Analysing the outbreaks of leptospirosis after floods in Kerala, India.

A growing number of studies have linked the incidence of leptospirosis with the occurrence of flood events. Nevertheless, the interaction between flood and leptospirosis has not been extensively studied to understand the influence of flood attributes in inducing new cases. This study reviews leptospirosis cases in relation to multiple flood occurrences in Kerala, India. Leptospirosis data were obtained for three years: 2017 (non-flood year) and two years with flooding-2018 (heavy flooding) and 2019 (moderate flooding). We considered the severity of flood events using the discharge, duration and extent of each flooding event and compared them with the leptospirosis cases. The distribution of cases regarding flood discharge and duration was assessed through descriptive and spatiotemporal analyses, respectively. Furthermore, cluster analyses and spatial regression were completed to ascertain the relationship between flood extent and the postflood cases. This study found that postflood cases of leptospirosis can be associated with flood events in space and time. The total cases in both 2018 and 2019 increased in the post-flood phase, with the increase in 2018 being more evident. Unlike the 2019 flood, the flood of 2018 is a significant spatial indicator for postflood cases. Our study shows that flooding leads to an increase in leptospirosis cases, and there is stronger evidence for increased leptospirosis cases after a heavy flood event than after a moderate flooding event. Flood duration may be the most important factor in determining the increase in leptospirosis infections.

Dengue risk zone mapping of Thiruvananthapuram district, India: a comparison of the AHP and F-AHP methods.

Dengue fever, which is spread by Aedes mosquitoes, has claimed many lives in Kerala, with the Thiruvananthapuram district bearing the brunt of the toll. This study aims to demarcate the dengue risk zones in Thiruvananthapuram district using the analytical hierarchy process (AHP) and the fuzzy-AHP (F-AHP) methods. For the risk modelling, geo-environmental factors (normalized difference vegetation index, land surface temperature, topographic wetness index, land use/land cover types, elevation, normalized difference built-up index) and demographic factors (household density, population density) have been utilized. The ArcGIS 10.8 and ERDAS Imagine 8.4 software tools have been used to derive the risk zone maps. The area of the risk maps is classified into five zones. The dengue risk zone maps were validated using dengue case data collected from the Integrated Disease Surveillance Programme portal. From the receiver operating characteristic (ROC) curve analysis and the area under the ROC curve (AUC) values, it is proved that the F-AHP method (AUC value of 0.971) has comparatively more prediction capability than the AHP method (AUC value of 0.954) in demarcating the dengue risk zones. Also, based on the comparison of the risk zone map with actual case data, it was confirmed that around 82.87% of the dengue cases occurred in the very high and high-risk zones, thus proving the efficacy of the model. According to the dengue risk map prepared using the F-AHP model, 9.09% of the area of Thiruvananthapuram district is categorized as very high risk. The prepared dengue risk maps will be helpful for decision-makers, staff with the health, and disaster management departments in adopting effective measures to prevent the risks of dengue spread and thereby minimize loss of life.

Flood vulnerability of a few areas in the foothills of the Western Ghats: a comparison of AHP and F-AHP models.

Flooding is one of the most destructive natural catastrophes that can strike anywhere in the world. With the recent, but frequent catastrophic flood events that occurred in the narrow stretch of land in southern India, sandwiched between the Western Ghats and the Arabian Sea, this study was initiated. The goal of this research is to identify flood-vulnerable zones in this area by making the local self governing bodies as the mapping unit. This study also assessed the predictive accuracy of analytical hierarchy process (AHP) and fuzzy-analytical hierarchy process (F-AHP) models. A total of 20 indicators (nine physical-environmental variables and 11 socio-economic variables) have been considered for the vulnerability modelling. Flood-vulnerability maps, created using remotely sensed satellite data and geographic information systems, was divided into five zones. AHP and F-AHP flood vulnerability models identified 12.29% and 11.81% of the area as very high-vulnerable zones, respectively. The receiver operating characteristic (ROC) curve is used to validate these flood vulnerability maps. The flood vulnerable maps, created using the AHP and F-AHP methods, were found to be outstanding based on the area under the ROC curve (AUC) values. This demonstrates the effectiveness of these two models. The results of AUC for the AHP and F-AHP models were 0.946 and 0.943, respectively, articulating that the AHP model is more efficient than its chosen counterpart in demarcating the flood vulnerable zones. Decision-makers and land-use planners will find the generated vulnerable zone maps useful, particularly in implementing flood mitigation plans.

