IMMOBILIZATION OF NITROGEN-FIXING BACILLUS FLEXUS STRAIN BLY01 FOR ENHANCED SYNTHESIS OF α-AMYLASE AND ALKALINE PHOSPHATASE

A nitrogen-fixing gram positive spore forming bacteria was isolated from potato waste and produced α-amylase and alkaline phosphatase (APase) when the organism had been fed on starch and insoluble Ca2(PO4)3 in nitrogen free medium. The organism was identified as Bacillus flexus BLY01 on the basis of morphological as well as phylogenetic analysis using 16S rDNA sequencing. Under optimized conditions in broth culture, fresh cells produced about 56 unit/ml of α-amylase and 16.75 unit/ml of alkaline phosphatase. The log phase cells of strain BLY01 had been immobilized in Ca-alginate gel capsules and were used for the semi-continuous production of the substrate specific enzymes individually. The immobilized cells showed about 27% and 126% enhancement in activity of α-amylase and APase, respectively. The immobilized system retained 80% - 84% of its initial efficiency after 3rd cycle of fermentation batches. One unit of α-amylase activity = 10 µg of reducing sugar per ml per min from soluble starch and one unit of APase =10 µg of para-nitrophenol formed per ml per min at 370C at pH 8.0.

Atypical central nervous system involvement in acute organophosphorous poisoning

Extrapyramidal syndrome is an uncommon sequelae of acute organophosphorous (OP) poisoning. It is a manifestation of the intermediate syndrome described in OP poisoning. It may or may not be associated with neuroimaging changes in the striatum. We present a case of acute OP poisoning with interesting positive CT scan findings.

Prevalence and significance of antiphospholipid antibodies in selected at-risk obstetrics cases: a comparative prospective study

In a prospective comparative study we screened 112 women with a past history either of pre-eclampsia, eclampsia, recurrent abortion, IUGR, IUFD or abruptio placentae, with no apparent aetiology and a demographically matched cohort of 106 women having a past history of uncomplicated pregnancy outcome for the presence of antiphospholipid antibodies (aPL) and their significance. In the former group, the prevalence of aPL ranged from 10-46.87% compared with 8.49% in the later group. In women with the presence of aPL, the incidence of pre-eclampsia, early onset pre-eclampsia and abruptio placentae were 25%, 14.58% and 18.75%, respectively. In the same group, the abortion rate was 25% and live-birth rate was 64.58% with IUFD rate of 10.42%. Fetal morbidity rates were also higher in the mothers with aPL positivity, the incidence of IUGR was 27.08% and oligohydramnios was 33.33% in them. All these complications were statistically significant when compared with those of aPL negative mothers.

Studies on intracellular degradation of polyhydroxyalkanoic acid–polyethylene glycol copolymer accumulated by Azotobacter chroococcum MAL-201

Azotobacter chroococcum MAL-201 accumulates poly(3-hydroxybutyric acid) [PHB] when grown in glucose containing nitrogen-free Stockdale medium. The same medium supplemented with valerate alone and valerate plus polyethylene glycol (PEG) leads to the accumulation of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [PHBV] and PEG containing PHBV-PEG polymers, respectively. The intracellular degradation of these polymers as studied in carbon-free Stockdale medium showed a rapid degradation of PHB followed by PHBV, while it was least in case of PHBV-PEG. The rate of such degradation was 44.16, 26.4 and 17.0 mg h(-1)l(-1) for PHB, PHBV and PHBV-PEG, respectively. During the course of such of PHBV and PHBV-PEG degradation the 3HB mol% of polymers decreased significantly with increase of 3HV mol fraction, the EG mol% in PHBV-PEG, however, remained constant. After 50h of degradation the decrease in intrinsic viscosity and molecular mass of PHBV-PEG were 37.5 and 43.6%, respectively. These values appeared low compared to PHB and PHBV. Moreover, the increasing EG content of polymer retarded their extent of degradation. Presence of PEG, particularly of low molecular weight PEG was inhibitory to intracellular PHA depolymerise (i-PHA depolymerase) activity and the relative substrate specificity of the i-PHA depolymerase of MAL-201 appeared to be PHB > PHBV > PHBV-PEG.

