Larvicidal and Pupicidal Activities of Alizarin Isolated from Roots of Rubia cordifolia Against Culex quinquefasciatus Say and Aedes aegypti (L.) (Diptera: Culicidae).

The mosquitocidal activities of different fractions and a compound alizarin from the methanol extract of Rubia cordifolia roots were evaluated on larvae and pupae of Culex quinquefasciatus Say and Aedes aegypti (L.) (Diptera: Culicidae). Larvae and pupae were exposed to concentrations of 2.5, 5.0, 7.5 and 10 ppm for fractions and 0.5, 1.0, 1.5 and 2.0 ppm for compound. After 24 h, the mortality was assessed and the LC50 and LC90 values were estimated for larvae and pupae. Among the 23 fractions screened, fraction 2 from the methanol extract of R. cordifolia showed good mosquitocidal activity against C. quinquefasciatus and A. aegypti. LC50 and LC90 values of fraction 2 were 3.53 and 7.26 ppm for C. quinquefasciatus and 3.86 and 8.28 ppm for A. aegypti larvae, and 3.76 and 7.50 ppm for C. quinquefasciatus and 3.92 and 8.05 ppm for A. aegypti pupae, respectively. Further, the isolated compound alizarin presented good larvicidal and pupicidal activities. LC50 and LC90 values of alizarin for larvae were 0.81 and 3.86 ppm against C. quinquefasciatus and 1.31 and 6.04 ppm for A. aegypti larvae, respectively. Similarly, the LC50 and LC90 values of alizarin for pupae were 1.97 and 4.79 ppm for C. quinquefasciatus and 2.05 and 5.59 ppm for A. aegypti pupae, respectively. The structure of the isolated compound was identified on the basis of spectroscopic analysis and compared with reported spectral data. The results indicated that alizarin could be used as a potential larvicide and pupicide.

Detecting and defining the anatomic extent of large nerve perineural spread of malignancy: comparing "targeted" MRI with the histologic findings following surgery.

BACKGROUND: The accurate preoperative identification of the extent of perineural spread (PNS) of malignancy along a cranial nerve is vital to the design of an appropriate surgical resection. Our purpose was to determine the sensitivity of targeted MRI in predicting the presence of disease and the anatomic extent of spread when compared with histologic findings. METHODS: A retrospective review was performed of 25 patients with PNS who had targeted MRI and surgery to excise perineural tumor (2002-2008). RESULTS: MRI detected PNS in 30 of 30 nerves (100%) with 1 false positive. MRI correctly identified the extent of spread based on histology in 25 of 30 nerves (83.3%). In 4 of 30 cases (13.3%) MRI underestimated the extent of spread proximal to the Gasserian ganglion that, if diagnosed preoperatively, may have deemed the patient inoperable. CONCLUSIONS: MRI demonstrated the presence and anatomic extent of PNS in the majority of cases. MRI may underestimate microscopic spread proximal to the Gasserian ganglion.

Myxoma of the masticator space.

We describe a rare case of a surgically proven myxoma arising within the masticator space probably from a pterygoid muscle. The lesion showed characteristic hyperintensity on T2-weighted images and did not enhance following gadolinium.

Ultrasound of the hepatobiliary-pancreatic system.

Ultrasound (US) remains an excellent first line investigation of the gallbladder and for indicating diagnoses and defining levels of extrahepatic biliary obstruction and screening for liver metastases. It is extremely useful in assisting interventional procedures and assessing the status of hepatic vessels. As a nonoperative procedure, endoscopic ultrasound (EUS) can accurately locate and locally stage pathology of the pancreas and periampullary region and even provide reliable biopsy evidence in experienced hands. A limitation, of course, is its field-of-view restriction, which prevents identification of distant metastatic disease. This restriction is not present with laparoscopic ultrasound (LUS), which apart from being an operative procedure, has all the other advantages of EUS and in addition can identify nodal, hepatic, and extrahepatic metastatic spread. Greater use of intraoperative biopsy should assist in identifying nodal disease but requires the readily available services of a pathologist. Local disease may be even more definable using the newer technology of intraductal ultrasound (IDUS). Intraoperative ultrasound (IOUS), whether direct or via the laparoscope, is now an indispensable tool for all surgeons who want to perform hepatobiliary-pancreatic surgery at the highest level.