Global COVID-19 Transmission and Mortality-Influence of Human Development, Climate, and Climate Variability on Early Phase of the Pandemic.

Many of the respiratory pathogens show seasonal patterns and association with environmental factors. In this article, we conducted a cross-sectional analysis of the influence of environmental factors, including climate variability, along with development indicators on the differential global spread and fatality of COVID-19 during its early phase. Global climate data we used are monthly averaged gridded data sets of temperature, humidity and temperature anomaly. We used Human Development Index (HDI) to account for all nation wise socioeconomic factors that can affect the reporting of cases and deaths and build a stepwise negative binomial regression model. In the absence of a development indicator, all environmental variables excluding the specific humidity have a significant association with the spread and mortality of COVID-19. Temperature has a weak negative association with COVID-19 mortality. However, HDI is shown to confound the effect of temperature on the reporting of the disease. Temperature anomaly, which is being regarded as a global warming indicator, is positively associated with the pandemic's spread and mortality. Viewing newer infectious diseases like SARS-CoV-2 from the perspective of climate variability has a lot of public health implications, and it necessitates further research.

Biochemical and molecular dissection of thermo-sensitive genetic male sterility in diploid cotton (Gossypium arboreum L).

Diploid cotton, due to its inherent problem of stamen brittleness, its found unsuitable for traditional method of hybrid seed production which involves hand emasculation followed by pollination. Due to shortfall in other methods viz., Genetic Male Sterility (GMS), as well as, Cytoplasmic Genetic Male Sterility (CGMS), hybrid seed production in diploid cotton becomes costly and thereby, covers less area among the total cotton grown area. Thermo-sensitive genetic male sterility, which overcomes the drawbacks of both GMS and CGMS can be an effective tool in coming years for hybrid cotton research. Understanding fertility and sterility variations, their relation with biochemical changes in plant is important before its application in plant breeding. Hence, the available TGMS line, Ga TGMS-3 obtained at Cotton Research Centre, UAS, Dharwad was studied for callase activity and markers associated with TGMS. The line Ga TGMS-3 had fertile anthers and showed less callase enzyme activity at pre-meiosis stage, high enzyme activity at tetrad releasing microspore stage and no callase activity during other stages. The counterpart TGMS sterile anthers displayed little higher callase activity at pre-meiosis stage, high activity at tetrad stage, but poor activity at tetrad releasing microspore stage. During tetrad stage, TGMS sterile anthers showed high callase enzyme activity giving every chance for early release of poorly developed microspores as compared to fertile anthers. At tetrad releasing microspores stage during which fertile anthers had strong callase enzyme activity led to microspores being released normally and developed normal pollen grains as compared to sterile anthers. The present investigation revealed that NAU2176, NAU2096 and BNL1227 primers can be used as tightly linked markers for TGMS trait, as evident from their differential expression in fertile and sterile anthers.

Incidence of microemboli and correlation with platelet inhibition in aneurysmal flow diversion.

Flow-diverting stents have been associated with embolic and hemorrhagic complications, but the rate of procedure-related microemboli is unknown. Using transcranial Doppler sonography, we measured the rate of microemboli in 23 patients treated with flow-diverting stents. Patients received preprocedural dual antiplatelet medications and intraprocedural heparinization. Point-of-care platelet reactivity testing was performed before the procedure, and nonresponders (>213 P2Y12/ADP receptor reactivity units) received additional thienopyridine. Transcranial Doppler sonography was performed within 12-24 hours. Microemboli were detected in 3 patients (13%), 2 of whom were initially nonresponders. There was no association between the presence of microemboli and procedural or neurologic complications, aneurysm size, number of stents, or procedure time. Eight procedures (34.8%) required additional thienopyridine for inadequate platelet inhibition, and 3 required further treatment for persistent nonresponse to point-of-care platelet reactivity testing. There were 6 technical and 2 postoperative complications; none were associated with inadequate platelet inhibition or microemboli. The combination of routine point-of-care platelet reactivity testing and postprocedural microembolic monitoring may help identify patients at risk for thromboembolic complications after flow-diverting stents.

