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Biomedical subjects

V Mani

Publications and source records attributed to V Mani.

At least 19 recordsLinked to original sources
PubMed2004

The emergence of glycopeptide-resistant Enterococcus faecium in a university hospital in southwestern Greece.

BACKGROUND: Enterococci and especially glycopeptide-resistant strains (GRE) are widely distributed in the hospital environment, by acquiring resistance determinants and virulence factors. METHODS: The study included 48 GRE isolated during a 1-year period from different inpatients in a tertiary hospital in southwestern Greece. Antibiotic susceptibility was determined by the Etest, and the presence of resistance and virulence genes was shown by PCR. Clonal types were identified by pulsed-field gel electrophoresis of SmaI DNA digests. RESULTS: All GRE were multi-resistant of the VanA phenotype, verified by the detection of the gene by PCR. Two major clones were distributed in all hospital wards. The majority of the strains (46 of 48) harbored the esp gene, while 27 GRE expressed also the gelE and/or as genes. CONCLUSIONS: The spread of two clones expressing the vanA gene and virulence factors were responsible for the emergence of GRE in the University Hospital of Patras.

Anti-Bacterial Agents↗
PubMed2004

Decreased expression of apical Na+ channels and basolateral Na+, K+-ATPase in ulcerative colitis.

Impaired absorption of sodium (Na+) and water is a major factor in the pathogenesis of diarrhoea in ulcerative colitis (UC). Electrogenic Na+ absorption, present mainly in human distal colon and rectum, is defective in UC, but the molecular basis for this is unclear. The effect of UC on the expression of apical Na+ channels (ENaC) and basolateral Na+, K+-ATPase, the critical determinants of electrogenic Na+ transport, was therefore investigated in this study. Sigmoid colonic and/or proximal rectal mucosal biopsies were obtained from patients with mild to moderate UC, and patients with functional abdominal pain (controls). ENaC subunit expression was studied by immunohistochemistry, western blot analysis, and in situ hybridization, and Na+, K+-ATPase isoform expression was studied by immunohistochemistry, western blotting, and northern blot analysis. UC was associated with substantial decreases in the expression of the ENaC beta- and gamma-subunit proteins and mRNAs, whereas the decrease in ENaC alpha-subunit protein detected by immunolocalization was less marked. The levels of expression of Na+, K+-ATPase alpha1- and beta1-isoform proteins were also lower in UC patients than in controls, although there were no differences in Na+, K+-ATPase alpha1- and beta1-isoform mRNA levels between the two groups. Taken together, these results show that UC results mainly in decreased expression of the apical ENaC beta- and gamma-subunits, as well as the basolateral Na+, K+-ATPase alpha1- and beta1-isoforms. In conclusion, these changes provide a basis for the low/negligible levels of electrogenic Na+ absorption seen in the distal colon and rectum of UC patients, which contribute to the pathogenesis of diarrhoea in this disease.

Colitis, Ulcerative↗
PubMed2003

Versatility of temporalis myofascial flap in maxillofacial reconstruction--analysis of 30 cases.

Temporalis myofascial flap holds great promise for the reconstruction of various defects of the maxillofacial region-either congenital or surgical. The dependable blood supply through the middle and deep temporal arteries, proximity to the maxillofacial region, possibility to mobilize it to the oral cavity through the under surface of zygomatic arch and its fanned out nature permits the surgeon to use this flap for the reconstruction of various maxillofacial defects and even as an interposing tissue. In this series of 30 cases, we have used the temporalis myofascial flap for the reconstruction of different types of maxillofacial defects and as an interposing material in TMJ surgeries. We found that this flap is very valuable in maxillofacial reconstruction.

Ankylosis↗
PubMed2001

Death due to bioterrorism-related inhalational anthrax: report of 2 patients.