Incorporation of polyethylene glycol in polyhydroxyalkanoic acids accumulated by Azotobacter chroococcum MAL-201

Azotobacter chroococcum MAL-201 (MTCC 3853), a free-living nitrogen-fixing bacterium accumulates poly(3-hydroxybutyric acid) [PHB, 69% of cell dry weight (CDW)] when grown on glucose and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [PHBV with 19.2 mol% 3HV] when grown on glucose and valerate. Use of ethylene glycol (EG) and/or polyethylene glycols (PEGs) of low molecular weight as sole carbon source were detrimental to A. chroococcum growth and polymer yields. PEG-200, however, in the presence of glucose was incorporated into the polyhydroxyalkanoate (PHA) polymer. Addition of PEG-200 (150 mM) to culture medium during mid-log phase growth favored increased incorporation of EG units (12.48 mol%) into the PHB polymer. In two-step culture experiments, where valerate and PEG simultaneously were used in fresh medium, EG was incorporated most effectively in the absence of glucose, leading to the formation of a copolymer containing 18.05 mol% 3HV and 14.78 mol% EG. The physico-mechanical properties of PEG-containing copolymer (PHBV-PEG) were compared with those of the PHB homopolymer and the PHBV copolymer. The PHBV-PEG copolymer appeared to have less crystallinity and greater flexibility than the short-chain-length (SCL) PHA polymers.

Intracellular degradation of poly(3-hydroxybutyric acid) accumulated by Azotobacter chroococcum MAL-201

Azotobacter chroococcum MAL-201 accumulates poly(3-hydroxybutyric acid) [P(3HB)] accounting 69% of cell dry weight (CDW) from glucose during growth in nitrogen-free Stockdale medium. Degradation of the accumulated polymer by the organism was studied under carbon-free medium following two-step cultivation method. P(3HB) content of cells decreased rapidly from 69% to 4.8% of CDW after 35 h under carbon-deprived condition. Autodigestion of P(3HB) was evident from the estimation of intracellular P(3HB) depolymerase (i-depolymerase) activity in cell-free extract using artificial P(3HB) granules as substrate. Polymer content decreased rapidly along with the increase in i-depolymerase activity and rate of polymer degradation when medium was supplemented with (NH4)2SO4 at 0.1% (w/v) level. However, the effects were reverse when organic nitrogenous substrate, beef extract at similar concentration was present in the medium. The optimum temperature and pH for i-depolymerase activity were 35 degrees C and 7.7 respectively. The oxygen-limiting condition (culture volume per flask volume, 50%) decreased 10.7% activity of i-depolymerase over control resulting a slow P(3HB) degradation. The presence of NaCl (6 x 10(3) microg/ml) showed a positive effect on i-depolymerase whereas EDTA (40 microg/ml) resulted in 20% less activity. Furthermore, the intracellular degradation of P(3HB) decreased the intrinsic viscosity, molecular weight and tensile strength of the accumulated polymer.

Trigeminal neuralgia: current concepts and management

Trigeminal neuralgia is the most frequent cranial neuralgia, the incidence being 1 per 1,000,00 persons per year. It presents with stabbing pain often in the distribution of the mandibular and maxillary divisions of the trigeminal nerve. An accurate history of pain is important in the diagnosis of trigeminal neuralgia. A patient with tic douloureux and no neurological abnormality on clinical examination does not need diagnostic tests. The available options for management of trigeminal neuralgia are: Pharmacotherapy, destructive procedures and non-destructive procedures. The pharmacotherapy includes (i) monotherapy with one anticonvulsant, (ii) combined therapy with more than one anticonvulsant, (iii) add-on therapy with newer drugs and (iv) polytherapy with anticonvulsant + add-on drugs + antidepressants/anxiolytics. Destructive procedures include (i) non-surgical methods--injections along trigeminal pathways, percutaneous trigeminal radiofrequency thermocoagulation and (ii) surgical methods--trigeminal branch avulsion or peripheral neurectomy, avulsion of trigeminal nerve, trigeminal tractotomy, radiosurgery. Though various modalities of treatment are available for the management of trigeminal neuralgia, pharmacotherapy with carbamazepine still remains the first line of treatment. The alternative approach followed at most centres is percuatenous Gasserian rhizolysis (chemical/radiofrequency thermal) or microvascular decompression.