A cross-sectional study of visual impairment in elderly population in residential care in the South Indian state of Andhra Pradesh: a cross-sectional study.

OBJECTIVE: To assess the prevalence and major causes of visual impairment (VI) in elderly residents of 'home for the aged' institutions in the Prakasam district in India. DESIGN: Cross-sectional study. SETTING: 'Home for the aged' institutions in the Prakasam district in the South Indian state of Andhra Pradesh. PARTICIPANTS: All 524 residents in the 26 'homes for aged' institutions in the district were enumerated. PRIMARY AND SECONDARY OUTCOME MEASURES: Prevalence and causes of VI; visual acuity (VA) was assessed using a Snellen chart at a distance of 6 m. Pinhole VA was assessed if presenting VA was <6/18. Torchlight examination and direct ophthalmoscopy were performed. VI was defined as presenting VA <6/18 in the better eye. RESULTS: Of the 494 participants examined (response rate 94.3%), 78.1% were women, 72.1% had no formal schooling. The mean age of participants was 70 years (SD ±8.6 years). VI was present in 280/494 individuals (56.9%; 95% CI 52.3 to 61.3). Over 80% of the VI was due to avoidable causes including cataract (57.1%) and uncorrected refractive errors (26.4%). Among 134 individuals who had undergone bilateral cataract surgery, only 78 (58.2%) individuals had presenting VA ≥6/18 and 13/134 (9.7%) participants were blind. CONCLUSIONS: There is high prevalence of VI in the institutionalised elderly population in the Prakasam district in India. A significant proportion of this elderly population with VI can benefit from spectacles and cataract surgery. Strategies are required to provide high-quality services to this population.

Endovascular management of cerebral bypass graft problems: an analysis of technique and results.

BACKGROUND AND PURPOSE: Cerebral bypass grafts may develop generalized graft narrowing or focal stenosis during the perioperative period or later. Endovascular techniques such as PTA and stent placement of graft vessels are potential treatment options. Our objective was to review the safety, indications, technique, and results of endovascular management of graft problems. MATERIALS AND METHODS: All patients with cerebral bypass procedures by using graft vessels from 2005 to 2009 were identified from a prospective registry and were studied retrospectively. Patient characteristics, bypass procedures, indications for endovascular interventions, graft patency, and clinical outcomes were reviewed from medical charts and imaging records. RESULTS: A total of 79 patients underwent bypass procedures by using graft vessels. Seven patients of this group underwent endovascular interventions for the treatment of graft narrowing. Four of the 7 patients were treated for graft narrowing in the perioperative period (<1 month) with PTA; and 3 of the 7 patients, for late stenosis, 2 with PTA alone and 1 with PTA followed by stent placement. All procedures were immediately successful in improving flow through the graft. In late stenosis, PTA alone provided temporary improvement followed by recurrence, whereas PTA with a stent procedure was effective in the 1 patient long term. CONCLUSIONS: PTA is safe and effective in the management of graft spasm in the perioperative period. For late graft stenosis, PTA alone provides only temporary respite, while PTA with stent placement may be an effective solution.

A comparative study of temporary splints: bonded polyethylene fiber reinforcement ribbon and stainless steel wire + composite resin splint in the treatment of chronic periodontitis.

UNLABELLED: The present clinical study was undertaken to determine the effects of splinting overunsplinted mobile teeth following periodontal surgery and compared the efficacy of two splinting materials, i.e. Ribbond ribbon + Composite with Stainless steel wire + Composite. MATERIALS AND METHODS: Total of 30 patients (20 experimental and 10 control) formed the study group. Entire study was extended over a period of 12 weeks for each patient and treatment plan was divided into 8 phases. Healing response was monitored and application, durability, biocompatibility of splint material was assessed. RESULTS: Splint had a promising and beneficial effects on anterior teeth exhibiting Grade I to Grade II degrees of mobility. Experimental group showed a greater reduction in tooth mobility compared to control group. There was no significant difference in plaque index and Ribbond Ribbon reinforced with composite resin was an excellent material for application, patient comfort, resistance to fracture, biocompatable and esthetic acceptability. CLINICAL SIGNIFICANCE: Splinting is recommended as an adjunct to periodontal surgery in the treatment of hypermobile teeth, especially in cases where patient discomfort is a prominent factor.