On October 9, 2001, a letter containing anthrax spores was mailed from New Jersey to Washington, DC. The letter was processed at a major postal facility in Washington, DC, and opened in the Senate's Hart Office Building on October 15. Between October 19 and October 26, there were 5 cases of inhalational anthrax among postal workers who were employed at that major facility or who handled bulk mail originating from that facility. The cases of 2 postal workers who died of inhalational anthrax are reported here. Both patients had nonspecific prodromal illnesses. One patient developed predominantly gastrointestinal symptoms, including nausea, vomiting, and abdominal pain. The other patient had a "flulike" illness associated with myalgias and malaise. Both patients ultimately developed dyspnea, retrosternal chest pressure, and respiratory failure requiring mechanical ventilation. Leukocytosis and hemoconcentration were noted in both cases prior to death. Both patients had evidence of mediastinitis and extensive pulmonary infiltrates late in their course of illness. The durations of illness were 7 days and 5 days from onset of symptoms to death; both patients died within 24 hours of hospitalization. Without a clinician's high index of suspicion, the diagnosis of inhalational anthrax is difficult during nonspecific prodromal illness. Clinicians have an urgent need for prompt communication of vital epidemiologic information that could focus their diagnostic evaluation. Rapid diagnostic assays to distinguish more common infectious processes from agents of bioterrorism also could improve management strategies.

Abdominal Pain↗
PubMed1999

Variation of spectral power immediately prior to spontaneous onset of ventricular tachycardia/ventricular fibrillation in implantable cardioverter defibrillator patients.

INTRODUCTION: Short-term heart rate variability (HRV) may change immediately before onset of a ventricular arrhythmia (ONSET). METHODS AND RESULTS: Power spectrum analysis was performed on instantaneous heart rate (IHR; including all beats) and normal heart rate (NHR; excluding ectopics) curves obtained at equally spaced 0.5-second intervals using a cubic spline. The database consisted of 135 sets of 1,024 RR intervals leading to ventricular arrhythmia (VA) and controls from 78 patients. Total periodogram and time course of spectral power were obtained. Ten spectral bands of 0.1-Hz bandwidth (0 to 1 Hz) were analyzed. A simple threshold technique was retrospectively used to predict the onset of a VA. RR intervals that led to VA ONSET had significantly higher total spectral power than controls (P < 0.001 for both NHR and IHR for every band). Spectral power remained constant until 100 seconds before ONSET and then increased significantly in the time window immediately preceding ONSET (P < 0.02 compared with others). Using a simple threshold method, a predictive accuracy of 68%+/-1.4% was obtained with different window sizes. Using specific spectral bands, the predictive accuracy of VA ONSET could be improved to 76% for IHR and 71% for NHR (0.8- to 0.9-Hz band). CONCLUSION: Our results suggest that a sustained higher power increase in NHR and IHR occurs during the course of 12.11+/-.57 minutes, followed by a sudden elevation in spectral power within 100 seconds of ONSET, and may be a precursor to ventricular tachycardia/ventricular fibrillation episodes.

Algorithms↗
PubMed1998

Coupled B-snake grids and constrained thin-plate splines for analysis of 2-D tissue deformations from tagged MRI.

Magnetic resonance imaging (MRI) is unique in its ability to noninvasively and selectively alter tissue magnetization and create tagged patterns within a deforming body such as the heart muscle. The resulting patterns define a time-varying curvilinear coordinate system on the tissue, which we track with coupled B-snake grids. B-spline bases provide local control of shape, compact representation, and parametric continuity. Efficient spline warps are proposed which warp an area in the plane such that two embedded snake grids obtained from two tagged frames are brought into registration, interpolating a dense displacement vector field. The reconstructed vector field adheres to the known displacement information at the intersections, forces corresponding snakes to be warped into one another, and for all other points in the plane, where no information is available, a C1 continuous vector field is interpolated. The implementation proposed in this paper improves on our previous variational-based implementation and generalizes warp methods to include biologically relevant contiguous open curves, in addition to standard landmark points. The methods are validated with a cardiac motion simulator, in addition to in-vivo tagging data sets.

Computer Simulation↗
PubMed1998

Clinical status of ulcerative colitis in patients who smoke.

