The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

Investment in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing in Africa over the past year has led to a major increase in the number of sequences that have been generated and used to track the pandemic on the continent, a number that now exceeds 100,000 genomes. Our results show an increase in the number of African countries that are able to sequence domestically and highlight that local sequencing enables faster turnaround times and more-regular routine surveillance. Despite limitations of low testing proportions, findings from this genomic surveillance study underscore the heterogeneous nature of the pandemic and illuminate the distinct dispersal dynamics of variants of concern-particularly Alpha, Beta, Delta, and Omicron-on the continent. Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve while the continent faces many emerging and reemerging infectious disease threats. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century.

A year of genomic surveillance reveals how the SARS-CoV-2 pandemic unfolded in Africa

The progression of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in Africa has so far been heterogeneous, and the full impact is not yet well understood. In this study, we describe the genomic epidemiology using a dataset of 8746 genomes from 33 African countries and two overseas territories. We show that the epidemics in most countries were initiated by importations predominantly from Europe, which diminished after the early introduction of international travel restrictions. As the pandemic progressed, ongoing transmission in many countries and increasing mobility led to the emergence and spread within the continent of many variants of concern and interest, such as B.1.351, B.1.525, A.23.1, and C.1.1. Although distorted by low sampling numbers and blind spots, the findings highlight that Africa must not be left behind in the global pandemic response, otherwise it could become a source for new variants.

Evaluation of a human in vitro skin test for predicting drug hypersensitivity reactions

The occurrence of drug hypersensitivity reactions (DHRs) following administration of low molecular weight (LMW) drugs is an important health concern. However, in vivo animal models which could be used as tools for the prediction of DHRs are lacking. As a result, research has focused on development of in vitro tools for predicting DHRs. In this study a novel human in vitro pre-clinical skin explant test was used to predict T cell-mediated hypersensitivity responses induced by LMW drugs. Responses in the skin explant test for 12 LMW drugs associated with T cell-mediated hypersensitivity in the clinic (abacavir, amoxicillin, carbamazepine, diclofenac, lamotrigine, lapatinib, lumiracoxib, nevirapine, ofloxacin, phenytoin, propranolol, sulfamethoxazole) were compared with responses for 5 drugs with few/no reports of T cell-mediated hypersensitivity reactions (acetaminophen, cimetidine, flecainide, metformin, verapamil). Changes in skin histology following in vitro exposure to the drugs as well as T cell proliferation and interferon gamma (IFNγ) production were studied. The results of the skin explant assays showed a good positive correlation (r = 0.77, p < .001) between the test outcome (prediction of positive or negative) and the clinical classification of the tested drugs. The T cell proliferation assay showed a correlation of r = 0.60 (p < .01) and the IFNγ assay r = 0.51 (p < .04). The data suggest that the skin explant model could be a useful tool to predict the potential of LMW drugs to induce DHRs.

Three-layer reconstruction of lower third nasal defects using forehead flap, reversed nasolabial flap, and auricular cartilage

The reconstruction of a full-thickness defect of the distal third of the nose requires the restoration of all three anatomical layers. A practical method for three-layer reconstruction of the lower third of the nose and the long-term results of this technique are presented herein. A combined reconstruction technique was utilized, including a reverse subcutaneous pedicled nasolabial flap to restore the nasal mucosa, an auricular cartilage graft for structural support, and a forehead flap for cutaneous coverage of the defect. This technique was applied in 21 patients following the full-thickness excision of basal cell carcinoma of the lower part of the nose. All patients (12 male and nine female; mean age 59.8 years) were treated successfully and were satisfied with the aesthetic and functional outcomes. The wound had to be further revised in three cases for the correction of contour or residual deformities; however, no further complications were experienced. One patient had a wound infection and the cartilage had to be removed. The grafting procedure was repeated successfully after resolution of the infection. Donor site morbidity was unremarkable. Combined flaps from the forehead and nasolabial regions with an incorporated auricular cartilage graft can be used to reconstruct full-thickness defects of the lower third of the nose.

Ease of insertion of the laryngeal mask airway in pediatric surgical patients: Predictors of failure and outcome

BACKGROUND

Laryngeal mask airway (LMA) is an useful alternative to endotracheal tube for airway management. The risk of life-threatening adverse respiratory events during its use is rare, but we need to know about the risk-adjusted prediction of its insertion failure requiring rescue tracheal intubation and its impact on patient outcome.