FACT-MNG: tumor site specific web-based outcome instrument for meningioma patients.

To formulate Functional Assessment of Cancer Therapy-Meningioma (FACT-MNG), a web-based tumor site-specific outcome instrument for assessing intracranial meningioma patients following surgical resection or stereotactic radiosurgery. We surveyed the relevant literature available on intracranial meningioma surgery and subsequent outcomes (38 papers), making note of which, if any, QOL/outcome instruments were utilized. None of the surgveyed papers included QOL assessment specific to tumor site. We subsequently developed questions that were relevant to the signs and symptoms that characterize each of 11 intracranial meningioma sites, and incorporated them into a modified combination of the Functional Assessment of Cancer Therapy-Brain (FACT-BR) and SF36 outcome instruments, thereby creating a new tumor site-specific outcome instrument, FACT-MNG. With outcomes analysis of surgical and radiosurgical treatments becoming more important, measures of the adequacy and success of treatment are needed. FACT-MNG represents a first effort to formalize such an instrument for meningioma patients. Questions specific to tumor site will allow surgeons to better assess specific quality of life issues not addressed in the past by more general questionnaires.

Outcomes of ruptured intracranial aneurysms treated by microsurgical clipping and endovascular coiling in a high-volume center.

BACKGROUND AND PURPOSE: The purpose of this study was to analyze the 3-month outcomes of patients with aneurysmal subarachnoid hemorrhage (SAH) treated from January 2005 to June 2006. This paper describes the outcomes after treatment of aneurysmal SAH and comparison between patients treated by clipping or coiling in a high volume center. MATERIALS AND METHODS: A retrospective chart review was performed of records of 195 consecutive patients with SAH. The overall outcome and the pretreatment variables predicting outcomes and the difference between the clipping and coiling groups were analyzed by logistic regression analysis. RESULTS: A total of 105 (55%) patients had microsurgical clipping and 87 (45%) had endovascular coiling. At 3 months, 69% of patients recovered with no or mild disability. The predictors of a 3-month modified Rankin Scale (mRS) were Hunt and Hess (HH) grade on admission and the presence of intracerebral hemorrhage (ICH). Patients in the coiling group had worse admission grades; they had worse 3-month mRS (2.28 vs 1.73), but this was not significant when the groups were matched (P = .38). Vasospasm rate was significantly higher in the clipping group (66% vs 52%). The immediate incomplete occlusion rate of aneurysms was higher (21.7% vs 7.6%) in the coiling group. CONCLUSION: The overall results of treatment of aneurysmal SAH have improved. There is no significant difference in the outcomes between the patients in the clipping and coiling groups.

Outcome analysis of preoperative embolization in cranial base surgery.

OBJECTIVE: Management of cranial base tumors requires an interdisciplinary approach. Supraselective angiography and embolization is an important adjunct to cranial base surgery. Though successful embolization facilitates resection, the morbidity of this procedure remains poorly defined. Therefore, we set out to define the morbidity associated with embolization of skull base meningiomas, thus allowing for informed decision making when considering this adjunct to tumor resection. METHODS: A retrospective analysis was performed on our experience with embolization of 167 cranial base meningiomas. Cranial base meningiomas were defined as tumors originating from the olfactory groove, tuberculum sella, medial sphenoid wing, petro-clival region or foramen magnum. RESULTS: 280 feeding vessels were embolized with an average of 1.7 vessels per lesion. In 91% of patients embolized, good to excellent embolization was achieved without permanent neurological sequelae. In 20 patients no embolization was attempted due to the risk of new neurologic deficits or lack of an appropriate vessel for embolization. Twenty-one patients (12.6%) had transient worsening of their neurologic exam or a medical complication requiring hospitalization. Fifteen patients (9%) experienced permanent neurologic deficits or medical morbidity as a result of embolization. Four of the patients who experienced major complications had a decline in previously compromised cranial nerve function. CONCLUSIONS: Embolization of cranial base tumors is an important part of the therapeutic armamentarium for the treatment of cranial base lesions. Recognition of the morbidity of this procedure will allow for the most appropriate use of this powerful adjunct to cranial base surgery.