OBJECTIVES: Ulcerative colitis (UC) is largely a disease of nonsmokers. There are few patients who are current smokers, but we have identified a group and reviewed their clinical status, disease activity, and nicotine exposure to examine whether they remain well controlled while smoking. METHODS: Fifty-one patients from three centers with verified UC were reviewed. RESULTS: Thirty of the group were men; mean age 50 yr, with a mean age of onset of 37 yr. Twenty-two patients had proctosigmoid disease, 12 involvement of left colon, and 17 total colitis. All were current smokers; 41 were cigarette smokers averaging 17 daily. At the onset of colitis 30 were nonsmokers, 25 of them were ex-smokers and 19 developed colitis within 2 yr of stopping smoking. Twenty-eight believed smoking improved disease activity and none felt smoking had a detrimental effect on their UC. Eleven were receiving no medication for UC, 40 were receiving 5-ASA (5-aminosalicylic acid) preparations, and only two took oral steroids. All were in clinical remission, with the exception of one patient; mean St. Marks score was 1.5, out of a possible total of 22. Sigmoidoscopic grades were inactive in all patients except three. Histological assessment showed significant activity in only five. Median serum nicotine was 8 ng/ml (range, 0.4-24.4), median serum cotinine 180 ng/ml (range, 20-453), with corresponding salivary cotinine of 255 ng/ml (range, 34-683). Median rise in nicotine 2 min after a cigarette in 35 patients was 12.1 ng/ml (range, 0.4-44). CONCLUSIONS: Because most current smokers with UC have inactive disease, smoking may contribute to the clinical remission in these patients.

Adult↗
PubMed1997

Effect of the Spreading Coefficient on Three-Phase Flow in Porous Media

A pore-level network model has been developed to study the effect of spreading coefficients on three-phase flow through porous media. This model combines the morphological description of the pore space with pore-level displacement physics to model capillarity-controlled, immiscible gas invasion of a porous medium initially saturated with water and oil. Three displacement events are involved during gas invasion, namely, direct water drainage, direct oil drainage, and double drainage. Direct oil drainage and double drainage involve oil mobilization and consequently lead to oil recovery. Direct water drainage event is preferred over double drainage if the spreading coefficient is highly negative. The residual oil saturation to gasflood starting after a waterflood is higher for nonspreading oils than for spreading oils. In spreading oils, it is not a function of the spreading coefficient. In nonspreading oils, the residual oil saturation increases with the magnitude of the spreading coefficient. The residual oil saturation to gasflood is also a function of the initial oil saturation; it increases as the initial oil saturation increases. The increase is higher for nonspreading oils. The gas-oil capillary pressure is not a function of the liquid saturation alone, as is commonly presumed. It is a function of the spreading coefficient and the initial oil saturation, as well.

Journal Article↗
PubMed1997

Antibiotic prophylaxis in gastrointestinal endoscopy: a report by a Working Party for the British Society of Gastroenterology Endoscopy Committee.

Antibiotic prophylaxis is recommended for endoscopic procedures if the patient is at high risk of endocarditis or of symptomatic bacteraemia as a consequence of immunosuppression or neutropenia. In most circumstances parenteral amoxycillin and gentamicin are recommended. The addition of parenteral metronidazole is recommended in patients with neutropenia. Vancomycin or teicoplanin are recommended in patients allergic to penicillin. Antibiotic prophylaxis is recommended for all patients undergoing ERCP with evidence of biliary stasis or pancreatic pseudocyst. Oral ciprofloxacin or parenteral gentamicin (or parenteral quinolone, cephalosporin or ureidopenicillin) are recommended for ERCP.

Administration, Oral↗
PubMed1996

A randomised trial comparing mesalazine and prednisolone foam enemas in patients with acute distal ulcerative colitis.

Distal ulcerative colitis can be treated with oral or rectal mesalazine, or both. A foam enema preparation has been developed and its efficacy investigated. The aim of this study was to evaluate the efficacy and safety of mesalazine foam enemas compared with prednisolone foam enemas in the treatment of patients with acute distal ulcerative colitis. Patients aged over 18 years presenting with a relapse of distal ulcerative colitis were randomly allocated treatment with mesalazine foam enema (n = 149 evaluable patients) and prednisolone foam enema (n = 146 evaluable patients) for four weeks. A randomised multicentre investigator blind parallel group trial was conducted. It was found that after four weeks of treatment, clinical remission was achieved by 52% of mesalazine treated patients and 31% of patients treated with prednisolone (p < 0.001). There was a trend in favour of more patients in the mesalazine group achieving sigmoidoscopic remission (40% v 31%, p = 0.10). Histological remission was achieved by 27% and 21% of patients receiving mesalazine and prednisolone respectively. Symptoms improved in both treatment groups. Significantly more mesalazine patients had no blood in their stools after four weeks of treatment (67% v 40%, p < 0.001). Prednisolone treated patients had significantly fewer days with liquid stools than mesalazine patients, with a median of 0 and 1 days respectively by week 4 (p = 0.001). In this study mesalazine foam enema was superior to prednisolone foam enema with regards to clinical remission, this was supported by favourable trends in sigmoidoscopic and histological remission rates. Both treatments were well tolerated.

