitis (NF). We retrospectively reviewed our 67 NF cases to compare the outcomes of adjuvant HBO2 therapy versus non-HBO2 therapy. The overall outcome and morbidity criteria were compared between a group of 29 NF patients who received the adjuvant HBO2 and a group of the remaining 38 NF patients treated by only surgery and other standards of care. This study did not find any difference between the groups in average length of hospital stay, and their mortality. However, six (25%) of the non-HBO2 group patients required amputation of extremities compared to one of the HBO2 group (Fisher exact p = 0.09). Although the benefit of adjuvant HBO2 therapy remains controversial for NF, and the outcomes of this study are not statistically significant, there is a trend in clinical outcomes which shows that the therapy has the potential to reduce the number of amputation and salvage extremities. These findings necessitate multicenter, prospective, case control study to assess the possible benefit of adjuvant HBO2 therapy for NF.

Occurrence of Campylobacter spp. in Selected Small Scale Commercial Broiler Farms of Bangladesh Related to Good Farm Practices.

Poultry origin Campylobacter is considered as one of the leading causal agents of human foodborne illness. This study was conducted to estimate the occurrence, molecular identification, and antimicrobial resistance (AMR) of Campylobacter species from the broiler farms in Bangladesh. Samples (352) were collected from 32 farms and comprised of 128 cloacal swab, 64 feed, 64 drinking water, 64 attendants' hand rinsed water, and 32 whole carcasses. All samples were tested for the presence of Campylobacter via cultural, biochemical, and PCR. The AMR was determined via the disc diffusion method. An overall occurrence of Campylobacter spp. was estimated as 26.4%. The level of Campylobacter contamination was found to be higher in conventional farms (36.4%) than the good practice farms (16.5%) including all sample categories (p = 0.000). Of 93 isolates, 67.74% and 32.26% were confirmed as C. jejuni and C. coli respectively, of which 34.92% C. jejuni, and 30% C. coli were shown to be multidrug-resistant. A significant occurrence of Campylobacter contamination in broiler farms with multidrug resistant patterns might be cogitated as serious food safety and public health concern linking to poultry food chain. A risk reduction approach through good farming practices targeting the prudent use of antimicrobials for broiler production is thus necessitated.

Identification and characterization of Salmonella spp. from samples of broiler farms in selected districts of Bangladesh.

BACKGROUND AND AIM: Salmonella spp. are an important group of pathogens responsible for human and animal diseases. This study aimed to estimate the prevalence and identify and characterize of Salmonella spp. isolated from broiler farms of Gazipur, Tangail, and Dhaka districts of Bangladesh. This study also evaluated the difference of Salmonella positivity status between two groups of farms, good practices adapted in broiler rearing at the project intervened farms, and non-project intervened traditional farms. MATERIALS AND METHODS: A total of 352 samples including 128 cloacal swabs, 32 whole carcasses, 64 feed, 64 water, and 64 attendants' hand rinses were collected through convenient sampling technique from 16 poultry food safety project of Food and Agricultural Organization of United Nations Bangladesh intervened farms and other 16 non-project intervened farms in the same location. Various cultural based techniques and biochemical methods were employed for the estimation of prevalence, isolation, and identification of Salmonella spp. which was further evaluated by polymerase chain reaction. Antimicrobial susceptibility test using disk diffusion methods and serogrouping by slide agglutination test was accomplished for additional characterization. RESULTS: Among the samples, an overall prevalence of Salmonella spp. was 31.25% (110/352) (95% confidence interval [CI]=26.44-36.38%). However, the prevalence of Salmonella spp. was 24.43% (43/176) (95% CI=18.28-31.47) in project intervened farms and 38.07% (67/176) (95% CI=30.87-45.68%) in non-intervened farms. Among the 110 isolates, 31.82% (35/110) were fitted under serogroup B, and the rest of the isolates 75 (68.18%) under serogroup D. Of 110 isolates, 82.72%, 77.27%, 81.82%, and 79.09% were susceptible to ciprofloxacin, gentamycin, norfloxacin, and streptomycin, respectively. In addition, 81.82% and 80% isolates were resistant to erythromycin and tetracycline, respectively. Isolated Salmonella spp. presented moderate resistance to both amoxicillin and azithromycin. Alarmingly, 80.91% (89/110) isolates were shown to be multidrug-resistant Salmonella spp. CONCLUSION: The study has presented a significant variation of the prevalence of Salmonella spp. between project intervened and non-project intervened farms, and this indicates project intervened farms are comparatively safer than the non-intervened farms considering public health and food safety grounds. This research outcome also has highlighted a substantial proportion of poultry origin multidrug resistance Salmonella spp. is a potential source of public health hazards. In this regard, proper awareness creation and motivational activities on good agriculture practices in poultry rearing and maintaining good personal hygiene at the farmers' level are warranted through participatory training.