MATERIALS AND METHODS

Five hundred patients; 6 months to 12-year-old, American Society of Anesthesiologists I and II scheduled to undergo elective surgical procedures that require general anesthesia were included in this study. LMA was inserted after induction of anesthesia. The insertion conditions, intra, and postoperative events were recorded. Our primary outcome variable was trial success from the first time.

RESULTS

We recorded 426 cases (85.2%) of first trial success with clear airway compared to 46 case (9.2%) of second trial success (P ≤ 0.001). Predictors of failure of first attempt of LMA insertion include abnormal airway anatomy (91%), body weight <16 kg and age below 5 years (44%), the use of LMA size of 1 and 1.5 (3.8%), the intraoperative lateral position (3.8%).

CONCLUSION

The data obtained from this study support the use of the LMA as a reliable pediatric supraglottic airway device, demonstrating relatively low failure rates. Predictors of LMA failure in the pediatric surgical population should be independently considered.

TRIAL REGISTRATION

The study is registered in the Australian and New Zealand clinical trial registry with the allocated trial number: ACTRN12614000994684. Web address of trial: http://www.ANZCTR.org.au/A CTRN12614000994684.aspx.

Spread of carbapenem-resistant international clones of Acinetobacter baumannii in Turkey and Azerbaijan: a collaborative study

Epidemic clones of Acinetobacter baumannii, described as European clones I, II, and III, are associated with hospital epidemics throughout the world. We aimed to determine the molecular characteristics and genetic diversity between European clones I, II, and III from Turkey and Azerbaijan. In this study, a total of 112 bloodstream isolates of carbapenem-resistant Acinetobacter spp. were collected from 11 hospitals across Turkey and Azerbaijan. The identification of Acinetobacter spp. using conventional and sensitivity tests was performed by standard criteria. Multiplex polymerase chain reaction (PCR) was used to detect OXA carbapenemase-encoding genes (bla OXA-23-like, bla OXA-24-like, bla OXA-51-like, and bla OXA-58-like). Pulsed-field gel electrophoresis (PFGE) typing was used to investigate genetic diversity. The bla OXA-51-like gene was present in all 112 isolates, 75 (67 %) carried bla OXA-23-like, 7 (6.2 %) carried bla OXA-58-like genes, and 5 (4.5 %) carried bla OXA-24-like genes. With a 90 % similarity cut-off value, 15 clones and eight unique isolates were identified. The largest clone was cluster D, with six subtypes. Isolates from clusters D and I were widely spread in seven different geographical regions throughout Turkey. However, F cluster was found in the northern and eastern regions of Turkey. EU clone I was grouped within J cluster with three isolates found in Antalya, Istanbul, and Erzurum. EU clone II was grouped in the U cluster with 15 isolates and found in Kayseri and Diyarbakır. The bla OXA-24-like gene in carbapenemases was identified rarely in Turkey and has been reported for the first time from Azerbaijan. Furthermore, this is the first multicenter study in Turkey and Azerbaijan to identify several major clusters belonging to European clones I and II of A. baumannii.

An in vitro human skin test for assessing sensitization potential

Sensitization to chemicals resulting in an allergy is an important health issue. The current gold-standard method for identification and characterization of skin-sensitizing chemicals was the mouse local lymph node assay (LLNA). However, for a number of reasons there has been an increasing imperative to develop alternative approaches to hazard identification that do not require the use of animals. Here we describe a human in-vitro skin explant test for identification of sensitization hazards and the assessment of relative skin sensitizing potency. This method measures histological damage in human skin as a readout of the immune response induced by the test material. Using this approach we have measured responses to 44 chemicals including skin sensitizers, pre/pro-haptens, respiratory sensitizers, non-sensitizing chemicals (including skin-irritants) and previously misclassified compounds. Based on comparisons with the LLNA, the skin explant test gave 95% specificity, 95% sensitivity, 95% concordance with a correlation coefficient of 0.9. The same specificity and sensitivity were achieved for comparison of results with published human sensitization data with a correlation coefficient of 0.91. The test also successfully identified nickel sulphate as a human skin sensitizer, which was misclassified as negative in the LLNA. In addition, sensitizers and non-sensitizers identified as positive or negative by the skin explant test have induced high/low T cell proliferation and IFNγ production, respectively. Collectively, the data suggests the human in-vitro skin explant test could provide the basis for a novel approach for characterization of the sensitizing activity as a first step in the risk assessment process.