Acute Disease↗
PubMed1996

Transdermal nicotine compared with oral prednisolone therapy for active ulcerative colitis.

BACKGROUND: Ulcerative colitis is largely a disease of non-smokers. Previous controlled trials have shown benefit with transdermal nicotine when given with 5-aminosalicylic acid in active disease but not when given alone as maintenance therapy. OBJECTIVE: To examine nicotine alone compared with prednisolone in active disease. PATIENTS AND METHODS: Sixty-one patients with active ulcerative colitis were treated with either transdermal nicotine patches or 15 mg prednisolone for 6 weeks in a randomized, double-blind study. Incremental doses of nicotine were given for the first 9 days; patients tolerated between 15 and 25 mg daily. Most patients were taking mesalazine at entry which was discontinued at day 10; a few were taking topical steroids which were discontinued at the onset. Clinical, sigmoidoscopic and histological assessments were made at baseline and 6 weeks, or at premature withdrawal. Symptoms were recorded on a diary card, and the clinician made a global clinical assessment. Side effects and serum nicotine and cotinine concentrations were monitored throughout the study. RESULTS: Forty-three patients completed the 6-week trial; of these, 6 of 19 in the nicotine group achieved full sigmoidoscopic remission compared with 14 of 24 with prednisolone (P = 0.08). In those who completed the 6-week study, there was significant improvement within both the nicotine and prednisolone group for the St Mark's score (P < 0.05 and P < 0.01, respectively), Global Clinical Grade (P < 0.01 for both), blood in the stool (P < 0.05 and P < 0.01), abdominal pain (P < 0.05 and P < 0.01) and sigmoidoscopic score (P < 0.01 and P < 0.001); differences between groups tend to favour prednisolone, but none reach statistical significance. However, on intention-to-treat analyses there is little clear evidence of improvement in either group apart from sigmoidoscopic score in which prednisolone was associated with a significantly greater improvement than nicotine (P < or = 0.05). The nicotine group had more withdrawals than the prednisolone group, 11 versus 7, respectively (P = 0.23), both for deterioration (6 vs. 5) and side effects (5 vs. 2, P = 0.15). Side effects were more frequently reported in the nicotine group (average 1.47 episodes per person) than the prednisolone group (average 0.61; P = 0.03), the most common of which were nausea, light-headedness and tremor. CONCLUSION: In those who managed to complete the 6-week study, nicotine alone appeared to be of only very modest benefit in acute colitis and was not as effective as 15 mg of prednisolone daily.

Administration, Cutaneous↗
PubMed1995

Transdermal nicotine as maintenance therapy for ulcerative colitis.

BACKGROUND: Ulcerative colitis is largely a disease of nonsmokers. Having found previously that treatment with transdermal nicotine patches and mesalamine (5-aminosalicylic acid) has a beneficial effect on active colitis, we examined the value of transdermal nicotine for the maintenance of remission. METHODS: We treated 80 patients with ulcerative colitis in remission with either transdermal nicotine or placebo patches for six months in a randomized, double-blind study. Incremental doses of nicotine were given for the first three weeks to achieve a maintenance dose; most patients tolerated 15 mg for 16 hours daily. All patients were taking mesalamine preparations as maintenance treatment at entry into the study; this treatment was stopped once the maintenance dose of nicotine was achieved. Clinical, sigmoidoscopic, and histologic assessments were made at the beginning and the end of the study, or at relapse. Side effects and serum nicotine and cotinine concentrations were monitored throughout the study. RESULTS: There was no significant difference in the number of relapses between the groups. Twenty-two patients in the nicotine group were prematurely withdrawn from the study, 14 because of relapse and 8 for other reasons, including side effects and protocol violations. In the placebo group, 20 patients were withdrawn prematurely, 17 because of relapse and 3 for other reasons. Among patients using 15-mg nicotine patches, serum nicotine and cotinine concentrations were lower than expected and may reflect poor compliance. Side effects were reported by 35 patients--21 in the nicotine group and 14 in the placebo group--the most common of which were nausea, lightheadedness, and itching. CONCLUSIONS: Transdermal nicotine alone was no better than placebo in the maintenance of remission of ulcerative colitis, and premature withdrawal due to side effects was more common in the nicotine group.

