Search PubMed⌕ Search

Biomedical subjects

M Patel

Publications and source records attributed to M Patel.

At least 253 records · Page 14Linked to original sources

Importance of fungus colonization in failure of silicone rubber percutaneous gastrostomy tubes (PEGs).

Silicone rubber PEG tubes or replacements were recovered from 111 patients and examined for blockage, dilatations, tears, breaks, or loss of elasticity. All irregularities were stained and examined for fungus using lactophenol cotton blue stain. The intraabdominal portion of the PEG failed from obstructions, loss of elasticity, or tears related to fungus colonies in 36% of cases. An additional 34% were colonized with fungi but did not fail. On frozen section, the fungus invaded the wall of the tubing. The extraabdominal PEG tubing failed from fungi in 12, and 10 additional tubes had colonizations. Nine tubes had distal clogging with crystalline material that is believed to arise from medication. Fungus tube failure occurred in 37% of the tubes in place 250 days and in 70% of tubes in place 450 days. Fungus is an important cause of PEG failure; recommendations are provided to maintain tube patency.

Endoscopy↗

Clear plastic cups: a childhood choking hazard.

The disposable plastic beverage cup is not usually regarded as hazardous to young children. Certain varieties of these products however, are manufactured from a brittle, clear plastic that easily cracks and fragments. While most conscientious parents keep their children safe from peanuts, balloons, and other known choking hazards, a child can surreptitiously bite a cup edge and aspirate the fragment. We report two cases of foreign body aspiration involving clear plastic cups that went undetected one of which remained 21 months following a negative rigid bronchoscopy. Diagnostic difficulties are related to the transparency and radiolucency of these objects. When suspicious of foreign body aspiration in children, otolaryngologists should inquire about the availability of clear plastic cups in the household and be mindful of the diagnostic pitfalls. Further investigations including CT scanning and repeat bronchoscopy may be helpful in cases of suspected missed foreign bodies. An educational campaign aimed at prevention and placement of product package warning labels should be established.

Airway Obstruction↗

Reversibility of cerebral ventricular enlargement in anorexia nervosa, demonstrated by quantitative magnetic resonance imaging.

OBJECTIVE: To determine the reversibility of the loss of brain parenchyma and ventricular enlargement in patients with anorexia nervosa after refeeding. STUDY DESIGN: Quantitative magnetic resonance imaging was performed on three groups of subjects: (1) 12 female adolescents hospitalized with anorexia nervosa, (2) the same 12 patients after nutritional rehabilitation, a mean of 11.1 months later, and (3) 12 healthy age-matched control subjects. Sixty-four contiguous coronal magnetic resonance images, 3.1 mm thick, were obtained. With a computerized morphometry system, lateral and third ventricular volumes were measured by a single observer unaware of the status of the patient. RESULTS: On admission, patients were malnourished and had lost an average of 11.7 kg (body mass index, 14.3 +/- 2.0 kg/m2). After refeeding, they gained an average of 9.7 kg (body mass index, 17.9 +/- 1.5 kg/m2). Total ventricular volume decreased from 17.1 +/- 5.5 cm3 on admission to 12.4 +/- 3.0 cm3 after refeeding (p < 0.01) and returned to the normal range. The degree of enlargement of the third ventricle was greater than that of the lateral ventricles. There was a significant inverse relationship between body mass index and total ventricular volume (r = -0.63; p < 0.05). CONCLUSION: In patients with anorexia nervosa, cerebral ventricular enlargement correlates with the degree of malnutrition and is reversible with weight gain during long-term follow-up.

Adolescent↗

Requirement for superoxide in excitotoxic cell death.

We tested the pathogenic role of O2-) radicals in excitotoxic injury. Inactivation of the TCA cycle enzyme, aconitase, was used as a marker of intracellular O2- levels, and a porphyrin SOD mimetic was used to scavenge O2-. The selective, reversible, and SOD-sensitive inactivation of aconitase by known O2- generators was used to validate aconitase activity as a marker of O2- generation. Treatment of rat cortical cultures with NMDA, KA, or the intracellular O2- generator PQ2+ produced a selective and reversible inactivation of aconitase, which closely correlated with subsequent cell death produced by these agents. The SOD mimetic, but not its less active congener, attenuated both aconitase inactivation and cell death produced by NMDA, KA, and PQ2+. These results provide direct evidence implicating O2(-) generation in the pathway to excitotoxic injury.

Aconitate Hydratase↗

A comparison between epidural anaesthesia using alkalinized solution and spinal (combined spinal/epidural) anaesthesia for elective caesarean section.