Giant pulmonary cyst simulating tension pneumothorax

Giant pulmonary cyst is a rare clinico-pathological entity. It was described as a "windy tumor" by John Floyer in 1726. Since that time, there have been numerous reports on this unique manifestation of emphysema by many authors. In this report, we report one such interesting case who was diagnosed as tension pneumothorax.

Visceral afferent hypersensitivity in irritable bowel syndrome--evaluation by cerebral evoked potential after rectal stimulation

OBJECTIVES

Gut hypersensitivity has been shown to be present in irritable bowel syndrome. The current study sought to determine the involvement or hypersensitivity of the gut afferents, objectively, by recording cerebral evoked potential after rectal stimulation.

METHODS

In 13 patients with irritable bowel syndrome and nine healthy controls, rectal perception thresholds to electrical stimulation were measured, and cerebral evoked potentials were recorded from 2 cm behind vertex (Cz') after rectal stimulation electrically (frequency 1 Hz, duration 0.5 ms) at an intensity 50% above perception threshold and with filter setting 1-250 Hz.

RESULTS

Perception thresholds to rectal electrical stimuli in patients with irritable bowel syndrome were lower than controls (p < 0.05). Rectal stimulation led to recognizable and reproducible cerebral evoked potentials. P1, N1, P2 latencies in patients with irritable bowel syndrome were shorter than that in controls (p < 0.05). P1/N1 amplitude was greater in patients with irritable bowel syndrome than in controls (p < 0.05).

CONCLUSIONS

The shorter latency and increased amplitude of cerebral evoked potential after rectal stimulation in patients with irritable bowel syndrome compared to controls provide objective evidence supporting visceral afferent hypersensitivity as the underlying mechanism in irritable bowel syndrome.

Clinical profile of multiple sclerosis in Bengal

Forty five patients of multiple sclerosis diagnosed on the basis of Poser's criteria from West Bengal were studied. The male-female ratio was 1:1.5, mean age of onset 31.83 years in male and 29.11 years in females. The maximum cases were between the 3rd and 4th decade. Definite MS comprised of 60%, while remaining 40% were probable. Visual impairment (53.33%), weakness of limbs (31.11%) and sensory paraesthesia (20%) were the common presenting symptoms whereas pyramidal tract involvement (93.33%) with absent abdominal reflexes (90%) and optic pallor (64.44%) were common signs. Posterior column and spinothalamic sensations were involved in 55% and 51% of cases respectively. Inter-nuclear ophthalmoplegia was present in 6.66% of cases. Pattern of involvement commonly showed three or more sites of lesion. Optico-spinal affection was present in 22.2% of cases. Relapsing and remitting course was found in 48. 91%, relapsing and progressive course in 33.33% and chronic progressive in 17.8%. MRI of brain showed positive results in 16 out of 23 cases. CSF study showed increased positivity in estimation of immunoglobulin level than oligoclonal band. Findings revalidate the disease pattern as being similar to that in other parts of India as well as Asia.