Ultrasound of soft tissue masses.

The current clinical applications of ultrasonography (US) of soft tissue masses are discussed. These include the detection of occult masses, the characterization of palpable masses, tumor surveillance, and US guided percutaneous aspirations/biopsies of soft tissue masses.

The pharmacokinetics and UK usage of heparin in vascular intervention.

Intravascular heparin is used routinely during peripheral and visceral angioplasty, although usage and dose vary widely. The aims of this prospective study were to: (1) Determine the pattern of Heparin usage by Vascular/Interventional Radiologists in the UK. (2) Determine the optimum doses of Heparin for vascular intervention on the basis of its pharmacokinetic profile. A questionnaire was sent to Consultant Radiologists who were also members of the British Society of Interventional Radiology (BSIR), regarding their use of heparin during peripheral angioplasty. This included heparin doses in flushing solution, timing and amounts of heparin used as a bolus dose and monitoring of clotting times. Seventy-three percent returned completed forms. A wide variation in practice was shown. Apart from the variety of individual protocols in use, significant findings were that more than 75% of the respondents were giving heparin as a bolus only after the lesion had been crossed with a guide-wire. None of the respondents were monitoring clotting times, even in prolonged and complicated procedures. The pharmacokinetic profiles of two separate bolus doses of heparin in two groups of 30 and 25 patients each were then evaluated. Our results showed that a 3000 IU bolus of heparin maintained the plasma APTT in the therapeutic range (at least twice the normal value), for at least 30 min in the majority of patients. A 5000 IU bolus maintained the APTT in the therapeutic range for 45 min in the vast majority of patients. Apart from minor bruising at the compression site and slightly increased compression times in a small number of patients, no significant immediate complication was noted. We conclude that in the context of peripheral angioplasty, there is a wide variation in the use of heparin as an adjunct to the procedure. In the light of our own experience we recommend a 3000 IU intra-arterial bolus of unfractionated heparin to be given once arterial access has been achieved. This would cover short, uncomplicated procedures. The larger 5000 IU dose would be more appropriate for longer and more complicated procedures. We also recommend monitoring APTT values in prolonged procedures, with administration of further bolus doses of heparin if required.

Ultrasound and computed tomography appearances of primary hepatic leiomyosarcoma.

Primary hepatic leiomyosarcoma is a rare condition. The ultrasound and computed tomography findings in a 73 year old female patient are described. Previous reports have concentrated on the histopathological features and clinical presentation of the condition.

Complications of intraarterial digital subtraction angiography in patients investigated for cerebral vascular disease.

395 patients (236 males, mean age 55.6 years: 159 females, mean age 52.2 years) with suspected transient ischaemic attacks or previous strokes underwent intraarterial digital subtraction angiography (IADSA) over a 3-year period ending in March 1991. All procedures were performed via the femoral approach and the majority consisted of arch studies followed by selective catheterization. 253 (64.1%) of the patients had extracranial vascular disease confirmed at angiography. A retrospective analysis of the patients' records was made to extract all possible complications. Complications were defined as any untoward symptoms or signs occurring within 48 h and which could have been related to the angiogram. Neurological complications occurred in 15 (3.89%) patients. 10 (2.5%) patients had transient complications which resolved completely within 24 h. In three (0.8%) patients the neurological deficit was reversible, recovering fully within 6 days. Two (0.52%) patients were left with residual disability from stroke at 10 days. The permanent neurological complication rate is in the lower range of the rates recorded in previous conventional angiographic studies. We conclude that IADSA is a relatively safe and reliable form of investigation in patients with suspected cerebral vascular disease.

Phrenic and recurrent laryngeal motoneuron activities during hyperoxia and hypoxia in piglets.