Response of first-line antibiotic therapy in patients with febrile neutropenia during treatment of hematological disorders

Patients with hematological disorders develop febrile neutropenia (FN); most of these events remain undetermined in origin. We performed a prospective study to determine the microbiological characteristics of infections and their response to the first-line antibiotic therapy in FN. The study was conducted at National Institute of Blood Disease and Bone Marrow Transplant. Two-hundred episodes of FN were assessed for the bacterial growth, antimicrobial susceptibility pattern and response to the first-line treatment of FN. All patients were given Ceftazidime and Amikacin Bosch Pharmaceutical (Pvt. Ltd), as first-line antibiotic in FN. Out of 200 episodes we had 108 clinically and microbiologically documented infections. The isolated frequencies for gram negative and gram positive organisms were n = 52 and 49 (48 and 45 %) respectively. Among gram negative micro-organisms, Escherichia coli (E. coli) was isolated in 15 (28.8 %), Klebsiella pneumonae in 4 (7.6 %) and Pseudomonas aeruginosa in 10 (19.2 %) were in highest frequencies. Methicillin sensitive staphylococci emerged as the frequently isolated gram-positive bacteria. Eight-one episodes (45.3 %) responded to the first-line treatment and death reported in 20 cases (10 %). Our study showed almost equal trend of gram positive and gram negative bacteria isolated from patients suffering from neutropenic fever. Empirical use of Ceftazidime and Amikacin as first-line antibiotics was able to cover the infection only in 45.3 % of episodes suffering from FN.

Study on serum glucose level among smear positive pulmonary tuberculosis patients in Bangladesh

This case control study was carried out in the Department of Biochemistry, Mymensingh Medical College, Bangladesh in cooperation with the Outpatient Department and Medicine Units of Mymensingh Medical College Hospital, Fulbaria Upazilla Health Complex, Mymensingh and some DOTS centers of BRAC, a non-government organization during the period of July 2006 to June 2007. The aim of the study was to explore the status of serum glucose level in smear positive Bangladeshi pulmonary tuberculosis patients. A total of 120 people of different age groups were included in this study. Subjects were divided into two groups - Group I (Control; n=60) - apparently healthy people selected matching by age, sex and socioeconomic status with the cases and Group II (Case; n=60) - people with smear positive pulmonary tuberculosis. Serum glucose (fasting) was estimated by colorimetric principle. Statistical analysis was done by using SPSS windows package. Among the groups, mean±SD of serum glucose (fasting) in Group II (5.91±1.02mmol/L) was significantly higher (p<0.001) than in Group I (4.87±0.57mmol/L). It is evident from the study that serum glucose level significantly increases in smear positive pulmonary tuberculosis patients.

Maintaining and restoring cytoplasmic male sterility systems in pepper (Capsicum annuum L.)

We studied the efficiency of maintaining and restoring cytoplasmic male sterility (CMS) systems in pepper (Capsicum annuum L.). An Rf-linked molecular marker was employed to analyze the interaction between 6 CMS lines (A), 5 maintainers (B), and 6 restorers (C). Sterility was maintained in the matings of lines 201A x 200B, 203A x 200B, 206A x 200B, 200A x 201B, 206A x 201B, 200A x 202B, 200A x 203B, 200A x 206B, and 201A x 206B. All 6 restorers restored the fertility of lines 200A, 202A, 203A, and 204A, except that 213C could not restore the fertility of lines 200A and 204A. However, the 6 restorers had diverse restoring abilities in individual CMS lines. The Rf-linked molecular marker was amplified by PCR in lines 207C, 208C, and 213C. This DNA marker was only found in the F1 hybrids M39, M14, M19, M25, M13, M20, and M22. We conclude that the restorers 208C and 207C can transmit the Rf gene or the Rf-linked marker to F1 hybrids.

Serum calcium level among smear positive pulmonary tuberculosis patients in Bangladesh

This case control study was carried out in the Department of Biochemistry, Mymensingh Medical College, Bangladesh in cooperation with the Outpatient Department and Medicine Units of Mymensingh Medical College Hospital, Fulbaria Upazilla Health Complex, Mymensingh and some DOTS centers of BRAC, a non-government organization during the period of July 2006 to June 2007. The aim of the study was to explore the status of serum calcium level in smear positive Bangladeshi pulmonary tuberculosis patients. A total of 120 people of different age groups were included in this study. Subjects were divided into two groups - Group I (Control; n=60) apparently healthy people selected matching by age, sex and socioeconomic status with the cases and Group II (Case; n=60) people with smear positive pulmonary tuberculosis. Serum calcium was estimated by colorimetric principle. Serum calcium was adjusted by serum albumin concentration. Statistical analysis was done by using SPSS windows package. Among the groups, mean±SD of adjusted serum calcium in Group II (2.41±0.15mmol/L) was significantly higher (p<0.001) than that in Group I (1.85±0.11mmol/L). It is evident from the study that serum calcium level significantly increases in smear positive Bangladeshi pulmonary tuberculosis patients.