Profile of non-compressive myelopathy in eastern India: a 2-year study

Eighty-two patients with non-compressive myelopathy have been studied from July 1994 to June 1996 in Bangur Institute of Neurology and S.S.K.M. Hospital, Calcutta, of which 48 patients were men and 34 patients were women. Presentation was acute in 40 patients (48.78%), subacute in 7 (8.53%), chronic in 27 (32.92%) and history of relapse and remission in 8 (9.75%) patients. Preceding as well as simultaneous fever was observed in 16 cases (19.5%); vaccination (anti-rabies) in 1 case (1.21%); drug abuse in 1 case (1.21%); arthralgia-myalgia and rash in 2 cases (2.42%) and history of electrocution in 2 cases (2.42%). Only pyramidal tract involvement was present in 24 cases (29.26%) and remaining 58 cases (70.73%) had pyramidal tract affection with other sites of involvement. CSF study carried out in 60 cases, revealed rise of protein in 31 (37.8%); oligoclonal band had been detected in 6 (7.31%), pleocytosis in 18 cases (21.95%) and increased IgG index greater than 6.66 in 2 cases (2.42%). CT myelogram done in 23 cases revealed no abnormality. MRI study carried out in 59 cases showed myelomalacia in 1 (1.21%); demyelination plaque in 14 cases (17.07%); atrophy of cord in 3 (3.65%); infarction of cord in 1 (1.21%) and in 40 cases (48.78%) no abnormality could be detected. Etiological diagnosis could be established in 59 (71.95%) cases such as transverse myelitis or myelopathy (post infectious) in 24 (29.26%); demyelination in 16 (19.51%); vascular and vasculitis in 3 (3.65%); toxic in 1 (1.21%); physical (electrocution) in 2 cases (2.42%). In the remaining 23 cases (28.04%) no aetiological factors could be found.

Clinical profile of myasthenia gravis

Seventy three patients with myasthenia gravis were studied over 9 years period (1987-1995) in departments of neuromedicine, respiratory care unit, cardiothoracic unit of Institute of Postgraduate Medical Education and Research and Bangur Institute of Neurology, Calcutta, with reference to their clinical presentations, laboratory findings and various modes of treatment. Commonest age of presentation was 5th decade in men and 3rd decade in women. Fifty five percent of patients belong to type 2A myasthenia gravis (Osserman classification). Presentation was insidious (67.2%) and course was slowly progressive (65.7%) in majority of cases. Fatigability and ptosis were commonest clinical presentation and diurnal variation was noticed in 60% of cases. Edrophonium test was positive in 90.4% of cases and repetitive nerve stimulation showed 93.5% positivity in 30 cases. 27 patients (36.9%) underwent thymectomy and out of these, 89% of patients showed hyperplastic change and thymoma in 11% of cases. Mortality rate including both operated and nonoperated patients was recorded to be 9.6%. We observed earlier onset of myasthenia in male, higher incidence of oculo-bulbar involvement and lower incidence of respiratory problem and thymoma.

Surgical management of intrathoracic goiter

Intrathoracic goiter is a rare clinical entity. This goiter can develop slowly and the patient may be asymptomatic for many years. A significant number of these patients, however, may develop various complications as a result of compression of vital structures or malignancy. In this report, the surgical management of 18 cases of intrathoracic goiter are reviewed. Six of the patients underwent right thoracotomy with resection of the posterior mediastinal goiter. The remaining 12 patients had their tumor removed via median sternotomy. There were no surgical deaths within this series. Although the incidence of intrathoracic tumor is limited, the threat of malignancy and compressive symptoms clearly indicates the need for surgical excision. Our group recommends thoracotomy and median sternotomy for surgical excision.

Pattern of motor neurone disease in eastern India

A clinical study about the pattern of motor neurone disease in eastern India was carried out from July 1993 to June 1995 at Bangur Institute of Neurology, Calcutta and SSKM Hospital, Calcutta. A total of 110 cases were studied and they constituted 0.11% of all neurological cases seen in the general OPD. Of 110 cases, amyotropic lateral sclerosis (ALS) constituted 43.6%, progressive muscular atrophy (PMA) 10.9%, post-polio progressive muscular atrophy (PPMA) 1.8%, spinal muscular atrophy (SMA) 20%, atypical form Madras pattern of MND (MMND) 0.9% and monomelic amyotrophy (MMA) 22.7% of cases. Disease is more common in males than females and average duration of symptoms before presentation varied from 1 to 12 months. Most of the patients were either agricultural labourers or manual workers in ALS variety whereas MMA variety was evenly distributed in both hard labourers and sedentary workers. Most of the patients in MMA and SMA groups presented before 30 years of age whereas ALS and PMA group presented after 30 years. Trauma was the commonest antecedent event in ALS and MMA followed by electrocution in the same two groups. Family history was found to be absent in SMA group though the disease is considered as a hereditary one. Weakness of the limbs and wasting of the muscles were common presenting symptoms and signs. Bulbar symptoms and signs were found only in the ALS group. EMG showed neurogenic pattern and mixed pattern in most of the patients in all groups. Only a few patients showed myopathic pattern. Neuroimaging study helped in exclusion of compressive lesion excepting two cases of MMA where facetal hypertrophy was present. Monomelic amyotrophy, a special variety of motor neurone disease, is not rare in this part as compared to other parts of India and Asia.