Experience in managing severe malnutrition in a government tertiary treatment facility in Bangladesh.

Children with severe acute malnutrition, defined as weight-for-height <70% of the reference median or bilateral pedal oedema or mid-arm circumference <110 mm having complications, were managed in the Nutrition Unit of the Chittagong Medical College Hospital (CMCH) following the guidelines of the World Health Organization, with support from Concern Worldwide Bangladesh and ICDDR,B. In total, 171 children aged less than five years (mean +/- SD age 23.5 +/- 15.3 months) were admitted during June 2005-May 2006. Of them, 66% were aged less than two years, and 84.2% belonged to households with a monthly income of less than US$ 40. The main reason for bringing children by their families to the hospital was associated major illnesses: bronchopneumonia (33%), oedema (24%), diarrhoea (11%), pulmonary tuberculosis (9%), or other conditions, such as meningitis, septicaemia, and infections of the skin, eye, or ear. The exit criteria from the Nutrition Unit were: (a) for children admitted without oedema, an absolute weight gain of > or = 500 and > or = 700 g for children aged less than two years and 2-5 years respectively; and for children admitted with oedema, complete loss of oedema and weight-for-height >70% of the reference median, and (b) the mother or caretaker has received specific training on appropriate feeding and was motivated to follow the advice given. Of all the admitted children, 7.6% of parents insisted for discharging their children early due to other urgent commitments while 11.7% simply left with their children against medical advice. Of the 138 remaining children, 88% successfully graduated from the Nutrition Unit with a mean weight gain of 10.6 g/kg per day (non-oedematous children) and loss of -1.9 g/kg per day (oedematous children), 86% graduated in less than three weeks, and the case-fatality rate was 10.8%. The Nutrition Unit of CMCH also functions as a training centre, and 197 health functionaries (82 medical students, 103 medical interns, and 12 nurses) received hands-on training on management of severe malnutrition. The average cost of overall treatment was US$ 14.6 per child or approximately US$ 1 per child-day (excluding staff-cost). Food and medicines accounted for 42% and 58% of the total cost respectively. This study demonstrated the potential of addressing severe acute malnutrition (with complications) effectively with minimum incremental expenditure in Bangladesh. This public-private approach should be used for treating severe acute malnutrition in all healthcare facilities and the treatment protocol included in the medical and nursing curricula.

Precise detection of circular dichroism in a cluster of nano-helices by photoacoustic measurements.

Compact samples of nano-helices built by means of a focused ion beam technology with large bandwidth and high dichroism for circular polarization are promising for the construction of built-in-chip sensors, where the ideal transducer must be sufficiently confined without compromising its filtering ability. Direct all-optical measurements revealed the sample's dichroic character with insufficient details because of scattering and diffraction interference. On the other hand, photoacoustic measurements resulted to be a possible alternative investigation, since they directly deal with absorbed power and allow to get clear evidences of the differential selection for the two opposite polarization states. Multi-level numerical simulations confirmed the experimental results, proving once again the reliability of photoacoustic technique and the versatility of this class of dichroic artificial materials.

Piper betle extracts exhibit antitumor activity by augmenting antioxidant potential.

The present study was conducted to evaluate the methanolic extract of Piper betle leaves (MPBL) and its organic fractions with regard to antitumor activity against Ehrlich ascites carcinoma (EAC) in Swiss albino mice and to confirm their antioxidant activities. At 24 h post-intraperitoneal inoculation of tumor cells into mice, extracts were administered at 25, 50 and 100 mg/kg body weight for nine consecutive days. The antitumor effects of the extracts were then assessed according to tumor volume, packed cell count, viable and non-viable tumor cell count, median survival time and increase in life span of EAC-bearing mice. Next, hematological profiles and serum biochemical parameters were calculated, and antioxidant properties were assessed by estimating lipid peroxidation, reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) levels. MPBL and the ethylacetate fraction (EPBL) at a dose of 100 mg/kg induced a significant decrease in tumor volume, packed cell volume and viable cell count and increased the life span of the EAC-bearing mice (P<0.05). Hematological and serum biochemical profiles were restored to normal levels in the extract-treated mice compared with the EAC control mice. MPBL and EPBL treatment significantly decreased lipid peroxidation (P<0.05) and restored GSH, SOD and CAT levels towards normal compared with the EAC control. Taken together, the results of the present study demonstrated that Piper betle extracts exhibit significant antitumor activity, which may be attributed to the augmentation of endogenous antioxidant potential.