We hypothesized that synchronization of inspiratory motoneurons may involve inputs from two central pattern generators (CPG): one characterized by medium-frequency (< 50 Hz) and the other by high-frequency oscillations (> or = 50 Hz). We studied phrenic and recurrent laryngeal nerve activities recorded during hyperoxia and hypoxia in Saffan anesthetized, paralyzed, and artificially ventilated piglets. Spectral analyses, derived from the full as well as partitioned halves of inspiration, showed that phrenic and recurrent laryngeal discharges contained peaks in the medium-frequency band, which were indicative of common inputs. The phrenic spectra of many animals had peaks in the high-frequency band; such peaks were uncommon in recurrent laryngeal spectra; consequently, correlated activities corresponding to high-frequency oscillations were not usually observed. Thus, it is likely that acquisition of modulating inputs from a high-frequency CPG may emerge in an age-dependent manner in different motoneuron pools. During hypoxia, both phrenic and recurrent laryngeal discharges were facilitated as shown by increases in both the amplitudes of signal-averaged histograms and the magnitudes of their respective power spectral activities. Also, there was a significant increase in the values of phrenic-recurrent laryngeal coherence estimates in the medium-frequency region. Hence, medium-frequency oscillations are more apparent in early development, perhaps to facilitate synchronization of inspiratory motoneuron activities, especially under conditions of increased chemical drive.

Cardiac responses elicited by stimulation of loci within stellate ganglia of developing swine.

Stimulation with bipolar electrodes of specific loci in stellate ganglia elicited in anesthetized piglets, 1-4 weeks of age, alterations in cardiac function and aortic pressure. Responses were also elicited by chemical stimulation in specific loci of these ganglia. The probability of eliciting a cardiovascular response by stimulating loci in a stellate ganglion increased with increasing postnatal age. For instance, no responses were elicited when loci in the left stellate ganglia of 1-week-old piglets were stimulated. Significant heart rate responses were obtained only when loci in right stellate ganglia were stimulated. The number of ganglionic loci from which cardiovascular responses were obtained increased with increasing postnatal age. It is concluded that the capacity of stellate ganglion neurons to modulate the cardiovascular system matures during the first four weeks of life, heart rate being modulated primarily by neurons in the right stellate ganglion and inotropism by neurons in both stellate ganglia.

Central patterning of inspiratory activity in the neonatal period.

We hypothesized that synchronization of neonatal inspiratory motoneurons is achieved by common inputs from one or more central pattern generators. Such inputs are manifested in neural discharges as medium-frequency (less than 50 Hz) and/or high-frequency (greater than or equal to 50 Hz) oscillations. Furthermore, if both oscillations appeared, one or both might be gated, i.e. present only in the first or second half of inspiration. The spontaneous discharges of phrenic (C5 and C6) roots and hypoglossal nerves were recorded in anesthetized or decerebrated, vagotomized, paralyzed and artificially ventilated neonatal swine. Autopower spectral analyses showed that phrenic discharges had peaks in the medium- and/or the high-frequency band. Phrenic spectra, derived from either half of inspiration, demonstrated that, while both types of oscillation were present throughout inspiration, their amplitudes were larger during the second half of inspiration. However, comparisons of the relative distributions of power in each half of inspiration showed that the increase of high-frequency power was much larger than that of medium-frequency power during the second half of inspiration. In contrast to phrenic spectra, hypoglossal spectra had peaks only at medium-frequencies; consequently, correlated frequencies (indicative of common inputs) in phrenic-hypoglossal coherence spectra were present at those frequencies. The presence of highly correlated frequencies provided strong evidence of a medium-frequency pattern generator which may remain operative beyond the neonatal period.

Respiratory modulation of sympathetic activity in neonatal swine.

Spontaneous efferent sympathetic activity (cervical sympathetic and splanchnic nerves) was recorded simultaneously with efferent phrenic discharge, with aortic pressure, and with the electrocardiogram in less than 1- to 51-day-old neonatal swine anesthetized with Saffan (alfaxalone). Power spectral analyses of sympathetic discharge revealed a frequency range of 4-36 Hz, with peaks distributed in four regions of the spectrum (4-6 Hz, 8-15 Hz, 16-22 Hz, and 28-36 Hz). Inspiratory modulation was readily apparent since sympathetic power spectral energy was greatest during the time of phrenic activity. Alterations in pulmonary afferent inputs (e.g., lung inflation tests and/or vagotomy) altered both phrenic and sympathetic activity. Use of the respiratory-cardiac modulation ratio indicated that respiratory modulation of sympathetic activity was greater than cardiac modulation. Complex afferent inputs, i.e., fictive Valsalva maneuver, indicated an immaturity of integration within the cardiovascular regulatory system. The adult patterns of blood pressure changes and heart rate responses were delayed until approximately 1 mo of age. Calculations of Valsalva ratios (ratio of maximal R-R interval to minimal R-R interval) indicated delayed onset of heart rate responses, reflecting the maturation of cardiovascular reflexes during the neonatal period.