Administration, Cutaneous↗
PubMed1994

Transdermal nicotine for active ulcerative colitis.

BACKGROUND: Ulcerative colitis is largely a disease of nonsmokers. Because anecdotal reports suggest that smoking and nicotine may improve the symptoms of the disease, we examined the effect of nicotine as a supplemental treatment for ulcerative colitis. METHODS: We treated 72 patients with active ulcerative colitis with either transdermal nicotine patches or placebo patches for six weeks in a randomized, double-blind study. Incremental doses of nicotine were given; most patients tolerated doses of 15 to 25 mg per 24 hours. All the patients had been taking mesalamine, and 12 were receiving low doses of glucocorticoids; these medications were continued without change during the study. Clinical, sigmoidoscopic, and histologic assessments were made at base line and at the end of the study; symptoms were recorded daily on a diary card, and the clinician made a global assessment. Side effects and plasma nicotine and cotinine concentrations were monitored throughout the study. RESULTS: Seventeen of the 35 patients in the nicotine group had complete remissions, as compared with 9 of the 37 patients in the placebo group (P = 0.03). The patients in the nicotine group had greater improvement in the global clinical grade of colitis (P < 0.001) and the histologic grade (P = 0.03), lower stool frequency (a difference of 1.6 stools daily; P = 0.008), less abdominal pain (P = 0.05), and less fecal urgency (P = 0.009). More patients in the nicotine group had side effects (23, vs. 11 in the placebo group; P = 0.002), the most common of which were nausea, lightheadedness, headache, and sleep disturbance. Withdrawals due to ineffective therapy were more common in the placebo group (3 vs. 8, P = 0.12). CONCLUSIONS: The addition of transdermal nicotine to conventional maintenance therapy improves symptoms in patients with ulcerative colitis.

Administration, Cutaneous↗
PubMed1993

Comparison of bismuth citrate and 5-aminosalicylic acid enemas in distal ulcerative colitis: a controlled trial.

An enema that contained a complex of bismuth citrate and polyacrylate was compared with 5-aminosalicylic acid (5-ASA) enemas for treatment of distal ulcerative colitis. The multicentre trial involving 63 patients was randomised and double blind with enemas given over four weeks; clinical, sigmoidoscopic, and histological assessments were made. Improvements were seen in both treatment groups. Clinical remission was seen in 18 of 32 patients treated with 5-ASA and 12 of 31 patients treated with bismuth citrate-carbomer (chi 2 1.94; p = 0.16). Sigmoidoscopic remission occurred in 20 of 32 patients in the 5-ASA group and 15 of 31 patients given bismuth (chi 2 1.27; p = 0.26). Improvement of rectal biopsy histology by at least one grade was seen in 16 of 32 patients in the 5-ASA group and 14 of 31 patients with bismuth (chi 2 0.15; p = 0.70). Analysis of covariance gave no significant difference between groups, although there was a trend favouring 5-ASA. There was no evidence of bismuth accumulation during the trial. Bismuth enemas may offer a new therapeutic option in distal ulcerative colitis.

Adult↗
PubMed1992

Identification of an abnormal esophageal clearance response to intraluminal distention in patients with esophagitis.

Esophageal clearance responses were studied by a new technique comprising a miniature electronic strain gauge attached to an inflatable balloon in 30 normal volunteers and 48 patients with gastroesophageal reflux disease. The pressure changes around the balloon and traction forces acting on the balloon were measured during graded balloon distention (0-12 mL of air for 30 seconds each inflation) in the lower and midesophagus. All normal volunteers responded to distention with development of swallow independent contractions above the balloon [65 mm Hg/30 s (range, 45-100 mm Hg/30 s)] together with generation of an aboral traction force [15 g (range, 9-20 g)]. Patients with reflux esophagitis showed a higher distention threshold for initiation of these responses, induced fewer proximal contractions [24 mm Hg/30 s (range, 0-38 mm Hg/30 s); P less than 0.01 vs. normal], and generated weaker traction forces [4 g (range, 0-6 g) at 10 mL P less than 0.01 vs. normal]. Patients with the most severe esophagitis showed greatest impairment of the clearance response (correlation = 0.7, P less than 0.01) and the greatest esophageal residence of refluxed acid (correlation = 0.5, P less than 0.01). These abnormalities appear to be of relevance to the pathophysiology of esophageal reflux disease although it remains to be determined whether they are the cause, or the result, of the esophagitis.