Carotid endarterectomy in a community hospital

Despite the popularity of carotid endarterectomy, considerable debate remains regarding the appropriateness of these procedures. Critics of carotid endarterectomy cite the excessive morbidity and mortality associated with these procedures, particularly when performed in a community hospital setting. A retrospective study of 130 procedures, involving 124 patients within a medium size community hospital setting, was conducted. Indications for the procedure, associated comorbidities, and complication rates were reviewed. The incidence of stroke with subsequent mortality was 0.8% within the study group. One patient (0.8%) developed acute coronary insufficiency and underwent coronary artery bypass surgery. Five (4.0%) other patients experienced minor complications. Carotid endarterectomy is a proven prophylactic measure against the prevention of stroke in a selected group of patients. This study reinforces that this procedure may be performed in a community hospital setting with very low morbidity and mortality rates.

Disability pattern amongst leprosy cases in an urban area (Calcutta)

In a retrospective study of 1,264 leprosy cases, registered during 1987-1992, 282 were found to have disabilities giving a disability rate (DR) 22.31% and 150 of them were also found to have deformities, giving a deformity rate 11.9%. Mean disability index (DI) was found to be 1.17. Disability rate (DR) significantly increased with age and the highest rate was 52.75% in lepromatous (L) cases, followed by 27.51% in borderline (N?L) and only 4.53% in nonlepromatous (N) cases. L cases had the highest deformity rate (22.25%) and N cases had the lowest DR (2.23%). DI was highest (1.46) in L, and lowest (0.52) in N cases. Males had significantly higher DR (27.2%) compared to females (13.0%). Deformity in hands (42.55%) was more common than in feet (22.70%). Increasing trend of DI was noticed with increasing duration of disease in L and N?L types. The number of nerves involved was high (4.72) in L cases compared to other types. DI was highest (1.25) in patients engaged in occupations involving hard work.

Study of the characteristics and causes of relapse amongst leprosy cases in an urban area (Calcutta)

In this retrospective study of the 3737 cases of leprosy released from treatment and followed-up during 1975 to 1990, 63 had relapsed giving an overall relapse rate of 1.69%. The relapse rate was significantly higher in the immunologically unstable N?L (Borderline) cases (2.9%). It was also higher in those who had dapsone monotherapy (1.92%) compared to those who had multidrug therapy (1.01%). The relapse rate was higher in the 10 to 29 years age group and among those who became pregnant suggesting puberty and pregnancy could be risk factors. Males had a significantly higher relapse rate (2.1%) than females (1.1%). 45.2% of relapses in N (Non-lepromatous) cases occurred within 24 months and 71.4% within 36 months of stopping treatment. In those having monotherapy, 57.1% of relapses occurred within 24 months and 76.8% within 36 months. Regularity in treatment did not seem to have much influence on relapse rates.

Spontaneous pneumothorax in the newborn

Spontaneous pneumothorax is more frequent during the newborn period than at any other time in childhood. Intubation, vigorous resuscitation, aspiration of meconium-stained amniotic fluid, and hyaline membrane disease have been associated most often with the occurrence of spontaneous pneumothorax; however, it may occur in the absence of any of these precursors. Most pneumothoraces occur in term babies (64%); however, the premature infant is more susceptible. Signs and symptoms are due chiefly to lung compression and include grunting, tachypnea, cyanosis, and retraction. The accumulation of air serves as an intrathoracic space-occupying lesion, an emergency condition that demands prompt diagnosis and treatment.