Brain stem cavernoma excised by subtemporal-infratemporal approach.

Brain stem cavernomas are most safely removed through the pial surface at which the cavernoma is surfacing. When a lower pontine or an upper medullary cavernoma comes to the surface of the anterior portion of the brain stem, it is difficult to reach by traditional approaches. We describe a case of mid- and lower pontine cavernoma, surfacing anteriorly, which was completely excised by the subtemporal-infratemporal approach. After making a small temporal craniotomy and a zygomatic osteotomy, the petrous carotid artery was mobilized anteriorly and the petroclival bone was drilled away to reach the anterior surface of the pons using the subtemporal-infratemporal approach. A small incision was made on the anterior surface of the pons, between the CN V and CN VI and the cavernoma was completely excised with the aid of the surgical microscope and the neuro-endoscope. Immediately after the operation, the patient had a complete abducens palsy and a mild increase of left hemiparesis, both of which resolved completely within 3 months. The patient returned to the full time work without any neurological deficit. A follow-up MRI 1 year later showed the complete excision of the cavernoma. The subtemporal-infratemporal approach is useful for anteriorly located mid to lower pontine and upper medullary cavernomas.

Posterior fossa meningiomas: surgical experience in 161 cases.

BACKGROUND: We report the clinical, radiological, and surgical findings of patients with posterior fossa meningiomas surgically treated at our institution over the last 6 years. METHODS: We reviewed 161 consecutive cases of posterior fossa meningiomas operated on between April 1993 and April 1999 at The George Washington University Medical Center. RESULTS: There were 128 female and 33 male patients (mean age 47 years, range of 10-81 years). Meningiomas were classified as petroclival (110 cases), foramen magnum (21 cases), cerebellar hemispheric, lateral tentorial (14 cases), cerebellopontine angle (9 cases), and jugular foramen (7 cases). Mean tumor equivalent diameter (TED) = (D1xD2xDE)(1/3) was 3.1 cm (range of 0.53-8.95). Head pain (50% of cases) and disturbance of gait (44%) were the most common presenting symptoms, and cranial neuropathies the most common neurological signs on admission. Mean preoperative performance status (Karnofsky scale) was 80.2 (range 40-100). Surgical approaches to these tumors included partial labyrinthectomy petrous apicectomy, fronto-temporal/fronto-temporal orbitozygomatic osteotomy, retrosigmoidal, extreme lateral, transpetrosal, and combined. In 38 cases a staged procedure was performed. Gross-total resection was achieved in 57% of patients, and subtotal/partial in 43%. Surgical mortality was 2.5% and complications were encountered in 41% of patients. Postoperative CSF leak occurred in 22 cases (13.6%). The mean follow-up was 19 months, ranging from 0.2 to 63.6, and the mean performance status of patients with a follow-up of at least 12 months was 77 (range of 40-100). Recurrence or progression of disease was found in 13.7% of cases (follow-up 2 years or more). CONCLUSION: Our experience suggests that although posterior fossa meningiomas represent a continuing challenge for contemporary neurosurgeons, such tumors may be completely or subtotally removed with low rate of mortality and acceptable morbidity, allowing most of these patients to achieve a good outcome in a long-term follow-up.

Cerebral revascularization using radial artery grafts for the treatment of complex intracranial aneurysms: techniques and outcomes for 17 patients.