The pollen wall and tapetum are altered in the cytoplasmic male sterile line RC₇ of Chinese cabbage (Brassica campestris ssp pekinensis)

Cytoplasmic male sterile line RC(7) of Chinese cabbage produces mature anthers without pollen. To understand the mechanisms involved, we examined the ultrastructural changes during development of the microspores. Development of microspores was not affected at the early tetrad stage. During the ring-vacuolated period, some large vacuoles appeared in the tapetum cells, making them larger, extending to the anther sac center during the monocyte period. At the same time, the tapetum degenerated as the microspores aborted, resulting in pollen-deficient anthers. As a result, the locules collapsed and the anthers shriveled. The callose was degraded in the pollen walls; abnormal deposits of electrodense material gave rise to irregular spike-shaped structures, rather than the characteristic rod-like shape of the B7 bacula. The internal intine wall of RC(7) was thinner than that of the B7 type. At the mitosis I microspore stage, the tapetum cells contained multiple plastids, with numerous small spherical plastoglobuli, and lipid bodies. Based on these observations, we suggest that RC(7) abortion may be due to mutated genes that normally regulate development of the pollen wall and cell walls in the RC(7) line.

Exogenous abscisic acid increases antioxidant enzymes and related gene expression in pepper (Capsicum annuum) leaves subjected to chilling stress

To elucidate how physiological and biochemical mechanisms of chilling stress are regulated by abscisic acid (ABA) pretreatment, pepper variety (cv. 'P70') seedlings were pretreated with 0.57 mM ABA for 72 h and then subjected to chilling stress at 10°/6°C (day/night). Chilling stress caused severe necrotic lesions on the leaves and increased malondialdehyde and H(2)O(2) levels. Activities of monodehydroascorbate reductase (DHAR), dehydroascorbate reductase, glutathione reductase, guaiacol peroxidase, ascorbate peroxidase, ascorbate, and glutathione increased due to chilling stress during the 72 h, while superoxide dismutase and catalase activities decreased during 24 h, suggesting that chilling stress activates the AsA-GSH cycle under catalase deactivation in pepper leaves. ABA pretreatment induced significant increases in the above-mentioned enzyme activities and progressive decreases in ascorbate and glutathione levels. On the other hand, ABA-pretreated seedlings under chilling stress increased superoxide dismutase and guaiacol peroxidase activities and lowered concentrations of other antioxidants compared with untreated chilling-stressed plants. These seedlings showed concomitant decreases in foliage damage symptoms, and levels of malondialdehyde and H(2)O(2). Induction of Mn-SOD and POD was observed in chilling-stressed plants treated with ABA. The expression of DHAR1 and DHAR2 was altered by chilling stress, but it was higher in the presence than in the absence of ABA at 24 h. Overall, the results indicate that exogenous application of ABA increases tolerance of plants to chilling-induced oxidative damage, mainly by enhancing superoxide dismutase and guaiacol peroxidase activities and related gene expression.

Pseudomyxoma peritonei - a case report

Pseudomyxoma peritonei (PMP) is rare in our clinical practice. The patient was a lady of 45 years admitted at the department of Obstetrics & Gynaecology in Sir Salimullah Medical College & Mitford Hospital (SSMC & MH) Dhaka with the complaints of swelling of the abdomen for 3 months associated with pain in the same region and weight loss. On examination a large swelling was palpated occupying the umbilical, hypogastric, both iliac, and part of both lumber regions. It was cystic, mildly tender, and immobile with ill defined margins. Computer tomography (CT) showed a cystic mass in the pelvic cavity extending upto the mid abdomen. Huge ascites was also noted. CT guided FNAC showed benign mucinous cystadenoma. Laparotomy was done which showed that the peritoneal cavity was filled up with mucinous material and there was a tumor in the right ovary which was free from adhesion. Left ovary and uterus were atrophic. Hysterectomy with bilateral salpingoophorectomy was done. Abdomen was cleared from the mucinous material as far as possible. Her postoperative recovery was uneventful. Histopathology report showed borderline mucinous cystadenoma of the ovary. She was referred to the oncology department. No chemotherapy was given but kept under follow-up.