Coverage of emergency obstetric care and availability of services in public and private health facilities in Bangladesh.

OBJECTIVE: To assess the coverage of emergency obstetric care (EmOC) and the availability of obstetric services in Bangladesh. METHODS: In a national health facility assessment performed between November 2007 and July 2008, all public EmOC facilities and private facilities providing obstetric services in the 64 districts of Bangladesh were mapped. The performance of EmOC services in these facilities during the preceding month was investigated using a semi-structured questionnaire completed through interviews of managers and service providers, and record review. RESULTS: In total, 8.6 (2.1 public and 6.5 private) facilities per 500000 population offered obstetric care services. Population coverage by obstetric care facilities varied by region. Among 281 public facilities designated for comprehensive EmOC, cesarean delivery was available in only 215 (76.5%) and blood transfusion services in 198 (70.5%). In the private sector (for profit and not for profit), these services were available in more than 80% of facilities. In all facility types, performance of assisted vaginal delivery (range 12.2%-48.4%) and use of parenteral anticonvulsants to treat pre-eclampsia/eclampsia (range 48.6%-80.8%) were low. The main reason for non-availability of EmOC services was a lack of specialist/trained providers. CONCLUSION: Bangladesh needs to increase the availability of EmOC services through innovative public-private partnerships. In the public sector, additional trained manpower supported by an incentivized package should be deployed.

Preliminary pharmacological activity of the methanolic extract of Premna integrifolia barks in rats.

OBJECTIVE: Premna integrifolia Linn (Family: Verbenaceae) synonym of Premna serratifolia has tremendous medicinal value. Preliminary pharmacological studies were performed on the methanolic extract of Premna integrifolia (MEPI) bark to investigate neuropharmacological, analgesic, and anti-inflammatory activities. MATERIALS AND METHODS: Neuropharmacology study was done by open field and hole cross test whereas acetic acid writhing test and formalin induced pain was done for analgesic activity of MEPI. Carrageenan induced inflammatory model was considered for anti-inflammatory activity evaluation. RESULTS: A statistically significant (p0.05) decrease in locomotor activity was observed at all doses in the open-field and hole-cross tests. The extract significantly (p0.05) and dose dependently reduced the writhing reflex in the acetic acid-induced writhing test as well as licking response in the formalin induced inflammatory pain. At 200 mg/kg body weight dose, MEPI showed 71.16% inhibition in carrageenan induced anti-inflammatory activity. CONCLUSION: The finding of this study suggests that MEPI will provide scientific support for the use of this species in traditional medicine.

Thromboembolic complications in burn patients and associated risk factors.

Early mobilization and deep venous thrombosis (DVT) prophylaxis have been shown to reduce the incidence of DVT and pulmonary embolism among hospitalized patients, yet thromboembolic complications remain a great concern, especially to those who remain immobilized for an extended period of time. There are many risk factors associated with the development of thromboembolism, especially DVT. The main objective of this retrospective study is to estimate the occurrence of DVT in burn patients and to investigate some burn-related risk factors. A retrospective examination of DVT cases was conducted among the acute burn patients admitted to our Regional Burn Center during 2008. The analysis included the demographic factors, preexisting medical conditions, ventilator support, number of surgeries and blood transfusions, and use of central line. There was a total of 97 diagnosed patients with DVT and among them 86 were adult acute burn patients. There were 113 diagnosed with DVTs in 86 burn patients, including 22 patients diagnosed with DVT at multiple sites either in one screening or in subsequent screenings. Incidence of DVT at the center was 5.92 per 100 adult acute burn admissions. Men had more DVT than women (6.87 vs. 3.34%, relative risk 2.05, P < .05). The average percentage of %TBSA was smaller in the patients who were more than 50 years of age compared with the patients who were 49 years or younger (21.97 vs. 34.77%, P < .05). Among the patients with DVT, 80 (93%) had a central venous catheter before DVT developed and the other six never had a central venous catheter. The most common site for DVT development was common femoral vein site 89%. The average number of procedures before DVT was 7.84 ± 8.36, and blood transfusions were 39.55 ± 108.37 units. Six patients (7%) died in the hospital within these study cohorts and there was no indication that pulmonary embolism was the cause of the deaths. The study showed that the incidence of DVT in the burn center was comparable with the incidences reported in the literature. Being of male sex, a smoker, an alcoholic, high-age group, high %TBSA, use of central line, increased number of surgeries, and increased number of blood transfusions are identified as possible predisposing factors for DVTs. Further meaningful evaluation to determine the incidence of DVT in burn patients and its associated risk factors will require large multicenter, well-controlled, prospective designed study.