OBJECTIVE: The goal of this report is to illustrate the use of radial artery grafts as bypass conduits in the management of complex intracranial aneurysms and to describe a new "pressure distension technique" to eliminate postoperative vasospasm, which was a common problem early in our experience. METHODS: This study included a series of 17 patients who were surgically treated between 1994 and January 2001 for complex intracranial aneurysms. Five patients were surgically treated without the pressure distension technique; for 12 patients, the technique was used to reduce postoperative vasospasm. Fourteen of the patients had anterior circulation aneurysms, and three had posterior circulation aneurysms. Five of the patients had undergone previous attempts at direct clipping or excision and reconstruction of the aneurysm in question, and embolization had been performed for one patient with a carotid-cavernous fistula. Thirteen patients underwent permanent revascularization combined with proximal occlusion, trapping, or clipping, and four patients underwent temporary revascularization for cerebral protection during anticipated prolonged occlusion of the parent vessel during aneurysm dissection. Surgical techniques are described, with particular reference to vessel collection and bypass techniques. RESULTS: The outcomes for this group of patients, considering the complexity of the aneurysms and their "inoperability," with respect to direct clipping, were satisfactory. The aneurysms were completely obliterated for all patients, and the grafts were patent for all except one patient on postoperative angiograms. There were two deaths, one attributable to systemic sepsis and the other attributable to cardiac arrest during a transbronchial biopsy. The postoperative Glasgow Outcome Scale scores were either better or the same for all other patients, compared with their preoperative scores. Three of the five patients treated before the institution of the pressure distension technique experienced vasospasm of the graft, with two of those patients requiring angioplasty. For one of those patients, angioplasty led to rupture of the graft. Vasospasm was not observed for any of the 12 patients for whom the pressure distension technique was used. We observed no morbidity related to radial artery collection. CONCLUSION: Revascularization techniques are occasionally necessary for the surgical treatment of complicated intracranial aneurysms. The merits of the use of the radial artery as a bypass conduit are discussed. Radial artery grafts should be considered as alternatives to saphenous vein and superficial temporal artery grafts. The problem of vasospasm of the artery has been solved with the pressure distention technique.

Dural reconstruction with fascia, titanium mesh, and bone screws: technical note.

OBJECTIVE: After the resection of cranial base tumors, there may not be enough free dural margin left for reconstruction after involved bone and dura have been removed. In such a situation, dural reconstruction becomes a problem. We propose a new technique of dural closure in such cases. METHODS: A fascial graft is prepared from either fascia lata, abdominal fascia, pericranium, or temporal fascia and is trimmed to a size slightly larger than that of the dural defect. The fascial graft is placed over the dural defect and affixed to the underlying bone with a piece of titanium mesh, titanium screws, or both. The graft is then reinforced with fibrin glue. RESULTS: This method of dural reconstruction has been used in five patients with basal meningiomas. Three were in the petromastoid area, and two were in the planum-ethmoid area. None of these patients experienced postoperative cerebrospinal fluid leak, and none experienced any complications related to the reconstruction. CONCLUSION: This technique of dural reconstruction can be used in selected cases of basal tumors without enough free dural margin to sew into a fascial graft.

Cerebral revascularization in cranial base tumors.

Certain cranial base tumors may involve intracranial arteries by encasement or invasion. In such patients, resection of the tumor along with the involved artery is an option for treatment. Techniques and results of vascular bypasses for such lesions are discussed in this article.

Chordomas and chondrosarcomas of the skull base: results and complications of surgical management.

OBJECT: Chordomas and chondrosarcomas are rare and difficult to treat tumors for which the optimum treatment modality remains controversial. The aim of this study was to evaluate the surgery-related results and complications in a series of patients in whom radical resection was the treatment of choice. METHODS: The authors conducted a retrospective analysis of the surgery-related results and complications associated with chordoma and chondrosarcoma in 64 patients of whom 33 (52%) had previously undergone some form of treatment. Total or near-total excision was achieved in 56% and this rate increased to 68% in patients without prior treatment. The main complications were postoperative cerebrospinal fluid leakage, intraoperative arterial injury, and new-onset cranial nerve deficits. Arterial injury occurred only and perioperative death occurred more often in patients who had undergone previous treatment. CONCLUSIONS: Analysis of the results provides support for a policy of radical excision of chordomas and chondrosarcomas at the time of first presentation. A higher incidence of procedure-related complications is found in patients who have already undergone surgery and radiotherapy.