Bilateral Transverse Facial Cleft as an Isolated and Asyndromic Deformity

Congenital macrostomia or transverse facial cleft is a rare congenital craniofacial anomaly, which affects the esthetics and functions of oral cavity. It is usually associated with deformities of other structures developed from the first and second branchial arches. Bilateral transverse cleft, occurring alone is uncommon. Since the deformity is rare, its treatment has not been commonly described in the literature. We report a case of congenital bilateral macrostomia as an isolated, asyndromic deformity to add one more case in the literature and surgical technique has been discussed here.

Fixed drug eruptions due to cotrimoxazole

This prospective study on Fixed Drug Eruption (FDE) was carried out between January 2003 to December 2006 in Dermatology department of Mymensingh Medical College Hospital & private chambers. This study was carried out with an objective to see the specific site of involvement and other clinical parameters in FDE due to cotrimoxazole. In each case, a detailed history was taken and a thorough physical examination was done by at least one dermatologist. Patients with suspected FDE, who had consented, were included in the study. Oral re-challenge test was done in each case after written or verbal consent of the patient or legal guardian. For oral re-challenge, usually half of the usual therapeutic dose of the suspected drug (s) was given first and reactions were observed and if no reaction, then full therapeutic dose was given and then again reactions were observed. In case of no reaction to one drug, the next drug was tested after 2 to 7 days. Age & sex distribution, number of attacks of FDE, number of lesions, distribution of sites of involvement were determined in each case of FDE. All informations were recorded in pre-tested data sheet. Among 93 patients of suspected FDE, 61 patients were confirmed as FDE with identified causes, of which 36 cases were due to cotrimoxazole (59.02%). Age range of patients was from 5 years to 65 years with mean of 24.92 years. Male was predominantly affected (M:F=6.2:1). In 50% cases presenting attack was the 2nd attack. Rest 50% had 3 to more than 10 attacks. Number of lesions was: 2-5 lesions in 50%, solitary lesion in 16.67%, 6-10 lesions in 13.89% and more than 10 lesions in 19.44% cases. Sites of involvement in cases of FDE due to cotrimoxazole (n=36) were as follows: lips 58.33%, genitalia 33.33%, oral 13.89%, trunk 38.89%, limbs 55.56%, hands 16.67%, feet 19.44%, face 19.44% and conjunctiva 2.78%.

Delayed replantation of avulsed teeth

Dental injuries are very common and their extent has been classified by Ellis. Avulsion of tooth is a grievous injury and ranges from 1-16% among the traumatic injuries, of which maxillary anterior are commonest. Reimplantation of avulsed teeth is a standard procedure. However, it has certain limitations. Most often their management is very challenging. In this case report we are presenting the management of maxillary incisors by replantation after 36 hrs in a 12 year old girl.

Unusual manifestation of a concurrent demodectic and sarcoptic mange in a Zebu-Friesian cross-bred heifer

We describe a rare case of a concurrent demodectic and sarcoptic mange in a 2-year-old heifer in Khartoum, Sudan. The lesions were massive lumps of granulomatous tumour-like dermatitis with thick, nodular folds mainly covering the head, neck and shoulders. Histopathological examination of the lesions revealed the presence of both Demodex bovis and Sarcoptes scabiei. The animal died regardless of the anti-parasitic treatment it received.

Behavioral effects of acute and chronic triazolam treatments in albino rats

Previous behavioral studies on triazolam (TZ), which are small in number, could only speculate about tolerance to the anxiolytic effect of TZ, as the experiments did not cover sufficient time (of 4 to 7 days) for tolerance to develop. Therefore longer time for chronic TZ administration is used. We investigated the effects of TZ on motor activity and exploratory behavior using plus maze and open field. Three experiments were conducted. In the first, five groups of rats were acutely treated with different doses of TZ (0.25 mg/kg-4.0 mg/kg). In the second set of experiments, rats were treated chronically with a single daily dose of TZ (started with 0.25 mg/kg and increased by time to 1.0 mg/kg) for 5 weeks (representing clinical use). In the third, rats were treated chronically with three daily doses of TZ (started with 0.25 mg/kg and increased by time to 0.5 mg/kg) for 20 days (mimicking drug abuse). Acute TZ administration produced dose dependent anxiolytic effects and a decrease in motor activity with higher doses. Chronically treated rats, either once daily or three times daily doses, showed tolerance to both anxiolytic and sedative effects of TZ. It may be concluded that tolerance to the anxiolytic and sedative effects of TZ would develop after chronic administration either with clinical use or its abuse.