Acute empyema in children treated by open thoracotomy and decortication

Acute nontuberculous empyema treated conventionally by thoracentesis, thoracostomy drainage, and antibiotics has an unacceptably high rate of morbidity and mortality. Early open thoracotomy to eliminate the empyema with decortication of the fibrinous peel and reexpansion of the lung has proven safe and effective for 25 years. The goals of treatment of acute nontuberculous empyema are: (1) to save life, (2) to eliminate the empyema, (3) to reexpand the trapped lung, (4) to restore mobility of the chest wall and diaphragm, (5) to return respiratory function to normal, (6) to eliminate complications or chronicity, and (7) to reduce the duration of hospital stay. Our studies confirm the normal values to be expected in patients who have had complete recovery from the acute empyema, and we lay to rest any concern that decortication might, in time, limit pulmonary function. We present the cases of 21 children who had acute and mature empyemas that were treated by open thoracotomy and decortication, with an average follow-up of 18 years, among whom there were no deaths or complications.

Surgical treatment of anterior diaphragmatic hernia

Of ten patients with anterior diaphragmatic hernia treated by operation, only three had shortness of breath and chest pain. The remainder of the patients were referred to us because of a roentgenographic abnormality. All patients have had follow-up of between six months and 11 years without recurrence. Surgical repair is recommended to prevent incarceration and strangulation.

Middle lobe syndrome: diagnosis and management

Ninety-eight patients with middle lobe syndrome were reviewed. There were 31 male and 67 female patients ranging in age from 4 to 80 years. The most common presenting symptoms were cough, dyspnea, fever, hemoptysis, and chest pain. Diagnostic studies included chest roentgenogram, bronchoscopy, and bronchography. Sixty-five patients had full recovery following intensive medical therapy. Thirty-one patients underwent surgical resection for persistent disease. There were five post-operative complications and 1 death in this series.

Histoplasmosis: clinical manifestations and surgical management

In this retrospective study of 115 cases of histoplasmids, there were 66 male and 49 female patients ranging in age from 2 months to 79 years. The most common presenting symptoms were cough, chest pain, wheezing, weight loss, hemoptysis, and shortness of breath. Thirty-five patients (30%) were asymptomatic. Two patients had manifestations of obstruction of the superior vena cava. Radiologic findings simulated carcinoma, tuberculosis, pneumonia, and viral infections. Sixty-five patients had various operative proceudres, such as lung biopsy, wedge resection, lobectomy, pneumonectomy, resection of lymph node, and bypass of superior vena cava, for diagnosis and treatment. There were two deaths and two postoperative complications. A total of 15 patients received intravenous amphotericin B. Four patients with pneumonic infiltrates developed disseminated histoplasmosis.

Hemodynamic effects of arteriovenous fistula and bovine graft fistula used for hemodialysis

This study shows that arteriovenous fistulas created for vascular access to hemodialysis result in an increase in cardiac output and pulse rate, and a decrease in the total peripheral resistance. These changes are severe with bovine graft fistula; physicians should be aware of this potentially dangerous hemodynamic change in these patients.

Objective assessment of femoral artery profundaplasty

The physiologic results after profundaplasty in a group of patients with uncorrected complete occlusion of superficial femoral artery are presented. The limbs were evaluated by ankle B.P. index and muscle pH, and pulse volume plethysmograph showed that the deep femoral artery, in occlusion of superficial femoral artery, can provide pulsatile flow and adequate perfusion to calf muscles in most cases.

Atrial myxoma. Clinical manifestations and surgical treatment

Four patients with atrial myxoma underwent successful surgical excision with the aid of cardiopulmonary bypass at the Medical University of South Carolina. This report describes their clinical manifestations and treatment with special emphasis on advances in surgical technique. This report also emphasizes the malignant potential of this tumor and reviews the recent literature.

Salvage of bovine graft arteriovenous fistula for hemodialysis

This report describes three patients with complications of bovine graft implanted for chronic dialysis. The three complications were surgically corrected so that each graft could be used again for hemodialysis access.

Reconstruction of the deep femoral artery

This article describes various surgical technics commonly used for reconstructing the deep femoral artery. The applicability, advantages, and disadvantages of various methods also are discussed.