In a double-blind investigation, 40 women undergoing elective lower segment caesarean section were randomly divided into two groups. Group I (n = 20) received spinal anaesthesia with 2.0 ml hyperbaric 0.5% bupivacaine using a single space combined spinal epidural technique. Group II (n = 20) received epidural anaesthesia with a local anaesthetic mixture consisting of 0.5% bupivacaine plain 10 ml and 2% lignocaine plain 10 ml to which was added 0.1 ml of adrenaline 1 in 1000 and 2 ml of 8.4% sodium bicarbonate. The mean onset times of sensory block to T4 and grade 3 motor blockade were 7.9 min and 9.5 min respectively in the spinal group, compared to 13.1 min and 16.3 min in the epidural group. These differences were both significant (P < 0.05). There was no difference between the two groups in the quality of analgesia or the incidence of hypotension and nausea. The relatively rapid onset of the pH adjusted epidural solution may provide an attractive alternative to spinal anaesthesia. Moreover, this study underlines the important role of pH adjusted epidural solutions in parturients progressing to emergency caesarean section with epidural catheters previously inserted for labour analgesia.

Clinical Trial↗

Demographic and clinical characteristics of patients with episodic migraine versus chronic daily headache.

We compared data from 243 patients with episodic migraine (EM) and 132 patients with chronic daily headache (CDH). We divided the latter group into those with tension-type headache only (CDH Type 1) and those with headaches having migrainous features (CDH Types 2 + 3) and compared each with the EM group and all three groups with one another. CDH Type 1 patients differed from those in the other groups by virtue of gender (more often male) and mean age at headache onset (older). The CDH Types 2 + 3 and EM groups differed only in that the former were more likely to have undergone a brain-imaging study. These data suggest that CDH Type 1 may represent a distinct headache syndrome, while CDH Types 2 + 3 closely resemble episodic migraine.

Adult↗

The high morbidity associated with a measles outbreak in a west Australian town.

OBJECTIVE: To determine the effectiveness of the measles vaccine and to record the morbidity during a measles outbreak. METHODOLOGY: A retrospective cohort study was carried out. It was a community-based study in Bunbury, Western Australia, between February and May 1994, of 53 cases of measles and their household contacts. RESULTS: Of the 53 cases of measles, 24 were from one high school. Only two cases occurred in the high school class that had received the National Health and Medical Research Council of Australia recommended measles, mumps and rubella (MMR) booster 12 months earlier. Neither had been vaccinated. Vaccine effectiveness was 91% (95% confidence interval 67-97%). Ten cases had complications of measles and a further five were admitted to hospital. Doctors prescribed antibiotics to 29 cases and metoclopramide to five cases. One month elapsed between the day the index case became ill and the first notification to the community health centre. CONCLUSIONS: The low herd immunity that led to this high school outbreak can be attributed to low vaccine coverage. There was a significant morbidity associated with this outbreak that may have been averted if earlier notification had occurred. The MMR booster dose should be offered to all 10-16 year olds to prevent high school outbreaks.

Adolescent↗

Laparoscopic cholecystectomy and previous abdominal surgery: a safe technique.

Previous abdominal surgery has been cited as a contraindication to the performance of laparoscopic cholecystectomy. The present paper describes a technique whereby a Hasson cannula was introduced into the right iliac fossa by the open technique, using a method similar to an appendicectomy. The laparoscope was then introduced through this port and the safe introduction of other ports was achieved. Any adhesions were divided at this stage. The laparoscope was then moved to the umbilical port and a conventional laparoscopic cholecystectomy performed. In the series of six patients with upper or upper and lower abdominal scars, no patient suffered a complication or required a conversion to laparotomy. However, the operating time was increased from 75 to 105 min. This method involves open introduction of the primary trocar in an area devoid of adhesions. It was shown to be safe and with this method previous abdominal surgery should not be regarded as a contraindication.

Adult↗

Human neutrophil functions are inhibited in vitro by clinically relevant ethanol concentrations.

Neutrophils [polymorphonuclear neutrophils (PMNs)] play a pivotal role in host defense in man. These defenses may be compromised, however, in alcohol users and abusers. We therefore evaluated the effect of ethanol levels (12.5 to 500 mg/dl), on key functions of human PMNs-chemotaxis and production of reactive oxygen species-and on changes in cytosolic-free calcium ([Ca2+]i), a pivotal intracellular mechanism of PMN activation. Ethanol significantly inhibited chemotaxis as evaluated by formyl-methionyl-leucyl-phenylalanine (fMLP)-induced upregulation of surface adhesion molecules (CD11b). fMLP-induced PMN elongation was only inhibited by a very high ethanol concentration of 500 mg/dl. Production of reactive oxygen species by normal PMNs was assessed by either chemiluminescence (CL) for hypochlorous acid or ferricytochrome c reduction (FCR) for superoxide anions. For PMN stimulated by fMLP, ethanol inhibited CL but not FCR. For PMNs activated by phorbol myristate acetate, ethanol inhibited both CL and FCR. Ethanol did not alter baseline [Ca2+]i, as assessed by videomicroscopy using the Ca(2+)-sensing fluorescent dye Fura-2-AM, but did significantly potentiate the increase in peak [Ca2+]i levels that occurs in response to stimulation by fMLP. Calcium channel blockers attenuated ethanol's inhibition of CL. Thus, acute in vitro ethanol, at clinically relevant concentrations, can inhibit several critical aspects of PMN functions. But, in PMNs, unlike neural cells, these inhibitory effects do not seem to be mediated by decreases in Ca2+ influx or in [Ca2+]i.