Evidence for central patterning of sympathetic discharge in kittens.

Cervical sympathetic nerve discharges in kittens were examined using power spectral techniques to describe the frequency components of nerve activities and to obtain evidence of modulation by central rhythm generators. Peaks in sympathetic spectra appeared in the 4-11 Hz band; however, coherences between sympathetic nerves occurred at 4-5 Hz, while that between sympathetic and phrenic nerves occurred at 8-9 Hz. These findings indicate modulation by sympathetic and inspiratory rhythm generators.

Efferent phrenic nerve and respiratory neuron activities in the developing kitten: spontaneous discharges and hypoxic responses.

Efferent phrenic nerve and medullary respiratory neuron discharges were examined for age-dependent changes of activities during normocapnic hyperoxia and hypoxia in anesthetized and decerebrate kittens (22-150 days old). In animals less than 39 days of age, phrenic power spectra during hyperoxia were dominated by components in the medium-frequency band (20-50 Hz), whereas spectra of animals of at least 39 days of age were dominated by components in the high-frequency band (50-100 Hz). Such high-frequency oscillations were also observed in the power spectra of some inspiratory neurons in animals of at least 43 days old. In hypoxia, the amplitude of phrenic discharge exhibited an initial facilitation followed by a diminution (i.e. biphasic response) in animals 39 days old or younger. In animals older than 39 days, however, hypoxia elicited a sustained facilitation of phrenic discharge amplitude. In contrast, no such age-dependent change in response pattern to hypoxia was observed for neuronal discharges; rather, responses of most neurons consisted of either decreases of discharge frequency, or complete abolishment of discharges.

Effects of anesthesia on efferent phrenic activity in neonatal swine.

The effects of two levels of Saffan anesthesia (standard recording level: 2-4 mg/kg/min, and 10X recording level) and a single level of pentobarbital (5 mg/kg) on the power spectral density of efferent phrenic discharge were investigated in piglets aged from less than 1 day to 50 days. The phrenic high frequency oscillation (HFO) was present in decerebrate, unanesthetized piglets and in piglets anesthetized with Saffan, albeit reduced at 10 times recording level, but was absent under pentobarbital. The results indicate that Saffan does not have a significantly depressant effect on the phrenic HFO in developing swine.

Unusual observations on hypermagnesemic levels and cardiorespiratory effects in neonatal swine.

Mg is being used as a therapeutic agent in different clinical conditions, i.e. preeclampsia or eclampsia, and as a tocolytic agent to prevent premature delivery. For these reasons we decided to systematically investigate the cardiovascular and respiratory effects of excess Mg in 25 piglets less than 1 day to 3 months of age, lightly anesthetized with Saffan, tracheotomized, paralyzed with C-10 and artificially ventilated on 100% O2. A 1.0 M infusion of MgCl2 was given for 15-60 min, and arterial plasma samples were drawn before and at the end of the infusion for the determination of plasma Mg and Ca levels. Phrenic nerve activity was recorded monophasically simultaneously with arterial blood pressure, electrocardiogram, end-tidal CO2 and intratracheal pressure on a dynograph and on analog tape. In a subset of experiments (n = 6), spontaneous ventilation was monitored in piglets of different ages to determine the Mg concentration at which spontaneous ventilation ceased. Blood gases were measured at 45-min intervals, as well as both immediately before and after the MgCl2 infusion, and pCO2 and pH were maintained within normal limits. As a consequence of the high plasma concentration of Mg, mean arterial pressure and heart rate declined, and the inspiratory duration significantly decreased. Our results indicate that young piglets can survive high levels of plasma Mg (greater than 14 mM).