Adolescent↗
PubMed1992

Tests of renal function in patients with quiescent colitis: effects of drug treatment.

Mesalazine has structural similarities to aspirin and phenacetin and is nephrotoxic when given intravenously in high doses to rats. A number of cases of nephrotoxicity has been reported recently in patients taking oral mesalazine. Sensitive indicators of renal function in a group of patients maintained on long term, delayed release mesalazine and a comparable group on sulphasalazine have been studied. Sixty two patients (32 men, aged 28-82 years) with quiescent colitis were studied. Thirty four had been maintained on delayed release mesalazine 1.6 (0.8-2.4) g/day for 2.9 (0.5-6.9) years and 28 on sulphasalazine 2 (2-3) g/day. Groups were comparable for age, sex, disease duration, and disease extent. Renal function was assessed by: urine microscopy; creatinine clearance; the urinary excretion of two markers of glomerular toxicity, albumin and transferrin; and the urinary excretion for two markers of tubular toxicity, N-acetyl-beta-D-glucosaminidase (NAG) and alpha 1-microglobulin. There were no significant differences in renal function between the two treatment groups. Furthermore, no correlations were found between measures of renal function and either cumulative mesalazine dose or mesalazine treatment duration. In this study, long term maintenance treatment with delayed release mesalazine was no more nephrotoxic than continued treatment with sulphasalazine.

Adult↗
PubMed1991

Design of a helix-bundle cross-link: NMR and UV-visible spectroscopic analyses and molecular modeling of ring-oxidized retinals.

In order to generate potential chemical cross-links for studying the chromophore binding site of bacteriorhodopsin and related helix-bundle proteins, MnO2 was used to oxidize all-trans-retinal's ring moiety. The structures and solution conformations of three ring-oxidized retinal analogues have been determined by using UV-visible absorption and 1H and 13C NMR spectroscopies, primarily with regard to (i) the introduction of a functional group at the ring end of the chromophore, (ii) the retention of the all-trans geometry of the polyenal side chain, and (iii) the torsional angle of the ring-polyenal bond. Analyses of their UV-visible absorption spectral parameters (lambda max, epsilon max, and vibrational fine structure) and NMR spectral parameters (1H-1H coupling constants, 1H and 13C NMR chemical shifts, and 1H homonuclear Overhauser effects) indicated the 4-oxo and the 2,3-dehydro-4-oxo derivatives both possess the twisted 6-s-cis conformation adopted by most six-membered ring analogues of retinal in solution or crystal. However, the alpha-dioxocyclopentenyl analogue exists in solution predominantly (70-80%) as the planar 6-s-trans conformer, similar to violerythrine chromophore analogues. In order to identify the minor solution forms, molecular modeling and geometry optimizations using the semiempirical molecular orbital method AM1 defined two additional symmetry-related minima at +/- 30-40 degrees in its C6-C7 torsional energy profile. Because the chromophores of bacterio- and halorhodopsins and sensory rhodopsins are bound as the 6-s-trans conformer [Harbison, G.S., Smith, S.O., Pardoen, J.A., Courtin, J.M.L., Lugtenburg, J., Herzfeld, J., Mathies, R.A., & Griffin, R.G. (1985) Biochemistry 24, 6955-6962; Baselt, D.R., Fodor, S.P.A., van der Steen, R., Lugtenburg, J., Bogomolni, R.A., & Mathies, R.A. (1989) Biophys. J. 55, 193-196], we suggest that the cyclopentenyl analogue's alpha-diketo function may be favorably positioned within the binding pocket and sufficiently reactive toward nucleophilic attack to cross-link an arginine located in or near the ring end of the chromophore cavity: Arg134 according to the current model of bacteriorhodopsin's tertiary structure [Henderson, R., Baldwin, J.M., Ceska, T.A., Zemlin, F., Beckmann, E., & Downing, K.H. (1990) J. Mol. Biol. 213, 899-929] or Arg82 as postulated from an alternate model constructed primarily to accommodate the external point charge contribution to bacteriorhodopsin's opsin shift.

Bacteriorhodopsins↗