Antioxidant, analgesic and anti-inflammatory activities of the methanolic extract of Piper betle leaves.

OBJECTIVE: The present study was designed to evaluate the antioxidant, analgesic, and anti-inflammatory activities of the methanolic extract of Piper betle leaves (MPBL). MATERIALS AND METHODS: MPBL was evaluated for anti-inflammatory activity using carrageenan-induced hind paw edema model. Analgesic activity of MPBL was evaluated by hot plate, writhing, and formalin tests. Total phenolic and flavonoids content, total antioxidant activity, scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, peroxynitrate (ONOO) as well as inhibition of total ROS generation, and assessment of reducing power were used to evaluate antioxidant potential of MPBL. RESULTS: The extract of MPBL, at the dose of 100 and 200 mg/kg, produced a significant (p<0.05) increase in pain threshold in hot plate method whereas significantly (p<0.05) reduced the writhing caused by acetic acid and the number of licks induced by formalin in a dose-dependent manner. The same ranges of doses of MPBL caused significant (p<0.05) inhibition of carrageenan-induced paw edema after 4 h in a dose-dependent manner. In DPPH, ONOO(-), and total ROS scavenging method, MPBL showed good antioxidant potentiality with the IC50 value of 16.33±1.02, 25.16±0.61 , and 41.72±0.48 µg/ml, respectively with a significant (p<0.05) good reducing power. CONCLUSION: The findings of the study suggested that MPBL has strong analgesic, anti-inflammatory, and antioxidant effects, conforming the traditional use of this plant for inflammatory pain alleviation to its antioxidant potentiality.

Timing of enteral feeding in cerebral malaria in resource-poor settings: a randomized trial.

BACKGROUND: Early start of enteral feeding is an established treatment strategy in intubated patients in intensive care since it reduces invasive bacterial infections and length of hospital stay. There is equipoise whether early enteral feeding is also beneficial in non-intubated patients with cerebral malaria in resource poor settings. We hypothesized that the risk of aspiration pneumonia might outweigh the potential benefits of earlier recovery and prevention of hypoglycaemia. METHOD AND FINDINGS: A randomized trial of early (day of admission) versus late (after 60 hours in adults or 36 hours in children) start of enteral feeding was undertaken in patients with cerebral malaria in Chittagong, Bangladesh from May 2008 to August 2009. The primary outcome measures were incidence of aspiration pneumonia, hypoglycaemia and coma recovery time. The trial was terminated after inclusion of 56 patients because of a high incidence of aspiration pneumonia in the early feeding group (9/27 (33%)), compared to the late feeding group (0/29 (0%)), p = 0.001). One patient in the late feeding group, and none in the early group, had hypoglycaemia during admission. There was no significant difference in overall mortality (9/27 (33%) vs 6/29 (21%), p = 0.370), but mortality was 5/9 (56%) in patients with aspiration pneumonia. CONCLUSIONS: In conclusion, early start of enteral feeding is detrimental in non-intubated patients with cerebral malaria in many resource-poor settings. Evidence gathered in resource rich settings is not necessarily transferable to resource-poor settings. TRIAL REGISTRATION: Controlled-Trials.com ISRCTN57488577.

Purpura fulminans: a case series managed at a regional burn center.

Purpura fulminans (PF) is a protein C deficiency disease process with a high case fatality rate; however, overall incidence of the disease remains relatively very low. The similarity between skin necrosis secondary to PF and full-thickness skin burns provides the rationale for treating PF case in a burn center. In this case series we reviewed our experiences in managing PF and their associated favorable outcomes. Retrospective chart review of five PF cases managed between September 2004 and August 2006 at our Burn Center with 100% survival. Management of cases following the standard care of the Burn Center for a full-thickness burn included antibiotics, fluid resuscitation, surgical debridement with skin grafting, and activated protein C (Drotrecogin alfa) replacement. Two patients required amputations of extremities and all had surgical debridement. One required hemodialysis and two needed both hemodialysis and positive-pressure mechanical ventilator. No patient experienced any bleeding complications during or after surgery while receiving activated protein C. Early diagnosis and treatment at a burn center may reduce mortality and morbidity and loss of extremities in PF cases.