Calcium↗

Subdural empyema in 12-year-old girl: the value of magnetic resonance imaging.

A 12-year-old girl presented with an acute history of fever, headaches, and focal neurological deficits. An initial computed tomography (CT) scan of the head was nondiagnostic whereas plain and gadolinium-enhanced magnetic resonance imaging (MRI) detected an extensive subdural empyema. The report emphasizes the hazard of relying on a nondiagnostic CT scan in a septic patient with deteriorating neurological function, and the need of MRI with contrast enhancement if subdural empyema is a serious clinical concern.

Child↗

Cerebral CT venography.

PURPOSE: To produce cerebral venograms with thin-section helical computed tomography (CT) and to assess their diagnostic utility. MATERIALS AND METHODS: Thirty-six CT venograms were obtained in 33 patients after intravenous administration of iodinated contrast material. Eighteen patients had suspected dural sinus thrombosis. Twelve patients had tumor adjacent to a major venous structure. Three patients underwent CT venography during CT angiography. RESULTS: Superior sagittal, transverse, and straight sinuses were identified on every CT venogram. Other veins were seen with high frequency. Dural sinus thrombosis was diagnosed in seven patients, with magnetic resonance (MR) venographic correlation in five patients. CT venograms were easier to interpret and had fewer artifacts than MR venograms. Relationships of tumor to adjacent cerebral venous structures were well shown on CT venograms. CONCLUSION: CT venography yields detailed images of the intracranial venous circulation with consistently high quality. It is a rapid, useful method for diagnosis of dural sinus thrombosis and for preoperative mapping of venous structures in patients with neoplasm.

Adult↗

MRI signal hyperintensities in geriatric depression.

OBJECTIVE: The authors rated periventricular and subcortical signal hyperintensities on magnetic resonance imaging (MRI) scans in elderly patients with depression and in normal subjects with similar demographic features to examine whether such changes discriminate patients with depression from normal subjects and whether they are associated with any clinical variables. METHOD: Two established hyperintensity rating systems were used to compare the MRI brain scans of 48 elderly patients with depression diagnosed according to DSM-III-R with the scans of 39 normal elderly subjects. RESULTS: Elderly depressed patients manifested significantly more severe hyperintensity ratings in the subcortical gray matter than age-matched comparison subjects. Significant differences were not identified between patients with similar current ages and cerebrovascular disease risk who had early-onset or late-onset depression. CONCLUSIONS: These findings support those of neuroimaging studies implicating the basal ganglia in depression and geriatric depression. The data suggest that the relationship observed in some reports between late-onset depression and MRI hyperintensities is most likely a function of cerebrovascular disease risk and age.

Age Factors↗

Effects of pineal indoles and parachlorophenylalanine on seasonal reproduction in the pigeon

The effect of melatonin, methoxytryptophol (ML), methoxytryptamine (MT) and parachlorophenylalanine (p-CPA) on the mass and histology of the testes and the adrenal and thyroid glands and on serum thyroid hormone levels have been studied in the recrudescent phase of the feral pigeon Columba livia. All the pineal indoles showed a common anti-gonadal effect, resulting in the arrest of spermatogenesis and the degeneration of germ cells. Treatment with melatonin resulted in adreno-cortical enlargement and medullary hypertrophy, whereas ML, MT and p-CPA induced medullary enlargement and hypertrophy without having much influence on the cortex. Treatment with melatonin and ML brought about colloid retention in the thyroid follicles, while MT and p-CPA induced colloid depletion and hypertrophy of the follicular epithelium. From the present study, it can be concluded that both pineal indoles and p-CPA induce testicular regression in the breeding phase but do so by different mechanisms.

Journal Article↗

A clinician friendly computerised head and neck oncology audit: the first year results.

Surgical audit is only as good as the information recorded and data entry is often onerous and the domain of the enthusiastic clinician or research follow. A head and neck oncology audit which incorporates a specific software program has been established in our department. The software interface increases the user friendliness of two conventional database systems, ACCESS and SUPERBASE and structures data input for the clinical situation. The program has been designed for ease of use by every clinician irrespective of their computer competence. The departmental prospective audit has been active since January 1993 and the essential details on new patient presentation, assessment, surgery and outcome for the first year are included in this article.

Aged↗